CWD: Earth's Resources-Water

4. the area of an aquifer
7. the process of moving water from its natural source to fields and homes
8. water found below the Earth's surface
11. the process of landscaping with plants that require less water
12. layers of rock and soil that have few to no spaces or pores for water movement
14. man-made lakes that occur after a dam has been placed
15. an obstruction placed across a river or stream to block the flow of water
16. a hole dug into an aquifer
19. a sudden explosive growth of algae
20. areas of sponge-like rock, sand, or gravel that holds water underground
21. relatively pure water with few dissolved salts and makes up less than 3% of Earth's water
23. water found above ground
24. a system of channels that form due to water moving downhill
25. the removal of salt from ocean water
26. a build up of salts in soil layers
27. water that has not been absorbed by the ground and moves along the surface

1. when waste comes from many places like runoff
2. all of the land that contributes its water to a given river system
3. the boundary between layers of aeration (water can pass through) and saturation (water held)
5. a reddish algal bloom that can release toxins
6. a system put in place to dispose of human wastewater
9. when waste comes from distinct locations like a factory
10. eutrophication that occurs faster because humans dump wastes that increase the process
13. layers of rock and soil that have spaces or pores through which water moves
17. disease-causing organisms and viruses
18. used water
22. the natural process of increased algae and plant growth which can take long periods of time