Deforestation

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Deforestation is the logging or burning of trees in forested areas. There are several reasons for doing so: trees or derived charcoal can be sold as a commodity and are used by humans while cleared land is used as pasture, plantations of commodities and human settlement. The removal of trees without sufficient reforestation, has resulted in damage to habitat, biodiversity loss and aridity. Also deforested regions often degrade into wasteland.

Disregard or unawareness of intrinsic value, and lack of ascribed value, lax forest management and environmental law allow deforestation to occur on such a large scale. In many countries, deforestation is an ongoing issue which is causing extinction, changes to climatic conditions, desertification and displacement of indigenous people.

[edit] Causes of anthropogenic deforestation

In simple terms, deforestation occurs because forested land is not economically viable. Increasing the amount of farmland, woods are used by native populations of over 200 million people worldwide.

The presumed value of forests as a genetic resources has never been confirmed by any economic studies ^[1]. As a result owners of forested land lose money by not clearing the forest and this affects the welfare of the whole society ^[2]. 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 shouldn’t have to bear the cost of preservation when the rich created the problem ^[3].

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 ^[4] and some believe that logging makes considerable contribution to reducing deforestation because in developing countries logging reserves are far larger than nature reserves ^[5]. 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. ^[6]. Claims that that population growth drives deforestation is weak and based on flawed data. ^[7] with population increase due to high fertility rates being a primary driver of tropical deforestation in only 8% of cases ^[8]. 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 ^[9]. There are many causes at the root of deforestation, such as the corruption and inequitable distribution of wealth and power,^[10][11][12] population growth^[13] and overpopulation,^[14][15] and urbanization.^[16] Globalization is often viewed as a driver of deforestation.^[17][18][19]

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.^[20]

[edit] Rates of deforestation

Deforestation in Mato Grosso, Brazil, 1992

Deforestation in Mato Grosso, Brazil, 2006

It's very difficult, if not impossible, to obtain figures for the rate of deforestation ^{[21] [22]}. 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,^[23] while in Peru, illegal logging equals 80% of all activities.^[24] 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 ^[25] and for the tropics as a whole deforestation rates could be in error by as much as +/- 50% ^[26]. Conversely a new analysis of satellite images reveal that the deforestation in the Amazon basin is twice as fast as scientists previously estimated.^[27]

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 ^[28]) and based on the longest dataset available global forest cover has increased since 1954 ^[29]. The rate of deforestation is also declining, with less and less forest cleared each decade. Globally the rate of deforestation declined during the 1980s, ^[30] with even more rapid declines in the 1990s and still more rapid declines from 2000 to 2005 ^[31]. Based on these trends global anti-deforestation efforts are expected to outstrip deforestation within the next half-century with global forest cover increasing by 10 percent—an area the size of India—by 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. ^[32].

The utility of the FAO figures have been disputed by some environmental groups. These questions are raised primarily because the figures do not distinguish 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 significant^[vague] measures such as seeking out and protecting old growth forests that haven't been disturbed^[33], are taken on a worldwide basis to preserve them, by 2030 there will only be ten percent remaining ^[34][35] with another ten percent in a degraded condition.^[34] 80 percent will have been lost and with them the irreversible loss of hundreds of thousands of species.^[34]

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 man ^[36]. 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 damage already caused by deforestation. Global deforestation increased sharply in the mid-1800s.^[34] 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 ^[37][when?] covered the planet have been cleared.^[35]

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^[38] in just 15 years (1990- 2005). All of Africa is suffering deforestation at twice the world rate.^[39] The effects of deforestation are most pronounced in tropical rainforests^[40]. Brazil has lost 90-95% of its Mata Atlântica forest.^[41] In Central America, two-thirds of lowland tropical forests have been turned into pasture since 1950.^[42] Half of the Brazilian state of Rondonia's 243,000 km² have been affected by deforestation in recent years^[43] and tropical countries, including Mexico, India, Philippines, Indonesia, Thailand, Myanmar, Malaysia, Bangladesh, China, Sri Lanka, Laos, Nigeria, Congo, Liberia, Guinea, Ghana and the Côte d'Ivoire have lost large areas of their rainforest.^[44][45] 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.

