chapter 12: Biodiversity Flashcards
forests
30% of the worlds land, an area where trees cover more than 10% of the land,
grasslands
1/4 of worlds land, converted to cropland, urban areas, disturbance 3 times that of tropical rain forest, threatened in rangelands than any other american biome, grazing (leads to desertification)
largest remaining areas of forest
cold, high latitude areas and humid equatorial areas
largest tropical forest
south america, 22% of worlds forest and largest undisturbed tropical rain forest
boreal forests
north america and eurasia have vast amount of undisturbed boreal forests
primary forests
old growth forests, composed of primarily of native species in which there is little indication of human activity and ecological processes are not significantly disturbed, 1/3 of worlds forests, 80% are experiencing unsustainable logging rates, at current deforestation rates, no forests will be left outside parks by the end of this century
successful reforestation programs
exist in china, korea, and japan
tropical forests
contain half of all plant, animal, and microbial species on earth
cause for deforestation
conversion of forest to agriculture, large scale commercial logging, fires, biofuel
forest protection
some places are being reforested, 12% are protected
brazil
leader in establishing forest reserves and allows traditional peoples to engage in non-destructive extraction of resources in the forest, people are protecting local forests
debt for nature swaps
conservation organizations buy debt obligations, then offer to cancel the debt if debtor country protects biologically important areas
threats to temperate forest
climate change, insect threats and wildfires, rising global temperatures trigger droughts which make trees more vulnerable to insect infestations and fires
fire-adapted communities
some biological communities require periodic burning for regeneration
ecosystem management
attempts to integrate sustainable ecological, economic, and social goals in a unified systems approach across landscapes over ecological time scales, considering human needs and sustainable economic development, maintaining diversity and ecosystem processes, adapt management over time through conscious experiment and monioring
overgrazing
grazing fees charged for use of public lands are below market value and represent a hidden subsidy to ranchers
rotational grazing
confines animals to small area for a day or two before shifting them to a new location
parks and preserves
12% of earth’s land is protected, some parks only exist on paper due to lack of funding
preserves not safe from exploitation
excessive stock grazing, dam building, oil drilling, mining, logging, coral reefs damaged by dynamite fishing, hunting; eggs from endangered sea turtles are taken by hunters, overuse by public
overuse of national park
entertainment over nature protection, fire suppression resulted in large fires, traffic congestion, surrounding areas mined or cleared, air pollution and smog, parks are profitable but do not keep money earned
world conservation strategy
developed by IUCN, maintain essential ecological processes and life support systems; preserve genetic diversity essential to improving cultivated plants and domestic animals; ensure utilization of wild species and ecosystems is sustainable
___% of nearshore territory should be marine refuge area
20%
90% of coral reefs are threatened by…
rising temperatures. destructive fishing, coral mining, and sediment runoff, if continues all will be gone in 50 years
largest marine reserve
the great barrier reef marine park in australia
