1. APES Warm-Up (11/18) 1.What are three things you already know about farming? 2.What does sustainability mean to you? 3.What are 3 ways we could make farming more sustainable?

2. Weathering Slides AP Environmental Science

3. Weathering – processes that break down rocks, turning large particles into smaller particles Three main types: – A. physical (mechanical) weathering – B. chemical weathering – C. biological weathering

4. Mechanical Weathering: no change in chemical composition--just disintegration into smaller pieces

5. Chemical Weathering: breakdown as a result of chemical reactions CaCO 3 +CO 2 +H 2 O ---> Ca 2+ + 2HCO 3-

6. Shattered rocks are common in cold and alpine environments where repeated freeze-thaw cycles gradually pry rocks apart.

7. Holes created as a result of chemical weathering

8. Biological Weathering Can be both chemical and mechanical in nature. roots split rocks apart lichens produce acids that dissolve rocks. burrowing animals