Large areas of Siberia have been harvested since the collapse of the Soviet Union.^[46] In the last two decades, Afghanistan has lost over 70% of its forests throughout the country.^[47]

Deforestation trends could follow the Kuznets curve^[48] however even if true this is problematic in so-called hot-spots because of the risk of irreversible loss of non-economic forest values for example valuable habitat or species loss.^[49][50]

[edit] Environmental factors and impacts

[edit] Atmospheric

Orbital photograph of human deforestation in progress in the Tierras Bajas project in eastern Bolivia. Photograph courtesy NASA.

Deforestation is ongoing and is shaping climate and geography.^{[51][52][53][54]}

Deforestation is a contributor to global warming,^[55][56] 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.^[57] 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.^[58] Trees and other plants remove carbon (in the form of carbon dioxide) from the atmosphere during the process 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.^[59] 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". ^[60]

The worlds rain forests are widely believed by laymen to contribute a significant amount of world's oxygen ^[61] 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.^[62][63] However, the incineration and burning of forest plants in order to clear land releases tonnes of CO₂ which contributes to global warming.^[56]

Forests are also able to extract carbon dioxide and pollutants from the air, thus contributing to biosphere stability.

[edit] Hydrologic

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.^[64] Deforestation reduces soil cohesion, so that erosion, flooding and landslides ensue.^[65][66] Forests enhance the recharge of aquifers in some locales, however, forests are a major source of aquifer depletion on most locales.^[67]

Shrinking forest cover lessens the landscape's capacity to intercept, retain and transpire precipitation. 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. 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, in deforested north and northwest China, the average annual precipitation decreased by one third between the 1950s and the 1980s.^{[citation needed]}

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;
• 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.
• their leaves control the humidity of the atmosphere by traspiration. 99% of the water pulled up by the roots move up to the leaves for transpiration.^[68]

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.^[69]

[edit] Soil

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 of roads 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.

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.

[edit] Ecological

Deforestation results in declines in biodiversity.^[70] The removal or destruction of areas of forest cover has resulted in a degraded environment with reduced biodiversity.^[71] Forests support biodiversity, providing habitat for wildlife;^[72] moreover, forests foster medicinal conservation.^[73] With forest biotopes being irreplaceable source of new drugs (such as taxol), deforestation can destroy genetic variations (such as crop resistance) irretrievably.^[74]

Since the tropical rainforests are the most diverse ecosystems on earth^[75][76] and about 80% of the world's known biodiversity could be found in tropical rainforests^[77][78] removal or destruction of significant areas of forest cover has resulted in a degraded^[79] environment with reduced biodiversity.^[80]

Scientific understanding of the process of extinction is insufficient to accurately make predictions about the impact of deforestation on biodiversity.^[81] 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.^[82] However, many such models have been proven to be wrong and loss of habitat does not necessarily lead to large scale loss of species.^[83] Species-area models are known to overpredict the number of species known to be threatened in areas where actual deforestation is ongoing, and greatly overpredict the number of threatened species that are widespread.^[84]

It has been estimated 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.^[85] Others state that tropical rainforest deforestation is contributing to the ongoing Holocene mass extinction.^[86][87] 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,^[88] 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.^[89]

[edit] Economic impact

Damage to forests and other aspects of nature could halve living standards for the world's poor and reduce global GDP by about 7% by 2050, a major report concluded at the Convention on Biological Diversity (CBD) meeting in Bonn.^[90] 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.^[91]

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.^[92]

The new procedures to get amounts of wood are causing more harm to the economy and overpowers the amount of money spent by people employed in logging.^[93] 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 $1." The price on the European market for an offset tied to a one-ton reduction in carbon is 23 euro (about $35).^[94]

[edit] Historical causes

[edit] Prehistory

Deforestation has been practiced by humans for tens of thousands of years before the beginnings of civilization.^[95] Fire was the first tool that allowed humans to modify the landscape. The first evidence of deforestation appears in the Mesolithic period.^[96] It was probably used to convert closed forests into more open ecosystems favourable to game animals.^[97] 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 to decreased 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.^[98][99] 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 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.^[100]

[edit] Pre-industrial history

Throughout most of history, humans were hunter gatherers who hunted within forests. In most areas, such as the Amazon, the tropics, Central America, and the Caribbean,^[101] only after shortages of wood and other forest products occur are policies implemented to ensure forest resources are used in a sustainable manner.

