1. Normal extinction of species that occurs as a result of changes in local environmental conditions?

2. Portion of solar radiation directed back into space as a result of particle scattering in the atmosphere?

3. Area behind the shore?

4. Sloping bank landward of the shore?

5. Marshy low lying area in a stream's floodplain?

6. The return water which flows back because of gravity?

7. Simple single celled prokaryotic organisms?

8. Characterized by deep ravines and gullies, shape ridges, and a generally barren surface?

9. Consecutive series of alluvial fans forming along the edge of a linear mountain range?

10. Collapse of stream bank material into a stream channel?