| Term | Definition |
|---|
| the roles that world forests play | regulating climate,controlling water runoff,providing food and shelter for wildlife,purifying air,provide valuable materials (wood,paper-pulp),scenic,cultural , and historic value. |
| forest distribution | 9.6 billion acres,more than 10% of land |
| old growth forests | areas that have been undisturbed by human activities long enough that trees can live out a natural life cycle,only 25% still retain old growth charactersitics,10% remains intact ,80% of what is left is scheduled to be cut down |
| forest products | total annual wood consumption is 3.7 billion metric tons,100$ billion each year,developed countries produce less than half of all industrial wood but account for 80% of consumption,developed countries are largest producers of wood and paper pulp,more than half of world's population depends on wood for survival |
| forest management | 25% of world's forests are managed for wood production,sustainable harvest is key to regeneration,monoculture forestry |
| monoculture forestry | planting the same species of trees,decreases diversity,rapid growth and easier harvest,disrupts ecological processes |
| tropical forests | occupy less than 10% of land,contain more than 2/3 of all higher plant biomass,1/2 of all plant,animal and microbial species in the world |
| diminishing forests | tropical forests are shrinking rapidly,0.6% of remaining forest is cleared annually ,estimates are very rough,countris have economic and political reasons to hide extent of losses,real losses may range from 5-20 million ha annually ,brazil has largest rainforests and highest rate of deforestation |
| causes of deforestation | thin,nutrient poor tropical soils are usually worn out after few years of cropping,shifting cultivation blamed for forest destruction,can be sustainable where pop. densities are low & plots are allowed to regenarate between cultivation periods. |
| debt-for-nature swap | conservation organization buy debt obligations and then offer to cancel debt if the debtor country will agree to protect or restore an area of biological importance. |
| temperate forests | above the equator,northern countries have history of liquidating forest resources,multiple use,simultaneous use, |
| harvest methods | clear-cutting,shelterwood,strip cutting,selective cutting |
| clear cutting | every tree in an area is cut down for harvesting,fast and efficientbut wastes small trees,icreases erosions and elminate wildlife habitat |
| shelter-wood | removes mature trees in series of cuts,most ecologically friendly |
| strip cutting | harvesting all trees in a narrow corridor |
| selective cutting | a small percentage of mature trees are taken in10-20 year rotaion |
| logging and roads of national forest | people from the us care callng for an end to all logging on federal lands,4$billion annual havest verses estimated 224% billion from recreation and ecological function,usfs builds roads in order to timbercompanies to extract tres,hidden subsidy ti timber industry |
| fire management | 40% of all federal forest land is at risk of fires due to poor managment,68230 fires burned 2.7 million ha in 2002,firefighting costs 1.2$ billion |
| ecosystem management | 1990's saw shift from timber production to ecosystem management |
| rangelands | pasture and open range occupy 25% of world's land surface,3 billion domestic livestock producing meat and milk,attractive and frequently converted to human-dominated landscapes ,have the highest number of threatned plant species |
| desertification | it has reccently accelerated by expanding programs and political conditions that force people to overuse fragile lands,conversion of one community into a desert |
| overgazing in rangelands of the u.s. | overgazing has allowed populations of unpalatable or inedible species to build up on both public and private rangelands,grazing fees charged for use of public lands are often far below market value |
| animal units months | the amount of forage needed for one cow-calf pair for 1 month or five sheep, 1.97$ per AUM |
| new approaches to ranching | short-duration rotational grazing,game ranching |
| short-duration rotational grazing | an approach to ranching,forces livestock to graze equally, trample ground evenly, and fertilize with manure before moving on. |
| game ranching | many wild species forage more efficiently ,resist harsh climates,and can fend off predators and pests better than domestic livestock,using bison and buffalo rather than cows and sheep |
| origins and history of parks and nature preserve | sacred groves were set aside for religious purposes and grounds preserved for royalty,in the past 130 years we have begun to preserve wild places for the sake of wildlife and scenic beauty |
| yellowstone | first u.s. area set aside to protect wild nature,authorized by abraham lincoln,designated the first national park by president ulusses S. Grant in 1872,also first national park in the world |
| north american parks | u.s. park system 280000km2 in 376 parks,monuments,historic sites and rec. areas,300 million visitors annually,canada has 1472 protected areas occupying 150000km2 |
| park problems | human population crowd park boundaries,park rangers spend more time fighting crime than natural history,mining and oil intrests push to operate on private inholdings |
| wildlife issues | parks killed wolves in favor of elks caused unbalance in ecosystems and created false illusion of a natural system |
| parks as ecosystems | one of the biggest problems is that boundaries are often based on politics rather than ecological considerations,airsheds,watersheds and animal territories and migration routes often extend far beyond official boundaies ,biogeographical area must be managed as a unit |
| world parks and preserves | in many cultures,wilderness and wild lands are regarded as useless wastelands ,many preserves are too small to maitain sgnificant biological populations over the long term,about 300 biosphere reserves have been designated in 75 countries |
| marine preserves | shelter marine organisms from destructive harvest methods,coral reefs are among most theatned marine ecosystems |
| threats of coral reefs | from sea temperature change,destructive fishing methods,coral mining,sediment runoff,and othe human disturbance |
| size and design of nature preserves | single layer or several small (sloss) ,larg enough to support viable populations of endangered species,keep ecosystems intact,and isolate critical core areas from external forces |
| spectrum of preserves | recreation areas,historic areas,conservation reserves,pristine research areas,inviolable preserves |
| corridors | allow movement of species from one area to another can help maintain genetic exchange in fragmented areas |
| conservation and economic development | tropics are suffering greatest destruction an species loss in the world,ecotourism can be more beneficial to many countries over thelong-term than extractive industries,wildlife watching and outdoor recreation can be a welcome source of income for underdeveloped countries |
| indigenous communities and reserves | areas chosen for nature preservation are often traditional lands of indegenous people, MAB |
| MAB | man and biosphre program,initiated by unesco in 1986,encourages division of protected areas in zones with differet purposes |
| wilderness areas | an area of undeveloped land affected primarly by the forces of nature where man is a visitor who does not remain,most aras meeting these standards are in the western u.s. and alaska(according to 1964 wilderness act) |
| arguments for wilderess preservation | refuge for endangered wildlife,solitude for primitive recreation,baseline for ecological research,area left in natural state |
| wildlife refuges | 1901 roosevelt established 51 national wildlife refuges(1st is pelican island) ,now 511 refuges(40 million ha) |
| number of uses allowed to operate within wildlife refuges boundaries | oil and gas drilling,cattle grazing,motor-boating ,camping,expending human populations,water pollution |
| closed-canopy forest | tree crowns cover most of the ground |
| percentage of forests under protection | 12%. world's land area 10% |
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