Definition of Deforestatio1

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Definition of Deforestation

What is deforestation? The green definition of deforestation is the destruction

of a forest and changing the use of the land.

Many people are concerned about the fact that there is no official or common

definition of deforestation. For instance, should it also be used to describe

forests where the nature of the trees have changed, such as replacing slow

growing indigenous trees with fast growing woods, meaning that the precious

eco-system of the forest is destroyed?

Deforestation is the conversion of forested areas to non-forested land, for

uses such as: pasture, urban use, logging purposes, and can result in arid

land and wastelands. The removal or destruction of significant areas of forest

cover has resulted in an altered environment with reduced biodiversity. In

many countries, deforestation is ongoing and is shaping climate and

geography. Deforestation results from removal of trees without sufficient

reforestation, and results in declines in habitat and biodiversity, wood for fuel

and industrial use, and quality of life. Forests disappear naturally as a result

of broad climate change, fire, hurricanes or other disturbances, however

most deforestation in the past 40,000 years has been anthropogenic. Human

induced deforestation may be accidental such as in the case of forests in

Europe adversely affected by acid rain.[1] Improperly applied logging,

fuelwood collection, fire management or grazing can also lead to

unintentional deforestation.[2] However, most anthropogenic deforestation is

deliberate.

The consequences of deforestation are largely unknown and the impacts not

verified by sufficient scientific data [3] leading to considerable debate

amongst scientists.

Use of the term deforestation

The lack of specificity in use of the term deforestation distorts forestry

issues.[4] The term deforestation is used to refer to activities that use the

forest, for example, fuel wood cutting, commercial logging, as well as

activities that cause temporary removal of forest cover such as the slash andburn technique, a component of some shifting cultivation agricultural

systems or clearcutting. It is also used to describe forest clearing for annual

crops and forest loss from over-grazing. Some definitions of deforestation

include activities such as establishment of industrial forest plantations that

are considered afforestation by others. The term deforestation is such an

emotional term that is used "so ambiguously that it is virtually meaningless"


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unless it is specified what is meant.[5] More specific terms terms include

forest decline, forest fragmentation and forest degradation, loss of forest

cover and land use conversion.

The term also has a traditional legal sense of the conversion of Royal forest

land into purlieu or other non-forest land use.

Causes of anthropogenic deforestation

In simple terms deforestation occurs because forested land is not

economically viable. Increasing the amount of farmland, wood extraction

and, infrastructure expansion are all important factors in driving

deforestation in different regions [6] with mining also an important cause. [7]

There is considerable interplay between theaw factors. For example

logging(wood extraction) or mining requires roads to transport the

timber(infrastructure expansion) and farmers use these roads to move into

previously unreachable areas of forest (agricultural expansion). The ultimate

cause of most deforestation is increased food production. Cattle, permanent

crops, shifting cultivation and colonization are all equally important to global

tropical deforestation[8],

Forested land can not produce as much food as cleared land. At the extreme,rain forests can not support human populations at all because the food

resources are too scattered. However even in open forest and woodland

communities food production can be increased by orders of magnitude when

trees are removed. The planet could not support current population and

current living standards without if deforestation had never occurred [9].

Cattle, permanent crops, shifting cultivation and colonization are all equally

important causes of global tropical deforestation [10]. Slash-and-burn is a

method sometimes used by shifting cultivators to create short term yields

from marginal soils. When practiced repeatedly, or without intervening fallow

periods, the nutrient poor soils may be exhausted or eroded to an

unproductive state. Slash-and-burn techniques are used by native

populations of over 200 million people worldwide.


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While forests have potential value as carbon sinks or biodiversity reserves

the benefits of these are insufficient to justify the loss of income from forests.

Indeed the presumed value of forests as a genetic resources has never been

confirmed by any economic studies [11]. As a result owners of forested land

lose money by not clearing the forest and this affects the welfare of the

whole society [12]. From the perspective of the developing world, the

benefits of forest as carbon sinks or biodiversity reserves go primarily to

richer developed nations and there is insufficient compensation for these

services. As a result some countries simply have too much forest. Developing

countries feel that some countries in the developed world, such as the United

States of America, cut down their forests centuries ago and benefited greatly

from this deforestation and that it is hypocritical to deny developing

countries the same opportunities: that the poor shouldnt have to bear the

cost of preservation when the rich created the problem [13].

Aside from a general agreement that deforestation occurs to increase the

economic value of the land there is no agreement on what causes

deforestation. Logging may be a direct source of deforestation in some areas

and have no effect or be at worst an indirect source in others due to logging

roads enabling easier access for farmers wanting to clear the forest: experts

do not agree on whether logging is an important contributor to global

deforestation [14] and some believe that logging makes considerable

contribution to reducing deforestation because in developing countries

logging reserves are far larger than nature reserves [15]. Similarly there is no

consensus on whether poverty is important in deforestation. Some argue

that poor people are more likely to clear forest because they have no

alternatives, others that the poor lack the ability to pay for the materials and

labour needed to clear forest. [16]. Claims that that population growth drives

deforestation is weak and based on flawed data. [17] with population

increase due to high fertility rates being a primary driver of tropical

deforestation in only 8% of cases [18]. The FAO states that the global

deforestation rate is unrelated to human population growth rate, rather it is

the result of lack of technological advancement and inefficient governance[19]. There are many causes at the root of deforestation, such as the

corruption and inequitable distribution of wealth and power,[20][21][22]

population growth[23] and overpopulation,[24][25] and urbanization.[26]

