Deforestation
Deforestation or deforestation is a process caused by human action, in which the forest area is destroyed or depleted, generally with the purpose of allocating the land to another activity. At present, it is directly related to industrial activities, such as slash and burn for the expansion of the agricultural frontier to give rise to intensive agriculture and livestock. The expansion of urban areas and mining activities also drive deforestation. The construction of roads and access roads to increasingly remote forests through poaching contributes to deforestation. To a lesser extent, subsistence farming is also involved in deforestation activities. According to British researcher Norman Myers, 5% of deforestation is due to cattle ranching, 19% to excessive logging, 22% to tree plantations (mostly to palm oil) and 54% to slash-and-burn agriculture.
Deforestation has a direct impact on current climate change and global warming. Deforestation and other agricultural practices are estimated to have contributed around 20% of global carbon dioxide emissions in past decades. Deforestation destroys soil quality, contributing to soil erosion and desertification, increasing the release of mineral dust and thus contributing to sandstorms. Forest ecosystems act as carbon sinks and play a crucial role in absorbing greenhouse gases, so deforestation has an adverse impact on the fixation of carbon dioxide (CO2).
More than 70% of animals and plants live in forest areas, so deforestation has a dramatic impact on habitat loss for millions of species, species extinction, declining insect populations, loss of global biomass and biodiversity. Deforestation affects the albedo of the earth, producing changes in global temperatures, winds, and precipitation. Trees also contribute to the hydrological cycle by returning water vapor to the atmosphere. The removal of trees also causes extreme temperature fluctuations.
Deforestation causes the displacement of indigenous populations and rural communities, and increases the spread and varieties of infectious diseases transmitted to humans by animals that lose their habitat.
Since 1750, the largest changes in the planet's surface have been produced by deforestation in temperate climates: when forests and jungles are reduced to make room for grass, the albedo of the affected region increases, which could produce warming or cooling, depending on local conditions. Deforestation also affects carbon sequestration, which can lead to elevated concentrations of CO2, the main component of greenhouse gases. Certain modes of land clearing such as Slash and burn worsen these effects by burning biomass, which directly releases greenhouse gases and particles such as soot into the air.
Forests still cover about 31% of the world's regions. 10,000 years ago, before the expansion of agriculture, the planet's forest cover was about 50%. Most of this loss of forest area has occurred in the last century. Brazil, Indonesia, Myanmar, Nigeria and Tanzania are the five countries that had the highest percentage of deforestation in the period 2010-2015. Sustainable Development number 15 calls to stop deforestation by 2020.
Definition
There are disagreements about the definition of the term deforestation. The current positions can be divided into two: those who define deforestation in a broad sense, and those who define deforestation in a narrow sense.
Deforestation in a narrow sense refers exclusively to the removal or total extraction of vegetation cover in order to allocate the land to another use. The FAO has chosen to define deforestation as "forest change with depletion of tree crown cover to less than 10 percent", that is, 90% of the forest and of the trees must be destroyed to be considered deforestation. All remaining processes that somehow impact the forest are considered as "degradation", and not as deforestation. This perspective is mostly favored by geographers, economists, and land use planners.
The broad definition includes not only the removal or total extraction of vegetation cover to allocate the land to another use, but also other types of degradation that reduce the quality of forests (for example, the loss of biodiversity in forest, density and structure, biomass, among others). British researcher Norman Myers defines this type of process as "degradation so severe that the residual forest cannot be classified as forest in any practical sense of the word". This definition is mostly used by conservationists, biologists and environmentalists.
The type of definition adopted has an impact on the production of deforestation data. Thus, depending on whether one criterion or the other is adopted, the deforestation rate will vary in relation to the definition used.
In the Spanish language the term "desmonte" to refer to deforestation, especially in certain geographic areas such as Argentina. The term clearing, however, refers to the process of "cutting trees or bushes in a forest or part of it", probably alluding to the existing vegetation in forest ecosystems. Although used interchangeably with "deforestation" and "degradation", the term does not have a precise scientific definition.
Theoretical perspectives
Three theoretical approaches to deforestation can be distinguished: the poverty school, the neoclassical school and the political ecology school. These three schools differ in their identification of the causes and agents, but above all in the responses or actions needed to stop deforestation. According to Sven Wunder, "different attitudes and explanations can coexist in the same country or region. Some features may also be combined under certain circumstances. [...] In other respects, however, the focus and political predictions of the different approaches on how to stop deforestation are incompatible".
School of poverty
For the school of poverty, the main cause of deforestation is the increasing number of poor people, who use forest resources to survive, over-exploiting it, causing resource depletion, and deforesting to obtain new land. The Brundtland Report is an example of this type of perspective:
Those who are poor and are hungry will often destroy their immediate environment to survive: They'll tear down the woods.their cattle will over-pastorate the grasslands; they will overuse marginal lands; and in increasing numbers they will pile up in the congested cities.Report of the Global Commission on Environment and Development: Our Common Future, Report Brundtland, 1987
Neoclassical school
For the neoclassical school, the main cause of deforestation is the absence of property rights over forests. According to this view, "open access" lead to market failures and provide incentives for over-exploitation and degradation. This perspective takes some of the theoretical axes of the "tragedy of the commons" by Garrett Hardin.