In ancient Greece, Tjeered van Andel and co-writers^[102] summarized three regional studies of historic erosion and alluviation and found that, wherever adequate evidence exists, a major phase of erosion follows, by about 500-1,000 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.^[103] Jared Diamond gives an extensive look into the collapse of the ancient Easter Islanders in his book Collapse. The disappearance of the island's trees seems to coincide with a decline of its civilization around the 17th and 18th century.^[104][105]

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 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.^{[citation needed]}

A typical progress trap is that cities were often built in a forested area providing 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 went along this self-destructive path.^{[citation needed]}

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 protected significant woodlands.^{[citation needed]}

Major parts in the spread (and thus more durable growth) of the population were played by monastical 'pioneering' (especially by the Benedictine and Commercial 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 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 6,000 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 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:^[106]

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 ^[107] 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 to 6%.^[85] and that all tropical forests will be gone by the year 2090 ^[85]. While the FAO states that the annual rate of tropical closed forest loss is declining ^[108](FAO data are based largely on reporting from forestry departments of individual countries)^[109] 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.^[110] The London-based 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."^[111]

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% ^[112] while based on satellite imagery, the rate of deforestation in the tropics is 23% lower than the most commonly quoted rates ^[113]. Conversely a new analysis of satellite images reveal that deforestation of the Amazon rainforest is twice as fast as scientists previously estimated.^[114] The extent of deforestation that has occurred in West Africa during the twentieth century is currently being hugely exaggerated ^[115].

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.^[116] In South Asia, about 88% of the rainforests have been lost.^[117] Much of what of the world's rainforests remains is in the Amazon basin, where the Amazon Rainforest covers approximately 4 million square kilometres.^[118] 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.^[111] In Central America, 40% of all the rainforests have been lost in the last 40 years.^[42] Madagascar has lost 90% of its eastern rainforests.^[119][120] As of 2007, less than 1% of Haiti's forests remain.^[121] Several countries,^[122] notably Brazil, have declared their deforestation a national emergency.^[123]

From about the mid-1800s, around 1852, the planet has experienced an unprecedented^[124] rate of change of destruction of forests worldwide.^[34] More than half of the mature tropical forests that back in some thousand years ago covered the planet have been cleared.^[125]

A January 30, 2009 New York Times article stated, "By one estimate, for every acre of rain forest cut down each year, more than 50 acres of new forest are growing in the tropics..." The new forest includes secondary forest on former farmland and so-called degraded forest.^[126]

[edit] Africa

Africa is suffering deforestation at twice the world rate, according to the U.N. Environment Programme (UNEP).^[127][128] Some sources claim that deforestation have already wiped out roughly 90% of the West Africa's original forests.^[129][130] Deforestation is accelerating in Central Africa.^[131] According to the FAO, Africa lost the highest percentage of tropical forests of any continent.^[132] According to the figures from the FAO (1997), only 22.8% of West Africa's moist forests remain, much of this degraded.^[133] Massive deforestation threatens food security in some African countries.^[52] Africa experiences one of the highest rates of deforestation due to 90% of its population being dependent on wood for wood-fuel energy as the main source of heating and cooking. ^[134].

Research carried out by WWF International ^[135] in 2002 shows that in Africa, 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

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.^[136] Other reasons include low education and inactivity from the government,^[137] although the current government has taken some steps to tackle deforestation.^[138] Organizations such as Farm Africa are working with the federal and local governments to create a system of forest management.^[139] Ethiopia, the third largest country in Africa by population, has been hit by famine many times because of shortages of rain and 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.^[140]

Ethiopia has lost 98% of its forested regions in the last 50 years.^[139] At the beginning of the 20th century, around 420,000 km² or 35% of Ethiopia's land was covered with forests. Recent reports indicate that forests cover less than 14.2%^[139] or even only 11.9% now.^[141] Between 1990 and 2005, the country lost 14% of its forests or 21,000 km².