Globalization is often viewed as a driver of deforestation.[27][28][29]


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According to British environmentalist Norman Myers, 5% of deforestation is

due to cattle ranching, 19% to over-heavy logging, 22% due to the growing

sector of palm oil plantations, and 54% due to slash-and-burn farming.[30]

Rates of deforestation

It's very difficult, if not impossible, to obtain figures for the rate of

deforestation [31] [32]. The FAO data are based largely on reporting from

forestry departments of individual countries. The World Bank estimates that

80% of logging operations are illegal in Bolivia and 42% in Colombia,[33]

while in Peru, illegal logging equals 80% of all activities.[34] For tropical

countries, deforestation estimates are very uncertain: based on satellite

imagery, the rate of deforestation in the tropics is 23% lower than the most

commonly quoted rates [35] and for the tropics as a whole deforestation

rates could be in error by as much as +/- 50% [36]. Conversely a new

analysis of satellite images reveal that the deforestation in the Amazon basinis twice as fast as scientists previously estimated.[37]

The UNFAO has the best long term datasets on deforestation available and

based on these datasets global forest cover has remained approximately

stable since the middle of the twentieth century [38]) and based on the

longest dataset available global forest cover has increased since 1954 [39].

The rate of deforestation is also declining, with less and less forest cleared

each decade. Globally the rate of deforestation declined during the 1980s,

[40] with even more rapid declines in the 1990s and still more rapid declines

from 2000 to 2005 [41]. Based on these trends global anti-deforestaionefforts is expected to outstrip deforestation within the next half-century with

global forest cover increasing by 10 percentan area the size of Indiaby

2050. Rates of deforestation are highest in developing tropical nations,

although globally the rate of tropical forest loss is also declining, with tropical

deforestation rates of about 8.6 million hectares annually in the 1990s,

compared to a loss of around 9.2 million hectares during the previous

decade. [42].

The utility of the FAO figures have been disputed by some environmental

groups. These questions are raised primarily because the figures do notdistinguish between forest types. The fear is that highly diverse habitats,

such as tropical rainforest, may be experiencing an increase in deforestation

which is being masked by large decreases in less biodiverse dry, open forest

types. Because of this omission it is possible that many of the negative

impacts of deforestation, such as habitat loss, are increasing despite a

decline in deforestation. Some environmentalists have predicted that unless


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significant[vague] measures such as seeking out and protecting old growth

forests that haven't been disturbed[43], are taken on a worldwide basis to

preserve them, by 2030 there will only be ten percent remaining [44][45]

with another ten percent in a degraded condition.[44] 80 percent will have

been lost and with them the irreversible loss of hundreds of thousands of

species.[44]

Despite the ongoing reduction in deforestation over the past 30 years the

process deforestation remains a serious global ecological problem and a

major social and economic problem in many regions. 13 million hectares of

forest are lost each year, 6 million hectares of which are forest that had been

largely undisturbed by human [46]. This results in a loss of habitat for wildlife

as well as reducing or removing the ecosystem services provided by these

forests.

The decline in the rate of deforestation also does not address the damagealready caused by deforestation. Global deforestation increased sharply in

the mid-1800s.[44] and about half of the mature tropical forests, between

7.5 million to 8 million square kilometres (2.9 million to 3 million sq mi) of

the original 15 million to 16 million square kilometres (5.8 million to 6.2

million sq mi) that until, 1947 [47][when?] covered the planet have been

cleared.[45]

The rate of deforestation also varies widely by region and despite a global

decline in some regions, particularly in developing tropical nations, the rate

of deforestation is increasing. For example, Nigeria lost 81% of its old-growth

forests[48] in just 15 years (1990- 2005). All of Africa is suffering

deforestation at twice the world rate.[49] The effects of deforestation are

most pronounced in tropical rainforests[50]. Brazil has lost 90-95% of its

Mata Atlntica forest.[51] In Central America, two-thirds of lowland tropical

forests have been turned into pasture since 1950.[52] Half of the Brazilian

state of Rondonia's 243,000 km have been affected by deforestation in

recent years[53] and tropical countries, including Mexico, India, Philippines,

Indonesia, Thailand, Myanmar, Malaysia, Bangladesh, China, Sri Lanka, Laos,Nigeria, Congo, Liberia, Guinea, Ghana and the Cte d'Ivoire have lost large

areas of their rainforest.[54][55] Because the rates vary so much across

regions the global decline in deforestation rates does not necessarily indicate

that the negative effects of deforestation are also declining.


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Large areas of Siberia have been harvested since the collapse of the Soviet

Union.[56] In the last two decades, Afghanistan has lost over 70% of its

forests throughout the country.[57]

Deforestation trends could follow the Kuznets curve[58] however even if true

this is problematic in so-called hot-spots because of the risk of irreversibleloss of non-economic forest values for example valuable habitat or species

loss.[59][60]

Environmental consequences

Impact on the physical environment

Atmospheric effects

Orbital photograph of human deforestation in progress in the Tierras Bajas

project in eastern Bolivia. Photograph courtesy NASA.

