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Questions | Answers

1. 0.003%

2. 2/3 evapotranspires, 1/3 runs off, and 3% infiltrates into the groundwater.

3. First is agriculture, followed by industry and public/municipal

4. Define the following terms:

  • unsaturated zone: upper soil layer that holds both air and water
  • saturation zone: usually lower soil layer where all available pores between soil particles are filled with water
  • water table: the top of the zone of saturation
  • aquifer: groundwater that is economically retrievable
  • recharge area: where water is added to an aquifer
  • discharge area: where water is removed from an aquifer (e.g., wells, springs, rivers, etc.)
  • ground water mining: removing water from an aquifer faster than it is replenished (discharge rate greater than recharge rate).
  • watershed: the land area around a body of water over which water could flow and potentially enter that body of water.

5. pollute or decrease infiltration rates

6. problems associated with overpumping groundwater

  • Higher costs associated with digging deeper wells and pumping water farther up.
  • Lower water quality
  • Loss of habitat (loss of riparian habitat and species associated with springs, rivers, etc.)
  • Subsidence: as water is removed from the ground, the soil compacts and the surface sinks which damages structures (e.g., roads, pipes, buildings, etc.) and may lead to "permanent" loss of water holding capacity for the aquifer.
  • Saltwater intrusion: occurs in coastal areas when overpumping freshwater groundwater begins to suck salt water into an aquifer and saltwater gets pumped into wells.

7. Point sources of pollution are discrete, identifiable sources of pollution (e.g., pipe dumping polluted water into a stream) which are more easily monitored and enforced).
Nonpoint sources of pollution are diffuse or scattered sources (e.g., oil off roads) which are more difficult to monitor and enforce.

8. Three major types (stages) of wastewater treatment

  • Primary Treatment: physical/mechanical processes
  • Secondary Treatment: biological processes
  • Tertiary Treatment: processes used to remove specific pollutants

9. Effluent goes to the city for use in irrigation and the rest is dumped into the Santa Cruz River.
go to agriculture for fertilizer on non-food crops.