[edit] Madagascar

Deforestation^[142] with resulting desertification, water resource degradation and soil loss has affected approximately 94% of Madagascar's previously biologically productive lands. Since the arrival of humans 2000 years ago, Madagascar has lost more than 90% of its original forest.^[143] 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.^[144] Largely due to deforestation, the country is currently unable to provide adequate food, fresh water and sanitation for its fast growing population.^[145][146]

[edit] 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.^[147]

[edit] Iceland

Iceland has undergone extensive deforestation since Vikings settled in the ninth century. As a result, vast areas of vegetation and land has degraded, and soil erosion and desertification has occurred. As much as half of the original vegetative cover has been destroyed, caused in part by overexploitation, logging and overgrazing under harsh natural conditions. About 95% of the forests and woodlands once covering at least 25% of the area of Iceland may have been lost. Afforestation and revegetation has restored small areas of land.^[148]

[edit] Australia

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,^[149] and the Mid-Murray Forest Management Area (including the Barmah and Gunbower forests) provides about 90% of Victoria's red gum timber.^[150]

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.^[151]

[edit] 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 ^[152][153] 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.^[154] Certain areas such as the Atlantic Rainforest have been diminished to just 7% of their original size.^[155] Although much conservation work has been done, few national parks or reserves are efficiently enforced.^[156] Some 80% of logging in the Amazon is illegal.^[157]

In 2008, Brazil's Government has announced a record rate of deforestation in the Amazon.^[158][159] Deforestation jumped by 69% in 2008 compared to 2007's twelve months, according to official government data.^[160] Deforestation could wipe out or severely damage nearly 60% of the Amazon rainforest by 2030, says a new report from WWF.^[161]

[edit] Canada

One case of deforestation in Canada is happening in Ontario's boreal forests, near Thunder Bay, where 28.9% of a 19,000 km² 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^[162].

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.^[163]

[edit] Southeast Asia

The forest loss is acute in Southeast Asia,^[164] the second of the world's great biodiversity hot spots.^[165] 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.^[166] More than 90% of the old-growth rainforests of the Philippine archipelago have been cut.^[167]

[edit] Russia

Russia has the largest area of forests of any nation on Earth. ^[168] There is little recent research into the rates of deforestation but in 1992 2 million hectares of forest was lost and in 1994 around 3 million hectares were lost. ^[169]. The present scale of deforestation in Russia is most easily seen using Google Earth, areas nearer to China are most affected as it is the main market for the timber. ^[170]. Deforestation in Russia is particularly damaging as the forests have a short growing season due to extremely cold winters and therefore will take longer to recover.

[edit] Indonesia

At present rates, tropical rainforests in Indonesia would be logged out in 10 years, Papua New Guinea in 13 to 16 years.^[171] 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. In Sumatra 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^[172] 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 atmospheric pollution across South-East Asia.^[173] Every year, forest are burned by farmers (slash-and-burn techniques are used by between 200 and 500 million people worldwide)^[174] and plantation owners. A major source of deforestation is the logging industry, driven spectacularly by China and Japan.^[175]. 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.^[176] 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.^[177] Malaysia is the key transit country for illegal wood products from Indonesia.^[178]

[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 States land area was forest, about 4 million square kilometers (1 billion acres) in 1600.^[179] For the next 300 years land was cleared, mostly for agriculture at a rate that matched the rate of population growth.^[180] For every person added to the population, one to two hectares of land was cultivated.^[181] 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 forest the amount of forest land increased from 1952 reaching a peak in 1963 of 3,080,000 km² (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 km² (23 million acres) of forest land is projected be lost by 2050^[182], a 3% reduction from 1997. Other qualitative issues have been identified such as the continued loss of old-growth forest,^[183] the increased fragmentation of forest lands, and the increased urbanization of forest land.^[184]

[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.^[185]

[edit] Controlling deforestation

[edit] Kyoto Protocol

A key factor in controlling deforestation could come from the Kyoto Protocol. Avoided deforestation also known as Reduced Emissions from Deforestation and Degradation (REDD) could be implemented in a future Kyoto Protocol and allow the protection of a great amount of forests. ^[186] At the moment, REDD is not yet implemented into any of the flexible mechanisms as CDM, JI or ET.

