1. Ecology, Ecosystems, and the Environment

2. Ecology –Study of natural living systems Ecosystem –Includes all the living organisms and their non-living physical environment –Matter and energy are recycled –“Ecological Niche” refers to an organism’s particular way of obtaining matter and energy in an ecosystem –“Homeostasis” refers to the balance that occurs in an ecosystem when the resources must be shared among all individuals

3. Ecology, Ecosystems, and the Environment Food Chain –Recycling matter and energy –Trophic level determined by how close organism is to sun (1 st:: plants, 2 nd: whatever eats the plant, 3 rd: whatever eats the 2 nd, etc.) Organisms categorized by food source –Herbivore Eats plants –Carnivore Eats meat –Omnivore Eats both

4. Ecology, Ecosystems, and the Environment Biosphere –Zone of Earth where life is found Terrestrial biomes – land areas Aquatic life zones – water based areas –Biomes (land): Determined by temperature and precipitation Trees present –Rainfall is most important factor, minimal amount required –Includes »tropical (rainforest) »temperate (deciduous, but also rainforest and evergreens) »polar (evergreens) Without trees –Too little rain for trees –Includes »Deserts »Grasslands »Tundra »Chapparal

5. Ecology, Ecosystems, and the Environment –Aquatic life zones (water) Marine or Fresh –Determined by presence or absence of salt Marine –Includes »Oceans »Estuaries – occur where rivers empty into an ocean – mixture of salt and fresh water Fresh –Includes »Rivers, lakes, ponds streams, creeks »Underground aquifers

6. Ecology, Ecosystems, and the Environment –Threats to environments –Using up non-renewable resources –Certain resources cannot be replenished within human timeframe –Address by following the 3 R’s: Reduce / Reuse / Recycle –Turning resources into solid waste –Modern sanitary landfills not designed for biodegradation –Create less solid waste &/or treat waste as a resource –Creating pollution –Depletion of ozone layer –Acid rain –Air pollution and smog –Greenhouse gasses and global warming

7. Ecology, Ecosystems, and the Environment –POLLUTION –CFC’S Chemical primarily responsible for depletion of the ozone layer Developed in 1950’s – by 1986 it’s use was strictly regulated –Solid and Hazardous Waste Byproduct of modern industrialized civilization Must find better methods for disposal or reuse –Nitrogen oxides, sulfur compounds, and hydrocarbons Principal components of Acid Rain Primarily from the burning of fossil fuels –Smog Urban air pollution in lower level of atmosphere Due to several compounds including those which produce acid rain, as well as ozone and others which interact close to the earth’s surface Originate from such human activities as transportation, industry –Carbon dioxide, methane, CFC’s, water vapor “Greenhouse Gases” – hold heat from the sun in the atmosphere Natural greenhouse effect necessary to sustain life as we know it Human activity greatly increasing amount of CO 2 in atmosphere “Global Warming” is the increase in overall global temperature