1. Section 6.2 Unit 2- Ecology Ms. Nguyen

2. 6.2 soil resources Healthy soil supports both agriculture & forestry. “Topsoil”- mineral-rich portion of soil – When not maintained, can be lost Soil erosion- removal of soil or by water or wind

3. 6.2 soil resources DESERTIFICATION- lower land productivity caused by over-farming, overgrazing, seasonal drought, and climate change Ex: Expansion of Sahara desert

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5. 6.2 soil resources DEFORESTATION- destruction of forests – Creates negative impact on soil Trees don’t hold soil in place  soil erosion Ex: Amazon, Indonesia

6. 6.2 soil resources What can we do to minimize soil erosion? – Sustainable agriculture – Sustainable forestry

7. 6.2 Freshwater resources POLLUTANT- harmful material that can enter biosphere through land, air, or water – Ex: oil washed off roads by rain Primary sources of water pollution are: – Industrial and agricultural chemicals – Residential sewage – Nonpoint sources Example: Mercury, DDT

8. 6.2 Freshwater resources BIOLOGICAL MAGNIFICATION- increasing concentration of a harmful substance in organisms at higher trophic levels in a food chain or food web How do we ensure sustainable water use? – Protect natural water cycle – Control pollution – Conserve water

9. Common forms of air pollution: – Smog – Acid rain – Greenhouse gases – Particulates SMOG- gray-brown haze formed by a mixture of chemicals – Caused by chemical RXN involving sunlight and gases in atmosphere 6.2 Atmospheric resources

10. ACID RAIN- rain, snow, or fog* containing nitric and sulfuric acids – Caused when acidic compounds mix with water vapor in atmosphere – Can travel hundreds of miles What can we do to improve air quality? – Regulate emissions from cars & businesses – Carpool – Don’t burn trash 6.2 Atmospheric resources