[edit] 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 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 soil nutrients by consuming at an accelerated rate the trace minerals needed for crop growth.^{[citation needed]}

[edit] Effect of deforestation

Deforestation presents multiple societal and environmental problems. The immediate and long-term consequences of global deforestation are almost certain to jeopardize life on Earth, as we know it. Some of these consequences include: loss of biodiversity; the destruction of forest-based-societies; and climatic disruption. For example, much loss of the Amazon Rainforest can cause enormous amounts of carbon dioxide to be released back into the atmosphere.^[187]

[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,^[188] while during the seventeenth and eighteenth centuries in Tokugawa Japan^[189] 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 destroying a 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.

[edit] Reforestation

In many parts of the world, especially in East Asian countries, reforestation and afforestation are increasing the area of forested lands ^[190]. 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 percent—an area the size of India—by 2050^[191].

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 ^[192]. The total number of trees amounted to be about 35 billion and 4.55% of China's land mass increased in forest coverage. The forest coverage was 12% two decades ago and now is 16.55%.^[193].

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 forest habitats. Greenpeace in particular has also mapped out the forests that are still intact and published this information unto the internet. ^[194]. 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.

[edit] Forest plantations

To meet the worlds demand for wood it has been suggested by forestry writers Botkins and Sedjo that high-yielding forest plantations are suitable. It has been calculated that plantations yielding 10 cubic meters per hectare annually could supply all the timber required for international trade on 5 percent of the world's existing forestland. By contrast natural forests produce about 1-2 cubic meters per hectare, therefore 5 to 10 times more forest land would be required to meet demand. Forester Chad Oliver has suggested a forest mosaic with high-yield forest lands interpersed with conservation land.^[195]

According to an international team of scientists, led by Pekka Kauppi, professor of environmental science and policy at Helsinki University, the deforestation already done could still be reverted by tree plantings (eg CDM & JI afforestation/reforestation projects) in 30 years. The conclusion was made, through analysis of data acquired from FAO. ^[196]

Reforestation through tree planting (trough eg the noted CDM & JI A/R-projects), might take advantage of the changing precipitation due to climate change. This may be done through studying where the precipitation is perceived to be increased (see the globalis thematic map of the 2050 precipitation) and setting up reforestation projects in these locations. Especially areas such as Niger, Sierra Leone and Liberia are important candidates; in huge part because they also suffer from an expanding desert (the Sahara) and decreasing biodiversity (while being an important biodiversity hotspot).

[edit] Military context

American Sherman tanks knocked out by Japanese artillery on Okinawa.

While the preponderance of deforestation is due to demands for agricultural and urban use for the human population, there are some examples of military causes. One example of deliberate deforestation is that which took place in the U.S. zone of occupation in Germany after World War II. Before the onset of the Cold War defeated Germany was still considered a potential future threat rather than potential future ally. To address this threat, attempts were made to lower German industrial potential, of which forests were deemed an element. Sources in the U.S. government admitted that the purpose of this was the "ultimate destruction of the war potential of German forests." As a consequence of the practice of clear-felling, deforestation resulted which could "be replaced only by long forestry development over perhaps a century."^[197]

War can also be a cause of deforestation, either deliberately such as through the use of Agent Orange^[198] during the Vietnam War where, together with bombs and bulldozers, it contributed to the destruction of 44 percent of the forest cover,^[199] or inadvertently such as in the 1945 Battle of Okinawa where bombardment and other combat operations reduced the lush tropical landscape into "a vast field of mud, lead, decay and maggots".^[200]

[edit] See also

[edit] References

[edit] Notes

[edit] General references

[edit] Ethiopia deforestation references

[edit] External links

Wikimedia Commons has media related to: Deforestation

• Encyclopedia of Earth: Deforestation in Amazonia
• Global Forest Resources Assessment 2005 by the FAO Comprehensive assessment of forests and forestry. Includes 350 page report and 15 page summary
• United Nations EarthWatch
• EU Forestry.
• United Nations Forum on Forests
• CFAN - CIDA Forestry Advisory Network DEFORESTATION: Tropical Forests in Decline
• Amazon Deforestation (Google maps)
• Our disappearing forests - Greenpeace China
• Cocaine destroys 4 m2 of rainforest per gram The Guardian
• “Avoided Deforestation” Plan Gains Support - Worldwatch Institute

[edit] In the media

• March 14, 2007, Independent Online: Destruction of forests in developing world 'out of control'

[edit] Films online

• Watch the National Film Board of Canada documentaries Battle for the Trees & Forest in Crisis