Political ecology
Political ecology considers that deforestation occurs because large farmers invest in raising livestock and in grains for export, that is, grains that are not destined for direct human food consumption but for other uses, such as certain crops for the production of ethanol or the production of grains for the consumption of livestock. These large farmers put pressure on small landowners and on the forest. Small landowners must go deep into the forest in order to survive, while large farmers continue to push the edge of the agricultural frontier.
History
News
Currently, deforestation occurs mainly in Latin America, West Africa and parts of Asia. In Brazil, deforestation in 2017 increased by 28%, with more than 5,000 square kilometers of trees felled, to a large extent, due to the reform of the Forest Code during the government of Michael Temer, which reduced the protected green areas, making room for megaprojects that destroy the carioca vegetation. The states of Mato Grosso, Roraima and Pará registered the highest rates of deforestation. In Paraguay, deforestation increased by 34% compared to 2012, with more than 160,000 hectares of felled forests, seriously affecting the Cabrera Timane Nature Reserve and the Médanos del Chaco National Park. In Peru, around 150,000 hectares are deforested a year, due to the practice of illegal mining, the country has lost more than 50% of the vegetation cover of the coast.
One third of the total land is covered by forests, which represents about 4,000,000,000 (four billion) hectares. There are 10 countries that concentrate two thirds of this forest heritage: Australia, Brazil, Canada, China, the Democratic Republic of the Congo, India, Indonesia, Peru, the Russian Federation and the USA. These have been exploited for years for obtaining wood, fruits, substances produced by different species or for settlements of human population, livestock and agriculture. Indonesia, Malaysia, Paraguay, Bolivia, Zambia and Angola have been the countries that have lost the most forest area
In the last 25 years the rate of disappearance of forests has been cut in half. Since 1990, 129 million hectares of forest have been lost. The annual rate of net forest loss (which takes into account new forests being planted) has gone from 0.18% in the 1990s to 0.08% in the last five years. More countries are improving forest management and there is an increasing surface area of protected areas. Particularly relevant is the case of Europe whose forest area increased considerably, having in 2016 a third more forests than a century ago. The same phenomenon occurs in Cuba with an increase in the forested area of almost 30% in recent decades, as a result of an ambitious reforestation program. The same situation occurs in Russia, which has 20% of all forests on the planet, whose forested areas have been expanding since 1961.
In the most developed countries, forest cover suffers other effects, such as acid rain, which compromise the survival of forests, a situation that is intended to be controlled by demanding quality requirements for fuels, such as limiting the content of sulfur or desulfurization of fumes from thermal power plants and refineries.
In less developed countries, forest masses are reduced year after year, while in industrialized countries they are recovering due to social pressures, turning forests into tourist attractions and places of recreation.
While the clearing of tropical rainforest trees has attracted more attention, tropical dry forests are being lost at a substantially higher rate, mostly as a result of slash-and-burn techniques used to be replaced by crops. Biodiversity loss is generally correlated with deforestation.
In 2019, 26.1 million hectares of forest were lost annually, when from 1999 to 2019 only 26.7 million hectares had been restored. In other words, the rate of deforestation was 10 times faster than that of reforestation.
Causes
The causes of deforestation are the forces that motivate agents to destroy forest cover. There are direct and indirect causes of deforestation. Direct causes are typically known as sources of deforestation, first-level causes, or proximate causes. They are the easiest to identify. Indirect causes are the main drivers of deforestation, but there is more disagreement about them and they are more difficult to quantify.
Pearce and Brown identified two main causes of deforestation:
- Straight: Competence between humans and other species by ecological niches remaining in the land and in the coastal regions. This factor is substantially demonstrated by the conversion of forest land to other uses such as agriculture, infrastructure, urban development, industry and others.
- Indirect: It fails in economic systems to reflect the real value of the environment. Basically, many of the functions of tropical forests are not communicated and as such are ignored in decision-making. In addition, decisions to convert tropical forests are encouraged by tax and other incentives.
Other authors use the expression "immediate causes" and "underlying causes" to explain the causes of deforestation. According to this model, the underlying causes are the variables at the macroeconomic level and public policy instruments (both at the national and international level), while the immediate causes are the decision parameters that They directly affect the agents (institutions, the market, technology and infrastructures).
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Prices of agricultural products
There is sufficient evidence that an increase in the price of agricultural products stimulates deforestation. A 1987 study that analyzed 58 countries found a correlation between the total cultivated area and the price of agricultural products. The only case where there is no correlation between the price of agricultural products and deforestation is when agricultural production is subsistence agriculture. When agricultural producers are seeking to maximize their profits, the correlation between price and deforestation is higher.
Expansion of agriculture
About 60% of deforestation occurs for conversion to agricultural land.
Swidden farming or slash-and-burn farming destroys forest land to grow crops until soil nutrients are depleted or the land becomes overgrown with weeds, causing populations to move to deforest more areas. Smallholder production and the increasing number of agents practicing swidden cultivation were the main cause of deforestation in the past. Currently, the rate of conversion of forests to agricultural land is increasing and swidden cultivation is declining.