Deforestation is on going and is shaping climate and

geography.[61][62][63][64]

Deforestation is a contributor to global warming,[65][66] and is often cited as

one of the major causes of the enhanced greenhouse effect. Tropical

deforestation is responsible for approximately 20% of world greenhouse gas

emissions.[67] According to the Intergovernmental Panel on Climate Change

deforestation, mainly in tropical areas, account for up to one-third of total

anthropogenic carbon dioxide emissions.[68] Trees and other plants remove

carbon (in the form of carbon dioxide) from the atmosphere during theprocess of photosynthesis and release it back into the atmosphere during

normal respiration. Only when actively growing can a tree or forest remove

carbon over an annual or longer timeframe. Both the decay and burning of

wood releases much of this stored carbon back to the atmosphere. In order

for forests to take up carbon, the wood must be harvested and turned into

long-lived products and trees must be re-planted [69]. Deforestation may

cause carbon stores held in soil to be released. Forests are stores of carbon

and can be either sinks or sources depending upon environmental

circumstances. Mature forests alternate between being net sinks and net

sources of carbon dioxide (see Carbon dioxide sink and Carbon cycle.

Reducing emissions from the tropical deforestation and forest degradation

(REDD) in developing countries has emerged as new potential to

complement ongoing climate policies. The idea consists in providing financial

compensations for the reduction of greenhouse gas (GHG) emissions from

deforestation and forest degradation". [70]


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The worlds rain forests are widely believed by laymen to contribute a

significant amount of world's oxygen [71] although it is now accepted by

scientists that rainforests contribute little net oxygen to the atmosphere and

deforestation will have no effect whatsoever on atmospheric oxygen

levels.[72][73]. However, the incineration and burning of forest plants in

order to clear land releases tonnes of CO2 which contributes to global

warming.[66]

Forests are also able to extract carbon dioxide and pollutants from the air,

thus contributing to biosphere stability.

Hydrologic impacts

The water cycle is also affected by deforestation. Trees extract groundwater

through their roots and release it into the atmosphere. When part of a forest

is removed, the trees no longer evaporate away this water, resulting in a

much drier climate. Deforestation reduces the content of water in the soil

and groundwater as well as atmospheric moisture.[74] Deforestation reduces

soil cohesion, so that erosion, flooding and landslides ensue.[75][76] .

Forests enhance the recharge of aquifers in some locales however forests are

a major source of aquifer depletion on most locales [77].

Shrinking forest cover lessens the landscape's capacity to intercept, retain

and transpire precipitation[citation needed]. Instead of trapping

precipitation, which then percolates to groundwater systems, deforested

areas become sources of surface water runoff, which moves much faster

than subsurface flows[citation needed]. That quicker transport of surface

water can translate into flash flooding and more localized floods than would

occur with the forest cover. Deforestation also contributes to decreased

evapotranspiration, which lessens atmospheric moisture which in some cases

affects precipitation levels down wind from the deforested area, as water is

not recycled to downwind forests, but is lost in runoff and returns directly to

the oceans. According to one preliminary study[which?], in deforested north

and northwest China, the average annual precipitation decreased by one

third between the 1950s and the 1980s[vague] .

Trees, and plants in general, affect the water cycle significantly:

their canopies intercept a proportion of precipitation, which is then

evaporated back to the atmosphere (canopy interception);

their litter, stems and trunks slow down surface runoff;


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their roots create macropores - large conduits - in the soil that increase

infiltration of water;

they contribute to terrestrial evaporation and reduce soil moisture via

transpiration;

their litter and other organic residue change soil properties that affect the

capacity of soil to store water.

As a result, the presence or absence of trees can change the quantity of

water on the surface, in the soil or groundwater, or in the atmosphere. This

in turn changes erosion rates and the availability of water for either

ecosystem functions or human services.

The forest may have little impact on flooding in the case of large rainfall

events, which overwhelm the storage capacity of forest soil if the soils are at

or close to saturation.

Tropical rainforests produce about 30% of our planets fresh water.[78]

Soil erosion

Undisturbed forest has very low rates of soil loss, approximately 2 metric

tons per square kilometre (6 short tons per square mile).[citation needed]

Deforestation generally increases rates of soil erosion, by increasing the

amount of runoff and reducing the protection of the soil from tree litter. This

can be an advantage in excessively leached tropical rain forest soils. Forestry

operations themselves also increase erosion through the development ofroads and the use of mechanized equipment.

China's Loess Plateau was cleared of forest millennia ago. Since then it has

been eroding, creating dramatic incised valleys, and providing the sediment

that gives the Yellow River its yellow color and that causes the flooding of the

river in the lower reaches (hence the river's nickname 'China's sorrow').

Removal of trees does not always increase erosion rates. In certain regions of

southwest US, shrubs and trees have been encroaching on grassland. The

trees themselves enhance the loss of grass between tree canopies. The bare

intercanopy areas become highly erodible. The US Forest Service, in

Bandelier National Monument for example, is studying how to restore the

former ecosystem, and reduce erosion, by removing the trees.


