AP Enviro Chp 10
how are the california condour and the red wolf similar?
they were both taken out of the wild and put in captive breeding programs
number one threat to red wolfs at first; number one threat now
crossbreeding with coyotes; people killing them
what could happen to you if you kill or are caught with something protected by the endangered species act
one year in jail and $100,000 fine
when was yellowstone established?
the zone immediately along or next to a river or stream
why is the gray wolf a keystone species?
they affect water quality; they eat elk but when they aren't there the elk eat the vegetation in the riparian zone and causes erosion and increased turbidity
how many virgin forests have been logged in the US?
how many wetlands in the US have been filled
how many prairies in the great plains have disappeared?
forests cover __% of the land surface
list 4 ecological services of forests
reduce soil erosion, purify water and air, store atmospheric carbon, absorb and release water
list 4 economic services of forests
lumber, mining, recreation, paper
the 3 types of forests
old growth, second growth, tree plantation
uncut or regenerated forest that has not had significant impact in several hundreds of years.
what percent of forests are old growth?
where are some old growth forests?
russia, canada, brazil, indonesia, new guinea
stand of trees resulting from natural secondary succession following removal of human activities or natural forces
what percent of forests are secondary growth?
a managed tract or uniformly aged trees of one or two species that are harvested by clear cutting as soon as they become commercially valuable. the land is then replanted and then clear cut again
how many forests are tree plantations?
intermediate-aged or mature trees in an uneven aged forest are singly cut or in small groups. this reduces crowding, removes diseased trees, maintains many kinds of different species
form of selective cutting in which all the largest trees are removed
2 good things about strip-cutting
it helps erosion and doesn't completely destroy a habitat
the US national forest system contains ___ national forests
usually burn only undergrowth and leaf litter on the forest floor
3 good things about fires
burn out invasive underbrush, release nutrients, release seeds from pinecones and other plants
2 fire dependent systems
grasslands and chapparal
the old fire policy
fire suppression (put out every fire)
the new fire policy
only put out fires that dont do anything good for the environment
rainforests make up _% of the earth's surface
primary causes of tropical deforestation
logging, ranching, agriculture (cash crops), population growth
converting deforested areas into tropical grassland (savanna)
decline in productivity
grasslands in the west; in the east
cattle are confined by portable fencing to one area for a short time and then moved to a new location