| A | B |
| Silt | Bits if dirt and rock on river bottoms |
| subsistance farming | Raising enough food to feed one's family |
| elevation | height of land above sea level |
| tributary | a small stream or river that flows into a larger one |
| nomad | a person who moves around to make a living, usually herding |
| diversity | to add variety |
| irrigate | to artificially water crops |
| escarpment | a steep cliff about 100 stories high |
| cashcrop | crops which are raised to be sold |
| savanna | a region of tall grasses |