Tree plantings
Plantations should help reduce the rate of deforestation. However, the fact that plantations remove the pressure on the forest for timber production does not translate into less deforestation, but more. Timber plantations could be detrimental to tropical forest ecosystems. Tree crops and particularly rubber plantations play a larger role in deforestation in Indonesia than subsistence shifting cultivation. About half of the plantations established in tropical areas do so on land where native forests previously existed. Plantations can also promote deforestation by building roads that improve access for other agents of deforestation, such as shifting farmers.
Forestry and firewood
Logging does not necessarily cause deforestation. However, they can seriously degrade forests. Logging also catalyzes deforestation by opening roads and access roads, subsidizing the cost of cutting down remaining trees and preparing land for grain planting or grazing.
The collection of firewood and other wood-derived fuels is often concentrated in tropical dry forests and degraded forest areas. Firewood collection is not usually the main cause of deforestation in tropical moist forests, although it can be so in those places with reduced forest areas such as the Philippines, Thailand and parts of Central America. The collection of firewood was considered the main cause of deforestation and forest degradation in El Salvador.
Illegalities can also occur during the transport of timber such as illegal processing and export, false declaration at customs, evasion of taxes and export fees (Ozinga, S. 2003).
Fire and forest fires
Fire is a widely used tool to advance forest for land conversion, both for permanent agriculture and for pasture development. Fire is a useful tool in agriculture and forest management, but it can also be a cause of deforestation. Based on available data from more than 118 countries representing 65% of global forest area, an average of 19.8 million ha or 1% of all forests were reported to be significantly affected each year by forest fires. Deforestation due to road paving in Brazil also led to more frequent incidents of forest fires.
Wars and Armed Forces
There is strong evidence that military operations in the Vietnam War and other wars caused deforestation. More recently, links between warfare and the timber trade have been documented in the civil war between Burma and Thailand, where the Burmese regime sells wood to the Thais to finance their civil war against the Karen people. Forest destruction in El Salvador is a result of the war. In addition to the involvement of the military in the war, the role of the military in deforestation in Southeast Asia and South America has been documented. In Brazil, the role of the military in Brazilian politics is a major cause of deforestation in the Amazon rainforest.
Regions
Global deforestation is concentrated in three regions: South America, Africa and Oceania. Global annual deforestation is estimated at 13.7 million hectares per year, which is equivalent to the area of Greece.
30% of the global land area is covered by forests, or around 3.9 billion hectares. It is estimated that the original global forest cover was 6 billion hectares. In 2009, 2/3 of the world's forests were in 10 main countries: (1) Russia, (2) Brazil, (3) Canada, (4) United States, (5) China, (6) Australia, (7) Congo, (8) Indonesia, (9) Peru and (10) India.
Only half of this area is offset by new forests or forest growth. In addition to direct man-induced deforestation, growing forests have also been affected by climate change, increasing the risks of storms and diseases. Kyoto Protocol includes agreement to prevent deforestation but not actions to comply with itAfrica
In Africa, some four million hectares of forests were lost each year between 2000 and 2005, close to one third of the deforestation area around the world. The main cause is the conversion to a permanent agriculture of deforestation. As anti-forestation measures in Africa, a certification system is being adopted, given the global concern to obtain timber from sustainably managed forests, although the implementation of this certification remains low. Of the 306 million hectares of certified forests in the world (June 2007), about 3 million (only 1 per cent) are in Africa and most are planted forests. With about 15 million hectares of planted forests worldwide (FAO, 2006), Africa represents only 5 percent of the total.
Africa is suffering from deforestation at twice the global rate, according to the United Nations Environment Programme (UNEP). Some sources claim that deforestation has already wiped out approximately 90% of the original West African forests. Deforestation is accelerating in Central Africa. According to FAO, Africa lost the highest percentage of tropical forests on any continent during the 1980s, 1990 and early 2000s. According to FAO (1997), only 22.8 per cent of West African wet forests remain, but largely degraded. Nigeria has lost 81 per cent of its primary forests in only 15 years (1990-2005). Mass deforestation threatens food security in some African countries. One factor contributing to the high rates of deforestation in the continent is the dependence of 90% of its population on wood as heating and cooking fuel.
The research conducted by WWF International in 2006 shows that in Africa, illegal logging rates range from 50 per cent in Cameroon and Equatorial Guinea to 70 per cent in Gabon and 80 per cent in Liberia, where timber revenue played an important role in financing the civil war in Sierra Leone[13][13][13] and other regional armed conflicts until the UN Security Council imposed a ban on all timber in Liberia in 2003.
Other measures have also been carried out at the regional level against deforestation and desertification such as the Sahara Great Green Wall Initiative (UNU, 2007), with an integrated approach between agriculture, livestock and forestry.
| Total area (1000 ha) | Annual change (1000 ha) | Annual variation rate % | ||||
|---|---|---|---|---|---|---|
| 1990 | 2000 | 2005 | 1990-2000 | 2000-2005 | 1990-2000 | 2000-2005 |
| 699 361 | 655 613 | 635 412 | -4375 | - 4040. | -0,64 | - 0.62 |
North America
North America contains 17 % of the global forest area (677 million hectares). Approximately one third of the regional territory is covered by forests. Due to the wide variety of climate conditions, there is a wide range of forest ecosystems, from tropical wet forests to boreal forests. Some of the world's most productive forests are in this region.
Forest cover in the region remains stable.
