Published on

Published in: Education, Technology
1 Comment
No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide


  1. 1. The Study of Ecology Ecology and the Biosphere
  2. 2. Ecology Ecology is the study of the interactions of organisms with one another and with their physical environment
  3. 3. Ecology comes from the Greek Word “oikos”, which means “house” The Earth is our house. The “house” includes the environment in which organisms live, the interactions of organisms with one another, and the interaction of organisms with the nonliving environment
  4. 4. What is the Biosphere?
  5. 5. Biosphere “The Living Globe” The Biosphere is that part of the Earth in which life exists
  6. 6. Biosphere Includes all land, air, and water Extends from about 8 km above the Earth’s surface to as far as 8 km below the surface of the ocean Living organisms are not distributed uniformly (few in polar regions and many in tropical regions)
  7. 7. Ecosystems Ecosystems are small ecological units Consist of a given area’s physical features and living organisms Nonliving Physical Features are called abiotic factors Water, sunlight, soil type, rocks, temperature, humidity, elevation, and rainfall Living organisms are called biotic factors Bacteria, reptiles, fish, birds, animals, plants, and fungi All of the biotic and abiotic factors in a given area make up an ecosystem
  8. 8. There are many different types of ecosystems in nature… Lake Stream Prairie Forest Wetland
  9. 9. All Ecosystems are Interconnected!!!! Stream
  10. 10. Ecologists who study ecosystems identify the living organisms as part of a….. Population: a collection of individuals of the same species in a given area who can breed with one another
  11. 11. Ecologists who study ecosystems identify the living organisms as part of a….. Community: all the populations of organisms living in a given area (all of the biotic factors)
  12. 12. Ecological Succession What Does it Mean to Succeed???
  13. 13. Ecological Succession The process by which an existing community is gradually replaced by another community Every organism affects environmental conditions around it
  14. 14. Ecological Succession of a Pond Community Begins as a thriving pond community….
  15. 15. Ecological Succession of a Pond Community The pond begins to fill with organic matter like leaves, and silt, a fine soil…..
  16. 16. Ecological Succession of a Pond Community Over a period of time, the pond fills and becomes a marsh…..
  17. 17. Ecological Succession of a Pond Community Eventually the marsh becomes dry land inhabited by a stable community called a climax community
  18. 18. Succession often leads to a fairly stable collection of organisms The Biomes of the World are Large Climax Communities with a Stable Collection of Characteristic Plant and Animal Life!
  19. 19. There are 2 types of succession that occur in nature….. Primary Succession Secondary Succession
  20. 20. Primary Succession •Occurs in places where no living community existed before (on a newly formed volcanic island) •Pioneer species begin to grow Hardy organisms that can tolerate harsh conditions
  21. 21. Secondary Succession • Occurs in areas where natural disasters or human activities have wiped out an existing living community •Pioneer species colonize the area and gradually change conditions so that they are favorable for other species
  22. 22. Ecosystem Dynamics Energy and Nutrients in the Ecosystem
  23. 23. All living things are made up of…. Chemical Elements Chemical Compounds Carbon (C) Water (H2O) Hydrogen (H) Glucose (C6H12O6) Oxygen (O) Proteins (CHON) Nitrogen (N) And use ENERGY!!!!!
