Required Resources
Text
· Botkin, D. B., & Keller, E. A. (2014). Environmental science: Earth as a living planet (9th ed.). Hoboken, NJ: John Wiley & Sons, Inc
· Chapter 4: The Big Picture: Systems of Change
· Chapter 6: Ecosystems: Concepts and Fundamentals
Multimedia
· Annenberg Learner. (n.d.). Unit 4: Ecosystems [Interactive resource]. In The Habitable Planet. Retrieved from http://www.learner.org/courses/envsci/unit/text.php?unit=4&secNum=0
Classics Theorists Notes
Classics Discussion
When talking the role of manager we are talking about Taylor, Faole and Gulick.
· Wilsons Dichotomy (1887)
(NEED TO KNOW)
· Politics and Administration are SEPERATE
· Politics
· Purpose: Create Policy
· Involved: elected officials responsible for the creation of policy
· Laws
· Ordinances
· Policy
· Administration (The Machine)
· Purpose: To implement policy
· Involved: Everyone who is employed by the government agency including…
· Military
· First responders
· Social services
· Parks and rec, ect
· Even if we (administrators) do not agree with the law, we still have to enforce it
Fredrick Taylor (talks about role of the manager)
-If nothing else, he was about EFFICIENCY
-All about standardizing the methods of business
-Consistency
-Management is the expert of the process
-The beginning of the white-collar workforce
-Created a science behind industrial work or any type of work realistically
-Concerned more with the efficiency than care and respect
-Wanted to (and did) create replaceable labor
-Wanted to create an industrial utopia (great in theory, nearly impossible in practice)
-His incentive was not to cut the piece rate for his workers but to pay them more for their improved efficiency.
-This was not the norm of business operation
-Taylors Scientific Management method made up for the lack of human efficiency
-He found a way to improve what was thought to be nonimprovable
-Only worthy managers should be managers (Managers are not to be lazy, or entitled, or dominant of thought over their workers)
-The idea was that this scientific management could be applied to all forms of life (school, government work, lifestyle, ect.)
Max Weber 1922 (Father of Bureaucracy) talks about: organizational structure
-Six characteristics of Bureaucracy (more about how we manage not how we govern)
1. Well defined formal hierarchy of command
2. Management by rules and regulations
3. Division of labor and work specialization
4. Managers should maintain an impersonal relationship with their employees
5. Competence and not personality should be basis for job appointment
6. Formal rules, regulation, procedures, decisions, and actions by the organization and its members should be recorded in order to preserve consistency and accountability.
Marry Parker Follett 1926 (Talks about leadership and management style)
-Recognized the holistic nature of community and advanced the idea of reciprocal relationships in understanding the dynamic aspects of the individual in the relat ...
The document discusses managing people and organizations. It covers several topics:
- Three essential skills for managers according to Katz: technical, human, and conceptual skills.
- Fayol's five original management functions that later condensed into four categories: planning, organizing, directing, and controlling.
- Cognitive dissonance theory which holds that individuals seek to reduce inconsistency between attitudes and behaviors.
- Implications of cognitive dissonance theory for organizational life including changing attitudes, behaviors, or information to reduce dissonance.
This document provides an overview of organizational behavior as a field of study. It defines OB as investigating how individuals, groups, and structure impact behavior in organizations. The field draws from disciplines like psychology, sociology, and anthropology. The document traces the historical evolution of OB, including early contributions from Adam Smith, Frederick Taylor, and Elton Mayo. It discusses how OB aims to improve productivity, reduce absenteeism, and increase job satisfaction. Maslow's hierarchy of needs and McGregor's Theory X and Y are also summarized as influencing the development of OB.
Evolution of management theory,Scientific Management School
Classical Organization Theory school
Behavioral School
Management Science School
The System Approach
The Contingency Approach
Dynamic Engagement Approach
This document provides an overview of the evolution of management theories from the early 1900s to recent times. It discusses four main approaches: scientific management, general administrative theories, organizational behavior/human relations, and quantitative approaches. It also summarizes the contributions of important theorists like Taylor, Fayol, Weber, Barnard, and Maslow. Recent decades have seen a movement toward integrating different theories and addressing new issues like diversity, ethics, innovation, and contingent workforces.
grade 11 organization and management: lesson 1LezelCRamos
Management refers to coordinating work activities to achieve organizational goals. It involves teamwork and people working harmoniously. Management is essential in any organization and is goal-oriented, universal, continuous, multi-disciplinary, and both a science and an art. Early management theories focused on physical resources and job tasks, while later theories emphasized psychology and group relationships. The systems approach views the organization as an adaptive system that must adjust to its environment through interconnected subsystems like input, process, output, feedback, and the external environment.
The document discusses several theories and models of leadership including:
1. Three styles of leadership - authoritarian, democratic, and laissez-faire. It describes the characteristics of each style.
2. Two orientations of leadership - task orientation which focuses on accomplishing goals, and interpersonal orientation which focuses on relationships.
3. The historical evolution of leadership theories including the trait, behavioral, situational, and transformational approaches. It provides examples of theories within each approach.
The document also discusses management theories including:
1. McGregor's Theory X and Theory Y, which identify two approaches that managers take towards supervision and employee motivation.
2. Definitions of management and the goals of
Management involves coordinating work through other people to achieve organizational goals efficiently and effectively. There are three levels of management: top management sets strategy, middle management implements strategy, and first-line management oversees entry-level employees. Early management theorists like Taylor, Fayol, and Weber developed classical approaches to management focusing on specialization, authority, and bureaucracy. Behavioral theorists like Hawthorne highlighted the importance of human factors, while McGregor's Theory X and Y distinguished coercive vs. empowering management styles. Contemporary approaches include Ouchi's Theory Z emphasizing culture and contingency theory adapting to changing situations.
The document discusses managing people and organizations. It covers several topics:
- Three essential skills for managers according to Katz: technical, human, and conceptual skills.
- Fayol's five original management functions that later condensed into four categories: planning, organizing, directing, and controlling.
- Cognitive dissonance theory which holds that individuals seek to reduce inconsistency between attitudes and behaviors.
- Implications of cognitive dissonance theory for organizational life including changing attitudes, behaviors, or information to reduce dissonance.
This document provides an overview of organizational behavior as a field of study. It defines OB as investigating how individuals, groups, and structure impact behavior in organizations. The field draws from disciplines like psychology, sociology, and anthropology. The document traces the historical evolution of OB, including early contributions from Adam Smith, Frederick Taylor, and Elton Mayo. It discusses how OB aims to improve productivity, reduce absenteeism, and increase job satisfaction. Maslow's hierarchy of needs and McGregor's Theory X and Y are also summarized as influencing the development of OB.
Evolution of management theory,Scientific Management School
Classical Organization Theory school
Behavioral School
Management Science School
The System Approach
The Contingency Approach
Dynamic Engagement Approach
This document provides an overview of the evolution of management theories from the early 1900s to recent times. It discusses four main approaches: scientific management, general administrative theories, organizational behavior/human relations, and quantitative approaches. It also summarizes the contributions of important theorists like Taylor, Fayol, Weber, Barnard, and Maslow. Recent decades have seen a movement toward integrating different theories and addressing new issues like diversity, ethics, innovation, and contingent workforces.
grade 11 organization and management: lesson 1LezelCRamos
Management refers to coordinating work activities to achieve organizational goals. It involves teamwork and people working harmoniously. Management is essential in any organization and is goal-oriented, universal, continuous, multi-disciplinary, and both a science and an art. Early management theories focused on physical resources and job tasks, while later theories emphasized psychology and group relationships. The systems approach views the organization as an adaptive system that must adjust to its environment through interconnected subsystems like input, process, output, feedback, and the external environment.
The document discusses several theories and models of leadership including:
1. Three styles of leadership - authoritarian, democratic, and laissez-faire. It describes the characteristics of each style.
2. Two orientations of leadership - task orientation which focuses on accomplishing goals, and interpersonal orientation which focuses on relationships.
3. The historical evolution of leadership theories including the trait, behavioral, situational, and transformational approaches. It provides examples of theories within each approach.
The document also discusses management theories including:
1. McGregor's Theory X and Theory Y, which identify two approaches that managers take towards supervision and employee motivation.
2. Definitions of management and the goals of
Management involves coordinating work through other people to achieve organizational goals efficiently and effectively. There are three levels of management: top management sets strategy, middle management implements strategy, and first-line management oversees entry-level employees. Early management theorists like Taylor, Fayol, and Weber developed classical approaches to management focusing on specialization, authority, and bureaucracy. Behavioral theorists like Hawthorne highlighted the importance of human factors, while McGregor's Theory X and Y distinguished coercive vs. empowering management styles. Contemporary approaches include Ouchi's Theory Z emphasizing culture and contingency theory adapting to changing situations.
This document provides an overview of various models and theories of management thought from 1890 to present. It discusses early classical approaches from Taylor's scientific management to Fayol's administrative management. Contemporary approaches discussed include human relations theory, contingency theory and organizational behavior. Various management thinkers are summarized, including Follett, Mayo, Maslow, McGregor, Barnard, Mintzberg and Ouchi. The document also discusses models of nursing administration, including contextual factors, fields of inquiry, and the Canadian Association model and standards.
Theoretical Perspectives of Public AdministrationPadmini Naik
This document outlines several classical theories of public administration, including Scientific Management by Taylor, Administrative Management by Fayol, Gulick, and Urwick, and Max Weber's Bureaucracy theory. It describes key aspects of each theory such as their view of the prevailing state of management/administration at the time, main principles and techniques proposed, and their focus on improving efficiency. Administrative Management theorists in particular emphasized functions of management, principles of organization, and departmentalization. The document provides details on the background and major contributions of theorists like Taylor, Fayol, Gulick, and Urwick to establish foundational concepts in public administration.
Managerial roles involve interpersonal, informational, and decisional responsibilities. Interpersonal roles like leader and liaison involve relationships with subordinates and external parties. Informational roles like monitor and disseminator involve collecting and sharing information. Decisional roles like disturbance handler and resource allocator involve making choices. Managers need skills in areas like planning, human relations, conceptual thinking, interpersonal interaction, technical expertise, and politics. Organizations operate within an internal environment of structure and culture and an external environment influenced by economic, demographic, technological, sociocultural, political/legal, and global forces that impact managerial decisions.
This document provides notes on management theories and approaches. It discusses classical approaches like scientific management and bureaucracy. It also covers administrative approaches, human resources approaches, quantitative approaches, systems perspectives, and contingency approaches. Specific contributors and their works are outlined, such as Taylor's principles of scientific management, Fayol's functions of management, and Maslow's hierarchy of needs. Attributes of excellence from Peters and Waterman are also summarized.
The Evolution Of Management Theory.pptxSHAWNTAKAONA
Management theories have evolved over time from classical approaches focusing on structure and authority to more modern approaches considering people and external environments. Early theories included scientific management, bureaucratic management, and human relations approaches. Contemporary theories view organizations as open systems influenced by internal and external factors, with no single optimal approach but instead contingency-based solutions dependent on each organization's unique situation. The evolution of management theory continues as the business environment changes.
This document discusses administration and management. It defines administration as the direction, coordination and control of many people to achieve some purposes or objectives. It also discusses the meaning, definition and concepts of management. It describes the functions/elements of administration according to Luther Gulick as POSDCORB (Planning, Organizing, Staffing, Directing, Coordinating, Reporting and Budgeting). It also discusses the principles of administration according to Henri Fayol and theories of management such as classical, neo-classical and modern organizational theories.
This material is for PGPSE / CSE students of AFTERSCHOOOL. PGPSE / CSE are free online programme - open for all - free for all - to promote entrepreneurship and social entrepreneurship PGPSE is for those who want to transform the world. It is different from MBA, BBA, CFA, CA,CS,ICWA and other traditional programmes. It is based on self certification and based on self learning and guidance by mentors. It is for those who want to be entrepreneurs and social changers. Let us work together. Our basic idea is that KNOWLEDGE IS FREE & AND SHARE IT WITH THE WORLD
This document provides an overview of management principles and theories. It discusses classical and neo-classical approaches, including contributions from Taylor, Fayol, Weber, and Mayo. Contemporary theories like systems approach and contingency approach are also summarized. Various management functions such as planning, organizing, staffing and controlling are explained.
This document provides an overview of management principles and practices. It discusses key concepts from classical management thinkers like Taylor, Fayol, and Weber. It also summarizes more modern approaches like human relations theory, contingency theory, and systems theory. The document aims to give introductory ideas about basic management topics and encourage readers to use their knowledge to create social change as social entrepreneurs.
This document discusses several theories of management that may be useful for nursing leaders to consider, including: classical management theory, scientific management theory, human relations theory, and behavioral management theories. It provides an overview of several influential thinkers in management theory such as Taylor, Fayol, Maslow, and Likert. The document emphasizes that no single theory can guide nursing leadership in every situation, and leaders should consider multiple theories to develop an effective individual management style.
This document contains surveys from three individuals on how a new city ordinance affected their lives and livelihoods. Randy Cruz, a rice and sari-sari store owner, says it was difficult at first but he has gotten used to it, and his daily income is still enough. Robert Berdan, a newspaper and food seller, says he and his father did nothing wrong and the ordinance was removed them immediately without notice. Cherry Carino, a fish and meat vendor, says vendors should not be immediately dismissed and requests consideration or an extension before being evicted.
This document provides an overview of key management concepts and theories including: Taylor's scientific management theory, Fayol's principles of management, Mayo's Hawthorne experiments, Maslow's hierarchy of needs, McGregor's Theory X and Theory Y, Herzberg's two-factor theory, systems approach to management, leadership styles, and the social responsibilities of management. It defines management, discusses its nature and importance, and outlines common management functions proposed by various theorists.
Mini-Paper #2
Classical Organization Theory
Organization and Theory
My essay is based on chapter one of Classics of Organization Theory; which is focusing on the classical organization theory. I will discuss issues dealing with the history of the classical organization theory and some of the theorists that contributed to the theory; such as Henri Fayol, Frederick Winslow Taylor, and Luther Gulick.
The history of classical organization theory can be traced back to Muslims, Hebrews, Greeks, and Romans, and other origins dating back to the medieval times and biblical times. One example of usage of the classical organization theory is in the Book of Exodus, Chapter Eighteen. Moses’ father-in-law, Jethro chastised Moses for failing to create an organization where he can delegate responsibilities for the administration. Later, in the eighteenth century, in Great Britain, the factory system was implemented. The factory system caused problems where managers had to arrange for organizing reliable large-scale production. Great Britain is also the birthplace of the economic organization.
Henri Fayol was a former French mining engineer, who developed the basic theory of business administration. He was also one of the most influential contributors to modern management concepts. His main theory that is explained in the book discusses the principles of management; which includes the division of work, authority and responsibility, discipline, unity of command, unity of direction, subordination of individual and general interest, remuneration of personnel, centralization, scalar chain, order, equity, stability of tenure of personnel, initiative, and esprit de corps.
1. The division of work’s main objective is to create better work with the same amount of effort. It permits the reduction in the number of objects that attention has to be focused on.
2. The second principle of management is authority and responsibility. Authority is considered to be the right to give orders and have power of obedience. Responsibility is considered as a consequence and counterpart. The degree of responsibility has to be established.
3. Discipline is the third principle of management. It is considered the obedience, application, and energy of respect that is observed in accordance with the standing agreements between employees and firms.
4. The fourth principle of management is unity of command, which arises from general and ever-present necessities. The dual command is very common and wreaks havoc in large and small situations.
5. Unity of direction is the fifth principle of management, which is expressed through one head and one plan for a group of activities that have the same objective. It is very important to the unity of command, but should not be confused with the fourth principle. Unity of direction is provided for the body of a corporation.
6. The sixth principle of management is subordination of individual interests to general interests, which means ...
Here are some key points to consider when planning:
Characteristics of Good Planning:
- Be Specific and Realistic
- Consider Alternatives and Contingencies
- Coordinate Plans with other Functions and Departments
- Review and Revise Plans Periodically
The document summarizes several foundational theories in organizational communication from the Scientific Management and Human Behavior schools. The Scientific Management perspective, developed by Frederick Taylor and Henri Fayol, emphasized rational organizational design, worker training, and top-down communication. In contrast, the Human Behavior school, represented by theorists like Mary Parker Follett, Elton Mayo, and Rensis Likert, shifted the focus to interactions, motivation, and participation. While Scientific Management principles still influence organizations today, the Human Behavior theories highlighted the social aspects of work and importance of communication at all levels.
The document discusses different perspectives on management from various theorists. It provides definitions of management from Mary Parker Follett, George R. Terry, and F.W. Taylor. It also outlines the evolution of management theories including scientific management, administrative management, behavioral management, management science, and organizational environment theories. Key aspects of each theory are summarized such as Frederick Taylor's four principles of scientific management and Henri Fayol's fourteen principles of administrative management. The document also discusses different management styles including autocratic, consultative, persuasive, democratic, and laissez-faire.
