PHILIPPINE BIODIVERSITY

Deforestation
Deforestation, clearance or clearing is the removal of a forest or stand of trees where the land is thereafter converted to a non-forest use.[1] Examples of deforestation include conversion of forestland to farms, ranches, or urban use.
The term deforestation is often misused to describe any activity where all trees in an area are removed.[not in citation given][neutrality is disputed] However in temperate climates, the removal of all trees in an area[not in citation given]—in conformance with sustainable forestry practices—is correctly described as regeneration harvest.[2] In temperate mesic climates, natural regeneration of forest stands often will not occur in the absence of disturbance, whether natural or anthropogenic.[3] Furthermore, biodiversity after regeneration harvest often mimics that found after natural disturbance, including biodiversity loss after naturally occurring rainforest destruction.[4][5]
Deforestation occurs for many reasons: trees are cut down to be used or sold as fuel (sometimes in the form of charcoal) or timber, while cleared land is used as pasture for livestock, plantations of commodities and settlements. The removal of trees without sufficient reforestation has resulted in damage to habitat, biodiversity loss and aridity. It has adverse impacts on biosequestration of atmospheric carbon dioxide. Deforestation has also been used in war to deprive the enemy of cover for its forces and also vital resources. Modern examples of this were the use of Agent Orange by the British military in Malaya during the Malayan Emergency and the United States military in Vietnam during the Vietnam War. Among countries with a per capita GDP of at least US$4,600, net deforestation rates have ceased to increase.[when?][6][7] Deforested regions typically incur significant adverse soil erosion and frequently degrade into wasteland
Disregard or ignorance of intrinsic value, lack of ascribed value, lax forest management and deficient environmental laws are some of the factors that allow deforestation to occur on a large scale. In many countries, deforestation, both naturally occurring and human induced, is an ongoing issue. Deforestation causes extinction, changes to climatic conditions, desertification, and displacement of populations as observed by current conditions and in the past through the fossil record.[4] More than half of all plant and land animal species in the world live in tropical forests.[8]
Causes
According to the United Nations Framework Convention on Climate Change (UNFCCC) secretariat, the overwhelming direct cause of deforestation is agriculture. Subsistence farming is responsible for 48% of deforestation; commercial agriculture is responsible for 32% of deforestation; logging is responsible for 14% of deforestation and fuel wood removals make up 5% of deforestation.[9]
Experts do not agree on whether industrial logging is an important contributor to global deforestation.[10][11] 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.[10] One study found that population increases due to high fertility rates were a primary driver of tropical deforestation in only 8% of cases.[12]
Other causes of contemporary deforestation may include corruption of government institutions,[13][14] the inequitable distribution of wealth and power,[15] population growth[16] and overpopulation,[17][18] and urbanization.[19] Globalization is often viewed as another root cause of deforestation,[20][21] though there arecases in which the impacts of globalization (new flows of labor, capital, commodities, and ideas) have promoted localized forest recovery.[22]
The last batch of sawnwood from the peat forest in Indragiri Hulu, Sumatra, Indonesia. Deforestation for oil palm plantation.
In 2000 the United Nations Food and Agriculture Organization (FAO) found that "the role of population dynamics in a local setting may vary from decisive to negligible," and that deforestation can result from "a combination of population pressure and stagnating economic, social and technological conditions."[16]
The degradation of forest ecosystems has also been traced to economic incentives that make forest conversion appear more profitable than forest conservation.[23] Many important forest functions have no markets, and hence, no economic value that is readily apparent to the forests' owners or the communities that rely on forests for their well-being.[23] 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. 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.[24]
Some commentators have noted a shift in the drivers of deforestation over the past 30 years.[25] Whereas deforestation was primarily driven by subsistence activities and government-sponsored development projects like transmigration in countries like Indonesia and colonization in Latin America, India, Java, and so on, during late 19th century and the earlier half of the 20th century. By the 1990s the majority of deforestation was caused by industrial factors, including extractive industries, large-scale cattle ranching, and extensive agriculture.[26]
Environmental problems
AtmosphericDeforestation -is ongoing and is shaping climate and geography.[27][28][29][30][31]

