1. COLLEGE ENVIRONMENTAL SCIENCE MRS. CIRILLO CHAPTER 1 FUNDAMENTAL IDEAS OF ENVIRONMENTAL SCIENCE AND THE NATURE OF SCIENCE

2. OUR ISLAND, EARTH The Earth may seem enormous to us But Earth and its systems are finite and limited We can change Earth and damage its systems Environment : all the living and nonliving things around us Continents, oceans, clouds, ice caps Animals, plants, forests, farms, etc. Structures, urban centers, living spaces Social relationships and institutions

3. WHAT ARE THE FUNDAMENTAL PRINCIPLES OF ENVIRONMENTAL SCIENCE? We are part of the natural world, but we can also change it Our interactions with its other parts matter We depend completely on the environment for survival Natural systems have been degraded by pollution, soil erosion, species extinction, etc. Environmental changes threaten our long-term well- being and survival

4. ENVIRONMENTAL SCIENCE EXPLORES OUR INTERACTIONS WITH THE WORLD Environmental science is the study of: How the natural world works How the environment affects humans and vice versa Why do we need to understand our interactions with the environment? To creatively solve environmental problems Global conditions are rapidly changing We are also rapidly gaining knowledge We still have the opportunity to solve problems

5. WE RELY ON NATURAL RESOURCES Natural resources : substances and energy sources we need for survival Renewable natural resources : replenished over short periods Perpetually renewed: sunlight, wind, wave energy Renewed over short periods and can be depleted: timber, water, soil Nonrenewable natural resources : unavailable after depletion Oil, coal, minerals

6. WE RELY ON ECOSYSTEM SERVICES Natural resources are “goods” produced by nature Earth’s natural resources provide “services” to us Ecosystem services: arise from the normal functioning of natural services and allow us to survive Purify air and water, cycle nutrients, regulate climate Pollinate plants, receive and recycle wastes We degrade ecosystem services by depleting resources, destroying habitat, generating pollution Increased human affluence and population have intensified degradation

7. HUMAN POPULATION GROWTH AMPLIFIES IMPACTS There are now over 7 billion humans Agricultural revolution : 10,000 years ago Growing crops and livestock led to sedentary lives Stable food supplies increased survival and children Industrial revolution : mid 1700s Urbanized society powered by fossil fuels (oil, gas, coal) Sanitation and medicines Pesticides, fertilizers

8. THE NATURE OF SCIENCE Science: a systematic process for learning about the world and testing our understanding of it The body of knowledge arising from the dynamic process of questioning, observation, testing, discovery Knowledge gained from science can solve society’s needs Develop technology Inform policy and management decisions Scientists are motivated to: Develop useful applications Understand how the world works

9. APPLICATIONS OF SCIENCE Prescribed burning restores healthy forests Engineering and technology Energy-efficient electric car Policy and management

10. SCIENCE TESTS IDEAS BY EXAMINING EVIDENCE Science asks and answers questions Scientists do not simply accept conventional wisdom They judge ideas by the strength of their evidence Observational (descriptive) science : information is gathered about organisms, systems, processes, etc. Cannot be manipulated by experiments Phenomena are observed and measured Used in astronomy, paleontology, taxonomy, genomics Hypothesis-driven science : targeted, structured research Experiments test hypotheses using the scientific method

11. THE SCIENTIFIC METHOD: A TRADITIONAL APPROACH It tests ideas with observations A scientist makes an observation and asks questions about some phenomenon Hypothesis : a statement that tries to answer the question The hypothesis generates predictions : specific statements that can be directly tested

12. THE SCIENTIFIC METHOD TESTS HYPOTHESES Experiment : tests the validity of a prediction or hypothesis Variables : conditions that can change or be manipulated The data (information) are analyzed and interpreted By statistical tests The experiment either supports or rejects the hypothesis

13. EXPERIMENTS MANIPULATE VARIABLES Independent variable : can be manipulated Dependent variable : depends on the independent variable Controlled experiment : the effects of all variables are controlled Except the independent variable whose effect is being tested Control : an unmanipulated point of comparison Treatment : a manipulated point of comparison Quantitative data : information expressed by numbers Qualitative Data : information that describes something

14. HYPOTHESES ARE TESTED IN DIFFERENT WAYS Manipulative experiments : reveal causal relationships The independent variable is manipulated Yields the strongest evidence Long-term, large-scale processes can’t be manipulated Natural tests : search for correlations among variables Compare how dependent variables are expressed in different contexts Weaker evidence, but shows real-world complexity Results are not neat-and-clean, or black-and-white Addresses immense-scale questions (i.e., ecosystems)

15. THE SCIENTIFIC PROCESS: PART OF THE SCIENTIFIC COMMUNITY Peer review : other scientists judge the work Conferences : scientists interact with others Grants and funding : from private or government sources Intense competition Repeatability : others try to reproduce the results

16. THEORIES AND PARADIGM SHIFTS Theory : a well-tested and widely accepted explanation Extensively validated by great amounts of research Consolidates widely supported, related hypotheses It is not “just a theory” (speculation) Example: Darwin’s theory of evolution by natural selection With more data, scientific interpretations can change Paradigm shift : a new dominant view replaces the old Example: Earth, not the sun, is the center of the universe Example: plate tectonics move continents