This document summarizes key concepts from classical organizational theory and the human relations approach. It discusses Taylor's scientific management theory and Gulick's POSDCORB functions of management. It also covers the Hawthorne studies conducted by Elton Mayo, which demonstrated the importance of socio-psychological factors in productivity. Finally, it discusses Abraham Maslow's hierarchy of needs and how the behavioral science approach contributed to understanding human behavior in organizations.
Management involves coordinating work through other people to be efficient and effective. Theories of management have evolved from classical approaches focusing on scientific principles to more modern behavioral approaches. Contemporary approaches emphasize contingency based on organizational circumstances. Management involves planning, organizing, staffing, leading, and controlling at different levels from top management setting strategy to first-line supervision of entry-level employees.
This document provides an introduction and overview of leadership and management. It begins by defining key terms like manager and leader. It then discusses the differences between managers and leaders as well as between management and leadership. The document also covers the historical development of management theories from bureaucracy to scientific management to human relations approaches. Finally, it discusses several approaches to leadership, including traditional, contingency, situational, and path-goal theories of leadership.
A brief description of your employment historyYour career .docxsodhi3
A brief description of your employment history
Your career goals (both short and long term)
Tell me about a leader you look up to. This can be someone you know or don't know, famous or familiar to you, and can even be a TV/Movie character and does not need to real. Describe what this person does makes them your role model.
(My name is Danny Z. i'm a full time student )
.
A budget is a plan expressed in dollar amounts that acts as a ro.docxsodhi3
A budget is a plan expressed in dollar amounts that acts as a road map to carry out an organization’s objectives, strategies and assumptions. There are different types of budgets that healthcare organization use to manage its financial and managerial goals and obligations.
Discuss the difference between an operating budget and a capital budget. What are the steps in creating each budget?
At least 150 words; APA Format
.
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This document provides an overview of various models and theories of management thought from 1890 to present. It discusses early classical approaches from Taylor's scientific management to Fayol's administrative management. Contemporary approaches discussed include human relations theory, contingency theory and organizational behavior. Various management thinkers are summarized, including Follett, Mayo, Maslow, McGregor, Barnard, Mintzberg and Ouchi. The document also discusses models of nursing administration, including contextual factors, fields of inquiry, and the Canadian Association model and standards.
Theoretical Perspectives of Public AdministrationPadmini Naik
This document outlines several classical theories of public administration, including Scientific Management by Taylor, Administrative Management by Fayol, Gulick, and Urwick, and Max Weber's Bureaucracy theory. It describes key aspects of each theory such as their view of the prevailing state of management/administration at the time, main principles and techniques proposed, and their focus on improving efficiency. Administrative Management theorists in particular emphasized functions of management, principles of organization, and departmentalization. The document provides details on the background and major contributions of theorists like Taylor, Fayol, Gulick, and Urwick to establish foundational concepts in public administration.
Managerial roles involve interpersonal, informational, and decisional responsibilities. Interpersonal roles like leader and liaison involve relationships with subordinates and external parties. Informational roles like monitor and disseminator involve collecting and sharing information. Decisional roles like disturbance handler and resource allocator involve making choices. Managers need skills in areas like planning, human relations, conceptual thinking, interpersonal interaction, technical expertise, and politics. Organizations operate within an internal environment of structure and culture and an external environment influenced by economic, demographic, technological, sociocultural, political/legal, and global forces that impact managerial decisions.
This document provides notes on management theories and approaches. It discusses classical approaches like scientific management and bureaucracy. It also covers administrative approaches, human resources approaches, quantitative approaches, systems perspectives, and contingency approaches. Specific contributors and their works are outlined, such as Taylor's principles of scientific management, Fayol's functions of management, and Maslow's hierarchy of needs. Attributes of excellence from Peters and Waterman are also summarized.
The Evolution Of Management Theory.pptxSHAWNTAKAONA
Management theories have evolved over time from classical approaches focusing on structure and authority to more modern approaches considering people and external environments. Early theories included scientific management, bureaucratic management, and human relations approaches. Contemporary theories view organizations as open systems influenced by internal and external factors, with no single optimal approach but instead contingency-based solutions dependent on each organization's unique situation. The evolution of management theory continues as the business environment changes.
This document discusses administration and management. It defines administration as the direction, coordination and control of many people to achieve some purposes or objectives. It also discusses the meaning, definition and concepts of management. It describes the functions/elements of administration according to Luther Gulick as POSDCORB (Planning, Organizing, Staffing, Directing, Coordinating, Reporting and Budgeting). It also discusses the principles of administration according to Henri Fayol and theories of management such as classical, neo-classical and modern organizational theories.
This material is for PGPSE / CSE students of AFTERSCHOOOL. PGPSE / CSE are free online programme - open for all - free for all - to promote entrepreneurship and social entrepreneurship PGPSE is for those who want to transform the world. It is different from MBA, BBA, CFA, CA,CS,ICWA and other traditional programmes. It is based on self certification and based on self learning and guidance by mentors. It is for those who want to be entrepreneurs and social changers. Let us work together. Our basic idea is that KNOWLEDGE IS FREE & AND SHARE IT WITH THE WORLD
This document provides an overview of management principles and theories. It discusses classical and neo-classical approaches, including contributions from Taylor, Fayol, Weber, and Mayo. Contemporary theories like systems approach and contingency approach are also summarized. Various management functions such as planning, organizing, staffing and controlling are explained.
This document provides an overview of management principles and practices. It discusses key concepts from classical management thinkers like Taylor, Fayol, and Weber. It also summarizes more modern approaches like human relations theory, contingency theory, and systems theory. The document aims to give introductory ideas about basic management topics and encourage readers to use their knowledge to create social change as social entrepreneurs.
This document discusses several theories of management that may be useful for nursing leaders to consider, including: classical management theory, scientific management theory, human relations theory, and behavioral management theories. It provides an overview of several influential thinkers in management theory such as Taylor, Fayol, Maslow, and Likert. The document emphasizes that no single theory can guide nursing leadership in every situation, and leaders should consider multiple theories to develop an effective individual management style.
This document contains surveys from three individuals on how a new city ordinance affected their lives and livelihoods. Randy Cruz, a rice and sari-sari store owner, says it was difficult at first but he has gotten used to it, and his daily income is still enough. Robert Berdan, a newspaper and food seller, says he and his father did nothing wrong and the ordinance was removed them immediately without notice. Cherry Carino, a fish and meat vendor, says vendors should not be immediately dismissed and requests consideration or an extension before being evicted.
This document provides an overview of key management concepts and theories including: Taylor's scientific management theory, Fayol's principles of management, Mayo's Hawthorne experiments, Maslow's hierarchy of needs, McGregor's Theory X and Theory Y, Herzberg's two-factor theory, systems approach to management, leadership styles, and the social responsibilities of management. It defines management, discusses its nature and importance, and outlines common management functions proposed by various theorists.
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My essay is based on chapter one of Classics of Organization Theory; which is focusing on the classical organization theory. I will discuss issues dealing with the history of the classical organization theory and some of the theorists that contributed to the theory; such as Henri Fayol, Frederick Winslow Taylor, and Luther Gulick.
The history of classical organization theory can be traced back to Muslims, Hebrews, Greeks, and Romans, and other origins dating back to the medieval times and biblical times. One example of usage of the classical organization theory is in the Book of Exodus, Chapter Eighteen. Moses’ father-in-law, Jethro chastised Moses for failing to create an organization where he can delegate responsibilities for the administration. Later, in the eighteenth century, in Great Britain, the factory system was implemented. The factory system caused problems where managers had to arrange for organizing reliable large-scale production. Great Britain is also the birthplace of the economic organization.
Henri Fayol was a former French mining engineer, who developed the basic theory of business administration. He was also one of the most influential contributors to modern management concepts. His main theory that is explained in the book discusses the principles of management; which includes the division of work, authority and responsibility, discipline, unity of command, unity of direction, subordination of individual and general interest, remuneration of personnel, centralization, scalar chain, order, equity, stability of tenure of personnel, initiative, and esprit de corps.
1. The division of work’s main objective is to create better work with the same amount of effort. It permits the reduction in the number of objects that attention has to be focused on.
2. The second principle of management is authority and responsibility. Authority is considered to be the right to give orders and have power of obedience. Responsibility is considered as a consequence and counterpart. The degree of responsibility has to be established.
3. Discipline is the third principle of management. It is considered the obedience, application, and energy of respect that is observed in accordance with the standing agreements between employees and firms.
4. The fourth principle of management is unity of command, which arises from general and ever-present necessities. The dual command is very common and wreaks havoc in large and small situations.
5. Unity of direction is the fifth principle of management, which is expressed through one head and one plan for a group of activities that have the same objective. It is very important to the unity of command, but should not be confused with the fourth principle. Unity of direction is provided for the body of a corporation.
6. The sixth principle of management is subordination of individual interests to general interests, which means ...
Here are some key points to consider when planning:
Characteristics of Good Planning:
- Be Specific and Realistic
- Consider Alternatives and Contingencies
- Coordinate Plans with other Functions and Departments
- Review and Revise Plans Periodically
The document summarizes several foundational theories in organizational communication from the Scientific Management and Human Behavior schools. The Scientific Management perspective, developed by Frederick Taylor and Henri Fayol, emphasized rational organizational design, worker training, and top-down communication. In contrast, the Human Behavior school, represented by theorists like Mary Parker Follett, Elton Mayo, and Rensis Likert, shifted the focus to interactions, motivation, and participation. While Scientific Management principles still influence organizations today, the Human Behavior theories highlighted the social aspects of work and importance of communication at all levels.
The document discusses different perspectives on management from various theorists. It provides definitions of management from Mary Parker Follett, George R. Terry, and F.W. Taylor. It also outlines the evolution of management theories including scientific management, administrative management, behavioral management, management science, and organizational environment theories. Key aspects of each theory are summarized such as Frederick Taylor's four principles of scientific management and Henri Fayol's fourteen principles of administrative management. The document also discusses different management styles including autocratic, consultative, persuasive, democratic, and laissez-faire.
This document summarizes key concepts from classical organizational theory and the human relations approach. It discusses Taylor's scientific management theory and Gulick's POSDCORB functions of management. It also covers the Hawthorne studies conducted by Elton Mayo, which demonstrated the importance of socio-psychological factors in productivity. Finally, it discusses Abraham Maslow's hierarchy of needs and how the behavioral science approach contributed to understanding human behavior in organizations.
Management involves coordinating work through other people to be efficient and effective. Theories of management have evolved from classical approaches focusing on scientific principles to more modern behavioral approaches. Contemporary approaches emphasize contingency based on organizational circumstances. Management involves planning, organizing, staffing, leading, and controlling at different levels from top management setting strategy to first-line supervision of entry-level employees.
This document provides an introduction and overview of leadership and management. It begins by defining key terms like manager and leader. It then discusses the differences between managers and leaders as well as between management and leadership. The document also covers the historical development of management theories from bureaucracy to scientific management to human relations approaches. Finally, it discusses several approaches to leadership, including traditional, contingency, situational, and path-goal theories of leadership.
Similar to Required ResourcesText· Botkin, D. B., & Keller, E. A. (.docx (20)
A brief description of your employment historyYour career .docxsodhi3
A brief description of your employment history
Your career goals (both short and long term)
Tell me about a leader you look up to. This can be someone you know or don't know, famous or familiar to you, and can even be a TV/Movie character and does not need to real. Describe what this person does makes them your role model.
(My name is Danny Z. i'm a full time student )
.
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A budget is a plan expressed in dollar amounts that acts as a road map to carry out an organization’s objectives, strategies and assumptions. There are different types of budgets that healthcare organization use to manage its financial and managerial goals and obligations.
Discuss the difference between an operating budget and a capital budget. What are the steps in creating each budget?
At least 150 words; APA Format
.
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A 72-year-old male with a past medical history for hypertension, congestive heart failure, chronic back pain, and diabetes is admitted to the hospital for hypotension suspected from a possible accidental overdose. What are the criteria for discharge? Explain the importance of utilizating hospital recommendations and teachings. List some meaningful community resources in the response.
.
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Code of Ethics: This is a synopsis of some of the most important ethical
considerations you need to be aware of as a professional in the real estate
industry.
Terminology:
Agency: The fiduciary relationship created between a principal and an agent whereby the agent
can act on behalf of the principle for certain transactions. Agency is usually created when the
principal signs a listing agreement to list their property for sale or a management contract to rent
a property for instance.
Agent: The broker or sales associate acting on behalf of the principal (see Agency)
Client: The person with whom the broker or sales associate has a legal contract to represent.
Customer: Is not contractually bound to the industry professional
Principal: Person who hires an agent to act on his or behalf.
Code of Ethics:
#1: The agent has a responsibility to promote the interests of their client(s) and treat all involved
in any real estate transaction in an honest and fair manner. They must disclose if they are a
dual agent (representing both buyer and seller in a transaction) or a designated agent
(represent either the buyer or seller depending on state law), or they are a limited representative
(will provide only certain duties in the transaction per state law).
#2: Agents must openly acknowledge to clients any personal interest they might have in any
transaction prior to showing a property; they must acknowledge any personal relationships
involved. Ex: Agent says, “I want to disclose to you before we look at it, that this property
belongs to is my brother and my sister in-law is his agent.”
#3: The Agent will not allow anyone that is not pre-authorized by the owner, to access the
property of the client.
#4: Never overstate benefits or attributes of a property or opportun.
a brief explanation of the effect of Apartheid in South Africa. Prov.docxsodhi3
a brief explanation of the effect of Apartheid in South Africa. Provide two specific examples that demonstrate how people adapted. Finally explain the impact and implications of the changes we have seen in recent years. Cite specific cases. Your original post must be no less than 600 words.
.
A 32-year-old female presents to the ED with a chief complaint of fe.docxsodhi3
A 32-year-old female presents to the ED with a chief complaint of fever, chills, nausea, vomiting, and vaginal discharge. She states these symptoms started about 3 days ago, but she thought she had the flu. She has begun to have LLQ pain and notes bilateral lower back pain. She denies dysuria, foul-smelling urine, or frequency. States she is married and has sexual intercourse with her husband. PMH negative.
Labs: CBC-WBC 18, Hgb 16, Hct 44, Plat 325, Neuts & Lymphs, sed rate 46 mm/hr, C-reactive protein 67 mg/L CMP wnl
Vital signs T 103.2 F Pulse 120 Resp 22 and PaO2
99% on room air. Cardio-respiratory exam WNL with the exception of tachycardia but no murmurs, rubs, clicks, or gallops. Abdominal exam + for LLQ pain on deep palpation but no rebound or rigidity. Pelvic exam demonstrates copious foul-smelling green drainage with reddened cervix and + bilateral adenexal tenderness. + chandelier sign. Wet prep in ER + clue cells and gram stain in ER + gram negative diplococci.
Develop a 1- to 2-page case study analysis, examining the patient symptoms presented in the case study. Be sure to address the following as it relates to the case you were assigned (omit section that does not pertain to your case, faculty will give full points for that section).
The sections that you are to omit are for the above case study are: 1. Explain why prostatitis and infection happen. Also explain the causes of systemic reaction, 2. Explain why a patient would need a splenectomy after a diagnosis of ITP, and 3. Explain anemia and the different kinds of anemia (i.e., micro and macrocytic).
In your Case Study Analysis related to the scenario provided, explain the following:
The factors that affect fertility (STDs).
Why inflammatory markers rise in STD/PID.
Why prostatitis and infection happens. Also explain the causes of systemic reaction.
Why a patient would need a splenectomy after a diagnosis of ITP.
Anemia and the different kinds of anemia (i.e., micro and macrocytic).
PLEASE ANSWER IN DETAIL ALL OF THE ABOVE
.
A 4 years old is brought to the clinic by his parents with abdominal.docxsodhi3
A 4 years old is brought to the clinic by his parents with abdominal pain and a poor appetite. His mother states, “He cries when I put him on the toilet.”
1. What other assessment information would you obtain?
2. What interventions may be necessary for this child?
3. What education may be necessary for this child and family?
Your responses must be at least 150 words total.
.
A 19-year-old male complains of burning sometimes, when I pee.”.docxsodhi3
A 19-year-old male complains of “burning sometimes, when I pee.” He is sexually active and denies using any contraceptive method. He denies other symptoms, significant history, or allergies.
From the information provided, list your differential diagnoses in the order of “most likely” to “possible but unlikely.”
.
A 34-year-old trauma victim, the Victor, is unconscious and on a.docxsodhi3
A 34-year-old trauma victim, the Victor, is unconscious and on a ventilator. He was admitted yesterday, and his condition remains critical. His religious affiliation is unknown; however, he has a tattoo of a crucifix.