Deforestation is a contributor to global warming,[32][33] 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.[34] According to the Intergovernmental Panel on Climate Change deforestation, mainly in tropical areas, could account for up to one-third of total anthropogenic carbon dioxide emissions.[35] But recent calculations suggest that carbon dioxide emissions from deforestation and forest degradation (excluding peatland emissions) contribute about 12% of total anthropogenic carbon dioxide emissions with a range from 6 to 17%.[36] Deforestation causes carbon dioxide to linger in the atmosphere. As carbon dioxide accrues, it produces a layer in the atmosphere that traps radiation from the sun. The radiation converts to heat which causes global warming, which is better known as the greenhouse effect.[37] Plants remove carbon in the form of carbon dioxide from the atmosphere during the process of photosynthesis, but release some carbon dioxide back into the atmosphere during normal respiration. Only when actively growing can a tree or forest remove carbon, by storing it in plant tissues. 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, there must be a net accumulation of wood. One way is for the wood to be harvested and turned into long-lived products, with new young trees replacing them.[38] Deforestation may also cause carbon stores held in soil to be released. Forests 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) However, the incineration and burning of forest plants to clear land releases large amounts of CO2, which contributes to global warming.[33] Scientists also state that tropical deforestation releases 1.5 billion tons of carbon each year into the atmosphere.[45]
Hydrological
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 transpire this water, resulting in a much drier climate. Deforestation reduces the content of water in the soil and groundwater as well as atmospheric moisture. The dry soil leads to lower water intake for the trees to extract.[46] Deforestation reduces soil cohesion,so that erosion, flooding and landslides ensue. 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 downwind 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 study, in deforested north and northwest China, the average annual precipitation decreased by one third between the 1950s and the 1980s.
Soil
Undisturbed forests have a very low rate of soil loss, approximately 2 metric tons per square kilometer (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. 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.
Biodiversity
Deforestation on a human scale results in decline in biodiversity,[50] and on a natural global scale is known to cause the extinction of many species.[4] The removal or destruction of areas of forest cover has resulted in a degraded environment with reduced biodiversity.[51] Forests support biodiversity, providing habitat for wildlife;[52] moreover, forests foster medicinal conservation.[53] With forest biotopes being irreplaceable source of new drugs (such as taxol), deforestation can destroy genetic variations (such as crop resistance) irretrievably.[54]
Illegal logging in Madagascar. In 2009, the vast majority of the illegally obtained rosewood was exported to China.

Since the tropical rainforests are the most diverse ecosystems on Earth[55][56] and about 80% of the world's known biodiversity could be found in tropical rainforests,[57][58] removal or destruction of significant areas of forest cover has resulted in a degraded[59] environment with reduced biodiversity.[4][60] A study in Rondônia, Brazil, has shown that deforestation also removes the microbial community which is involved in the recycling of nutrients, the production of clean water and the removal of pollutants.[61]

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.[62] Others state that tropical rainforest deforestation is contributing to the ongoing Holocene mass extinction.[63][64] The known extinction rates from deforestation rates are very low, approximately 1 species per year from mammals and birds which extrapolates to approximately 23,000 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.[65] Such predictions were called into question by 1995 data that show that within regions of Southeast Asia much of the original forest has been converted to monospecific plantations, but that potentially endangered species are few and tree flora remains widespread and stablRates of deforestation
Slash-and-burn farming in the state of Rondônia, western Brazil
Global deforestation[92] sharply accelerated around 1852.[93][94] It has been estimated that about half of the Earth's mature tropical forests—between 7.5 million and 8 million km2 (2.9 million to 3 million sq mi) of the original 15 million to 16 million km2 (5.8 million to 6.2 million sq mi) that until 1947 covered the planet[95]—have now been destroyed.[8][96] Some scientists have predicted that unless significant measures (such as seeking out and protecting old growth forests that have not been disturbed)[95] are taken on a worldwide basis, by 2030 there will only be 10% remaining,[93][96] with another 10% in a degraded condition.[93] 80% will have been lost, and with them hundreds of thousands of irreplaceable species.[93] Some cartographers have attempted to illustrate the sheer scale of deforestation by country using a cartogram.[97]