North America contributed approximately 2 per cent to annual global deforestation between 2000 and 2005, although the rate of disappearance of forests has a downward trend. Climate change could intensify threats to the state of forests. The intensity and frequency of forest fires have increased in both Canada and the United States, driven by prolonged droughts (attributed to climate change) and by fire control programmes that, although successful, have inadvertently increased the amount of fuel material. Similarly, climate change is fostering pest infestations: in western Canada and the United States, the mountain pine beetle is causing tree mortality and particularly serious damage.
| Total area (1000 ha) | Annual change (1000 ha) | Annual variation rate % | ||||
|---|---|---|---|---|---|---|
| 1990 | 2000 | 2005 | 1990–2000 | 2000–2005 | 1990–2000 | 2000–2005 |
| 677 801 | 677 971 | 677 464 | 17 | -101 | 0 | -0.01. |
Central America and the Caribbean
The history of most Central American countries includes cycles of deforestation and reforestation. In the 15th century, Mayan intensive agriculture had significantly reduced forests. Before the Europeans arrived, the forests covered 500 000 square kilometres, approximately 90% of the region. Eventually, the push of "European monetary economy in Latin America" created demand for the export of primary products, which introduced the need for large quantities of clear agricultural land to produce such products. Since the 1960s, cattle ranching has become the main reason for land clearance. Wizard cattle fed with grass produced by Central American ranches (unlike cattle fed with grains raised elsewhere) was ideal for American fast food restaurants and this seemingly bottomless market has created the so-called "hamburger connection" that links the "consumer lifestyle in North America with deforestation in Central America."
In most Central American countries, net loss of forest area decreased between 2000 and 2005 compared to the previous decade, and Costa Rica achieved a net increase in that area. However, in percentage terms, Central America has one of the highest rates of forest disappearance in the world in relation to the rest of the regions, more than 1% per year in the period from 2000 to 2005.
In the Caribbean, there was a small increase in the forest area between 2000 and 2005, mainly in Cuba. Trade liberalization, which has made traditional agricultural exports such as sugar and bananas uncompetitive, is causing the abandonment of agricultural lands and their conversion into secondary forest (Eckelmann, 2005). In addition, greater emphasis is being placed on the protection of the natural environment to support the growing tourism industry. The forest area is therefore expected to remain stable or to increase in most Caribbean countries.
| Total area (1 000 ha) | Annual change (1 000 ha) | Annual variation rate % | ||||
|---|---|---|---|---|---|---|
| 1990 | 2000 | 2005 | 1990–2000 | 2000–2005 | 1990–2000 | 2000–2005 |
| 923 807 | 882 339 | 859 925 | -4147 | - 4483 | -0.46 | -0,51 |
South America
This region is the largest continuous mass of tropical rainforest in the world: the Amazon basin.
Over the past two decades,[chuckles]When?] Some countries have granted legal ownership of forests to indigenous communities, for example, Peru, 6400 million hectares; Bolivia, 1200 million hectares; Brazil, 10 300 million hectares; Colombia, 27 million hectares; Ecuador, 4.5 million hectares and Guyana, 1.4 million hectares of land, including forests. While ownership confers firm rights on communities for the sustainable use of forest resources, land disputes, sometimes violent, and the lack of implementation of the rules and regulations have allowed illegal timber occupation and exploitation in extensive areas of these forests.
All countries in South America recorded a net loss in the forest area between 2000 and 2005, except Chile and Uruguay,[chuckles]required] that presented positive trends due to large-scale industrial planting programmes. The new forests planted for industrial use, in particular in Argentina, Uruguay and, possibly, Colombia, could offset, in terms of afforested hectares, the disappearance of natural forests, but not in ecological terms. In the case of countries integrated in the North Region of Latin America such as Ecuador, Colombia and Venezuela, forest protection policies are not strict and the deforestation of the area persists, which threatens the ecological and climate balance of South America, and can have global impacts (exhibited in the Caracas FAO Agreement 2010).East Asia
This region has 18.6 per cent of the world ' s forest area, distributed in a wide variety of ecosystems, such as tropical forests, temperate forests, coastal mangroves, mountains and deserts.
The region had 734 million hectares of forests in 2005, about three million more than in 2000. However, this increase was largely the result of China ' s high rate of forest repopulation, which conceals the marked disappearance of natural forests in various countries; in total, 3.7 million hectares of forest disappeared in the region per year between 2000 and 2005.
The loss of forests is important in Southeast Asia, the second of the world's major biodiversity hotbeds. According to the 2005 FAO report, Vietnam has the second highest rate of deforestation in primary forests in the world, after Nigeria. More than 90% of the ancient rainforests of the Filipino archipelago have been cut. Other countries in Southeast Asia where significant deforestation is taking place are Cambodia and Laos. According to a TelePool documentary, deforestation is being directed by corrupt military personnel and government (forest services).
Some countries have reversed their trends in forest loss, but it is not likely that countries with greater deforestation will be able to do so. The expansion of large-scale commercial crops will be the most important cause of deforestation in the region.