What can the nurse do to assess and integrate spirituality into Victor’s care? If the family is in another state what can the nurse do to integrate the family into the care?
Your initial post must include a minimum of 300 words and include proper grammar, punctuation, and reference(s).
.
A 27-year-old Vietnamese woman in the delivery room with very st.docxsodhi3
A 27-year-old Vietnamese woman in the delivery room with very strong and closely spaced contractions. The baby was positioned a little high and there was some discussion of a possible c- section. Despite her difficulties, she cooperates with the doctor's instructions and labors in silence. The only signs of pain or discomfort were her look of concentration and her white knuckles.
· Should she be offered pain medication when she is not showing a high level of pain? Why or why not?
350 words
APA
.
A 25 year old male presents with chronic sinusitis and allergic .docxsodhi3
A 25 year old male presents with chronic sinusitis and allergic rhinitis.
Define adaptive vs. acquired immunity.
Discuss the genetic predisposition of allergens.
Describe the antigen-antibody response.
What is the pathology of sinusitis?
Expectations
Initial Post of Case Study:
Due: Saturday, 11:59 pm PT
Length: A minimum of 250 words, not including references
Citations: At least one high-level scholarly reference in APA from within the last 5 years
Peer Responses:
Due: Monday, 11:59 pm PT
Number: A Minimum of 2 to Peer Posts, at least one on a different day than the main post
Length: A minimum of 150 words per post, not including references
Citations: At least one high-level scholarly reference in APA per post from within the last 5 years
Discussion: Respond to Posts in Your Own Thread
.
A 500-700 word APA formatted PaperInclude 2 sources on your re.docxsodhi3
A 500-700 word APA formatted Paper
Include 2 sources on your reference page in addition to your textbook "
We the People
."
Select one issue area: CIVIL RIGHTS
Research which interest groups represent your issue area
Examine the membership and benefits of groups
Provide data on how much groups contribute to politicians
Discuss legislation the groups helped influence
Include reference page
Submit
your summary in APA format clicking on the assignment in Canvas and uploading your document. Be sure whichever assignment version you choose has an introduction, clear focus, conclusion, and references. Include a reference page for the video clip if that’s what you decide to prepare.
.
A 65-year-old obese African American male patient presents to his HC.docxsodhi3
A 65-year-old obese African American male patient presents to his HCP with crampy left lower quadrant pain, constipation, and fevers to 101˚ F. He has had multiple episodes like this one over the past 15 years and they always responded to bowel rest and oral antibiotics. He has refused to have the recommended colonoscopy even with his history of chronic inflammatory bowel disease (diverticulitis), sedentary lifestyle, and diet lacking in fiber. His paternal grandfather died of colon cancer back in the 1950s as well. He finally underwent colonoscopy after his acute diverticulitis resolved. Colonoscopy revealed multiple polyps that were retrieved, and the pathology was positive for adenocarcinoma of the colon.
Develop a 1- to 2-page case study analysis in which you:
Explain why you think the patient presented the symptoms described.
Identify the genes that may be associated with the development of the disease.
Explain the process of immunosuppression and the effect it has on body systems.
.
A 5-year-old male is brought to the primary care clinic by his m.docxsodhi3
A 5-year-old male is brought to the primary care clinic by his mother with a chief complaint of bilateral ear pain with acute onset that began “yesterday.” The mother states that the child has been crying frequently due to the pain. Ibuprofen has provided minimal relief. This morning, the child refused breakfast and appeared to be “getting worse.”
Vital signs at the clinic reveal HR 110 bpm, 28 respiratory rate, and tympanic temperature of 103.2 degrees F. Weight is 40.5 lbs. The mother reports no known allergies. The child has not been on antibiotics for the last year. The child does not have history of OM. The child is otherwise healthy without any other known health problems.
Physical examination reveals: Vital signsl HR 110 bpm, 28 respiratory rate, and tympanic temperature of 103.2 degrees F. Weight is 40.5 lbs. Bilateral TMs are bulging with severe erythematous. Pneumatic otoscopy reveals absent mobility. Ear canals are nomal.
After your questioning and examination, you diagnose this child with bilateral Acute Otitis Media.
.
92 S C I E N T I F I C A M E R I C A N R e p r i n t e d f r.docxsodhi3
92 S C I E N T I F I C A M E R I C A N R e p r i n t e d f r o m t h e O c t o b e r 1 9 9 4 i s s u e
ome creators announce their inventions with grand
éclat. God proclaimed, “Fiat lux,” and then flooded
his new universe with brightness. Others bring forth
great discoveries in a modest guise, as did Charles
Darwin in defining his new mechanism of evolu-
tionary causality in 1859: “I have called this principle, by which
each slight variation, if useful, is preserved, by the term Natur-
al Selection.”
Natural selection is an immensely powerful yet beautifully
simple theory that has held up remarkably well, under intense
and unrelenting scrutiny and testing, for 135 years. In essence,
natural selection locates the mechanism of evolutionary change
in a “struggle” among organisms for reproductive success, lead-
ing to improved fit of populations to changing environments.
(Struggle is often a metaphorical description and need not be
viewed as overt combat, guns blazing. Tactics for reproductive
success include a variety of nonmartial activities such as earlier
and more frequent mating or better cooperation with partners
in raising offspring.) Natural selection is therefore a principle of
local adaptation, not of general advance or progress.
Yet powerful though the principle may be, natural selection
is not the only cause of evolutionary change (and may, in many
cases, be overshadowed by other forces). This point needs em-
phasis because the standard misapplication of evolutionary the-
ory assumes that biological explanation may be equated with
devising accounts, often speculative and conjectural in practice,
about the adaptive value of any given feature in its original en-
vironment (human aggression as good for hunting, music and
religion as good for tribal cohesion, for example). Darwin him-
self strongly emphasized the multifactorial nature of evolu-
tionary change and warned against too exclusive a reliance on
natural selection, by placing the following statement in a max-
imally conspicuous place at the very end of his introduction: “I
am convinced that Natural Selection has been the most impor-
tant, but not the exclusive, means of modification.”
Reality versus Conceit
N A T U R A L S E L E C T I O N is not fully sufficient to explain evo-
lutionary change for two major reasons. First, many other caus-
es are powerful, particularly at levels of biological organization
both above and below the traditional Darwinian focus on or-
ganisms and their struggles for reproductive success. At the low-
est level of substitution in individual base pairs of DNA, change
is often effectively neutral and therefore random. At higher lev-
els, involving entire species or faunas, punctuated equilibrium
can produce evolutionary trends by selection of species based
on their rates of origin and extirpation, whereas mass extinc-
tions wipe out substantial parts of biotas for reasons unrelat-
ed to adaptive struggles of constituent species in “normal”
t.
a 100 words to respond to each question. Please be sure to add a que.docxsodhi3
a 100 words to respond to each question. Please be sure to add a question and answer a fellow student's question.
Q1. Mead argues that most human understanding of the "self" of animals is fallacious. What is his argument, please explain.
Q2. What does Lacan mean by the subject's assumption of the imago in the short excerpt from the Mirror Stage?
.
A 12,000 word final dissertation for Masters in Education project. .docxsodhi3
A 12,000 word final dissertation for Master's in Education project. A UK L7 writing.
Submitting the dissertation
The dissertation will be submitted online via
blackboard.
Presentation Style
Your research project needs to be clearly presented:
·
The front page should include your
name, project title (around 15 words), your supervisor’s name, the date it
was completed;
·
Work should be presented single
sided, in Arial, minimum font size 11 and be one and a half spaced;
·
A contents page detailing the section
and any tables/charts should be included;
·
Any quotes of less than 12 words
should be identified by quotation marks and kept as part of the paragraph text;
·
Quotes of 12 words and above should
be separated out from the text, indented on the left and right and be displayed
in italics (no quotation marks required);
·
All tables and charts should be
numbered appropriately and have a title;
·
Each section of your project should
be started on a new page;
·
All pages should be numbered;
·
Each section should be numbered (e.g.
1. Introduction) and any charts/graphs within the section should be numbered
accordingly. For example if you are writing about something in section 4.1 (the
first sub-section) then the first chart or graph would be 4.11. So charts and
graphs (if included) are numbered according to the section/sub-section.
Word limit
The project should be written up in
no more than 12,000
words
. This includes everything except the reference list, any appendices
and acknowledgements.
A
final checklist:
1.
Does
your abstract say succinctly what the project set out to do and what has been
found?
2.
Does
your contents page signpost chapter subheadings as well as chapter headings?
3.
Has
your introduction made clear the sub questions/objectives you are addressing in
this enquiry
4.
Is
a framework presented in your lit review chapter and a methodological approach
presented in your methodology chapter, and is it clear how this framework and
methodology inform your data collection, presentation of findings and
discussion and reflections? Have you discussed your positionality?
5.
Does
your discussion chapter relate closely to the data in your results chapter and
tie back to the literature in your literature review?
6.
Have
you answered your research questions?
7.
Have
you carefully considered any ethical implications of your research?
8.
Have
you included a signed, anonymised ethics form in the appendix?
9.
Does
your conclusion summarise what has been found out about the questions you set
yourself in your introduction?
10.
Have you kept to the 12,000 word
limit?
11.
Have you met
all
the assessment criteria?
M
odule
Bibliogr
a
p
h
y
Compulsory
reading:
B
r
y
m
an
,
A
.
(
20
1
6
)
.
S
o
ci
a
l
r
e
s
ea
r
ch
m
e
t
h
o
d
s
(
5
t
h
e
d
.
)
.O
x
f
o
rd
:
O
x
f
o
r
d
U
n
i
v
e
r
sity
P
r
e
ss.
Further optional reading
:
A
l
de
r
s
o
n
,
P
.
&
M
o
rr
o
w
,
V
.
(2
011
)
.
T
h
.
9/18/19
1
ISMM1-UC 752:
SYSTEMS ANALYSIS
Fall 2019 – Lecture 3
Instructor: Dr. Antonios Saravanos
Incremental Model
• Development and delivery of
functionality occurs in increments
• Works well when requirements are
known beforehand
• Projects are broken down into sub-
projects
Source: Project Management for IT-Related Projects (p.
18)
2
9/18/19
2
Incremental Cycle
Incremental Model
9/18/19
3
Iterative Model
• Ideal for situations where not all requirements are
known up front
• Need for development to begin as soon as possible
Source: Project Management for IT-Related Projects (p. 19)
5
Iterative Cycle
9/18/19
4
Iterative Model
Incremental vs. Iterative
• Incremental fundamentally means
add onto. Incremental development
helps you improve your process.
• Iterative fundamentally means re-
do. Iterative development helps you
improve your product.
9/18/19
5
• Is iterative and incremental the
same thing?
Incremental vs. Iterative
Source: http://www.applitude.se/images/inc_vs_ite.png
10
9/18/19
6
Iterative and Incremental Combined
A Simple Software Development Method
• Initial Planning
• Design
• Implementation
• Testing
Source: Making Things Happen: Mastering Project Management (p. 30)
12
n
9/18/19
7
Alistair Cockburn
• What’s Alistair’s take on Iterative vs. Incremental?
Incremental vs. Iterative
• in incremental development, you do each of those
activities multiple times … that is, you go around the
requirements – design – programming – testing –
integration – delivery cycle multiple times. You
“iterate” through that cycle multiple times. (“iterate” –
get it? sigh…)
• in iterative development, you also do each of those
activities multiple times … you go around the
requirements – design – programming – testing –
integration – delivery cycle multiple times. You
“iterate” through that cycle multiple times. By Gummy!
Both of those are “iterative” development! WOW!
9/18/19
8
Incremental vs. Iterative (cont’d)
• Of course, the $200,000 question is,
do you repeat the cycle “on the same
part of the system you just got done
with” or “on a new part of the
system”? How you answer that
question yields very different results
on what happens next on your
project.
Roles
• Product Owner (Business)
– Represents the customer
– Controls the product backlog
– Signs off on deliverables
• The Scrum Master
– Ensures scrum values are understood and kept
– Tracks progress and finds ways to overcome obstacles
• The Development Team
– The people actually responsible for delivering the system
– Self-organizing unit
– Members of the team are generalists not specialists
• Cross functional (Each member of the team knows all aspects of the
product that is being developed)
16
9/18/19
9
The Agile System Development Methodology
17
Manifesto for Agile Software Development
18
9/18/19
10
Manifesto for Agile Software Development
Source: http://www.applitude.se/images/inc_vs_i.
96 Young Scholars in WritingFeminist Figures or Damsel.docxsodhi3
96 | Young Scholars in Writing
Feminist Figures or Damsels in Distress?
The Media’s Gendered Misrepresentation
of Disney Princesses
Isabelle Gill | University of Central Florida
A gender bias seems to exist when discussing Disney princesses in entertainment media that could have
significant consequences for girls who admire these heroines. Prior research and my own extensions have
shown that modern princesses display almost equal amounts of masculine and feminine qualities; how-
ever, my research on film reviews shows an inaccurate representation of these qualities. These media
perpetuate sexist ideals for women in society by including traditionally feminine vocabulary, degrading
physical descriptions, and inaccuracies about the films, as well as syntax and critiques that trivialize the
heroines’ accomplishments and suggest the characters are not empowered enough. The reviews also
encourage unhealthy competition between the princesses and devote significantly more words to these
negative trends than to positive discussions. These patterns result in the depiction of the princesses as
more stereotypically feminine and weak than is indicated by the films themselves, which hinders the cre-
ation of role models for girls.
Despite significant strides women have made
toward combatting sexism in American
society, news and entertainment media rep-
resentations of women continue to be one of
the many obstacles left before reaching
equality. Numerous studies have identified
gender bias in the ways media represent
women (Fink and Kensicki; Niven and
Zilber; Shacar; Wood). Media tend to favor
representations of women who are “tradi-
tionally feminine” as well as not “too able,
too powerful, or too confident,” over more
complex representations (Wood 33). For
example, research by Janet Fink and Linda
Jean Kensicki shows that when media aimed
at both men and women discuss female ath-
letes, their focus is on sex appeal, fashion,
and family rather than athletic accomplish-
ment. Female scientists as well as female
members of Congress also fall victim to this
trend. Interviews with male scientists often
portray them as primarily professionals
while interviews with female scientists tend
to reference their professionalism while high-
lighting domesticity and family life (Shacar).
Similarly, media descriptions of the female
members of Congress focus on domestic
issues even though the congresswomen por-
tray themselves as having diverse interests
(Niven and Zilber). In sum, biased, gendered
representations of women are common in
various forms of media.
Media misrepresentation of women in
these ways can lead to significant social
consequences, such as reinforcing anti-
quated gender roles and diminishing the
perception of women’s impact on society
(England, Descartes, and Collier-Meek;
Fink and Kensicki; Graves; Niven and
Zilber; Shacar; Wood). Since media are
Gill | 97
Gill | 97
likely one of the most p.
How to Add Chatter in the odoo 17 ERP ModuleCeline George
In Odoo, the chatter is like a chat tool that helps you work together on records. You can leave notes and track things, making it easier to talk with your team and partners. Inside chatter, all communication history, activity, and changes will be displayed.
বাংলাদেশের অর্থনৈতিক সমীক্ষা ২০২৪ [Bangladesh Economic Review 2024 Bangla.pdf] কম্পিউটার , ট্যাব ও স্মার্ট ফোন ভার্সন সহ সম্পূর্ণ বাংলা ই-বুক বা pdf বই " সুচিপত্র ...বুকমার্ক মেনু 🔖 ও হাইপার লিংক মেনু 📝👆 যুক্ত ..
আমাদের সবার জন্য খুব খুব গুরুত্বপূর্ণ একটি বই ..বিসিএস, ব্যাংক, ইউনিভার্সিটি ভর্তি ও যে কোন প্রতিযোগিতা মূলক পরীক্ষার জন্য এর খুব ইম্পরট্যান্ট একটি বিষয় ...তাছাড়া বাংলাদেশের সাম্প্রতিক যে কোন ডাটা বা তথ্য এই বইতে পাবেন ...
তাই একজন নাগরিক হিসাবে এই তথ্য গুলো আপনার জানা প্রয়োজন ...।
বিসিএস ও ব্যাংক এর লিখিত পরীক্ষা ...+এছাড়া মাধ্যমিক ও উচ্চমাধ্যমিকের স্টুডেন্টদের জন্য অনেক কাজে আসবে ...
Exploiting Artificial Intelligence for Empowering Researchers and Faculty, In...Dr. Vinod Kumar Kanvaria
Exploiting Artificial Intelligence for Empowering Researchers and Faculty,
International FDP on Fundamentals of Research in Social Sciences
at Integral University, Lucknow, 06.06.2024
By Dr. Vinod Kumar Kanvaria
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
A workshop hosted by the South African Journal of Science aimed at postgraduate students and early career researchers with little or no experience in writing and publishing journal articles.
