2. Environmental systems and societies
• Why is it called Environmental systems?
• The environment is seen as a set of complex
systems: set of components that function
together and form integrated units.
3.
4. •The following table compares, one by one, the traits of the two approaches.
Analytic Approach Systemic Approach
isolates, then concentrates on the unifies and concentrates on the
elements interaction between elements
studies the nature of interaction studies the effects of interactions
emphasizes the precision of details emphasizes global perception
modifies groups of variables
modifies one variable at a time
simultaneously
remains independent of duration of time; integrates duration of time and
the phenomena considered are reversible. irreversibility
validates facts by means of experimental validates facts through comparison of
proof within the body of a theory the behavior of the model with reality
uses models that are insufficiently
uses precise and detailed models that are
rigorous to be used as bases of
less useful in actual operation (example:
knowledge but are useful in decision and
econometric models)
action
has an efficient approach when has an efficient approach when
interactions are linear and weak interactions are nonlinear and strong
leads to discipline-oriented
leads to multidisciplinary education
(juxtadisciplinary) education
leads to action programmed in detail leads to action through objectives
possesses knowledge of details poorly possesses knowledge of goals, fuzzy
defined goals details
5.
6. Models
• Simplified description to show the structure or
workings of an object system or concept
• Illustrates flows, storages and linkages within
ecosystems.
• Models can show data quantitatively
• Examples …aquarium, graphs, computer
models
7. Advantages of models
• They allow scientists to predict and simplify
complex systems
• Inputs can be changed and outcomes
examined without having to wait for real
events
8. Disadvantages of models
• May not be accurate , climate models are
hugely complex
• Rely on the expertise of the people making
them
• Different people may interpret them in
different ways
• Any model is only as good as the data that
goes in and these may be suspect