The region has 136 million hectares of planted forests, almost half of the global total. Most of the planted forests are found in Australia, China, Philippines, India, Indonesia, New Zealand, Thailand and Vietnam.
| Total area (1 000 ha) | Annual change (1 000 ha) | Annual variation rate % | ||||
|---|---|---|---|---|---|---|
| 1990 | 2000 | 2005 | 1990–2000 | 2000–2005 | 1990–2000 | 2000–2005 |
| 743 825 | 731 077 | 734 243 | -1275 | 633 | -0.17 | 0.09 |
West and Central Asia
It is the region with less forests in the world, with only 4% forest cover (1% of the world's forest surface). Most of the forest area is a few countries, while in 19 countries it is less than 10% of the forest cover. About 75% of the region is arid, with low biomass productivity. The vegetation ranges from desert bushes in Central Asia and the Arabian peninsula to small mangrove areas on the Persian Gulf coast and highland meadows in Central Asia. Because of this low forest cover, trees outside the forest, especially in farms and other wooded lands, perform important productive and protective functions.
The establishment of windbreaks is an integral part of agricultural practices in most countries. The cultivation of datile palm in various countries of Western Asia has turned deserts into oasis. In the United Arab Emirates, extensive palm plantations have improved the landscape while producing substantial income.
| Total area (1 000 ha) | Annual change (1 000 ha) | Annual variation rate % | ||||
|---|---|---|---|---|---|---|
| 1990 | 2000 | 2005 | 1990–2000 | 2000–2005 | 1990–2000 | 2000–2005 |
| 43 176 | 43 519 | 43 588 | 34 | 14 | 0.08 | 0.03 |
Europe
Europe has a quarter of the world's forest resources, approximately one billion hectares, 81 percent of which are in Russia.
Virtually all countries in Europe have signed the United Nations Convention to Combat Desertification and have developed national plans that significantly hamper deforestation and reversal of other land uses, often with external support. In addition, fiscal support is provided for forest activity under the European Agricultural Fund for Rural Development, which significantly encourages tree planting. Thus, the forest area is likely to increase as agricultural land decreases.
The main threats faced by forest resources in Europe are environmental, such as fires, pest outbreaks and storms, some of which could be increased by climate change. Although the long-term impact of climate change on forests is unknown, many recent catastrophic events have been attributed to this phenomenon. There is a significant increase in the magnitude and frequency of fires, for example in the Iberian Peninsula and Russia.
| Total area (1 000 ha) | Annual change (1 000 ha) | Annual variation rate % | ||||
|---|---|---|---|---|---|---|
| 1990 | 2000 | 2005 | 1990–2000 | 2000–2005 | 1990–2000 | 2000–2005 |
| 989 320 | 998 091 | 1 001 394 | 877 | 661 | 0.09 | 0.07 |
Consequences
Atmosphere
Deforestation is a major cause of the greenhouse effect and global warming. The loss of tropical forests is responsible for approximately 20% of global greenhouse gas emissions. From According to the Intergovernmental Panel on Climate Change, deforestation, mainly in tropical areas, could account for up to a third of anthropogenic carbon dioxide emissions. But recent calculations suggest that CO2 caused by deforestation and forest degradation (excluding natural emissions from peatlands) would account for 6-17% of all anthropogenic CO2 emissions, averaging 12%. Deforestation causes CO2 to remain longer in the atmosphere. As CO2 increases, a layer is created that traps solar radiation. This radiation is converted into heat, thus causing the greenhouse effect.
Plants extract CO2 from the atmosphere through photosynthesis, keeping carbon, which they incorporate into their structure (roots, stems, leaves, flowers) in the form of organic molecules and releasing part of the oxygen. Although they also release some CO2 during their normal breathing process. Only when a tree or a forest grows can it extract carbon from the atmosphere, storing it in its tissues. Both the rotting of the wood and its burning return that stored carbon to the atmosphere. For forests to actually remove carbon from the atmosphere there must be a net accumulation of wood. One way is to cut down the trees, transform the wood into durable objects, and replace the cut trees with new ones. Deforestation can also release accumulated CO2 into the ground. Forests can be both carbon sinks and sources, depending on environmental circumstances. Old-growth forests (where the amount of plant matter does not vary significantly) alternate between behaving as net sources and net sinks (see Carbon Cycle), but this variation is negligible in relation to the enormous amount of carbon they have stored.
In deforested areas, the ground heats up faster from the sun and reaches a higher temperature, leading to greater upwelling convection currents that favor cloud formation and ultimately produce more rain. However, According to the US Geophysical Fluid Dynamics Laboratory (GFDL), models used to investigate the long-distance effects of tropical deforestation showed a large but smooth increase in temperature throughout the tropical atmosphere. These models predicted warming of less than 0.2°C in the upper tropical atmosphere (between 700 and 500 millibars). However, these models do not predict significant changes in other areas beyond the tropics. Even so, the reality may be different, because the model may contain errors and its results are never absolutely definitive.
Deforestation affects wind, water vapor and solar energy absorption, thus clearly influencing regional and global climate. Deforestation in one area can increase sandstorms in neighboring areas.
Reducing emissions from deforestation and forest degradation (REDD) in developing countries has emerged as an important complement to current climate policies. The idea is to financially compensate countries that achieve these reductions significantly.