This slide is special for master students (MIBS & MIFB) in UUM. Also useful for readers who are interested in the topic of contemporary Islamic banking.
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
Assessment and Planning in Educational technology.pptxKavitha Krishnan
In an education system, it is understood that assessment is only for the students, but on the other hand, the Assessment of teachers is also an important aspect of the education system that ensures teachers are providing high-quality instruction to students. The assessment process can be used to provide feedback and support for professional development, to inform decisions about teacher retention or promotion, or to evaluate teacher effectiveness for accountability purposes.
The simplified electron and muon model, Oscillating Spacetime: The Foundation...RitikBhardwaj56
Discover the Simplified Electron and Muon Model: A New Wave-Based Approach to Understanding Particles delves into a groundbreaking theory that presents electrons and muons as rotating soliton waves within oscillating spacetime. Geared towards students, researchers, and science buffs, this book breaks down complex ideas into simple explanations. It covers topics such as electron waves, temporal dynamics, and the implications of this model on particle physics. With clear illustrations and easy-to-follow explanations, readers will gain a new outlook on the universe's fundamental nature.
it describes the bony anatomy including the femoral head , acetabulum, labrum . also discusses the capsule , ligaments . muscle that act on the hip joint and the range of motion are outlined. factors affecting hip joint stability and weight transmission through the joint are summarized.
Required ResourcesText· Botkin, D. B., & Keller, E. A. (.docx
1. Required Resources
Text
· Botkin, D. B., & Keller, E. A. (2014). Environmental science:
Earth as a living planet (9th ed.). Hoboken, NJ: John Wiley &
Sons, Inc
· Chapter 4: The Big Picture: Systems of Change
· Chapter 6: Ecosystems: Concepts and Fundamentals
Multimedia
· Annenberg Learner. (n.d.). Unit 4: Ecosystems [Interactive
resource]. In The Habitable Planet. Retrieved from
http://www.learner.org/courses/envsci/unit/text.php?unit=4&sec
Num=0
Classics Theorists Notes
Classics Discussion
When talking the role of manager we are talking about Taylor,
Faole and Gulick.
· Wilsons Dichotomy (1887)
(NEED TO KNOW)
· Politics and Administration are SEPERATE
· Politics
· Purpose: Create Policy
· Involved: elected officials responsible for the creation of
policy
· Laws
· Ordinances
· Policy
· Administration (The Machine)
2. · Purpose: To implement policy
· Involved: Everyone who is employed by the government
agency including…
· Military
· First responders
· Social services
· Parks and rec, ect
· Even if we (administrators) do not agree with the law, we still
have to enforce it
Fredrick Taylor (talks about role of the manager)
-If nothing else, he was about EFFICIENCY
-All about standardizing the methods of business
-Consistency
-Management is the expert of the process
-The beginning of the white-collar workforce
-Created a science behind industrial work or any type of work
realistically
-Concerned more with the efficiency than care and respect
-Wanted to (and did) create replaceable labor
-Wanted to create an industrial utopia (great in theory, nearly
impossible in practice)
-His incentive was not to cut the piece rate for his workers but
to pay them more for their improved efficiency.
-This was not the norm of business operation
-Taylors Scientific Management method made up for the lack of
human efficiency
-He found a way to improve what was thought to be
nonimprovable
-Only worthy managers should be managers (Managers are not
to be lazy, or entitled, or dominant of thought over their
workers)
-The idea was that this scientific management could be applied
to all forms of life (school, government work, lifestyle, ect.)
Max Weber 1922 (Father of Bureaucracy) talks about:
3. organizational structure
-Six characteristics of Bureaucracy (more about how we manage
not how we govern)
1. Well defined formal hierarchy of command
2. Management by rules and regulations
3. Division of labor and work specialization
4. Managers should maintain an impersonal relationship with
their employees
5. Competence and not personality should be basis for job
appointment
6. Formal rules, regulation, procedures, decisions, and actions
by the organization and its members should be recorded in order
to preserve consistency and accountability.
Marry Parker Follett 1926 (Talks about leadership and
management style)
-Recognized the holistic nature of community and advanced the
idea of reciprocal relationships in understanding the dynamic
aspects of the individual in the relationship to others
-Advocated the principle of what she termed integration or
noncoercieve power.
-A forward thinker in conflict resolution
· There is a person involved in getting more work done with an
administration
· Working with a person gets more production out of a person
working with vs. working over them
· “Power with” rather than “power over”
There are some industries where Taylor works for that
environment
All of these theories are how managers should or could manage
their employees and work with them
Elton Mayo
· Hawthorne Effect
· A type of reactivity in which individuals modify or improve an
aspect of their behavior in response to their awareness of being
4. observed
· The novelty of increased attention could lead to temporary
increases in workers’ productivity
· Managers who understand informal ties among workers can
make decisions for management’s benefit
· People’s work performance is dependent on both social
relationships and job content
· The lighting with workers in a factory higher will higher
productivity and lower the lighting and higher productivity
therefore he drew off of Follet and find that there was
something else affecting their work
· Also found (researchers) people produce better if they think
somebody cares
· 1) the presence of the researcher can change behavior 2)
(pulling off of Follet) if we as managers pay attention and make
the employees feel like their views are important someone cares
then that increases productivity
We are just trying to figure out public admin in 1912
management
Then with Weber it more about what do we do with management
and how we implement management
Luther Gulick (1937)
· POSDCoRB (Talks about the role of managers)
· Planning
· Working out in broad outline
· Example “we are going into a digital social media method”
· What are we going to do in the future
· Organizing
· Establishing the formal factor
· Weber thinking “how we are going to do this” steps to get
there
· Staffing
· Follett or Taylor
· How do we decide to put which staff where
5. · Training falls under this
· Directing
· Then telling them what to do
· Coordinating
· Example reporters coordinate with photographers
· Reporting
· The manager going to their bosses after getting from their
subordinates what they’ve done and making sure that they are
dong their jobs
· Focus on the manager reporting up
· Budgeting
· Division/Coordination of work
· Workers should only have one boss
· Gulick focuses in at this point—management is management
not about the worker
· Takes a look on the role of the manager—focus on the
manager
· Back then there were workers and managers (white collar
workers and blue collar worker) you do what you do
Chester Barnard (1938)
· Functions of the Executive
· Stressed “soft” factors such as “communication” and “informal
processes” in organizations
· Weber views communication through the hierarchy
· There is something more different types of organizations and
communication formal and informal
· Seven Essential Rules (1-4)
· Channels of communication should be definite
· Everyone should know the channels of communication
· Everyone should have access to the formal channels of
communic1ation
· Lines of communication should be as short and direct as
possible
· There is someone sometimes in an informal sense that exists
as for example a person you go to when you want to get
6. something done—the informal channel of organization if you
want something done so you may go through both ways
· Example show M.A.S.H. where the clerk was always the
person to go if you want something done
· You see this form around the “water cooler” and you find out
who the person you go to if you want something done because
of those casual informal organization
· If the workers don’t feel like the higher ups will have their
backs they will break apart the formal organization—the bond
with the informal organization can come up and overcome the
formal organization by bonding together with the informal and
overthrowing
· Example “Ferguson Effect” and proactive police work is ideal
but the ferguson effect is that police officers don’t care about
doing that anymore being the nosy person and getting an idea of
the neighborhood so you will figure out when something is
off—but you don’t get paid or anything for doing that extra
work
· How much extra effort will put into a job if they feel like
management won’t have their back
· That informal communication and understanding
Abraham Maslow (1943)
· He wasn’t a business person or a public administration person,
he was a psychologist so he takes it from a very psychological
approach
· Page 118 in the classics book
· Levels of motivation
· Levels of need pyramid:
· Level 5 Self-actualization—after you have reached esteem
then and only then can move up to self-actualization
· Are you doing what you were meant to do?
· You may realize after going through everything else that you
may need to be doing something else on this earth—a
metaphysical sense, example mid-life crisis,
· Level 4 Esteem—after you have the love and belonging you
7. may go for the award or the medal or whatever
· Level 3 Love/Belonging—example if you have an employee
that you make feel loved and belonged to an organization
· Level 2 Safety—for example if your people are living in an
environment that is safe, living situations, a house that is safe,
an environment that is safe
· Maybe you can extrapolate that questions if your job is even
safe
· You will not be motivated by anything else if you don’t’ feel
safe
· Job security, physical safety, if you feel safe within the job,
working conditions, interpersonal relationships
· Level 1 Physiological—the base need that you cannot move up
the motivational ladder if first and foremost your physiological
needs are met—you need this done or else nothing else will be
done
· For example the first responders in new york—there is a place
for maslow and others where maslow doesn’t apply well in that
area
· Maslow says that once you overcome a level it cannot
motivate you anymore—the next level up can only motivate
you.
Douglas McGregor (1957)
These theories were written for the managers. Do you as a
manger fall into theory X or theory Y?
-Theory X
-Workers dislike working
-Avoid responsibility and need to be directed
-Have to be controlled, forced, and threatened to deliver what’s
needed
-Need to be supervised as every step, with controls put in place
-Need to be enticed to produce results otherwise there is no
ambition or incentive
-Theory Y
-Workers take responsibility and are motivated to fulfill the
8. goals they are given
-Seek and accept responsibility and do not need much direction
-Consider work as a natural part of life and solve work
problems imaginatively.
Herbert Simon (1946)
-Bounded Rationality
-Only going to look at a few options and chose what you like
the best. Not the same as rational choice where one looks at all
options and chooses the best for them.
-Satisficing (satisfied and sufficient)
-In order to talk about organizations, we need to talk about
decision-making.
Charles E. Lindblom (1959)
-The science of muddling through
-Incrementalism
-Trial and error (does this work? No but how about this?)
-Policy revolution is evolutionary, not revolutionary
Graham Allison (1979)
-Public and private leadership: They are fundamentally alike in
all unimportant respects
-Other than that we are different
-Public sector does what no one else wants to
-Public sector handles the wicked problems
Theories and History
Dr. Linda-Marie Sundstrom
9. Name / Where do you work
How far along are you in the MPPA Program
Other classes you’re taking this term
Have you ever lived or traveled outside the United States
What do you hope to get out of this class
Introductions
Articles of Confederation (1777)
Constitution (1787)
Constitution was signed in 1787, but ratified by New Hampshire
(9 of the 13 states) in 1788
The term in the video “republican” refers to a representative
republic form of government (elected representatives
representing the people) ruled by the constitution (as opposed to
a democracy), not the political party
Federalism
https://www.youtube.com/watch?v=bO7FQsCcbD8
13:03
Overview
Articles of the Constitution include
Article I – Legislative Branch
Article II – Executive Branch
Article III – Judicial Branch
10. Article IV – States Rights
Article V – Amendment Process
Article VI – Constitution is the Law of the Land
Article VII – Ratification
https://www.youtube.com/watch?v=GiahGIKTl00
(1:28)
Articles I, II, and III
Hamilton, Madison, Jay
https://www.youtube.com/watch?v=b9lCkWJ72yE&list=PLi3U-
nPPrbS5d-juhFwo3hTBso0gq2sUZ&index=45
(Start video at 2:20 mark)
Federalist Papers (1787-1788)
First 10 Amendments to the Constitution
https://www.youtube.com/watch?v=yYEfLm5dLMQ
(3 minutes)
Bill of Rights
2/3 of both houses
3/4 of all states
https://www.youtube.com/watch?v=epuwfzEJ4PU&list=PLi3U-
nPPrbS5d-juhFwo3hTBso0gq2sUZ&index=41
(4:55)
11. Constitutional Amendments
https://www.youtube.com/watch?v=J0gosGXSgsI
Federalism
President Andrew Jackson – Spoils System
President Garfield shot by supporter
Pendleton Act
Signed by President Chester A. Arthur
Spoils System/Merit System
Wilson’s Dichotomy (1887)
Politics/Administration Dichotomy
Politics
Purpose: To create policy
Involved: Elected Officials responsible for the creation of
policy
Laws
Ordinances
Policy
Administration
Purpose: To implement policy
Involved: Everyone who is employed by a government agency
12. including
Military
First responders
Social services
Parks and rec, etc.
Scientific Management
One Best Way
Frederick Winslow Taylor (1912)
Henri Fayol (1916)
14 Principles of Management
Division of Labor
Authority
Discipline
Unity of Command
Unity of Direction
Subordination
Remuneration
Centralization
Scalar Chain
Order
Equity
Stability of Tenure of Personnel
Initiative
Esprit de Corps
13. He did not like the fact that employees were more loyal to their
bosses then to their organizations which therefore created a
family-like structure.
He instead believed in a more formal and rigid structure of
organization known as bureaucracy.
Bureaucracy is a non-personal view of organizations
Formal structure that has rules, and formal legitimate authority
It has characteristics of appropriate management practices.
Max Weber (1922)
Six Characteristics of Bureaucracy
Well defined formal hierarchy of command
Management by rules and regulation
Division of labor and work specialization
Managers should maintain an impersonal relationship with their
employees
Competence and not personality should be basis for job
appointment
Formal rules, regulations, procedures, decisions and actions by
the organizations and its members should be recorded in order
to preserve consistency and accountability
Max Weber (cont’d)
14. She recognized the holistic nature of community and advanced
the idea of "reciprocal relationships" in understanding the
dynamic aspects of the individual in relationship to others.
Advocated the principle of what she termed "integration," or
noncoercive power-sharing based on the use of her concept of
"power with" rather than "power over.“
https://www.youtube.com/watch?v=qTgnhatFvPc
(4:39 History)
Mary Parker Follett (1926)
Hawthorne Effect
A type of reactivity in which individuals modify or improve an
aspect of their behavior in response to their awareness of being
observed
The novelty of increased attention could lead to temporary
increases in workers' productivity.
Managers who understand informal ties among workers can
make decisions for management's benefit
People's work performance is dependent on both social
relationships and job content.
Elton Mayo (1920s)
Brownlow, Merriam, & Gulick recommended changes to the
Executive Office of the President including:
Creating aides to the President in order to deal with the
administrative tasks assigned to the President.
The President should have direct control over the administrative
departments.
15. The managerial agencies - The Civil Service Administration, the
Bureau of the Budget, and the National Resources Board -
should be part of the Executive Office.
The Reorganization Act of 1939 incorporated only two of the
recommendations.
The most important results of the actions taken by Roosevelt
were the creation of the Executive Office of the President and
the creation of a group of six executive level assistants.
Brownlow Commission 1937
POSDCoRB
Planning
Organizing
Staffing
Directing
Coordinating
Reporting
Budgeting
Division/Coordination of work
Workers should only have one boss
Gulick (1937)
Functions of the Executive
Stressed "soft" factors such as "communication" and "informal
processes“ in organizations
Seven Essential Rules (1-4)
Channels of communication should be definite
16. Everyone should know the channels of communication
Everyone should have access to the formal channels of
communication
Lines of communication should be as short and direct as
possible
Chester Barnard (1938)
Competence of persons serving as communication centers
should be adequate
The line of communication should not be interrupted when
organization is functioning
Every communication should be authenticated
Organizations endure, however, in proportion to the breadth of
the morality by which they are governed
The endurance of an organization depends upon the quality of
leadership, and that quality derives from the breadth of the
morality upon which it rests
Chester Barnard (7 Rules cont’d)
Abraham Maslow (1943)
17. Bounded Rationality
Satisficing
In order to talk about organizations, we need to talk about
decision making (Simon)
https://www.youtube.com/watch?v=ErnWbP_Wztk
Herbert Simon (1946)
Waldo challenged mainstream scholars' view of public
administration as a value-free, non-partisan social science that
promised to make government more efficient and effective.
Dwight Waldo (1948)
Theory X
Workers dislike working.
Avoid responsibility and need to be directed.
Have to be controlled, forced, and threatened to deliver what's
needed.
Need to be supervised at every step, with controls put in place.
Need to be enticed to produce results; otherwise they have no
ambition or incentive to work.
Douglas McGregor (1957)
18. Theory Y
Workers take responsibility and are motivated to fulfill the
goals they are given
Seek and accept responsibility and do not need much direction
Consider work as a natural part of life and solve work problems
imaginatively
McGregor (Cont’d)
The science of muddling through
Incrementalism
Policy change is evolutionary, not revolutionary
Charles E. Lindblom (1959)
New Public Management (NPM) is the label given to a series of
reforms from the 1980s onwards, to improve the efficiency and
performance of western governments and/or public sector
organizations.
