APES Chapter 9
Dams and Salmon on the Klamath River - correct answer hydroelectric dams, in
conjunction with the drainage of two large lakes at the river's source for agriculture,
impeded the flow of water and prevented the natural migration of salmon to their
breeding grounds; conflict over water use between farmers, fisherman, Native
Americans, industry, etc. led to overuse and exploitation of this resource and
massive fish kills (increased temperatures, disease, toxic algae); the dams are
scheduled to be removed in 2020
distribution of water on Earth - correct answer 97% saltwater, 3% freshwater (1/4
underground, almost 3/4 frozen, remaining <1% accessible for human consumption)
aquifer - correct answer small spaces found within permeable layers of rock and
sediment where groundwater is located
unconfined aquifer - correct answer porous rock covered by soil which water can
easily flow in and out of; rapidly recharged by percolation of precipitation
confined aquifer - correct answer aquifer surrounded by a layer of impermeable rock
or clay that impedes water flow and causes water pressure to build up underground
water table - correct answer uppermost level at which the water in a given area fully
saturates the rock or soil
groundwater recharge - correct answer the input proces by which water from
precipitation percolates through the soil into an aquifer
recharge area - correct answer opening at the surface of the otherwise impermeable
layer covering a confined aquifer
spring - correct answer source where water naturally percolates up to the ground
surface; crucial to the organisms in freshwater aquatic biomes and can be used by
humans for consumption