Laymen think that tropical forests contribute significantly to atmospheric oxygen, although scientists consider the net contribution of tropical forests to be small and that deforestation has only minor effects on atmospheric oxygen levels. No However, the burning of forests to obtain arable land releases enormous amounts of CO2, which contribute to global warming. Scientists also state that tropical deforestation releases 1.5 billion tons of carbon annually into the atmosphere.
Water
Deforestation also affects the water cycle: trees draw water from the ground through their roots and release it into the atmosphere. When they disappear, the climate becomes drier. In addition, deforestation reduces the amount of water on the ground and in the subsoil, so that the remaining plants see their water availability reduced. Likewise, deforestation reduces soil cohesion, which leads to erosion, flooding, desertification and landslides.
As the tree cover is reduced, the capacity of the environment to intercept, retain and transpire the fallen rain decreases. Forested areas trap water and seep it underground; The deforested ones, on the other hand, become sources of surface water, which moves much faster than the groundwater. Forests return to the atmosphere by transpiration most of the water that falls on them as precipitation. Conversely, when an area is deforested, almost all precipitation is lost as surface water. This more rapid transport of surface water can result in flash floods and more concentrated flooding than would occur if tree cover had been maintained.. Deforestation also reduces evapotranspiration, and consequently atmospheric humidity levels, which in some cases affects rainfall in the leeward areas of the deforested area, because water is not recycled in the leeward forests, but runs down the surface and goes directly to the oceans. According to one study, in the deforested area of north and northwest China, the average annual rainfall decreased by one-third between the decade beginning in 1951 and the decade beginning in 1981.
Trees, and plants in general, have a significant impact on the hydrological cycle:
- Their cups intercept a portion of precipitation, which then evaporates again.
- Their residues on the ground (dead leaves, branches) slow down the runoff.
- These residues also change soil properties, improving their ability to retain water.
- Its roots create macropores that increase filtration to the subsoil.
- They contribute to terrestrial evaporation and reduce soil moisture by breath.
- They control the humidity of the air through the breath of their leaves. 99 % of the water absorbed by the roots is breathed.
As a result, the presence or absence of trees changes the amount of groundwater, surface water, or atmospheric water. This also changes the rate of erosion and the availability of water either for the ecosystem or for human needs. Deforestation of the plains moves cloud formation and rainfall to higher ground.
In the case of very intense and prolonged rains that exceed the normal absorption capacity of the forests, it is possible that, despite their presence, flooding occurs.
The rainforest is the source of about 30% of the planet's fresh water.
Deforestation alters weather patterns favoring warmer and drier weather, and therefore increasing drought, desertification, crop failure, melting of the poles, coastal flooding, and displacement of flora and fauna.
Floor
Natural forests have a very low rate of erosion, approximately 2 metric tons per square kilometer. Deforestation generally increases the rate of soil loss by increasing runoff and reducing the shield of plant debris. This can be an advantage in heavily washed tropical forest soils. The logging operations themselves increase erosion from road construction and the use of heavy machinery.
The Loess Plateau in China was stripped of its original forests millennia ago. Since then it has been eroding, creating deep gullies, providing the sediment that gives the Yellow River its characteristic color and favoring flooding in its lower reaches.
The disappearance of trees does not always increase the rate of erosion. In certain regions of the southwestern United States, shrubs and trees have been limiting the prairies. The trees themselves reinforce the loss of herbaceous plants on the ground shaded by their crowns. If the soil is left bare, it is very vulnerable to erosion. The US Forest Service, for example in Bandelier National Park, is studying how to restore the ecosystem, and reduce erosion, by removing trees.
Tree roots hold the soil together and, if it's shallow enough, hold it in place by binding it to bedrock. For this reason, cutting down trees on steep slopes with topsoil can increase the risk of landslides and threaten the lives of nearby residents.
Biodiversity
Deforestation decreases biodiversity and causes the extinction of many species. More than half of terrestrial plant and animal species live in tropical rainforests. The loss of forested areas has resulted in a degraded environment, with less biodiversity. Forests support biodiversity by providing a habitat for numerous species of fauna and flora, some of which may have medicinal applications. As forest biotopes are irreplaceable sources of new medicines (such as taxol), deforestation it can irretrievably destroy the genetic wealth that provides edible plants with resistance to pests.
As tropical rainforests are the most diverse ecosystems on Earth and contain about 80% of known biodiversity, the disappearance of significant areas of tree cover has resulted in degradation of the soil and an environment of less biodiversity. A study in Rondonia (Brazil) shows that deforestation also kills off the microbial community that is responsible for recycling nutrients, cleaning water, and removing pollution.
It is estimated that every day we are losing 137 species of plants and animals (including insects) due to the deforestation of the forests, which means 50,000 species per year. Authors such as Lewin et al. claim that deforestation of rainforests is contributing to the Holocene mass extinction.
The known (not estimated) rates of extinction of mammals and birds due to deforestation are much lower, about one species per year. But if you extrapolate to all species, you get the figure of approximately 23,000 each year. It has been predicted that 40% of the animal and plant species in Southeast Asia could disappear in the s. XXI. These predictions have subsequently been questioned when it was observed in 1995 that in Southeast Asia most of the original forest had been transformed into monoculture plantations, but that the potentially threatened species are few, and that the trees and the rest of the flora they remain stable and widespread. Scientific understanding of the extinction process is insufficient to make accurate predictions about the impact of deforestation on biodiversity. Most predictions of biodiversity loss caused by forestry operations are based on species-specific models. area, assuming that if the forest declines, species diversity will similarly decline. However, many of these models have been shown to be wrong and habitat loss does not necessarily lead to large-scale species loss. that species-area models overestimate the number of endangered species specific to the areas that are being deforested, and much more in the case of more widespread species (present both in areas that are being deforested and in those that are being left untouched).