  24. 24. Energy Energy…….. The ability to do work Builds cells and tissues Growth Reproduction Responding to environment
  25. 25. Ecosystem Dynamics and Energy Transfer
  26. 26. Energy Energy is passed from organism to organism by feeding relationships in the ecosystem!!! Trophic Levels Each step in the transfer of energy in a community •Producers •Consumers •Decomposers
  27. 27. Producers Organisms that can make their own food Autotrophs (Self-Feeding) • Use photosynthesis to convert sunlight chemical energy • Produce carbohydrates for immediate use or storage for later • Examples include plants, algae, and some bacteria
  28. 28. Consumers Animals, fungi, protists, and most bacteria that cannot make their own food Consumers are Heterotrophs (obtain food by eating other organisms) Types of Consumers: •Primary Consumers •Secondary Consumers •Tertiary Consumers
  29. 29. Classification of Consumers Herbivore •Eat only plants •Primary consumers •Deer, caterpillars, giraffes
  30. 30. Classification of Consumers Carnivore •Eat only other animals •Secondary and tertiary consumers •Lions, wolves, eagles, sharks
  31. 31. Classification of Consumers Omnivore •Eats both plants and animals •Can be primary, secondary, or tertiary consumer •Raccoons, bears
  32. 32. More About Consumers Some consumers are scavengers •Scavengers are animals that eat the flesh of dead organisms •Biological “clean-up crew” •Vultures, hyenas, crows
  33. 33. Decomposers Decomposers are organisms that obtain their energy from dead organisms •Break down complex organic matter (decompose or decay) •Nutrients from break down of tissues are returned to the soil •Nutrients are recycled (carbon, nitrogen, phosphorus) •Bacteria, earthworms
  34. 34. The Flow of Energy Energy flows through an ecosystem. From the sun to producers to consumers to decomposers, energy powers the interactions of ecosystems.
  35. 35. Food Chains •Shows the flow of energy from one organism to another through each trophic level •Energy flow is represented by an arrow •Arrow goes in direction of energy
  36. 36. Food Web •A food web is a representation of all of the interconnected food chains in an ecosystem •Food webs show multiple feeding relationships
  37. 37. The Food Web
  38. 38. Ecological Pyramids Ecologists use ecological pyramids to represent the relationships among trophic levels There are 3 types of ecological pyramids: • Pyramid of Energy • Pyramid of Biomass • Pyramid of Numbers
  39. 39. Pyramid of Energy Shows total amount of incoming energy at each trophic level The 10% rule predicts that only 10% of the energy in one trophic level is available to the next level
  40. 40. Pyramid of Biomass Shows total mass of living tissue at each level
  41. 41. Pyramid of Numbers Shows the total number of organisms at each trophic level
  42. 42. Trophic Levels, Energy Flow, and Ecological Pyramids
  43. 43. Ecological Niche
  44. 44. Factors That Control Population Growth
  45. 45. In nature, population growth is limited to the carrying capacity of the environment Carrying capacity is determined by a variety of limiting factors.
  46. 46. Population Limiting Factors • Factors that control population growth • Maintains population levels between extinction and overpopulation • Two types: • Density-dependent limiting factors • Density-independent limiting factors
  47. 47. Density-Dependent Limiting Factors • Operate only when a population is large • Examples include: • Competition • Predation • Parasitism • Overcrowding • Stress
  48. 48. Competition Competition occurs when two or more species rely on similar limiting resources such as space or food.
  49. 49. Competitive Exclusion Principle When two species are competing for the same resources, one must – migrate to another area – shift its feeding habits or behavior – suffer a sharp decline in population or become extinct
  50. 50. Predation One species hunts the other and uses it for food.
  51. 51. Predator-Prey Relationship
  52. 52. Parasitism
  53. 53. Density-Independent Limiting Factors • Operates equally well regardless of population size • Examples include: • Natural disasters like volcanoes, floods, etc. • Annual climate fluctuations • Produces “Boom or Bust” growth curves
  54. 54. Relationships in Ecological Communities
  55. 55. Symbiosis A relationship between 2 different species “Living together” 3 Types: • Parasitism • Mutualism • Commensalism
  56. 56. Parasitism Relationship where one species benefits and the other is harmed • 1st species (+) • 2nd species (-) Ex. Tick sucking blood from a dog
  57. 57. Mutualism Relationship where both species benefit from their interaction • 1st species (+) • 2nd species (+) Ex. Bee pollinates a flower
  58. 58. Commensalism Relationship where one species benefits and the other is unaffected • 1st species (+) • 2nd species (0) Ex. Cattle Egret