New Public Management (1980s)
Strengthening steering functions
Devolving authority, providing flexibility
Ensuring performance, control and accountability
19. Improving the management of human resources
Optimizing information technology
Improving the quality of regulation
Providing responsive service
Developing competition and choice
https://www.youtube.com/watch?v=C-3-lEEHvzc
EU Based
https://www.youtube.com/watch?v=uLHbUF7dADA
R. Swanson - Start at 1 minute mark (1:15)
NPM - 8 Aspects to NPM
Public and private leadership: Are they fundamentally alike in
all unimportant respects
Graham Allison (1979)
The New Public Service
Serving, Not Steering
A new model of governance that stresses the need to engage
citizens in governance of their communities
Denhardt & Denhardt (2007)
In order to talk about organizations, we need to talk about
decision making (Barnard, Simon)
20. Rational Choice
Bounded Rationality
Satisficing
Herbert Simon
https://www.youtube.com/watch?v=ErnWbP_Wztk
Garbage Can Theory
Cohen March and Olsen, 1972
https://www.youtube.com/watch?v=raTM7OSSQ8k
Charles Lindblom
The Science of Muddling Through
Incrementalism
Decision Making Theories
Elite Theory
Group Theory
Rational Choice Theory
Institutional Theory
Political Systems Theory
Agenda Setting
John Kingdon’s Three Streams (1984)
Problem Identification
More of a crisis, more likely it will get on the agenda
Policy Alternative Development
Politics
Swings of national mood to face the problem
Three streams work largely independent of each other
21. When these three streams converge, the more likely it will get
on the agenda (a policy window is open for a very short time)
Policy Entrepreneurs need to seize the opportunity because the
window will close quickly
Agenda Setting
Problems with no easy solution (e.g., poverty)
Solution
s to wicked problems are not right or wrong, or good or bad
No immediate or ultimate test for solutions
Wicked problems have no given alternative solutions.
Every wicked problem can be considered to be a symptom of
another problem.
The existence of a wicked problem can be explained in
numerous ways.
The explanation determines the nature of the problem's
resolution
Rittel and Webber (1973)
Wicked Problems (Rittel & Webber)
22. Efficiency vs. Effectiveness
Great Man Theory
Trait Theory
Skills Theory
Style Theory
Situational Leadership
Contingency Theory
Transactional Leadership
Transformational Leadership
Servant Leadership
https://www.youtube.com/watch?v=XKUPDUDOBVo
Leadership Theories
23. V. O. Key (1940)
Lack of Budgetary Theory
Key tried to address the issue of public budgeting not having a
theory of its own by offering a microeconomic solution to the
problem, one that would increase allocative efficiency of
government.
Line Item Budget
Zero Based Budget
Incremental Budget
Budgeting Concepts
Objective Responsibilities (to others)
To superiors, subordinates, legislation, citizens
Subjective Responsibilities (to oneself)
Beliefs, values and feelings
Role Conflict
Authority Conflict
External Controls (Legislation, Codes of Conduct)
Internal Controls (Standards, Values, Beliefs)
24. Deontological (Moral Duties)
Teleological (Consequences Play a Role)
Ethics Theories
Questions?
Chapter 4: Study Questions 1, 3, and 4
!. What is the difference between positive and negative
feedback in systems? Provide an example of each.
3. Why is the idea of equilibrium in systems somewhat
misleading in regard to environmental questions? Is it ever
possible to establish a balance of nature?
4. Why is the average residence time important in the study of
the environment?
Chapter 6: Study Questions 1, 3, and 5
25. 1.Farming has been described as managing land to keep it in an
early stage of succession. What does this mean, and how is it
achieved?
2. What is the difference between an ecosystem and an
ecological community?
5. Based on the discussion in this chapter, would you ex- pect a
highly polluted ecosystem to have many species or few species?
Is our species a keystone species? Explain.
Total Possible Score: 7.00
CH 4: Question 1: Explain the Differences Between Positive
and Negative Feedback in a System and Provides an Example
Total: 1.00
Distinguished - Comprehensively explains the differences
between positive and negative feedback in a system, providing
detailed and specific examples.
CH 4: Question 3: Explains Why the Idea of Equilibrium in
Systems is Somewhat Misleading in Regard to Environmental
Questions and Discusses the Possibility to Establish a Balance
in Nature
Total: 1.00
Distinguished - Comprehensively explains why the idea of
equilibrium in systems is somewhat misleading in regard to
26. environmental questions and thoroughly discusses whether it is
possible to establish balance in nature.
CH 4: Question 4: Explain Why the Average Residence Time is
Important to the Study of the Environment
Total: 1.00
Distinguished - Comprehensively explains the importance of
average residence time in studying the environment.
CH 6: Question 1 Farming Has Been Described as Managing the
Land to Keep it in an Early Stage of Succession. Explains What
This Means and How is it Achieved
Total: 1.00
Distinguished - Comprehensively describes the meaning of
farming to keep the land in an early stage of succession and
thoroughly explains what this means and how this is achieved.
CH 6: Question 3 Explains the Difference Between an
Ecosystem and an Ecological Community
Total: 1.00
Distinguished - Thoroughly explains the difference between an
ecosystem and an ecological community.
CH 6: Question 5 Explain Whether a Highly Polluted Ecosystem
Would Have Many Species or a Few Species. Explain Whether
our Species is a Keystone Species
Total: 1.00
Distinguished - Comprehensively and effectively explains
whether a highly polluted system would have few or many
27. species, and thoroughly explains whether humans are a keystone
species.
Written Communication: Control of Syntax and Mechanics
Total: 0.80
Distinguished - Displays meticulous comprehension and
organization of syntax and mechanics, such as spelling and
grammar. Written work contains no errors, and is very easy to
understand.
APA Formatting
Total: 0.20
Distinguished - Accurately uses APA formatting consistently
throughout the paper, title page, and reference page.
CHAPTER 6
Botkin, D. B., & Keller, E. A. (2014). Environmental science:
Earth as a living planet (9th ed.). Hoboken, NJ: John Wiley &
Sons, Inc
· Chapter 6: Ecosystems: Concepts and Fundamentals
6.1 the Ecosystem: Sustaining Life on Earth
We tend to associate life with individual organisms, for the
obvious reason that it is individuals that are alive. But
sustaining life on Earth requires more than individuals or even
28. single populations or species. Life is sustained by the
interactions of many organisms functioning together, interacting
through their physical and chemical environ- ments. We call
this an ecosystem. Sustained life on Earth, then, is a
characteristic of ecosystems, not of individual organisms or
populations. As the opening case study about Lyme disease
illustrates, to understand important environmental issues—such
as controlling undesirable species; conserving endangered
species; sustaining renew- able resources; and minimizing the
effects of toxic sub- stances—we must understand the basic
characteristics of ecosystems.
Basic Characteristics of Ecosystems
Ecosystems have several fundamental characteristics, which we
can group as structure and processes.
Ecosystem Structure
An ecosystem has two major parts: nonliving and liv- ing. The
nonliving part is the physical-chemical environ- ment, including
the local atmosphere, water, and mineral soil (on land) or other
substrate (in water). The living part, called the ecological
community, is the set of spe- cies interacting within the
ecosystem.
Ecosystem Functions and Processes
Two basic kinds of processes (sometimes referred to as
ecosystem functions) must occur in an ecosystem: a cycling of
chemical elements and a flow of energy. These processes are
29. necessary for all life, but no single species can carry out all
necessary chemical cycling and energy flow alone. That is why
we said that sustained life on Earth is a characteristic of
ecosystems, not of individuals or populations. At its most basic,
an ecosystem consists of several species and a fluid medium—
air, water, or both (Figure 6.4). Ecosystem energy flow places a
fun- damental limit on the abundance of life. Energy flow is a
difficult subject, which we will discuss in Section 6.4.
Ecosystem chemical cycling is complex as well, and for that
reason we have devoted a separate chapter (Chapter 7) to
chemical cycling within ecosystems and throughoutthe entire
Earth’s biosphere. Briefly, 21 chemical elements are required
by at least some form of life, and each chemi- cal element
required for growth and reproduction must be available to each
organism at the right time, in the right amount, and in the right
ratio relative to other ele- ments. These chemical elements must
also be recycled— converted to a reusable form: Wastes are
converted into food, which is converted into wastes, which must
be con- verted once again into food, with the cycling going on
indefinitely if the ecosystem is to remain viable.
For recycling of chemical elements to take place, sev- eral
species must interact. In the presence of light, green plants,
algae, and photosynthetic bacteria produce sugar from carbon
dioxide and water. From sugar and inorganic compounds, they
make many organic compounds, in- cluding proteins and woody
30. tissue. But no green plant, algae, or photosynthetic bacteria can
decompose woody tissue back to its original inorganic
compounds. Other forms of life—primarily bacteria and fungi—
can decom- pose organic matter. But they cannot produce their
own food; instead, they obtain energy and chemical nutrition
from the dead tissues on which they feed. In an ecosystem,
chemical elements recycle, but energy flows one way, into and
out of the system, with a small fraction of it stored, as we will
discuss later in this chapter.
To repeat: Theoretically, at its simplest, an ecosystem consists
of at least one species that produces its own food from
inorganic compounds in its environment and anoth- er species
that decomposes the wastes of the first species, plus a fluid
medium—air, water, or both (Figure 6.4). But the reality is
never as simple as that.
6.2 Ecological Communities
and Food Chains
In practice, ecologists define the term ecological commu- nity
in two ways. One method defines the community as a set of
interacting species found in the same place and functioning
together, thus enabling life to persist. That is essentially the
definition we used earlier. A problem with this definition is that
it is often difficult in practice to know the entire set of
interacting species. Ecologists therefore may use a practical or
an operational definition, in which the community consists of
31. all the species found in an area, whether or not they are known
to interact. Animals in different cages in a zoo could be called a
com- munity according to this definition.
One way that individuals in a community interact is by feeding
on one another. Energy, chemical elements, and some
compounds are transferred from creature to creature along food
chains, the linkage of who feeds on whom. The more complex
linkages are called food webs. Ecologists group the organisms
in a food web into trophic levels. A trophic level (from the
Greek word trephein, meaning to nourish, thus the “nourishing
level”) consists of all organisms in a food web that are the same
number of feeding levels away from the original energy source.
The original source of energy in most ecosystems is the sun. In
other cases, it is the energy in certain inorganic compounds.
Green plants, algae, and certain bacteria produce sug- ars
through the process of photosynthesis, using only energy from
the sun, water (H2O), and carbon dioxide (CO2) from the local
environment. They are called auto- trophs, from the words auto
(self) and trephein (to nour- ish), thus “self-nourishing,” and
are grouped into the first trophic level. All other organisms are
called heterotrophs. Of these, herbivores—organisms that feed
on plants, al- gae, or photosynthetic bacteria—are members of
the sec- ond trophic level. Carnivores, or meat-eaters, that feed
directly on herbivores make up the third trophic level.
Carnivores that feed on third-level carnivores are in the fourth
32. trophic level, and so on. Decomposers, those that feed on dead
organic material, are classified in the highest trophic level in an
ecosystem.
Food chains and food webs are often quite complicat- ed and
thus not easy to analyze. For starters, the number of trophic
levels differs among ecosystems.
A Simple Ecosystem
One of the simplest natural ecosystems is a hot spring, such as
those found in 4geyser basins in Yellowstone National Park,
Wyoming. They are simple because few organisms can live in
these severe environments. In and near the center of a spring,
water is close to the boilingpoint, while at the edges, next to
soil and winter snow, water is much cooler. In addition, some
springs are very acidic and others are very alkaline; either
extreme makes a harsh environment.
Photosynthetic bacteria and algae make up the spring’s first
trophic level. In a typical alkaline hot spring, the hottest waters,
between 70° and 80°C (158–176°F), are colored bright yellow-
green by photosynthetic blue- green bacteria. One of the few
kinds of photosynthetic organisms that can survive at those
temperatures, these give the springs the striking appearance for
which they are famous (Figure 6.5). In slightly cooler waters,
50° to 60°C (122–140°F), thick mats of other kinds of bac- teria
and algae accumulate, some becoming 5 cm thick (Figures 6.5,
6.6).
33. The bacteria living in these hot springs became of spe- cial
interest in 1985 when an enzyme was isolated from one species
that allows “DNA fingerprinting,” a now ma- jor method in
molecular biology.5
Ephydrid flies make up the second (herbivore) tro- phic level.
Note that because the environment is so stress- ful, they are the
only genus on that entire trophic level, and they live only in the
cooler areas of the springs. One of these species, Ephydra
bruesi, lays bright orange-pink egg masses on stones and twigs
that project above the mat. These larvae feed on the bacteria
and algae.
The third (carnivore) trophic level is made up of a dolichopodid
fly, which feeds on the eggs and larvae of the herbivorous flies,
and dragonflies, wasps, spiders, tiger beetles, and one species
of bird, the killdeer, that feeds on the ephydrid flies. (Note that
the killdeer is a carnivore of the hot springs but also feeds
widely in other ecosystems. An interesting question, little
addressed in the ecological scientific literature, is how we
should list this partial mem- ber of the food web: Should there
be a separate category of “casual” members? What do you
think?)
In addition to their other predators, the herbi- vorous ephydrid
flies have parasites. One is a red mite thatfeeds on the flies’
eggs and travels by attaching itself to the adult flies. Another is
a small wasp that lays its eggs within the fly larvae. These are
34. also on the third trophic level.
Wastes and dead organisms of all trophic levels are fed on by
decomposers, which in the hot springs are primarily bacteria.
These form the fourth trophic level.
The entire hot-springs community of organisms—
photosynthetic bacteria and algae, herbivorous flies, car-
nivores, and decomposers—is maintained by two factors: (1)
sunlight, which provides usable energy for the organ- isms; and
(2) a constant flow of hot water, which provides a continual
new supply of chemical elements required for life and a habitat
in which the bacteria and algae can per- sist. (See A Closer
Look 6.1 and Figure 6.7 for another example of trophic levels
and keystone species.)
An Oceanic Food Chain
In oceans, food webs involve more species and tend to have
more trophic levels than they do in a terrestrial ecosystem. In a
typical pelagic (open-ocean) ecosystem (Figure 6.8),
microscopic single-cell planktonic algae and planktonic
photosynthetic bacteria are in the first trophic level. Small
invertebrates called zooplankton and some fish feed on the
algae and photosynthetic bacteria, forming the second trophic
level. Other fish and invertebrates feed on theseIn the abstract
or in extreme environments like a hot herbivores and form the
third trophic level. The great ba-spring, a diagram of a food web
and its trophic levels may leen whales filter seawater for food,
35. feeding primarily on small herbivorous zooplankton (mostly
crustaceans), and thus the baleen whales are also in the third
level. Some fish and marine mammals, such as killer whales,
feed on the predatory fish and form higher trophic levels.
Food Webs Can Be Complex: The Food Web of the Harp Seal
In the abstract or in extreme environments like a hot spring, a
diagram of a food web and its trophic levels may leen whales
filter seawater for food, feeding primarily onseem simple and
neat. In reality, however, most food webs are complex. One
reason for the complexity is that many creatures feed on several
trophic levels. For example, con- sider the food web of the harp
seal (Figure 6.9). This spe- cies is of special interest because
large numbers of the pups are harvested each year in Canada for
their fur, giving rise to widespread controversy over the humane
treatment of animals even though the species is not endangered
(there are more than 5 million harp seals.)6 This controversy is
one reason that the harp seal has been well studied, so we can
show its complex food web.6
The harp seal is shown at the fifth level. It feeds on flatfish
(fourth level), which feed on sand launces (third level), which
feed on euphausiids (second level), which feed on
phytoplankton (first level). But the harp seal actually feeds at
several trophic levels, from the second through the fourth. Thus,
it feeds on the prey of some of its prey and therefore competes
with some of its own prey.7 A species that feeds on several
36. trophic levels is typi- cally classified as belonging to the
trophic level above the highest level from which it feeds. Thus,
we place the harp seal on the fifth trophic level.
6.3 ecosystems as Systems
Ecosystems are open systems: Energy and matter flow into and
out of them (see Chapter 4). As we have said, an ecosystem is
the minimal entity that has the properties required to sustain
life. This implies that an ecosystem is real and important and
therefore that we should be able to find one easily. However,
ecosystems vary greatly in structural complexity and in the
clarity of their bound- aries. Sometimes their borders are well
defined, such as between a lake and the surrounding countryside
(Figure 6.11a). But sometimes the transition from one
ecosystem to another is gradual—for example, the transition
from deciduous to boreal forest on the slopes of Mount Wash-
ington, New Hampshire (Figure 6.11b), and in the subtle
gradations from grasslands to savannas in East Africa and from
boreal forest to tundra in the Far North, where the trees thin out
gradually and setting a boundary is difficult and usually
arbitrary.
