This document provides an overview of key concepts in environmental management and science. It discusses the multidisciplinary and interdisciplinary approaches to environmental science. It also describes the structure and functions of environments and ecosystems, including the ecosystem concept. Modeling of environmental systems is mentioned as well as analyzing ecosystem stability, biodiversity, biosphere cycles, environmental limits, and the concept of environmental crisis. Resource classification and management of different environments are also summarized.

1. ENVIRONMENTAL
MANAGEMENT AND
SCIENCE
CHAPTER 3

2. ● Environment and environmental science
● Structure and function of the environment
● Environmental and ecosystems modelling, the ecosystem
concept,
environmental systems and ecosystem management
● How stable are environments?
● Biodiversity
● Biosphere cyclic processes
● Environmental limits
● Environmental crisis
● Summary
● Further reading

3. Environment and environmental
science
• When environmental management makes use of
science it can adopt one of two broad approaches:
(1) multidisciplinary – which involves
communication between
various fields but without much of a breakdown of
discipline boundaries;
(2) interdisciplinary (even holistic) – the various
fields are closely linked
in an overall, coherent way.

6. Structure and function of the
environment
• Modern definitions include: the study of the
structure and function of nature; the study of
interactions between organisms (biotic) and their
non-living (abiotic) environment; the science of
the relations of organisms to their total
environment (Fraser-Darling, 1963; Odum, 1975;
Park, 1980).

9. The ecosystem
• The biosphere is composed of many interacting ecosystems
(ecological systems), the boundaries between which are often
indistinct, taking the form of transition zones (ecotones), where
organisms from adjoining ecosystems may be present together. It is
possible for some organisms to be restricted to an ecotone only.
Large land ecosystems or biomes (synonymous with biotic areas) are
areas with a prevailing regional climax vegetation and its associated
animal life, in effect regional-scale ecosystems. Biomes, such as
desert biomes or grassland biomes, often mainly reflect climate, but
can also be shaped by the incidence of fire, drainage, soil
characteristics, grazing, trampling and so on (Watts, 1971: 186).

13. Environmental and ecosystems modelling, the
ecosystem concept, environmental systems and
ecosystem management
• Once understood and monitored, environmental
systems may be modelled using a variety of
approaches, including theoretical, physical,
analogue or computer models. A large and
diverse environmental modelling field has
emerged, specializing in anything from sediment
transport to hydrology, groundwater, global
climate change, carbon sequestration, ocean–
atmosphere energy and chemical flux – and
many other specialisms (Jakeman et al., 1993).

16. Ecosystems analysis, modelling and
monitoring
• Ecosystems (and environmental systems) may be
analysed using systems theory, which enables
complex, changing situations to be understood
and predictions made. Systems theory assumes
that measurable causes produce measurable
effects. There have been attempts to combine
ecological and economic models in systems
analysis.

17. Environmental system and ecosystem planning and
management – biogeophysical units
• Ecozones

18. • Ecoregions and Eco districts
• Coastal zone planning and management
• Marine ecosystem planning and
management

20. •River basin planning and management
•Watershed/catchment planning and
management
•Bioregionalism

21. Agroecosystem analysis and
management
• An agroecosystem is an ecosystem modified by humans
in order to obtain food or other agricultural produce.
• Four agroecosystem properties were recognized by
Conway (1985b):
1. Productivity
2. Stability
3. Sustainability
4. Equitability

22. • Landscape ecology approach-Landscape ecology is the science of
studying and improving relationships between ecological processes in
the environment and particular ecosystems. This is done within a
variety of landscape scales, development spatial patterns, and
organizational levels of research and policy.
• Ekistics- concerns the science of human settlements, including
regional, city, community planning and dwelling design. The study
involves every kind of human settlement, with particular attention to
geography, ecology, human psychology, anthropology, culture,
politics, and occasionally aesthetics.

23. • How stable are environments?
‘Stability’ can have a number of meanings, including: lack
of change in the structure of an ecosystem; resistance to
perturbations; or a speedy return to steady state after
disturbance (Troumbis, 1992: 252).

25. BIODIVERSITY
• The variety of life in the world or
in a particular habitat or
ecosystem.
• Biodiversity (biological diversity)
refers to species diversity plus
genetic diversity within those
species.

27. BIOSPHERE CYCLIC
PROCESSES
Within the biosphere, numerous
cyclic processes move and
renew supplies of energy, water,
chemical elements and
atmospheric gases.

28. ENVIRONMENTAL LIMITS
• The population reaching a limit may suffer gradual or
sudden, limited or catastrophic collapse in numbers, a
vacillation, or a cyclic boom-and-bust growth pattern.
• The boundary beyond which exploitation of a natural
resource will have significant deleterious effects Natural
resources include land, water, air and associated living
systems that comprise the biosphere. These can be
classified into ecosystems.

30. RESOURCES• Is a source or supply from which benefit is
produced. Resources are two types based
upon their availability they are renewable and
non renewable resource s.Typically resources
are materials, energy, services, staff,
knowledge, or other assets that are
transformed to produce benefit and in the
process may be consumed or made
unavailable. Benefits of resource utilization
may include increased wealth or wants,
proper functioning of a system, or enhanced
well being
• A resource may be defined as: ‘something
which meets perceived needs or wants

31. THEORY, PRINCIPLES
AND KEY CONCEPTS
• demographic transition (to marked slowing or even
negative population growth) is happening more rapidly
in developing countries than it did in the past in nations
such as France or Russia. It is unwise to wait and see
what business as usual will bring (i.e. little or no
significant change in development behaviour), and
better to seek stronger controls on resource use.

32. A rough classification of resources useful for
environmental management is as follows:
•those that can be safely and easily
stretched by humans;
• those that can be stretched with care;
• those that cannot or should not be
stretched

33. ENVIRONMENTAL
CRISIS?
The cause is usually identified as one
or a combination of the following:
people’s cavalier use of nature; over-
population; misapplication of
technology; faulty development
ethics. What is perceived to be a
crisis is subject to changing beliefs,
fashion, technological ability and so
on.

35. One may recognise several categories of perceived crisis (the
following are not arranged in order of importance, do not
represent a comprehensive list, nor are they all wholly separate
and discrete):
1. Renewable resource depletion and degradation
(especially shortfall in food production,
problems with water, and energy supplies);
2. Global environmental change;
3. Pollution;
4. Nuclear or biological warfare;
5. Biodiversity loss;
6. Increasing hunger & puberty;

36. 7. Increasing hunger and poverty;
Increasing human repression, marginalization and
disempowerment;
8. Rapid, often poorly planned, urban growth;
9. Increasing population – this caused more concern in
the 1970s than now;
10. Debt burden – some regions may have problems
due to debt repayment or structural adjustment
measures introduced to counter it.