Estimates vary widely as to the extent of tropical deforestation.[98][99] Scientists estimate that one fifth of the world's tropical rainforest was destroyed between 1960 and 1990.[citation needed] They claim that that rainforests 50 years ago covered 14%[citation needed] of the world's land surface, now only cover 5–7%, and that all tropical forests will be gone by the middle of the 21st century.[100]
A 2002 analysis of satellite imagery suggested that the rate of deforestation in the humid tropics (approximately 5.8 million hectares per year) was roughly 23% lower than the most commonly quoted rates.[101] Conversely, a newer analysis of satellite images reveals that deforestation of the Amazon rainforest is twice as fast as scientists previously estimated.[102][103]
Some have argued that deforestation trends may follow a Kuznets curve,[104] which if true would nonetheless fail to eliminate the risk of irreversible loss of non-economic forest values (for example, the extinction of species).[105][106]
Satellite image of Haiti's border with the Dominican Republic (right) shows the amount of deforestation on the Haitian side
A 2005 report by the United Nations Food and Agriculture Organization (FAO) estimates that although the Earth's total forest area continues to decrease at about 13 million hectares per year, the global rate of deforestation has recently been slowing.[107][108] Still others claim that rainforests are being destroyed at an ever-quickening pace.[109] 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."[110] Other critics of the FAO data point out that they do not distinguish between forest types,[111] and that they are based largely on reporting from forestry departments of individual countries,[112] which do not take into account unofficial activities like illegal logging.[113]
Despite these uncertainties, there is agreement that destruction of rainforests remains a significant environmental problem. Up to 90% of West Africa's coastal rainforests have disappeared since 1900.[114] In South Asia, about 88% of the rainforests have been lost.[115] Much of what remains of the world's rainforests is in the Amazon basin, where the Amazon Rainforest covers approximately 4 million square kilometres.[116] 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.[110] In Central America, two-thirds of lowland tropical forests have been turned into pasture since 1950 and 40% of all the rainforests have been lost in the last 40 years.[117] Brazil has lost 90–95% of its Mata Atlântica forest.,[118] Paraguay was losing its natural semi humid forests in the country’s western regions at a rate of 15.000 hectares at a randomly studied 2-month period in 2010,[119] Paraguay’s parliament refused in 2009 to pass a law that would have stopped cutting of natural forests altogether.[120]
Deforestation around Pakke Tiger Reserve, India
Madagascar has lost 90% of its eastern rainforests.[121][122] As of 2007, less than 1% of Haiti's forests remained.[123] Mexico, India, the Philippines, Indonesia, Thailand, Burma, Malaysia, Bangladesh, China, Sri Lanka, Laos, Nigeria, the Democratic Republic of the Congo, Liberia, Guinea, Ghana and the Ivory Coast, have lost large areas of their rainforest.[124][125] Several countries, notably Brazil, have declared their deforestation a national emergency.[126][127] The World Wildlife Fund's ecoregion project catalogues habitat types throughout the world, including habitat loss such as deforestation, showing for example that even in the rich forests of parts of Canada such as the Mid-Continental Canadian forests of the prairie provinces half of the forest cover has been lost or altered.e
Reducing emissions /solutions:
Main article: Reducing emissions from deforestation and forest degradation
Main international organizations including the United Nations and the World Bank, have begun to develop programs aimed at curbing deforestation. The blanket term Reducing Emissions from Deforestation and Forest Degradation (REDD) describes these sorts of programs, which use direct monetary or other incentives to encourage developing countries to limit and/or roll back deforestation. Funding has been an issue, but at the UN Framework Convention on Climate Change (UNFCCC) Conference of the Parties-15 (COP-15) in Copenhagen in December 2009, an accord was reached with a collective commitment by developed countries for new and additional resources, including forestry and investments through international institutions, that will approach USD 30 billion for the period 2010–2012.[139] Significant work is underway on tools for use in monitoring developing country adherence to their agreed REDD targets. These tools, which rely on remote forest monitoring using satellite imagery and other data sources, include the Center for Global Development's FORMA (Forest Monitoring for Action) initiative [140] and the Group on Earth Observations' Forest Carbon Tracking Portal.[141] Methodological guidance for forest monitoring was also emphasized at COP-15.[142] The environmental organization Avoided Deforestation Partners leads the campaign for development of REDD through funding from the U.S. government.[
Monitoring deforestation-One method is the “visual interpretation of aerial photos or satellite imagery that is labor-intensive but does not require high-level training in computer image processing or extensive computational resourcesAnother method includes hot-spot analysis (that is, locations of rapid change) using expert opinion or coarse resolution satellite data to identify locations for detailed digital analysis with high resolution satellite images.[76] Deforestation is typically assessed by quantifying the amount of area deforested, measured at the present time. From an environmental point of view, quantifying the damage and its possible consequences is a more important task, while conservation efforts are more focused on forested land protection and development of land-use alternatives to avoid continued deforestation.[”
Sustainable practices
Programme for the Endorsement of Forest Certification and Forest Stewardship Council, contributes to tackling deforestation by creating market demand for timber from sustainably managed forests. According to the United Nations Food and Agriculture Organization (FAO), "A major condition for the adoption of sustainable forest management is a demand for products that are produced sustainably and consumer willingness to pay for the higher costs entailed
Rainforest Rescue argues that the standards of organizations like FSC are too closely connected to industry interests and therefore do not guarantee environmentally and socially responsible forest management. In reality, monitoring systems are inadequate and various cases of fraud have been documented worldwide.
*Reforestation
*Forest plantations
*Forest management
*Farming