| A | B |
|---|
| aquifer | an underground layer of rock or soil that holds water |
| artesian well | a well in which water rises because of pressure within the aquifer |
| divide | a ridge of land that separates one watershed from another |
| eutrophication | the process by which nutrients in a body of water build up over time, causing an increase in the growth of algae |
| evaporation | when water is heated and changes from a liquid to a gas (water vapor) |
| groundwater | water that collects in pores in the soil and sinks into the ground |
| habitat | place where an organism lives and that provides for its needs |
| impermeable | preventing materials from passing through |
| irrigation | the act of supplying dry lands with water |
| levee | a long ridge formed by deposits of sediments alongside a river channel |
| permeable | allowing materials to pass through |
| photosynthesis | plants use energy from sunlight to produce their own food |
| pore | a small hole or open space |
| precipitation | water that falls to Earth as rain, snow, sleet, or hail |
| recharge | new water that enters the aquifer from the surface |
| reservoir | a place where water is stored |
| saturated zone | the area of permeable rock or soil that is totally filled, or saturated, with water |
| spring | a place where groundwater bubbles or flows out of cracks in rocks |
| transpiration | the process by which plants transfer water vapor to the atmosphere |
| tributary | a river or stream that flows into a larger river |
| unsaturated zone | a layer of rocks and soil above the water table in which the pores contain air as well as water |
| water cycle | the constant circulation of Earth's water |
| water table | the top of the saturated zone, or depth to the groundwater in an aquifer |
| water vapor | forms when liquid water changes to a gas |
| watershed | land area that supplies water to a river system |