A 2012 study of the Amazon predicts that, despite the lack of extinctions so far, up to 90% of those predicted will occur in the next 40 years.
Fragmenting forests, or even laying roads in them, has a strong impact on biodiversity: a study published in Nature in 2017 shows that 85% of animal species living in a jungle are affected by the boundary effect. 46% increase their abundance, and 39% (in general, the most threatened species, and especially small amphibians, large reptiles and medium-sized flightless mammals) decrease it.
Humans
Deforestation causes new viral or infectious diseases to appear, or diseases that are controlled by forests to spread faster and more intensely. A review of the scientific literature in 2007 revealed that there is a relationship between deforestation and malaria. Another scientific study in 2010 showed that 4% deforestation in the Amazon rainforest in Brazil led to a 43% increase in malaria cases. Another study in Brazil showed that the degradation of a forest within a radius of less than 5km2 is a triggering factor for the presence of malaria.
In 2000, the FAO concluded that "the role of population dynamics in a local setting can range from decisive to insignificant," and that deforestation can result from "a combination of population pressure and economic, social, and environmental stagnation." economic and technological conditions".
Actions against deforestation
REDD Program
Major international organizations, including the United Nations and the World Bank, have begun to develop programs to combat deforestation. The umbrella term REDD (Reducing Emissions from Deforestation and Degradation) describes these programs, which use direct monetary or other incentives to encourage developing countries to limit or reverse their deforestation. Funding has been discussed, but an agreement was reached at the fifteenth conference of the parties (COP 15) to the United Nations Framework Convention on Climate Change (UNFCCC) in Copenhagen (December 2009) whereby countries Developed countries pledged to contribute new and additional resources, including forestry and investments channeled by international institutions, which will be close to 30 billion dollars for the period 2010-2012.
Significant work is underway on tools to monitor how developing countries meet the REDD targets to which they have committed. These tools, which include remote monitoring of forests by satellite imagery and other data sources, including the Center for Global Development's FORMA (Forest Monitoring Initiative) and the forest carbon monitoring portal of the Group on Earth Observation (GEO). Methodological guidance for forest monitoring was also given importance at COP 15. The environmental organization Partners to Avoid Deforestation is leading the campaign for the development of REDD through funding from the US Government. In 2014 FAO, with various partners, launched Open Foris — a suite of open source software to help countries collect, produce and disseminate information on the state of their resources forestry. These programs (there is a Spanish version) are used for the entire life cycle of the forest inventory, from the assessment of needs, design, planning, collection and management of field data, estimative analysis and dissemination. Tools are included for remote image processing, as well as REDD and MRV (measurement, communication and verification) international communications.
To assess the overall implications of emission reductions, the countries receiving the most attention are those with high forests and high rates of deforestation (HFHD) and those with low forests but high rates of deforestation. deforestation (LFHD). HFHD countries are considered Brazil, Cambodia, Equatorial Guinea, Malaysia, North Korea, East Timor, Solomon Islands, Venezuela and Zambia. Instead they are noted as LFHD Afghanistan, Benin, Botswana, Burma, Burundi, Cameroon, Chad, Ecuador, El Salvador, Ethiopia, Ghana, Guatemala, Guinea, Haiti, Honduras, Indonesia, Liberia, Malawi, Mali, Mauritania, Mongolia, Namibia, Nepal, Nicaragua, Niger, Nigeria, Pakistan, Paraguay, the Philippines, Senegal, Sierra Leone, Sri Lanka, Sudan, Togo, Uganda, Tanzania and Zimbabwe.
Environmental laws to protect forests
Several countries have implemented laws to protect forests, such as the native forest laws implemented by Argentina and Chile.
A scientific study analyzed the impact of Argentina's Native Forest Law, focusing primarily on the land use planning mechanisms required by law and the responsibility of provincial and municipal governments in carrying out such planning. The study analyzed the provinces of Salta, Santiago del Estero and Chaco (the most affected by deforestation in Argentina) and found that the management of local governments could have an impact in reducing deforestation.
Payments to conserve forests
In Bolivia, deforestation in upper river courses has caused environmental problems, including soil erosion and decreased water quality. An innovative bill to remedy the situation calls for downstream water users to pay upstream landowners to conserve their forests. Owners receive US$20 to conserve trees, avoid polluting livestock practices, and promote biodiversity and carbon sequestration by the forest on their property. They also receive USD 30 towards the purchase of a beehive, which compensates them for the conservation of two hectares of forest for five years, in order to protect a water source. The income per hectare of the honey collected amounts to five dollars a year, so that in five years it amounts to 50 USD for the owner. The project is carried out by Fundación Natura Bolivia and the environmental organization Rare, with the support of Alianza Clima and development.
In China, the State pays 7,500 yuan per hectare per year (equivalent in 2018 to around 937 euros) for five years to farmers in areas designated as priority for reforestation if they abandon their crops, plant trees and dedicate themselves to taking care of them, cleaning the foliage.