A commonly used practical delineation of the bound- ary of an
ecosystem on land is the watershed. Within a watershed, all rain
that reaches the ground from any source flows out in one
stream. Topography (the lay of the land) determines the
watershed. When a watershed is used to define the boundaries
37. of an ecosystem, the ecosys- tem is unified in terms of chemical
cycling. Some classic experimental studies of ecosystems have
been conducted on forested watersheds in U.S. Forest Service
experimen- tal areas, including the Hubbard Brook experimental
for- est in New Hampshire (Figure 6.12) and the Andrews
experimental forest in Oregon. In other cases, the choice of an
ecosystem’s boundary may be arbitrary. For the purposes of
scientific analysis, this is okay as long as this boundary is used
consistently for any calculation of the exchange of chemicals
and energy and the migration of organisms. Let us repeat the
primary point: What all eco- systems have in common is not a
particular physical size or shape but the processes we have
mentioned—the flow of energy and the cycling of chemical
elements, which give ecosystems the ability to sustain life.
6.4 Biological production and Ecosystem Energy Flow
All life requires energy. Energy is the ability to do work, to
move matter. As anyone who has dieted knows, our weight is a
delicate balance between the energy we take in through our food
and the energy we use. What we do not use and do not pass on,
we store. Our use of energy, and whether we gain or lose
weight, follows the laws of physics. This is true not only for
people but also for all populations of living things, for all
ecological communi- ties and ecosystems, and for the entire
biosphere (which we defined in Chapter 4 as the planetary
system that in- cludes and sustains life, and that sometimes is
38. referred to loosely as the global ecosystem).
Ecosystem energy flow is the movement of energy through an
ecosystem from the external environment through a series of
organisms and back to the exter- nal environment. It is one of
the fundamental processes common to all ecosystems. Energy
enters an ecosystem by two pathways: Energy that is fixed by
organisms and moving through food webs within an ecosystem;
and heat energy that is transferred by air or water currents or by
convection through soils and sediments and warms living
things. For instance, when a warm air mass passes over a forest,
heat energy is transferred from the air to the land and to the
organisms.
Energy is a difficult and an abstract concept. When we buy
electricity, what are we buying? We cannot see it or feel it,
even if we have to pay for it. At first glance, and as we think
about it with our own diets, energy flow seems simple enough:
We take energy in and use it, just like machines do—our
automobiles, cell phones, and so on. But if we dig a little
deeper into this subject, we discover a philosophical
importance: We learn what distinguishes Earth’s life and life-
containing systems from the rest of the universe.
Although most of the time energy is invisible to us, with
infrared film we can see the differences between warm and cold
objects, and we can see some things about energy flow that
affect life. With infrared film, warm objects ap- pear red and
39. cool objects blue. Figure 6.13 shows birch trees in a New
Hampshire forest, both as we see them, us- ing standard film,
and with infrared film. The infrared film shows tree leaves
bright red, indicating that they have been warmed by the sun
and are absorbing and reflecting energy, whereas the white
birch bark remains cooler. The ability of tree leaves to absorb
energy is essential; it is this source of energy that ultimately
supports all life in a forest. Energy flows through life, and
energy flow is a key concept.
The Laws of Thermodynamics and the Ultimate Limit on the
Abundance of Life
When we discuss ecosystems, we are talking about some of the
fundamental properties of life and of the ecological systems that
keep life going. A question that frequently arises both in basic
science and when we want to produce a lot of some kind of
life—a crop, biofuels, pets—is: What ultimately limits the
amount of organic matter in living things that can be produced
anywhere, at any time, forever on the Earth or anywhere in the
universe?
We ask this question when we are trying to improve the
production of some form of life. We want to know: How closely
do ecosystems, species, populations, and individuals approach
this limit? Are any of these near to being as productive as
possible?
The answers to these questions, which are at the same time
40. practical, scientifically fundamental, and philosophical, lie in
the laws of thermodynamics. The first law of thermodynamics,
known as the law of con- servation of energy states that in any
physical or chemi- cal change, energy is neither created nor
destroyed but merely changed from one form to another. (See
Work- ing It Out 6.1.) This seems to lead us to a confusing,
contradictory answer—it seems to say that we don’t need to take
in any energy at all! If the total amount of energy is always
conserved—if it remains constant— then why can’t we just
recycle energy inside our bodies? The famous 20th-century
physicist Erwin Schrödinger asked this question in a wonderful
book entitled What Is Life? He wrote:
In some very advanced country (I don’t remem- ber whether it
was Germany or the U.S.A. or both) you could find menu cards
in restaurants indicating, in addition to the price, the energy
content of every dish. Needless to say, taken lit- erally, this is .
. . absurd. For an adult organism the energy content is as
stationary as the material content. Since, surely, any calorie is
worth as much as any other calorie, one cannot see how a mere
ex- change could help.
Schrödinger was saying that, according to the first law of
thermodynamics, we should be able to recycle energy in our
bodies and never have to eat anything. Similarly, we can ask:
Why can’t energy be recycled in ecosystems and in the
biosphere?
41. Let us imagine how that might work, say, with frogs and
mosquitoes. Frogs eat insects, including mosquitoes.
Mosquitoes suck blood from vertebrates, including frogs.
Consider an imaginary closed ecosystem consisting of wa- ter,
air, a rock for frogs to sit on, frogs, and mosquitoes. In this
system, the frogs get their energy from eating the mosquitoes,
and the mosquitoes get their energy from bit- ing the frogs
(Figure 6.15). Such a closed system would be a biological
perpetual-motion machine. It could continue indefinitely
without an input of any new material or energy. This sounds
nice, but unfortunately it is impossible. Why? The general
answer is found in the second law of thermody- namics, which
addresses how energy changes in form.
To understand why we cannot recycle energy, imagine a closed
system (a system that receives no input after the initial input)
containing a pile of coal, a tank of water, air, a steam engine,
and an engineer (Figure 6.16). Suppose the engine runs a lathe
that makes furniture. The engineer lights a fire to boil the
water, creating steam to run the en- gine. As the engine runs,
the heat from the fire gradually warms the entire system.
When all the coal is completely burned, the engineer will not be
able to boil any more water, and the engine will stop. The
average temperature of the system is now higher than the
starting temperature. The energy that was in the coal is
dispersed throughout the entire system, much of it as heat in the
42. air. Why can’t the engineer recover all that en- ergy, recompact
it, put it under the boiler, and run the en- gine? The answer is in
the second law of thermodynamics. Physicists have discovered
that no use of energy in the real (not theoretical) world can ever
be 100% efficient. Whenever useful work is done, some energy
is inevitably converted to heat. Collecting all the energy
dispersed in this closed system would require more energy than
could be recovered.
Our imaginary system begins in a highly organized state, with
energy compacted in the coal. It ends in a less organized state,
with the energy dispersed throughout the system as heat. The
energy has been degraded, and the system is said to have
undergone a decrease in order. The measure of the decrease in
order (the disorganization of energy) is called entropy. The
engineer did produce some furniture, converting a pile of
lumber into nicely ordered tables and chairs. The system had a
local increase of order (the furniture) at the cost of a general
increase in disorder (the state of the entire system). All energy
of all systems tends to flow toward states of increasing entropy.
The second law of thermodynamics gives us a new un-
derstanding of a basic quality of life. It is the ability to create
order on a local scale that distinguishes life from its nonliving
environment. This ability requires obtaining energy in a usable
form, and that is why we eat. This principle is true for every
ecological level: individual, population, commu- nity,
43. ecosystem, and biosphere. Energy must continually be added to
an ecological system in a usable form. Energy is inevitably
degraded into heat, and this heat must be re- leased from the
system. If it is not released, the tempera- ture of the system will
increase indefinitely. The net flow of energy through an
ecosystem, then, is a one-way flow.
Based on what we have said about the energy flow through an
ecosystem, we can see that an ecosystem must lie between a
source of usable energy and a sink for de- graded (heat) energy.
The ecosystem is said to be an inter- mediate system between
the energy source and the energy sink. The energy source,
ecosystem, and energy sink to- gether form a thermodynamic
system. The ecosystem can undergo an increase in order, called
a local increase, as long as the entire system undergoes a
decrease in order, called a global decrease. (Note that order has
a specific meaning in thermodynamics: Randomness is disorder;
an ordered system is as far from random as possible.) To put all
this simply, creating local order involves the production of
organic matter. Producing organic matter requires energy;
organic matter stores energy.
With these fundamentals in mind, we can turn to prac- tical and
empirical scientific problems, but this requires that we agree
how to measure biological production. To complicate matters,
there are several measurement units involved, depending on
what people are interested in.
44. 6.5 Biological production and Biomass
The total amount of organic matter in any ecosystem is called
its biomass. Biomass is increased through biologi- cal
production (growth). Change in biomass over a given period is
called production. Biological production is the capture of usable
energy from the environment to produce organic matter (or
organic compounds). This cap- ture is often referred to as
energy “fixation,” and it is often said that the organism has
“fixed” energy. There are two kinds of production, gross and
net. Gross production is the increase in stored energy before any
is used; net pro- duction is the amount of newly acquired energy
stored after some energy has been used. When we use energy,
we “burn” a fuel through respiration. The difference between
gross and net production is like the difference between a
person’s gross and net income. Your gross income is the amount
you are paid. Your net income is what you have left after taxes
and other fixed costs. Respiration is like the expenses that are
required in order for you to do your work. (See Working It Out
6.2.)
Measuring Biomass and Production
Three measures are used for biomass and biological pro-
duction: The quantity of organic material (biomass), en- ergy
stored, and carbon stored. We can think of these measures as the
currencies of production. Biomass is usu- ally measured as the
amount per unit surface area—for example, as grams per square
45. meter (g/m2) or metric tons per hectare (MT/ha). Production, a
rate, is the change per unit area in a unit of time—for example,
grams per square meter per year. (Common units of measure of
production are given in the Appendix.)
The production carried out by autotrophs is called primary
production; that of heterotrophs is called secondary production.
As we have said, most autotrophs make sugar from sunlight,
carbon dioxide, and water in a process called photosynthesis,
which releases free oxygen (see Working It Out 6.1 and 6.2).
Some autotrophic bac- teria can derive energy from inorganic
sulfur compounds; these bacteria are referred to as
chemoautotrophs. Such bacteria live in deep-ocean vents, where
they provide the basis for a strange ecological community.
Chemoauto- trophs are also found in muds of marshes, where
there is no free oxygen.
Once an organism has obtained new organic mat- ter, it can use
the energy in that organic matter to do things: to move, to make
new compounds, to grow, to reproduce, or to store it for future
uses. The use of energy from organic matter by most
heterotrophic and autotro- phic organisms is accomplished
through respiration. In respiration, an organic compound
combines with oxy- gen to release energy and to produce carbon
dioxide and water (see Working It Out 6.2). The process is
similar to the burning of organic compounds but takes place
within cells at much lower temperatures through enzyme-medi-
46. ated reactions. Respiration is the use of biomass to release
energy that can be used to do work. Respiration returns to the
environment the carbon dioxide that had been re- moved by
photosynthesis.
6.6 Energy Efficiency and transfer Efficiency
How efficiently do living things use energy? This is an im-
portant question for the management and conservation of all
biological resources. We would like biological resourc- es to
use energy efficiently—to produce a lot of biomass from a given
amount of energy. This is also important for attempts to
sequester carbon by growing trees and other perennial
vegetation to remove carbon dioxide from the atmosphere and
store it in living and dead organic matter (see Chapter 20).
As you learned from the second law of thermody- namics, no
system can be 100% efficient. As energy flows through a food
web, it is degraded, and less and less is usable. Generally, the
more energy an organism gets, the more it has for its own use.
However, organisms differ in how efficiently they use the
energy they obtain. A more ef- ficient organism has an
advantage over a less efficient one.
Efficiency can be defined for both artificial and natu- ral
systems: machines, individual organisms, populations, trophic
levels, ecosystems, and the biosphere. Energy efficiency is
defined as the ratio of output to input, and it is usually further
defined as the amount of useful work obtained from some
47. amount of available energy. Efficiency has different meanings
to different users. From the point of view of a farmer, an
efficient corn crop is one that con- verts a great deal of solar
energy to sugar and uses little of that sugar to produce stems,
roots, and leaves. In other words, the most efficient crop is the
one that has the most harvestable energy left at the end of the
season. A truck driver views an efficient truck as just the
opposite: For him, an efficient truck uses as much energy as
possible from its fuel and stores as little energy as possible (in
its exhaust). When we view organisms as food, we define
efficiency as the farmer does, in terms of energy storage (net
production from available energy). When we are en- ergy users,
we define efficiency as the truck driver does, in terms of how
much useful work we accomplish with the available energy.
Consider the use of energy by a wolf and by one of its principal
prey, moose. The wolf needs energy to travel long distances and
hunt, and therefore it will do best if it uses as much of the
energy in its food as it can. For itself, a highly energy-efficient
wolf stores almost nothing. But from its point of view, the best
moose would be one that used little of the energy it took in,
storing most of it as muscle and fat, which the wolf can eat.
Thus what is efficient depends on your perspective.
A common ecological measure of energy efficiency is called
food-chain efficiency, or trophic-level efficiency, which is the
ratio of production of one trophic level to the pro- duction of
48. the next-lower trophic level. This efficiency is never very high.
Green plants convert only 1–3% of the energy they receive from
the sun during the year to new plant tissue. The efficiency with
which herbivores convert the potentially available plant energy
into herbivorous energy is usually less than 1%, as is the
efficiency with which carnivores convert herbivores into
carnivorous en- ergy. In natural ecosystems, the organisms in
one trophic level tend to take in much less energy than the
potential maximum available to them, and they use more energy
than they store for the next trophic level. At Isle Royale
National Park, an island in Lake Superior, wolves feed on
moose in a natural wilderness. In one study, a pack of 18
wolves killed an average of one moose approximately every 2.5
days,9 which gives wolves a trophic-level efficien- cy of about
0.01%. (In 2012, the wolf population had dropped to nine
individuals on the island, for reasons not yet understood.10)
The rule of thumb for ecological trophic energy ef- ficiency is
that more than 90% (usually much more) of all energy
transferred between trophic levels is lost as heat. Less than 10%
(approximately 1% in natural ecosystems) is fixed as new
tissue. In highly managed ecosystems, such as ranches, the
efficiency may be greater. But even in such systems, it takes an
average of 3.2 kg (7 lb) of vegetable matter to produce 0.45 kg
(1 lb) of edible meat. Cattle are among the least efficient
producers, requiring around 7.2 kg (16 lb) of vegetable matter
49. to produce 0.45 kg (1 lb) of edible meat. Chickens are much
more efficient, using approximately 1.4 kg (3 lb) of vegetable
matter to produce 0.45 kg (1 lb) of eggs or meat. Much attention
has been paid to the idea that humans should eat at a low- er
trophic level in order to use resources more efficiently. (See
Critical Thinking Issue: Should People Eat Lower on the Food
Chain?)
6.7 Ecological Stability and Succession
Ecosystems are dynamic: They change over time both from
external (environmental) forces and from their inter- nal
processes. It is worth repeating the point we made in Chapter 4
about dynamic systems: The classic interpreta- tion of
populations, species, ecosystems, and Earth’s entire biosphere
has been to assume that each is a stable, static system. But the
more we study these ecological systems, the clearer it becomes
that these are dynamic systems, always changing and always
requiring change. Curiously, they persist while undergoing
change.11 We say “curi- ously” because in our modern
technological society we are surrounded by mechanical and
electronic systems that stay the same in most characteristics and
are designed to do so. We don’t expect our car or television or
cell phone to shrink or get larger and then smaller again; we
don’t expect that one component will get bigger or smaller over
time. If anything like this were to happen, those systems would
break.
50. Ecosystems, however, not only change but also then recover and
overcome these changes, and life continues on. It takes some
adjustment in our thinking to accept and understand such
systems.
When disturbed, ecosystems can recover through ecological
succession if the damage is not too great. We can classify
ecological succession as either primary or secondary. Primary
succession is the establishment and development of an
ecosystem where one did not exist previously. Coral reefs that
form on lava emitted from a volcano and cooled in shallow
ocean waters are examples of primary succession. So are forests
that develop on new lava flows, like those released by the
volcano on the big island of Hawaii (Figure 6.17a), and forests
that develop at the edges of retreating glaciers (Figure 6.17b).
Secondary succession is reestablishment of an eco- system after
disturbances. In secondary succession, there are remnants of a
previous biological community, includ- ing such things as
organic matter and seeds. A coral reef that has been killed by
poor fishing practices, pollution, climate change, or predation,
and then recovers, is an ex- ample of secondary succession.
Forests that develop on abandoned pastures or after hurricanes,
floods, or fires are also examples of secondary succession.
Succession is one of the most important ecological processes,
and the patterns of succession have many man- agement
implications (discussed in detail in Chapter 12). We see
51. examples of succession all around us. When a house lot is
abandoned in a city, weeds begin to grow. Af- ter a few years,
shrubs and trees can be found; secondary succession is taking
place. A farmer weeding a crop and a homeowner weeding a
lawn are both fighting against the natural processes of
secondary succession.
