Science & The Environment Section #1: Understanding Our Environment

What exactly does the term ENVIRONMENT mean? includes everything around you natural world things produced by humans more that just what can be seen by the naked eye complex web of relationships – everything is connected to everything else

Discussion Question: It is often difficult for people to reach an agreement about environmental issues. Why?

What is Environmental Science? the study of how humans interact with the environment major goal = to understand & to solve environmental problems focus on how we use natural resources & how our actions alter our environment

Fields of Study Biology – living organisms (zoology, botany, microbiology, ecology) Earth Science – nonliving systems (geology, paleontology, climatology, hydrology) Physics – matter & energy (engineering) Chemistry – chemicals & their interactions (biochemistry, geochemistry) Social Sciences – human populations (geography, anthropology, sociology)

An Interdisciplinary Science One field plays a key role . . . Ecology – the study of how living things interact with each other and with their nonliving environment

How Have We Changed Our Environment Over Time?

How Have We Changed Our Environment Over Time? Hunter-Gatherers small groups that migrated to find food burned prairies to maintain open grasslands for some species spread plants to other areas over-hunting lead to disappearance of some species (mass graves)

How Have We Changed Our Environment Over Time?

How Have We Changed Our Environment Over Time? Agricultural Revolution (10,000 yrs. ago) stopped migrating, staying in one place smaller areas could support greater populations leading to rapid population growth saved seeds of the “good” plants, leading to the domestication of wild plants slash & burn destroyed habitats, leading to soil loss, flooding, water shortages over time the fields lost fertility

How Have We Changed Our Environment Over Time?

How Have We Changed Our Environment Over Time? Industrial Revolution (mid 1700s) shift in animal power to fossil fuels how did this change society? how did this change the efficiency of agriculture industry transportation

Discussion Question: How have the things that make life easier also lead to more problems? What are some more recent problems we’re facing as technological advances continue?

What is a CLOSED system? Earth – it cannot get rid of used material nor can it take on new supplies What problems do you see on a local scale? regional scale? global scale?

Compare the differences in population growth in the past 50 years Compare the differences in population growth in the past 50 years. Why do you think this is happening?

Population Growth being able to produce more food & transport that food to a sprawling nation has spurred a growth in the world’s population improvements to modern medicine & sanitation have also added in the survival rate

Graph – Population Growth

What are Our Main Environmental Problems? Resource Depletion Pollution Loss of Biodiversity

Resource Depletion Renewable vs. Nonrenewable Any natural resource, renewable or nonrenewable, can become depleted when a large fraction of the resource has been used up

Pollution An undesired change in air, water, or soil that adversely affects the health, survival, or activities of humans or other organisms Name some forms of pollution from human activites

2 Types of Pollutants Biodegradable = can be broken down by natural processes (ex. include human sewage & a stack of newpapers) Nondegradable = cannot be broken down by natural processes (ex. include mercury, lead, some types of plastic)

Loss of Biodiversity Extinctions, even mass extinctions, are a natural process & have occurred many times in Earth’s history Some scientists believe the rate of current extinctions is high & this may cause problems for humans down the road