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acid rain

rain containing sulfuric acids

aquatic biomes

underwater ecosystems *

aphotic zone

permanently dark layer of the oceans below the photic zone


having insufficient rainfall to support agriculture *


organisms that live attached to or near the ocean floor


group of ecosystems that have the same climate and dominant communities


part of earth in which life exists including land, water, and air or atmosphere

clear cutting

cutting all the trees in an area down at once *

cold desert

A desert that is low in temperature

coniferous forest

forest populated by cone-bearing evergreen trees


wise management of natural resources, including the preservation of habitats and wildlife

deciduous forest

a type of forest characterized by trees that seasonally shed their leaves


destruction of forests


dry land with little or no vegetation


wetlands formed where rivers meet the ocean

glacial lake

A lake that gets much or all of its water from the melting of glacier ice.


a large area of land covered with grasses.


water that fills the cracks and spaces in underground soil and rock layers


atmosphereic layer in which ozone gas is relatively concentrated


layer of permanently frozen subsoil in the tundra

photic zone

well-lit upper layer of the oceans


a forest with heavy annual rainfall


very dry with little rainfall

surface runoff

Water flowing off the land into bodies of surface water. See reliable runoff.


biome in which the winters are cold but summer are mild enough to allow the ground to thaw

terrestrial biomes

Biomes on land (forests, taiga, tundra, etc.)


a vast treeless plain in the arctic regions between the ice cap and the tree line


ecosystem in which water either covers the soil or is present at or near the surface of the soil for at least part of the year

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