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Tree roots bind soil together, and if the soil is sufficiently shallow they act to

keep the soil in place by also binding with underlying bedrock. Tree removal

on steep slopes with shallow soil thus increases the risk of landslides, which

can threaten people living nearby. However most deforestation only affects

the trunks of trees, allowing for the roots to stay rooted, negating the

landslide.

Ecological effects

Deforestation results in declines in biodiversity [79]. The removal or

destruction of areas of forest cover has resulted in a degraded environment

with reduced biodiversity.[80]. Forests support biodiversity, providing habitat

for wildlife;[81] moreover, forests foster medicinal conservation.[82]. With

forest biotopes being irreplaceable source of new drugs (like taxol),

deforestation can destroy genetic variations (such as crop resistance)

irretrievably.[83]

Since the tropical rainforests are the most diverse ecosystems on

earth[84][85] and about 80% of the world's known biodiversity could be

found in tropical rainforests[86][87] removal or destruction of significant

areas of forest cover has resulted in a degraded[88] environment with

reduced biodiversity[89]

Scientific understanding of the process of extinction is insufficient to

accurately to make predictions about the impact of deforestation on

biodiversity [90]. Most predictions of forestry related biodiversity loss are

based on species-area models, with an underlying assumption that as forest

are declines species diversity will decline similarly. [91]. However many such

models have been proven to be wrong and loss of habitat does not

necessarily lead to large scale loss of species[92]. Species-area models are

known to overpredict the number of species that known to be threatened in

areas where actual deforestation is ongoing, and greatly overpredict the

number of threatened species that are widespread [93].

Some experts[which?] estimate that we are losing 137 plant, animal and

insect species every single day due to rainforest deforestation, which

equates to 50,000 species a year.[94]. Others state that tropical rainforest

deforestation is contributing to the ongoing Holocene mass


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extinction.[95][96] The known extinction rates from deforestation rates are

very low, approximately 1 species per year from mammals and birds which

extrapolates to approximately 23000 species per year for all species.

Predictions have been made that more than 40% of the animal and plant

species in Southeast Asia could be wiped out in the 21st century.[97] with

such predictions called into questions by 1995 data that show that within

regions of Southeast Asia much of the original forest has been converted to

monospecific plantations but potentially endangered species are very low in

number and tree flora remains widespread and stable [98]

[edit]

Economic impact

Damage to forests and other aspects of nature could halve living standardsfor the world's poor and reduce global GDP by about 7% by 2050, a major

report has concluded at the Convention on Biological Diversity (CBD)

meeting in Bonn.[99] Historically utilization of forest products, including

timber and fuel wood, have played a key role in human societies, comparable

to the roles of water and cultivable land. Today, developed countries

continue to utilize timber for building houses, and wood pulp for paper. In

developing countries almost three billion people rely on wood for heating and

cooking.[100]

The forest products industry is a large part of the economy in both developed

and developing countries. Short-term economic gains made by conversion of

forest to agriculture, or over-exploitation of wood products, typically leads to

loss of long-term income and long term biological productivity (hence

reduction in nature's services). West Africa, Madagascar, Southeast Asia and

many other regions have experienced lower revenue because of declining

timber harvests. Illegal logging causes billions of dollars of losses to national

economies annually.[101]

The new procedures to get amounts of wood are causing more harm to the

economy and over powers the amount of money spent by people employed

in logging.[102] According to a study, "in most areas studied, the various

ventures that prompted deforestation rarely generated more than US$5 for

every ton of carbon they released and frequently returned far less than US


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$1." The price on the European market for an offset tied to a one-ton

reduction in carbon is 23 euro (about $35).[103]

[edit]

Historical causes

Further information: Timeline of environmental events

[edit]

Prehistory

Prehistory Deforestation has been practiced by humans for tens of thousands

of years before the beginnings of civilization[104]. Fire was the first tool that

allowed humans to modify the landscape. The first evidence of deforestation

appears in the Mesolithic period.[105] It was probably used to convert closed

forests into more open ecosystems favourable to game animals[106]. With

the advent of agriculture, fire became the prime tool to clear land for crops.

In Europe there is little solid evidence before 7000 BC. Mesolithic foragers

used fire to create openings for red deer and wild boar. In Great Britain shade

tolerant species such as oak and ash are replaced in the pollen record by

hazels, brambles, grasses and nettles. Removal of the forests led todecreased transpiration resulting in the formation of upland peat bogs.

Widespread decrease in elm pollen across Europe between 8400-8300 BC

and 7200-7000 BC, starting in southern Europe and gradually moving north

to Great Britain, may represent land clearing by fire at the onset of Neolithic

agriculture.

An array of Neolithic artifacts, including bracelets, axe heads, chisels, and

polishing tools.

The Neolithic period saw extensive deforestation for farming land.[107][108]

Stone axes were being made from about 3000 BC not just from flint, but from

a wide variety of hard rocks from across Britain and North America as well.

They include the noted Langdale axe industry in the English Lake District,

quarries developed at Penmaenmawr in North Wales and numerous other


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locations. Rough-outs were made locally near the quarries, and some were

polished locally to give a fine finish. This step not only increased the

mechanical strength of the axe, but also made penetration of wood easier.

Flint was still used from sources such as Grimes Graves but from many other

mines across Europe.

