How and why do we deﬁne “the environment”?
Environment: is more than water, land and air, it is the sum of total of our surrounding (all living
and non –living)
• legal issues -- the environment is a legal entity
• environmental policies/practices need to be deﬁned by various organizations
• socially/culturally/philosophically -- how do we think about and relate to the
Has two components:
1. Abiotic: non-living
2. Biotic: living
Natural resources are vital to our survival:
• Renewable natural resources: natural resources that are replenish able over short periods
• Non-renewable resources: are in finite supply and are depletable because they are formed
much more slowly
• Resource Management: is strategic decision making and planning aimed at balancing the
use of resource with its protection and preservation
How we relate to environment:
Environmental Science: the study of how natural world works and how humans and the
Environmental science explores interaction between humans and the physical and biological
world: • encompasses the biogeocheicmal physical system in which peopleand other ogranisms
• dynamic interrelationships among organisms (including people) and their surroundings
(physical, chemical, biological, geological, social/cultural...)
Environmental issues are inherently interdisciplinary
Our understanding is greater than a “sum of the parts”
Environmental science is not the same as environmentalism:
• Environmentalism: a social movement dedicated to protecting the natural world
• Environmental science: is the study and knowledge of the workings of environment
Nature of Science:
• Science: systematic process for learning about the world and testing our understanding of
• The accumulated body of knowledge that arises from this dynamic process of
observation, testing and discovery
Scientists test ideas by critically examining evidence:
• The scientiﬁc method: a formalized method for testing ideas with observations that
involves several assumption and more or less consistent series of interrelated steps
• Scientific method relies on assumptions:
1. The universe works according to natural laws.
2. Events arise from causes, and cause other events.
3. We use logic, systematic testing, and our senses to understand natural laws.
• The scientiﬁc method is a key element of science
1. Make observations and ask questions.
2. Formulate hypotheses – preliminary explanations. 3. Use hypotheses to generate predictions – speciﬁc statements that can be tested.
4. Interpret test results – support or reject hypothesis.
• Scientific method:
2. Ask questions
3. Develop hypothesis
4. Make predictions
5. Test predictions:
• Experiment: activity designed to test vadilaity of a hypotheses
• It involves components:
I. Manipulating variables
II. Independent variable: a variable whose variation does not depend
on that of another.
III. Dependent variable: a variable whose value depends on that of
IV. Control variable: something that stays constant
• Tested many different ways: