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1 World Forests
Pages 21-36

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From page 21... ... The coniferous forests of North America and Eurasia cover an estimated 1.3 billion ha, other temperate forests about 1.1 billion ha, and tropical forests about 1.7 billion ha. LOSSES IN FORESTS Although major losses have also occurred in temperate forests, the greater concern is about losses in the moist tropical forests, which comprise the most complex, species-rich ecosystems in the world (Office of Technology Assessment, 1984~. Read the entire page →
From page 22... ... _ CD ~ O O O _ O ,,, _ 5J ~ O =0 ~, ~ ~ ,= U ~ cn ~ O ~ � cn cn cn au a; U ~ U ~ ~ X C ~ ._ ~ ._ cn ~ ~ Q ~ a; O 2 ~ ~ O ~ ._ E~ ~ (J) Read the entire page →
From page 23... ... About 36 percent of the tropical forests that have been degraded by removal of natural vegetation and overcropping could still be rehabilitated with the introduction of tree species. This includes 418 million ha in dry or montane areas in need of reforestation, 137 million ha of tropical rain forest in need of protected regeneration, and 203 million ha of forest fallows in the humid tropics in need of reforestation (Wood et al., 1982~. Read the entire page →
From page 24... ... Thei/~ge on~thel~ts~h~o~s a Action of Rondos on }sly ~ 1973, data 8B>364~ppea~d.~ ash white Recoin the upper fight. Note thelakeinthelbw~rleft.D~(ka~as Spa mat ~ ~sts.The ~hitea~rea that USA ~ ~ ~ natal gushes off food , drugs, Fuel.. Read the entire page →
From page 25... ... a: ~ ~ ~ ~ ~ ^~ ,~ / ~ a: s ~ ~ :~ w51 ~ ~ if:= ! O a: at the end of the Bag is cloud Over. Read the entire page →
From page 26... ... In ~r=~nv alone more than 1 000 ~ - ~ ~ ~ -- >_ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ , g~e=~n~spons~dpr~edsareexamin~gthee~sof Mouton on~rests.TheExecu~veBoardoft~helLFROhasestablishedaSpeC-ia1 skFo~eonPoLubon~c~~ina~ Sea hand ~=nabononth~ problem,and~r~ev~ie~softhestateofFno~ledge~ere~ maior~partof its Todd Congress in Montreal dud Lao. AdditionalI< concern has been Using about the consequences to the ~orld's Fasts of potential y~lobaI Harming attendi~n& the dest~r~c-tion of the earth's ozone layer. Read the entire page →
From page 27... ... ~ ~ /27 La~e~scale clowns of ~1~1 clan ~rest IBM fine Amazon Plasm, Colas, cam, never Me Rio T~n~tins, yes photdg~phed in 1~. Clad ec~ngles 3~ plant ions whew natu^1 woodland fleas ~pid~lv being convert to pastureland far Male Branching and a~^l~t~1 land far Swoops, such as maize and bung calve. Read the entire page →
From page 28... ... / ~i ~ ~ over zing and fiddler doIle~io! n, -aim ~bE#~z (accident fir d~l~ra~, and :~: Tat first Our activities age the mast si~niica~pt -~ a {o~}.~p~rs~pe~bv~ ~~d her. Read the entire page →
From page 29... ... (~e the multi~ple-populatio~n breeding stately described by {mkoon~ et al.' 1980. ~ Cn.fo~rt~.~nate~ly, sow ~eneLc looses cannot be~reco~u~ped because current prod~ctio~nis often not backed up by the holding cf ex~nst/e oft coercions of esed ages or by enamor ewes to conga va^bon ~ name sandy ~ spades or a population sample of a Or pan of in genetic Godson An ~ consumed though in ~ or ax ~# consent. Read the entire page →
From page 30... ... The sdenb~st Aced Bin the challenge ~ deadly toes that are suited to pa~c~lar news, sum as s~t~ight~oE~in~ Fees far l~um~r nut, ~ ~ ~ mat Isis the deified gene far bring pawns. lf the need is ~, edgily observable cha~ctedsS^, such as plant Boa, it is very simple to select tams with the fight genes. Read the entire page →
From page 31... ... It may be applied to reproductive material, such as seeds preserved in a seed bank, or to trees planted in arboreta, botanical gardens, or test or conservation stands away from the site of the parent population. Ex situ and in situ conservation are complementary strategies. Read the entire page →
From page 32... ... Most trap sp~ies am at a very p~mit~ive stage of genetic selection front wild types compared with a~hc~ltu^1 caps, some of Bach have past Daub th~=nds ~ Bunions ~ Domesday= and up ~ a ~- Ids ~ ~ Id. Read the entire page →
From page 33... ... Third, rotations of planted tree crops normally extend over many years, which creates difficulties in assigning variable discount and inflation rates. Given high-establishment costs in the early years and low-product values in later years, forestry projects always appear poor investments unless their socia! Read the entire page →
From page 34... ... TO extent to Shah existed or newly planted Masts could Duct ~tbe a~o~hedc wonton of this As mains a super Sac at I and degas cadre general abetment exists about tbe ^k Preen Crest decay and ~ll~ud~. H~ it i~ dolt to a~ ~elv He en~ron menial and physic pathways that are acted ~ Militants. Read the entire page →
From page 35... ... World Forests / 35 species described during the preparation of the flora of the Rio Palenque field station in Los Rios Province are now found only in the field station, which covers an area of less than 1 km2 (Gentry, 1986~. Greatly improved data on inventory are needed, particularly for tropical and subtropical regions. Read the entire page →

From page 21...

... The coniferous forests of North America and Eurasia cover an estimated 1.3 billion ha, other temperate forests about 1.1 billion ha, and tropical forests about 1.7 billion ha. LOSSES IN FORESTS Although major losses have also occurred in temperate forests, the greater concern is about losses in the moist tropical forests, which comprise the most complex, species-rich ecosystems in the world (Office of Technology Assessment, 1984~.

1 World Forests Pages 21-36

1 World Forests
Pages 21-36