Evidence of deforestation has been found in Minoan Crete; for example the

environs of the Palace of Knossos were severely deforested in the Bronze

Age.[109]

[edit]

Pre-industrial history

Throughout most of history[when?], humans were hunter gatherers who

hunted within forests. In most areas, such as the Amazon, the Tropics,

Central America, and the Caribbean[110],only after shortages of wood and

other forest products are policies implemented to ensure forest resources are

used in a sustainable manner.

In ancient Greece, Tjeered van Andel and co-writers[111] summarized threeregional studies of historic erosion and alluviation and found that, wherever

adequate evidence exists, a major phase of erosion follows, by about 500-

1000 years the introduction of farming in the various regions of Greece,

ranging from the later Neolithic to the Early Bronze Age. The thousand years

following the mid-first millennium BCE saw serious, intermittent pulses of soil

erosion in numerous places. The historic silting of ports along the southern

coasts of Asia Minor (e.g. Clarus, and the examples of Ephesus, Priene and

Miletus, where harbors had to be abandoned because of the silt deposited by

the Meander) and in coastal Syria during the last centuries BC.

Easter Island has suffered from heavy soil erosion in recent centuries,

aggravated by agriculture and deforestation.[112] Jared Diamond gives an

extensive look into the collapse of the ancient Easter Islanders in his book


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Collapse. The disappearance of the island's trees seems to coincide with a

decline of its civilization around the 17th and 18th century.[113][114]

The famous silting up of the harbor for Bruges, which moved port commerce

to Antwerp, also follow a period of increased settlement growth (and

apparently[vague] of deforestation) in the upper river basins. In early

medieval Riez in upper Provence, alluvial silt from two small rivers raised the

riverbeds and widened the floodplain, which slowly buried the Roman

settlement in alluvium and gradually moved new construction to higher

ground; concurrently the headwater valleys above Riez were being opened to

pasturage.

A typical progress trap is that cities were often built in a forested areaproviding wood for some industry (e.g. construction, shipbuilding, pottery).

When deforestation occurs without proper replanting, local wood supplies

become difficult to obtain near enough to remain competitive, leading to the

city's abandonment, as happened repeatedly in Ancient Asia Minor. The

combination of mining and metallurgy often[vague] went along this self-

destructive path.

Meanwhile most of the population remaining active in (or indirectly

dependent on) the agricultural sector, the main pressure in most areas

remained land clearing for crop and cattle farming; fortunately enough wild

green was usually left standing (and partially used, e.g. to collect firewood,

timber and fruits, or to graze pigs) for wildlife to remain viable, and the

hunting privileges of the elite (nobility and higher clergy) often[when?]

protected significant[vague] woodlands.

Major parts in the spread (and thus more durable growth) of the population

were played by monastical 'pioneering' (especially by the Benedictine andCommercial orders) and some feudal lords actively attracting farmers to

settle (and become tax payers) by offering relatively good legal and fiscal

conditions even when they did so to launch or encourage cities, there

always was an agricultural belt around and even quite some within the walls.

When on the other hand demography took a real blow by such causes as the

Black Death or devastating warfare (e.g. Genghis Khan's Mongol hordes in


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eastern and central Europe, Thirty Years' War in Germany) this could lead to

settlements being abandoned, leaving land to be reclaimed by nature, even

though the secondary forests usually lacked the original biodiversity.

From 1100 to 1500 AD significant deforestation took place in Western Europe

as a result of the expanding human population. The large-scale building of

wooden sailing ships by European (coastal) naval owners since the 15th

century for exploration, colonisation, slave trade and other trade on the

high seas and (often related) naval warfare (the failed invasion of England by

the Spanish Armada in 1559 and the battle of Lepanto 1571 are early cases

of huge waste of prime timber; each of Nelson's Royal navy war ships at

Trafalgar had required 6000 mature oaks) and piracy meant that whole

woody regions were over-harvested, as in Spain, where this contributed to

the paradoxical weakening of the domestic economy since Columbus'discovery of America made the colonial activities (plundering, mining, cattle,

plantations, trade ...) predominant.

In Changes in the Land (1983), William Cronon collected 17th century New

England Englishmen's reports of increased seasonal flooding during the time

that the forests were initially cleared, and it was widely believed that it was

linked with widespread forest clearing upstream.

The massive[vague] use of charcoal on an industrial scale in Early Modern

Europe was a new acceleration of the onslaught on western forests; even in

Stuart England, the relatively primitive production of charcoal has already

reached an impressive level. For ship timbers, Stuart England was so widely

deforested that it depended on the Baltic trade and looked to the untapped

forests of New England to supply the need. In France, Colbert planted oak

forests to supply the French navy in the future; as it turned out, as the oak

plantations matured in the mid-nineteenth century, the masts were no longer

required.

Norman F. Cantor's summary of the effects of late medieval deforestation

applies equally well to Early Modern Europe:[115]


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"Europeans had lived in the midst of vast forests throughout the earlier

medieval centuries. After 1250 they became so skilled at deforestation that

by 1500 AD they were running short of wood for heating and cooking. They

were faced with a nutritional decline because of the elimination of the

generous supply of wild game that had inhabited the now-disappearing

forests, which throughout medieval times had provided the staple of their

carnivorous high-protein diet. By 1500 Europe was on the edge of a fuel and

nutritional disaster, [from] which it was saved in the sixteenth century only

by the burning of soft coal and the cultivation of potatoes and maize."