Patterns in Succession
Succession follows certain general patterns. When ecologists
first began to study succession, they focused on three cases
involving forests: (1) on dry sand dunes along the shores of the
Great Lakes in North America; (2) in a northern fresh- water
bog; and (3) in an abandoned farm field. These were
particularly interesting because each demonstrated a repeat-
able pattern of recovery and each tended to produce a late stage
that was similar to the late stages of the others.
Dune Succession
Sand dunes are continually being formed along sandy shores
and then breached and destroyed by storms. In any of the Great
Lakes states, soon after a dune is formed on the shores of one of
the Great Lakes, dune grass invades. This grass has special
adaptations to the unstable dune. Just under the surface, it puts
out runners with sharp ends (if you step on one, it will hurt).
The dune grass rap- idly forms a complex network of
underground runners, crisscrossing almost like a coarsely woven
mat. Above the ground, the green stems carry out
52. photosynthesis, and the grasses grow. Once the dune grass is
established, its run- ners stabilize the sand, and seeds of other
plants have a better chance of germinating. The seeds
germinate, the new plants grow, and an ecological community
of many species begins to develop. The plants of this early
stage tend to be small, grow well in bright light, and withstand
the harsh environment—high temperatures in summer, low
temperatures in winter, and intense storms.
Slowly, larger plants, such as eastern red cedar and east- ern
white pine, are able to grow on the dunes. Eventually, a forest
develops, which may include species such as beech and maple.
A forest of this type can persist for many years, but at some
point a severe storm breaches even these heavily vegetated
dunes, and the process begins again (Figure 6.18).
Bog Succession
A bog is an open body of water with surface inlets— usually
small streams—but no surface outlet. As a result, the waters of
a bog are quiet, flowing slowly if at all. Many bogs that exist
today originated as lakes that filled depres- sions in the land,
which in turn were created by glaciers during the Pleistocene
ice age. Succession in a northern bog, such as the Livingston
Bog in Michigan (Figure 6.19), begins when a sedge (a grasslike
herb) puts out floating runners (Figure 6.20a, b). These runners
form a complex, matlike network similar to that formed by dune
grass. The stems of the sedge grow on the runners andcarry out
53. photosynthesis. Wind blows particles onto the mat, and soil, of
a kind, develops. Seeds of other plants, instead of falling into
the water, land on the mat and can germinate. The floating mat
becomes thicker as small shrubs and trees, adapted to wet
environments, grow. In the North, these include species of the
blueberry family.
The bog also fills in from the bottom as streams carry fine
particles of clay into it (Figure 6.20b, c). At the shore, the
floating mat and the bottom sediments meet, forming a solid
surface. But farther out, a “quaking bog” occurs. You can walk
on this mat; and if you jump up and down, all the plants around
you bounce and shake because the mat is really floating.
Eventually, as the bog fills in from the top and the bottom, trees
grow that can withstand wet- ter conditions—such as northern
cedar, black spruce, and balsam fir. The formerly open-water
bog becomes a wet- land forest. If the bog is farther south, it
may eventually be dominated by beech and maple, the same
species that dominate the late stages of the dunes.
Old-Field Succession
In the northeastern United States, a great deal of land was
cleared and farmed in the 18th and 19th centuries. Today, much
of this land has been abandoned for farming and allowed to
grow back to forest (Figure 6.21). The first plants to enter the
abandoned farmlands are small plants adapted to the harsh and
highly variable conditions of a clearing—a wide range of
54. temperatures and precipitation. As these plants become
established, other, larger plants en- ter. Eventually, large trees
grow, such as sugar maple, beech, yellow birch, and white pine,
forming a dense forest.
Since these three different habitats—one dry (the dunes), one
wet (the bog), and one in between (the old field)—tend to
develop into similar forests, early ecolo- gists believed that this
late stage was in fact a steady-state condition. They referred to
it as the “climatic climax,” meaning that it was the final,
ultimate, and permanent stage to which all land habitats would
proceed if undis- turbed by people. Thus, the examples of
succession were among the major arguments in the early 20th
century that nature did in fact achieve a constant condition, a
steady state, and there actually was a balance of nature. We
know today that this is not true, a point we will return to later.
Coral Reef Succession
Coral reefs (Figure 6.22) are formed in shallow warm waters by
corals—small marine animals that live in colo- nies and are
members of the phylum Coelenterata, which also includes sea
anemones and jellyfishes. Corals have a whorl of tentacles
surrounding the mouth, and feed by catching prey, including
planktonic algae, as it passes by. The corals settle on a solid
surface and produce a hard polyp of calcium carbonate (in other
words, limestone). As old individuals die, this hard material
becomes the surface on which new individuals establish
55. themselves. Coralline algae, a kind of red algae that also uses
calcium carbonate, is also important in the formation of the
reefs. In addition, other limestone-shell-forming organisms such
as certain snails and sea urchins live and die on the reef and are
glued together by coralline algae. Eventu- ally a large and
complex structure results involving many other species,
including autotrophs and heterotrophs, creating one of the most
species-diverse of all kinds of ecosystems. Highly valued for
this diversity, for produc- tion of many edible fish, for the coral
itself (used in vari- ous handicrafts and arts), and for recreation,
coral reefs attract lots of attention.
Succession, in Sum
Even though the environments are very different, these four
examples of ecological succession—dune, bog, old field, and
coral reef—have common elements found in most ecosystems:
1. An initial kind of autotroph (green plants in three of the
examples discussed here; algae and photosynthetic bacteria in
marine systems; algae and photosynthetic bacteria, along with
some green plants in some freshwater and near-shore marine
systems). These are typically small in stature and specially
adapted to the unstable conditions of their environment.
2. A second stage with autotrophs still of small stature, rapidly
growing, with seeds or other kinds of reproductive structures
that spread rapidly.
3. A third stage in which larger autotrophs—like trees in forest
56. succession—enter and begin to dominate the site.
4. A fourth stage in which a mature ecosystem develops.
Although we list four stages, it is common practice to combine
the first two and speak of early-, middle-, and late-successional
stages. The stages of succession are de- scribed here in terms of
autotrophs, but similarly adapt- ed animals and other life forms
are associated with each stage. We discuss other general
properties of succession later in this chapter.
Species characteristic of the early stages of succes- sion are
called pioneers, or early-successional species. They have
evolved and are adapted to the environmen- tal conditions in
early stages of succession. In terrestrial ecosystems, vegetation
that dominates late stages of suc- cession, called late-
successional species, tends to be slower growing and longer
lived, and can persist under intense competition with other
species. For example, in terrestrial ecosystems, late-
successional vegetation tends to grow well in shade and have
seeds that, though not as widely dispersing, can persist a rather
long time. Typical middle-successional species have
characteristics in between the other two types.
6.8 Chemical Cycling and Succession
In Chapter 4, we introduced the biogeochemical cycle. One of
the important effects of succession is a change in the storage of
chemical elements necessary for life. On land, the storage of
chemical elements essential for plant growth and function
57. (including nitrogen, phospho- rus, potassium, and calcium)
generally increases during the progression from the earliest
stages of succession to middle succession (Figure 6.23). There
are three reasons for this:
Increased storage. Organic matter, living or dead, stores
chemical elements. As long as there is an increase in organic
matter within the ecosystem, there will be an increase in the
storage of chemical elements.
Increased rate of uptake. For example, in terrestrial ecosystems,
many plants have root nodules containing bacteria that can
assimilate atmospheric nitrogen, which is then used by the plant
in a process known as nitrogen fixation.
Decreased rate of loss. The presence of live and dead organic
matter helps retard erosion. Both organic and in- organic soil
can be lost to erosion by wind and water. Veg- etation and, in
certain marine and freshwater ecosystems, large forms of algae
tend to prevent such losses and there- fore increase total stored
material.
Ideally, chemical elements could be cycled indefinite- ly in
ecosystems, but in the real world there is always some loss as
materials are moved out of the system by wind and water. As a
result, ecosystems that have persisted con- tinuously for the
longest time are less fertile than those in earlier stages. For
example, where glaciers melted back thousands of years ago in
New Zealand, forests developed, but the oldest areas have lost
58. much of their fertility and have become shrublands with less
diversity and biomass. The same thing happened to ancient sand
dune vegetation in Australia.11
6.9 how Species Change Succession
Early-successional species can affect what happens later in
succession in three ways: through (1) facilitation, (2)
interference, or (3) life history differences (Figure 6.24).
Facilitation
In facilitation, an earlier-successional species changes the local
environment in ways that make it suitable for another species
that is characteristic of a later successional stage. Dune and bog
succession illustrate facilitation. The first plant species—dune
grass and floating sedge—prepare the way for other species to
grow. Facilitation is common in tropical rain forests, where
early-successional species speed the reappearance of the
microclimatic conditions that occur in a mature forest. Because
of the rapid growth of early-successional plants, after only 14
years the tempera- ture, relative humidity, and light intensity at
the soil surface in tropical forests can approximate those of a
mature rain forest. Once these conditions are established,
species adapt- ed to deep forest shade can germinate and persist.
Facilitation also occurs in coral reefs, mangrove swamps along
ocean shores, kelp beds along cold ocean shores such as the
Pacific coast of the United States and Canada’s Pacific
Northwest, and in shallow marine ben- thic areas where the
59. water is relatively calm and large algae can become established.
Knowing the role of facilitation can be useful in the restoration
of damaged areas. Plants that facilitate the presence of others
should be planted first. On sandy areas, for example, dune
grasses can help hold the soil before we attempt to plant shrubs
or trees.
Interference
In contrast to facilitation, interference refers to situations where
an earlier-successional species changes the local envi- ronment
so that it is unsuitable to another species character- istic of a
later-successional stage. Interference is common, for example,
in American tall-grass prairies, where prairie grasses like little
bluestem form a mat of living and dead stems so dense that
seeds of other plants cannot reach the ground and therefore do
not germinate. Interference does not last forever, however.
Eventually, some breaks occur in the grass mat—perhaps from
surface-water erosion, the death of a patch of grass from
disease, or removal by fire. Breaks in the grass mat allow seeds
of trees to germinate. For example, in the tall-grass prairie,
seeds of red cedar can then reach the ground. Once started, red
cedar soon grows taller than the grasses, shading them so much
that they can- not grow. More ground is open, and the grasses
are eventu- ally replaced.
The same pattern occurs in some Asian tropical rain forests. The
grass, Imperata, forms stands so dense that seeds of later-
60. successional species cannot reach the ground. Imperata either
replaces itself or is replaced by bamboo, which then replaces
itself. Once established, Imperata and bamboo appear able to
persist for a long time. Once again, when and if breaks occur in
the cover of these grasses, other species can germinate and
grow, and a forest eventually develops.
Life History Differences
In this case, changes in the time it takes different species to
establish themselves give the appearance of a succes- sion
caused by species interactions, but it is not. In cases where no
species interact through succession, the result is termed chronic
patchiness. Chronic patchiness is char- acteristic of highly
disturbed environments and highly stressful ones in terms of
temperature, precipitation, or chemical availability, such as
deserts. For example, in the warm deserts of California,
Arizona, and Mexico, the ma- jor shrub species grow in patches,
often consisting of ma- ture individuals with few seedlings.
These patches tend to persist for long periods until there is a
disturbance. Simi- larly, in highly polluted environments, a
sequence of spe- cies replacement may not occur. Chronic
patchiness also describes planktonic ecological communities
and their ecosystems, which occur in the constantly moving
waters of the upper ocean and the upper waters of ponds, lakes,
rivers, and streams.
SUMMARY
61. • An ecosystem is the simplest entity that can sustain life. At its
most basic, an ecosystem consists of several species and a fluid
medium (air, water, or both). The ecosystem must sustain two
processes—the cycling of chemical elements and the flow of
energy.
• The living part of an ecosystem is the ecological com- munity,
a set of species connected by food webs and trophic levels. A
food web or food chain describes who feeds on whom. A trophic
level consists of all the organ- isms that are the same number of
feeding steps from the initial source of energy.
• Community-level effects result from indirect interac- tions
among species, such as those that occur when sea otters
influence the abundance of sea urchins.
• Ecosystems are real and important, but it is often diffi- cult to
define the limits of a system or to pinpoint all the interactions
that take place. Ecosystem management is considered key to the
successful conservation of life on Earth.
Energy flows one way through an ecosystem; the sec- ond law
of thermodynamics places a limit on the abun- dance of
productivity of life and requires the one-way flow.
Chemical elements cycle, and in theory could cycle forever, but
in the real world there is always some loss.
Ecosystems recover from changes through ecological
succession, which has repeatable patterns.
Ecosystems are nonsteady-state systems, undergoing changes all
62. the time and requiring change.
FURThER READing
Modern Studies Botkin, D.B., No Man’s Garden: Thoreau and a
New Vision for
Civilization and Nature (Washington, DC: Island Press, 2001).
Chapin, F. Stuart, III, Harold A. Mooney, Melissa C. Chapin,
and Pamela Matson, Principles of Terrestrial Ecosystem
Ecology (New York: Springer, 2004, paperback).
Kaiser, Michel J., Martin J. Attrill, Simon Jennings and David
N. Thomas, Marine Ecology: Processes, Systems, and Impacts
(New York: Oxford University Press, 2011).
Some Classic Studies and Books
Blum, H.F., Time’s Arrow and Evolution (New York: Harper &
Row, 1962). A very readable book; the author discusses how
life is connected to the laws of thermodynamics and why this
matters.
Bormann, F.H., and G.E. Likens, Pattern and Process in a For-
ested Ecosystem, 2nd ed. (New York: Springer-Verlag, 1994). A
synthetic view of the northern hardwood ecosystem, including
its structure, function, development, and relationship to
disturbance.
Gates, D.M., Biophysical Ecology (New York: Springer-Verlag,
1980). A discussion about how energy in the environment af-
fects life.
Morowitz, H.J., Energy Flow in Biology (Woodbridge, CT:
63. Oxbow, 1979). The most thorough and complete discussion
available about the connection between energy and life, at all
levels, from cells to ecosystems to the biosphere.
Odum, Eugene, and G.W. Barrett, Fundamentals of Ecology
(Duxbury, MA: Brooks/Cole, 2004). Odum’s original textbook
was a classic, especially in providing one of the first serious in-
troductions to ecosystem ecology. This is the latest update of
the late author’s work, done with his protégé.
Schrödinger, E. (ed. Roger Penrose), What Is Life?: With Mind
and Matter and Autobiographical Sketches (Canto) (Cambridge:
Cambridge University Press, 1992). The origi- nal statement
about how the use of energy differentiates life from other
phenomena in the universe. Easy to read and a classic.
Botkin, D. B., & Keller, E. A. (2014). Environmental science:
Earth as a living planet (9th ed.). Hoboken, NJ: John Wiley &
Sons, Inc
64. CHAPTER 4
· Botkin, D. B., & Keller, E. A. (2014). Environmental science:
Earth as a living planet (9th ed.). Hoboken, NJ: John Wiley &
Sons, Inc
· Chapter 4: The Big Picture: Systems of Change
4.1 Basic Systems Concepts
A system is a set of components, or parts, that func- tion
together as a whole. A single organism, such as your body, is a
system, as are a sewage-treatment plant, a city, and a river. On
a much different scale, the entire Earth is a system. In a broader
sense, a system is any part of the universe you can isolate in
thought (in your brain or on your computer) or, indeed,
physically, for the purpose of study. Key systems concepts that
we will explain are:
• how a system is connected to the rest of the environment;
• how matter and energy flow between parts of a system;
• whether a system is static or dynamic—whether it changes
over time;
• average residence time—how long something stays within a
system or part of a system;
• feedback—how the output from a system can affect its inputs;
65. and
• linear and nonlinear flows.
In its relation to the rest of the environment, a sys- tem can be
open or closed. In an open system, some en- ergy or material
(solid, liquid, or gas) moves into or out of the system. The
ocean is an open system with regard to water because water
moves into the ocean from the atmosphere and out of the ocean
into the atmosphere. In a closed system, no such transfers take
place. For our purposes, a materially closed system is one in
which no matter moves in and out of the system, although
energy and information can move across the system’s boundar-
ies. Earth is a materially closed system (for all practical
purposes).
Systems respond to inputs and have outputs. For example, think
of your body as a complex system and imagine you are hiking in
Yellowstone National Park and see a grizzly bear. The sight of
the bear is an input. Your body reacts to that input: The
adrenaline level in your blood goes up, your heart rate
increases, and the hair on your head and arms may rise. Your
response—perhaps to move slowly away from the bear—is an
output.
