Environmental Science Chapter 1: Studying the State of Our Earth

 Environment  Environmental science  System  Ecosystem  Biotic/abiotic  Environmentalist  Environmental studies Let’s review some terms

 Are Earth’s life-support systems being degraded by human-induced changes?  Ecosystem services: clean water, timber, fisheries… ?  Indicators show the health and quality of a natural system – not necessarily the cause  Five to focus on in this course:  Biological diversity (genetic, species, ecosystem)  Food production  Global climate  Human population  Resource depletion Environmental Indicators

 Requirements: 1.Environmental systems cannot be damaged beyond their ability to recover 2.Renewable resources must not be depleted faster than they can regenerate 3.Nonrenewable resources must be used sparingly  Ecological footprint  Energy, settlements, timber and paper, food and fibers, seafood, carbon footprint, built-up land, forests, cropland and pastures, fisheries, minerals Sustainable practices

1.Observations and questions 2.Forming a hypothesis – what, exactly, is an ‘educated guess’?  Null hypothesis – the statement that can be proved wrong 3.Collecting data  Important considerations: replication, sample size, accuracy, precision, uncertainty 4.Interpreting results  Inductive reasoning versus deductive reasoning 5.Disseminating findings  Terms to keep in mind: critical thinking, theory, natural law The process of science

 Controlled experiment  One variable to test!  independent variable  One group gets the test!  experimental group  The test causes the result!  dependent variable  The other group allows us to compare!  control group  Natural experiment  A natural event acts as an experimental treatment in an ecosystem  Example: study of forest regrowth after a volcano Experimental design

 Lack of baseline data for comparison – there is no ‘control’ planet without humans  Subjectivity – one man’s trash is another man’s treasure… but what about the ecosystem?  Interactions – natural systems are extremely complex  Human well-being – people who are struggling to get their basic needs met are less concerned for environmental issues. These same people may be more impacted by environmental problems. Challenges of environmental science