Specific parallels are seen in twentieth century deforestation occurring in

many developing nations.

[edit]

Deforestation today

Jungle burned for agriculture in southern Mexico.

[edit]

Rainforest deforestation

The difficulties of estimating deforestation rates are nowhere more apparent

than in the widely varying estimates of rates of rainforest deforestation. At

one extreme Alan Grainger, of Leeds University, argues that there is no

credible evidence of any longterm decline in rainforest area [116] while at

the other some environmental groups argue that one fifth of the world's

tropical rainforest was destroyed between 1960 and 1990, that rainforests 50

years ago covered 14% of the worlds land surface and have been reduced to6%.[117] and that all tropical forests will be gone by the year 2090 [118].

While the FAO states that the annual rate of tropical closed forest loss is

declining [119](FAO data are based largely on reporting from forestry

departments of individual countries)[120] from 8 million has in the 1980s to

7 million in the 1990s some environmentalists are stating that rainforest are

being destroyed at an ever-quickening pace.[121] The London-based


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Rainforest Foundation notes that "the UN figure is based on a definition of

forest as being an area with as little as 10% actual tree cover, which would

therefore include areas that are actually savannah-like ecosystems and badly

damaged forests."[122]

These divergent viewpoints are the result of the uncertainties in the extent of

tropical deforestation. For tropical countries, deforestation estimates are very

uncertain and could be in error by as much as +/- 50% [123] while based on

satellite imagery, the rate of deforestation in the tropics is 23% lower than

the most commonly quoted rates [124]. Conversely a new analysis of

satellite images reveal that deforestation of the Amazon rainforest is twice as

fast as scientists previously estimated.[125] The extent of deforestation that

has occurred in West Africa during the twentieth century is currently being

hugely exaggerated [126].

Despite these uncertainties there is agreement that development of

rainforests remains a significant environmental problem. Up to 90% of West

Africa's coastal rainforests have disappeared since 1900.[127] In South Asia,

about 88% of the rainforests have been lost.[128] Much of what of the

world's rainforests remains is in the Amazon basin, where the Amazon

Rainforest covers approximately 4 million square kilometres.[129] The

regions with the highest tropical deforestation rate between 2000 and 2005

were Central America -- which lost 1.3% of its forests each year -- and

tropical Asia.[130] In Central America, 40% of all the rainforests have been

lost in the last 40 years.[131] Madagascar has lost 90% of its eastern

rainforests.[132][133] As of 2007, less than 1% of Haiti's forests

remain.[134] Several countries,[135] notably the Brazil, have declared their

deforestation a national emergency.[136]

From about the mid-1800s, around 1852, the planet has experienced an

unprecedented[137] rate of change of destruction of forests worldwide.[44]More than half of the mature tropical forests that back in some thousand

years ago covered the planet have been cleared.[138]

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Africa

Africa is suffering deforestation at twice the world rate, according to the U.N.

Environment Programme (UNEP).[139][140] Some sources claim that

deforestation have already wiped out roughly 90% of the West Africa's

original forests.[141][142] Deforestation is accelerating in Central

Africa.[143] According to the FAO, Africa lost the highest percentage of

tropical forests of any continent.[144] According to the figures from the FAO

(1997), only 22.8% of West Africa's moist forests remain, much of this

degraded.[145] Massive deforestation threatens food security in some

African countries.[146]

Research carried out by WWF International [147] in 2002 shows that inAfrica, rates of illegal logging vary from 50% for Cameroon and Equatorial

Guinea to 70% in Gabon and 80% in Liberia where revenues from the

timber industry also fuelled the civil war.

[edit]

Ethiopia

Main article: Deforestation in Ethiopia

The main cause of deforestation in Ethiopia, located in East Africa, is a

growing population and subsequent higher demand for agriculture, livestock

production and fuel wood.[148] Other reasons include low education and

inactivity from the government,[149] although the current government has

taken some steps to tackle deforestation.[150] Organizations such as Farm

Africa are working with the federal and local governments to create a system

of forest management.[151] Ethiopia, the third largest country in Africa by

population, has been hit by famine many times because of shortages of rainand a depletion of natural resources. Deforestation has lowered the chance

of getting rain, which is already low, and thus causes erosion. Bercele Bayisa,

an Ethiopian farmer, offers one example why deforestation occurs. He said

that his district was forested and full of wildlife, but overpopulation caused

people to come to that land and clear it to plant crops, cutting all trees to sell

as fire wood.[152]


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Ethiopia has lost 98% of its forested regions in the last 50 years.[151] At the

beginning of the 20th century, around 420,000 km or 35% of Ethiopia's land

was covered with forests. Recent reports indicate that forests cover less than

14.2%[151] or even only 11.9% now.[153] Between 1990 and 2005, thecountry lost 14% of its forests or 21,000 km.