Static and Dynamic Systems
A static system has a fixed condition and tends to remain in that
exact condition. A dynamic system changes, often continually,
over time. A birthday balloon attached to a pole is a static
66. system in terms of space—it stays in one place. A hot-air
balloon is a simple dynamic system in terms of space—it moves
in response to the winds, air density, and controls exerted by a
pilot (Figure 4.4a and 4.4b).
An important kind of static system is one with classical
stability. Such a system has a constant condition, and if it is
disturbed from that condition, it returns to it once the disturbing
factor is removed. The pendulum of an old-fashioned
grandfather clock is an example of classical stability. If you
push it, the pendulum moves back and forth for a while, but
then friction gradually dissipates the energy you just gave it and
the pendulum comes to rest exactly where it began. This rest
point is known as the equilibrium (Figure 4.4c).
We will see that the classic interpretation of popula- tions,
species, ecosystems, and Earth’s entire biosphere has been to
assume that each is a stable, static system. But the more these
ecological systems are studied scientifically, the clearer it
becomes that these are dynamic systems, always changing and
always requiring change. An important prac- tical question that
keeps arising in many environmental controversies is whether
we want to, and should, force ecological systems to be static if
and when they are natu- rally dynamic. You will find this
question arising in many of the chapters in this book.
Open Systems
With few exceptions, all real systems that we deal with in the
67. environment are open to the flow of matter, en- ergy, and
information. (For all practical purposes, as we noted earlier,
Earth as a planet is a materially closed system.) An important
distinction for open systems is whether they are steady-state or
nonsteady-state. In a steady-state system, the inputs (of
anything of interest) are equal to the outputs, so the amount
stored within the system is constant. An idealized example of a
steady- state system is a dam and lake into which water enters
from a river and out of which water flows. If the water input
equals the water output and evaporation is not considered, the
water level in the lake does not change, and so, in regard to
water, the lake is in a steady state. (Additional characteristics of
systems are discussed in A Closer Look 4.1.)
Two of the river’s great floods were in 1927 and 1993 (Figure
4.6). After the 1927 flood, the federal government
commissioned the Army Corps of Engineers to build six major
dams on the river (Figure 4.7). (The attempt to control the
river’s flow also included many other alterations of the river,
such as straightening the channel and building levees.) Of the
six dams, the three largest were built upstream, and each of
their reservoirs was supposed to hold the equivalent of an entire
year’s average flow. The three smaller, downstream dams were
meant to serve as safety valves to control the flow more
precisely.
The underlying idea was to view the Missouri as a large
68. plumbing system that needed management. When rain- fall was
sparse in the huge watershed of the river, the three upstream
dams were supposed to be able to augment the flow for up to
three years, ensuring a constant and adequate supply of water
for irrigation and personal use. In flood years, the six dams
were supposed to be able to store the danger- ous flow so that
the water could be released slowly, the floods controlled, and
the flow once again constant. In addition, levees—narrow ridges
of higher ground—were built along the river and into it to
protect the settled land along the river from floodwaters not
otherwise contained. But these ideal- istic plans did not stop the
Missouri from flooding in 1993 (Figures 4.6 and 4.8).
Taking the large view, standing way back from the river, led to
a perception of the Missouri River as one huge lake (Figure 4.9)
into which water flowed, then drained down- stream and out at
its mouth at St. Louis, Missouri, into the Mississippi, which
carried the waters to New Orleans, Louisiana, and out into the
Gulf of Mexico. The Army Corps of Engineers’ hope was that
the Missouri River could be managed the way we manage our
bathwater—keeping it at a constant level by always matching
the outflow down the drain with inflow from the spigot. This is
a perception of the river as a system held in steady state, a term
we defined earlier.
An environmental water engineer could use this kind of systems
diagram (Figure 4.10) to plan the size of the various dams to be
69. built on the Missouri River, taking into account the desired total
storage among the dams and the role of each dam in managing
the river’s flow. In Figure 4.10, the amount stored in a dam’s
reservoir is listed as Xn, where X is the amount of water stored
and n is the number of the compart- ment. (In this case the dams
are numbered in order from up- stream to downstream.) Water
flows from the environment— tributaries, watersheds, and
direct rainfall—into each of the reservoirs, and each is
connected to the adjacent reservoirs by the river. Finally, all of
the Missouri’s water flows into the Mississippi, which carries it
to the Gulf of Mexico.
Looking at Figure 4.10, can you think of problems as- sociated
with the input–output of the river and managing water
reservoirs in such a large system? Can you name some
consequences likely to arise when attempting to keep a river in
a steady state?
The average residence time (ART) is the ratio of the size of a
reservoir of some material—say, the amount of water in a
reservoir—to the rate of its transfer through the res- ervoir. The
equation is
ART 5 S/F
where S is the size of the reservoir and F is the rate of transfer.
For example, we can calculate the average residence time for
water in the Gavins Point Dam (see Figure 4.10), the farthest
downstream of all the dams on the Missouri River, by realizing
70. that the average flow into and out of the dam is about 25 million
acre-feet (31 km3) a year, and that the dam stores about 492,000
acre-feet (0.6 km3). This suggests that the average residence
time in the dam is only about seven days:
33 ART 5 S/F 5 0.6 kmraey repmk 13ﰀ
S/F 5 0.019 year (about 7 days)
If the total flow were to go through Garrison Dam, the largest of
the dams, the residence time would be 347 days, almost a year.
The ART for a chemical element or compound is im- portant in
evaluating many environmental problems. For example,
knowing the ART of a pollutant in the air, water, or soil gives
us a more quantitative understanding of that pollutant, allows us
to evaluate the extent to which the pollutant acts in time and
space, and helps us to develop strategies to reduce or eliminate
the pollutant.
Figure 4.11 shows a map of Big Lake, a hypotheti- cal reservoir
impounded by a dam. Three rivers feed a combined 10 m3/sec
(2,640 gal/sec) of water into the lake, and the outlet structure
releases an equal 10 m3/sec. In this simplified example, we will
assume that evaporation of water from the lake is negligible. A
water pollutant, MTBE (methyl tertiary—butyl ether), is also
present in the lake. MTBE is added to gasoline to help reduce
emissions of carbon monoxide. MTBE readily dissolves in water
and so travels with it. It is toxic; in small concentrations of 20–
40 mg/l (milliononths of grams per liter) in water, it smells like
71. turpentine and is nauseating to some people. Concern over
MTBE in California led to a decision to stop add- ing it to
gasoline. The sources of MTBE in “Big Lake” are urban runoff
from Bear City gasoline stations, gas- oline spills on land or in
the lake, and gasoline engines used by boats on the lake.
68 Chapter 4 The Big Picture: Systems of Change ART5 S 5
ART5 1,000,000,000 m3
10 m3cesﰀ
ART 5 100,000,000 sec or 108 sec Convert 108 sec to years:
seconds 560 sec3 60 minute 3 24 hours 3 365 days year1
minute1 hour1 day1 year
Canceling units and multiplying, there are 31,536,000 sec ,raeyﰀ
which is
3.1536 3 107 secsi ekaL giB rof TRA eht nehT raeyﰀ
100,000,000sec or108sec 31,536,000 sec 701 3 6351.3ryﰀ
secryﰀ
Therefore the ART for water in Big Lake is 3.17 years.
ART of MTBE in Big Lake
The concentration of MTBE in water near the dam is measured
as 10 mg fo ezis) ekal eht ni EBTM fo tnuoma latot eht nehT .lﰀ
reservoir or pool of MTBE) is the product of volume of water in
the lake and concentration of MTBE:
109 m3 3 103l 3 10mg51013mgor107 g m3 l
which is 104 kg, or 10 metric tons, of MTBE.3 The output of
water from Big Lake is 10 m lﰀgm 01 sniatnoc siht dna ,cesﰀ
72. of MTBE; the transfer rate of
waterFwater 109m3
or 10m3dna tuo lecnac 3m stinu ehT cesﰀ
MTBE (g3 3m 3 ces 5cesﰀEBTM si (cesﰀ l 3 mg
5 0.1 g EBTM fo tuptuo dna tupni taht emussa ew esuaceB cesﰀ
are
equal, the input is also 0.1 g 801 5g 7015 S 5 EBTMTRA .cesﰀ
sec, or 3.17 years
10 m3103 l10 mg1026 g
F0.1 gcesﰀ
Thus, as we suspected, the ARTs of the water and MTBE are the
same. This is because MTBE is dissolved in the water. If it
attached to the sediment in the lake, the ART of the MTBE
would be much longer. Chemicals with large reservoirs or small
rates of transfer tend to have long ARTs. In this exercise we
have calculated the ART of water in Big Lake as well as the
input, total amount, and ART of MTBE.
Often we want real systems in the environment to be in a steady
state, and we try to manage many of them so they will be.
Attempts to force natural ecological and environmental systems
into a steady state often fail. In fact, such attempts commonly
make things worse in- stead of better, as we will see in many
chapters in this book.
The Balance of Nature: Is a Steady State Natural?
An idea frequently used and defended in the study of our natural
73. environment is that natural systems, left un- disturbed by
people, tend toward some sort of steady state. The technical
term for this is dynamic equi- librium, but it is more familiarly
referred to as the balance of nature (see Figure 4.12). Certainly,
negative feedback operates in many natural systems and may
tend to hold a system at equilibrium. Nevertheless, we need to
ask how often the equilibrium model really applies.4
If we examine natural ecological systems or eco- systems
(simply defined here as communities of or- ganisms and their
nonliving environment in which nutrients and other chemicals
cycle and energy flows) in detail and over a variety of time
frames, it is evident that a steady state is seldom attained or
maintained for very long. Rather, systems are characterized not
only by human-induced disturbances but also by natural
disturbances (sometimes large-scale ones called natural
disasters, such as floods and wildfires). Thus, changes over time
can be expected. In fact, studies of such di- verse systems as
forests, rivers, and coral reefs suggest that disturbances due to
natural events, such as storms, floods, and fires, are necessary
for the maintenance of those systems, as we will see in later
chapters. The envi- ronmental lesson is that systems change
naturally. If we are going to manage systems for the betterment
of the environment, we need to gain a better understanding of
how they change.4, 5
Residence Time
74. By using rates of change or input–output analysis of sys- tems,
we can derive an average residence time—how long, on average,
a unit of something of interest to us will remain in a reservoir.
This is obviously important, as in the case of how much water
can be stored for how long in a reservoir. To compute the
average residence time (assuming input is equal to output), we
divide the total volume of stored water in the reservoir by the
av- erage rate of transfer through the system. For example,
suppose a university has 10,000 students, and each year 2,500
freshmen start and 2,500 seniors graduate. The av- erage
residence time for students is 10,000 divided by 2,500, or four
years.
Average residence time has important implications for
environmental systems. A system such as a small lake with an
inlet and an outlet and a high transfer rate of water has a short
residence time for water. On the one hand, from our point of
view, that makes the lake espe- cially vulnerable to change
because change can happen quickly. On the other hand, any
pollutants soon leave the lake.
In large systems with a slow rate of transfer of water, such as
oceans, water has a long residence time, and such systems are
thus much less vulnerable to quick change. However, once they
are polluted, large systems with slow transfer rates are difficult
to clean up. (See Working It Out 4.1.)
Feedback
75. Feedback occurs when the output of a system (or a com-
partment in a system) affects its input. Changes in the output
“feed back” on the input. There are two kinds of feedback:
negative and positive. A good example of feedback is human
temperature regulation. If you go out in the sun and get hot, the
increase in temperature affects your sensory perceptions (input).
If you stay in the sun, your body responds physiologically: Your
pores open, and you are cooled by evaporating water (you
sweat). The cooling is output, and it is also input to your sen-
sory perceptions. You may respond behaviorally as well:
Because you feel hot (input), you walk into the shade (output)
and your temperature returns to normal. In this example, an
increase in temperature is followed by a re- sponse that leads to
a decrease in temperature. This is an example of negative
feedback, in which an increase in output leads to a further
decrease in output. Negative feedback is self-regulating or
stabilizing. It is the way that steady-state systems can remain in
a constant condition.
Positive feedback occurs when an increase in output leads to a
further increase in output. A fire starting in a forest provides an
example of positive feedback. The wood may be slightly damp
at the beginning and so may not burn readily. Once a fire starts,
wood near the flame dries out and begins to burn, which in turn
dries out a greater quantity of wood and leads to a larger fire.
The larger the fire, the faster more wood becomes dry and the
76. more rap- idly the fire grows. Positive feedback, sometimes
called a “vicious cycle,” is destabilizing.
Environmental damage can be especially serious when people’s
use of the environment leads to positive feedback. For example,
off-road vehicles—including bicycles—may cause positive
feedback to soil erosion (Figure 4.13). The vehicles’ churning
tires are designed to grip the earth, but they also erode the soil
and up- root plants. Without vegetation, the soil erodes faster,
exposing even more soil (positive feedback). As more soil is
exposed, rainwater more easily carves out ruts and gullies (more
positive feedback). Drivers of off-road vehicles then avoid the
ruts and gullies by driving on adjacent sections that are not as
eroded, thus widen- ing paths and further increasing erosion
(more posi- tive feedback). The gullies themselves increase
erosion because they concentrate runoff and have steep side
slopes. Once formed, gullies tend to get longer, wider, and
deeper, causing additional erosion (even more posi- tive
feedback). Eventually, an area of intensive off-road vehicle use
may become a wasteland of eroded paths and gullies. Positive
feedback has made the situation increasingly worse.
Some systems have both positive and negative feed- backs, as
can occur, for example, for the human popu- lation in large
cities (Figure 4.14). Positive feedback on the population size
may occur when people perceive greater opportunities in cities
and move there, hoping for a higher standard of living. As more
77. people move to cit- ies, opportunities may increase, leading to
even more mi- gration to cities. Negative feedback can then
occur when crowding increases air and water pollution, disease,
crime, and discomfort. These negatives encourage some people
to migrate from the cities to rural areas, reducing the city’s
population.Positive
+–
Air pollution, disease, crime, discomfort, traffic
Jobs, health care, social services, higher standard of living
People leave city
People move into the city
Practicing your critical thinking skills, you may ask, “Is
negative feedback generally desirable, and is positive feedback
generally undesirable?” Reflecting on this ques- tion, we can
see that, although negative feedback is self- regulating, it may
in some instances not be desirable. The period over which the
positive or negative feedback occurs is the important factor. For
example, suppose we are inter- ested in restoring wolves to
Yellowstone National Park. We will expect positive feedback in
the wolf population for a time as the number of wolves grows.
(The more wolves, the greater their population growth, through
exponential growth.) Positive feedback, for a time, is desirable
because it produces a change we want.
We can see that whether we view positive or negative feedback
as desirable depends on the system and potential changes.
78. Nevertheless, some of the major environmen- tal problems we
face today result from positive feedback mechanisms. These
include resource use and growth of the human population.
4.2 System Responses: Some Important Kinds of Flows5
Within systems, there are certain kinds of flows that we come
across over and over in environmental science. (Note that flow
is an amount transferred; we also refer to the flux, which is the
rate of transfer per unit time.) Because these are so common, we
will explain a few of them here.
Linear and Nonlinear Flows
An important distinction among environmental and eco- logical
systems is whether they are characterized by linear or nonlinear
processes. Put most simply, in a linear process, if you add the
same amount of anything to a compartment in a system, the
change will always be the same, no mat- ter how much you have
added before and no matter what else has changed about the
system and its environment. If you harvest one apple and weigh
it, then you can estimate how much 10 or 100 or 1,000 or more
of the apples will weigh—adding another apple to a scale does
not change the amount by which the scale shows an increase.
One apple’s effect on a scale is the same, no matter how many
apples were on the scale before. This is a linear effect.
Many important processes are nonlinear, which means that the
effect of adding a specific amount of some- thing changes,
depending on how much has been added before. If you are very
79. thirsty, one glass of water makes you feel good and is good for
your health. Two glasses may also be helpful. But what about
100 glasses? Drinking more and more glasses of water leads
quickly to diminish- ing returns and eventually to water
becoming a poison.
Lag Time
Many responses to environmental inputs (includ- ing human
population change; pollution of land, water, and air; and use of
resources) are nonlinear and may involve delays, which we need
to recog- nize if we are to understand and solve environmen- tal
problems. For example, when you add fertilizer to help a tree
grow, it takes time for it to enter the soil and be used by the
tree.
Exponential Growth Linear Growth
Lag time is the delay between a cause and the appearance of its
effect. (This is also referred to as the time between a stimulus
and the ap- pearance of a response.) If the lag time is long,
especially compared to human lifetimes (or at- tention spans or
our ability to continue measur- ing and monitoring), we can fail
to recognize the change and know what is the cause and what is
the effect. We can also come to believe that a possible cause is
not hav- ing a detrimental effect, when in reality the effect is
only delayed. For example, logging on steep slopes can increase
the likelihood and rate of erosion, but in comparatively dry
environments this may not become apparent until there is heavy