[edit]

Madagascar

Deforestation[154] with resulting desertification, water resource degradation

and soil loss has affected approximately 94% of Madagascar's previouslybiologically productive lands. Since the arrival of humans 2000 years ago,

Madagascar has lost more than 90% of its original forest.[155] Most of this

loss has occurred since independence from the French, and is the result of

local people using slash-and-burn agricultural practises as they try to

subsist.[156] Largely due to deforestation, the country is currently unable to

provide adequate food, fresh water and sanitation for its fast growing

population.[157][158]

[edit]

Nigeria

Main article: Deforestation in Nigeria

According to the FAO, Nigeria has the world's highest deforestation rate of

primary forests. It has lost more than half of its primary forest in the last five

years. Causes cited are logging, subsistence agriculture, and the collection of

fuel wood. Almost 90% of West Africa's rainforest has been destroyed.[159]

[edit]

Australia


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Victoria and NSW's remnant red gum forests including the Murray River's

Barmah-Millewa, are increasingly being clear-felled using mechanical

harvesters, destroying already rare habitat. Macnally estimates that

approximately 82% of fallen timber has been removed from the southern

Murray Darling basin,[160] and the Mid-Murray Forest Management Area

(including the Barmah and Gunbower forests) provides about 90% of

Victoria's red gum timber.[161]

One of the factors causing the loss of forest is expanding urban areas.

Littoral Rainforest growing along coastal areas of eastern Australia is now

rare due to ribbon development to accommodate the demand for seachange

lifestyles.[162]

[edit]

Brazil

Main article: Deforestation in Brazil

There is no agreement on what drives deforestation in Brazil, though a broad

consensus exists that expansion of croplands and pastures is important.

Increases in commodity prices may increase the rate of deforestation

[163][164] Recent development of a new variety of soybean has led to the

displacement of beef ranches and farms of other crops, which, in turn, move

farther into the forest.[165] Certain areas such as the Atlantic Rainforest

have been diminished to just 7% of their original size.[166] Although much

conservation work has been done, few national parks or reserves are

efficiently enforced.[167] Some 80% of logging in the Amazon is illegal.[168]

In 2008, Brazil's Government has announced a record rate of deforestation in

the Amazon.[169][170] Deforestation jumped by 69% in 2008 compared to2007's twelve months, according to official government data.[171]

Deforestation could wipe out or severely damage nearly 60% of the Amazon

rainforest by 2030, says a new report from WWF.[172]

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Canada

One case of deforestation in Canada is happening in Ontario's boreal forests,

near Thunder Bay, where 28.9% of a 19,000 km of forest area had been lost

in the last 5 years and is threatening woodland caribou. This is happening

mostly to supply pulp for the facial tissue industry[173].

In Canada, less than 8% of the boreal forest is protected from development

and more than 50% has been allocated to logging companies for

cutting.[174]

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Southeast Asia

The forest loss is acute in Southeast Asia,[175] the second of the world's

great biodiversity hot spots.[176] According to 2005 report conducted by the

FAO, Vietnam has the second highest rate of deforestation of primary forests

in the world second to only Nigeria.[177] More than 90% of the old-growth

rainforests of the Philippine archipelago have been cut.[178]

[edit]

Indonesia

At present rates, tropical rainforests in Indonesia would be logged out in 10

years, Papua New Guinea in 13 to 16 years.[179] There are significantly large

areas of forest in Indonesia that are being lost as native forest is cleared by

large multi-national pulp companies and being replaced by plantations. InSumatra tens of thousands of square kilometres of forest have been cleared

often[when?] under the command of the central government in Jakarta who

comply with multi national companies[180] to remove the forest because of

the need to pay off international debt obligations and to develop

economically[citation needed]. In Kalimantan, between 1991 and 1999 large

areas of the forest were burned because of uncontrollable fire causing


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atmospheric pollution across South-East Asia.[181] Every year, forest are

burned by farmers (slash-and-burn techniques are used by between 200 and

500 million people worldwide)[182] and plantation owners. A major source of

deforestation is the logging industry, driven spectacularly by China and

Japan.[183]. Agricultural development programs in Indonesia (transmigration

program) moved large populations into the rainforest zone, further increasing

deforestation rates.

A joint UK-Indonesian study of the timber industry in Indonesia in 1998

suggested that about 40% of throughout was illegal, with a value in excess of

$365 million.[184] More recent estimates, comparing legal harvesting

against known domestic consumption plus exports, suggest that 88% of

logging in the country is illegal in some way.[185] Malaysia is the key transit

country for illegal wood products from Indonesia.[186]

[edit]

United States

Loss of old growth forest in the United States.

1620, 1850, and 1920 maps: William B. Greeley, The Relation of Geography

to Timber Supply, Economic Geography, 1925, vol. 1, p. 1-11. Source of

TODAY map: compiled by George Draffan from roadless area map in The Big

Outside: A Descriptive Inventory of the Big Wilderness Areas of the United

States, by Dave Foreman and Howie Wolke (Harmony Books, 1992). These

maps represent only virgin forest lost. Some regrowth has occurred but not

to the age, size or extent of 1620 due to population increases and food

cultivation. See United States entry on left

Prior to the arrival of European-Americans about one half of the United Statesland area was forest, about 4 million square kilometers (1 billion acres) in

1600.[187] For the next 300 years land was cleared, mostly for agriculture at

a rate that matched the rate of population growth.[188] For every person

added to the population, one to two hectares of land was cultivated.[189]

This trend continued until the 1920s when the amount of crop land stabilized

in spite of continued population growth. As abandoned farm land reverted to


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forest the amount of forest land increased from 1952 reaching a peak in

1963 of 3,080,000 km (762 million acres). Since 1963 there has been a

steady decrease of forest area with the exception of some gains from 1997.

Gains in forest land have resulted from conversions from crop land and

pastures at a higher rate than loss of forest to development. Because urban

development is expected to continue, an estimated 93,000 km (23 million

acres) of forest land is projected be lost by 2050[190], a 3% reduction from

1997. Other qualitative issues have been identified such as the continued

loss of old-growth forest,[191] the increased fragmentation of forest lands,

and the increased urbanization of forest land.[192]

[edit]

Species extinctions in the Eastern Forest

According to a report by Stuart L. Pimm the extent of forest cover in the

Eastern United States reached its lowest point in roughly 1872 with about 48

percent compared to the amount of forest cover in 1620. Of the 28 forest

bird species with habitat exclusively in that forest, Pimm claims 4 become

extinct either wholly or mostly because of habitat loss, the passenger

pigeon, Carolina parakeet, ivory-billed woodpecker, and Bachman's

Warbler.[193]

[edit]

Controlling deforestation

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Farming

New methods are being developed to farm more intensively, such as high-

yield hybrid crops, greenhouse, autonomous building gardens, and

hydroponics. These methods are often dependent on massive[vague]

chemical inputs to maintain necessary yields. In cyclic agriculture, cattle are

grazed on farm land that is resting and rejuvenating. Cyclic agriculture

actually increases the fertility of the soil. Intensive farming can also decrease


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soil nutrients by consuming at an accelerated rate the trace minerals needed

for crop growth.[vague]

[edit]

Forest management

Efforts to stop or slow deforestation have been attempted for many centuries

because it has long been known that deforestation can cause environmental

damage sufficient in some cases to cause societies to collapse. In Tonga,

paramount rulers developed policies designed to prevent conflicts between

short-term gains from converting forest to farmland and long-term problems

forest loss would cause,[194] while during the seventeenth and eighteenth

centuries in Tokugawa Japan[195] the shoguns developed a highly

sophisticated system of long-term planning to stop and even reverse

deforestation of the preceding centuries through substituting timber by other

products and more efficient use of land that had been farmed for many

centuries. In sixteenth century Germany landowners also developed

silviculture to deal with the problem of deforestation. However, these policies

tend to be limited to environments with good rainfall, no dry season and very

young soils (through volcanism or glaciation). This is because on older and

less fertile soils trees grow too slowly for silviculture to be economic, whilst in

areas with a strong dry season there is always a risk of forest fires destroyinga tree crop before it matures.

In the areas where "slash-and-burn" is practiced, switching to "slash-and-

char" would prevent the rapid deforestation and subsequent degradation of

soils. The biochar thus created, given back to the soil, is not only a durable

carbon sequestration method, but it also is an extremely beneficial

amendment to the soil. Mixed with biomass it brings the creation of terra

preta, one of the richest soils on the planet and the only one known to

regenerate itself.

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Reforestation


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In many parts of the world, especially in East Asian countries, reforestation

and afforestation are increasing the area of forested lands [196]. The amount

of woodland has increased in 22 of the world's 50 most forested nations. Asia

as a whole gained 1 million hectares of forest between 2000 and 2005.Tropical forest in El Salvador expanded more than 20 percent between 1992

and 2001. Based on these trends global forest cover is expected to increase

by 10 percentan area the size of Indiaby 2050[197].

In the People's Republic of China, where large scale destruction of forests has

occurred, the government has in the past required that every able-bodied

citizen between the ages of 11 and 60 plant three to five trees per year or do

the equivalent amount of work in other forest services. The government

claims that at least 1 billion trees have been planted in China every year

since 1982. This is no longer required today, but March 12 of every year in

China is the Planting Holiday. Also, it has introduced the Green Wall of China-

project which aims to halt the expansion of the Gobi-desert through the

planting of trees. However, due to the large percentage of trees dying off

after planting (up to 75%), the project is not very successful[citation needed]

and regular carbon ofsetting through the Flexible Mechanisms might have

been a better option. There has been a 47-million-hectare increase in forest

area in China since the 1970s [198].

In western countries, increasing consumer demand for wood products that

have been produced and harvested in a sustainable manner are causing

forest landowners and forest industries to become increasingly accountable

for their forest management and timber harvesting practices.

The Arbor Day Foundation's Rain Forest Rescue program is a charity that

helps to prevent deforestation. The charity uses donated money to buy up

and preserve rainforest land before the lumber companies can buy it. The

Arbor Day Foundation then protects the land from deforestation. This also

locks in the way of life of the primitive tribes living on the forest land.

Organizations such as Community Forestry International, The Nature

Conservancy, World Wide Fund for Nature, Conservation International,

African Conservation Foundation and Greenpeace also focus on preserving


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forest habitats. Greenpeace in particular has also mapped out the forests

that are still intact and published this information unto the internet. [199].

HowStuffWorks in turn, made a more simple thematic map showing the

amount of forests present just before the age of man (8000 years ago) and

the current (reduced) levels of forest. This Greenpeace map thus created, as

well as this thematic map from howstuffworks marks the amount of

afforestation thus again required to repair the damage caused by man.

Definition of Deforestatio1

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