In countries like Costa Rica, Mexico and Mozambique, there are so-called PSAs (Payment for Environmental Services), which seek to financially reward the preservation of the environment. Despite its purposes, various studies have shown that its effects are modest in avoiding deforestation.
Increase in input prices
The available evidence on the price of inputs for agricultural production (such as fertilizers and pesticides) is not conclusive. A study in certain areas of Latin America suggested that an increase in the price of fertilizers can reduce deforestation. Different studies found evidence that an increase in the price of other inputs, such as seeds, pesticides and tools reduces deforestation.
Increase in wages for farmworkers
Available evidence suggests that higher wages for farmworkers reduce deforestation by making farming and forestry activities more expensive. Other higher-paying job offers in non-agricultural areas also reduce deforestation. deforestation.
Land ownership
Transferring ownership of forest land to indigenous peoples is said to be an efficient way to protect them. This includes protecting such rights where existing laws grant them, such as in the Indian Law of Transferring these rights in China, perhaps the greatest agrarian reform of the contemporary age, is argued to have increased forest cover. In Brazil, forest areas whose ownership has been transferred to indigenous peoples suffer less permanent felling than even those national parks.
Farming methods that do not require clearing forests
Clearing the forest and planting using traditional farming methods yields little. Some new agricultural methods that offer much higher yield per hectare (and therefore allow less forest to be cut, or not at all, if applied to land where traditional methods were used) are: hybrid plants, greenhouses, urban gardens or hydroponics. These new methods often depend on chemical inputs (fertilizers, pesticides) to keep their yield high. In cyclical agriculture (so called as opposed to shifting cultivation, in which a tribe clears an area of forest, cultivates it, and, when the land is depleted, abandons it to clear a new area) cattle graze on land left untouched. fallow, fertilizing it and preparing it for the next sowing. Crop rotation is a form of cyclical agriculture. On the other hand, biointensive agriculture obtains very high yields on very small plots without using chemical substances. Intensive agriculture, on the other hand, can deplete soil nutrients at an accelerated rate. The most promising approach, however, is forest gardening (usual, but unfortunate translation of the term forest gardening; unfortunate because, in Spanish, gardening is ornamental, not nutritional; the French translation, nutrient forest gives a better idea of the meaning) in permaculture, which consists of agroforestry systems, carefully designed to imitate natural forests, favoring animal and plant species of nutritional, timber and other uses. These systems have low dependence on fossil fuels and chemicals, require little maintenance, are highly productive, and have little impact on soil, water quality, and biodiversity.
Monitoring deforestation
There are multiple suitable and reliable methods for monitoring deforestation. One of them is the visual interpretation of aerial photos or satellite images. It is labor intensive, but does not require high-level training in automated image processing or a heavy investment in computers. Another method is hotspot analysis.) using expert opinion or low-resolution satellite imagery to identify these areas, and then perform detailed digital analysis on high-resolution satellite imagery. Deforestation is typically assessed by quantifying the amount of deforested area, 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 focus on protecting forests and developing alternative land uses to prevent further deforestation. The rate of deforestation and the total area deforested have been widely used to monitor deforestation in many regions, including the Brazilian Amazon by INPEN (Instituto Nacional de Pesquisas Espaciais). A satellite view of the Earth is available.
Forest management
Forest management or forest management is the branch of forest engineering that deals with the administrative, economic, legal, social, etc. activities of forests, and follows scientific and technical principles of forestry, protection and regulation. It can be about natural forest management or the management of artificial or reforested forests.
In the areas where the cultivation of tala and burning is practiced (also called friction and burning), the change to cut and carbonize (instead of burning, with flame, in open fire and complete combustion, the plant matter cut, turning it into charcoal by incomplete combustion and spreading coal on the ground), is not only a durable method of carbon fixation. It is also extremely enriching for the soil. Mixing the charcoal with biomass creates the preta terra, one of the richest soils and the only known that is self-regenerated.
Efforts have been made for centuries to stop or stop deforestation, because it has long been known that it can cause such serious environmental damage that lead to the disappearance of entire societies. In Tonga, the rulers developed policies to prevent conflicts between short-term gains to convert forests into croplands and the long-term problems resulting in the disappearance of the forest. In Japan, during the Tokugawa shogunate (17th-XVIIIth century) the shoguns developed an advanced long-term planning system to stop and even reverse the deforestation of the previous centuries, by replacing the wood with other products and a more efficient use of the land that had been cultivated during centurias. In 16th-century Germany, landowners developed forestry to deal with the problems of deforestation. However, these policies tend to be limited to ecosystems with enough rain, without dry season and with very young soils (result of vulcanism or glaciers). In older and less fertile soils trees grow too slowly to make forestry economic, while in areas with a long dry season, there is always a risk that a forest fire will destroy the trees planted before they mature.Sustainable Practices
Certification that a forest is managed sustainably, such as that provided by the Program for the Endorsement of Forest Certification (PEFC) or Forest Stewardship Council (FSC) global systems It contributes to containing deforestation by creating a market for products from sustainably managed forests. According to the FAO, “A prerequisite for the adoption of sustainable forest management is the demand for sustainably produced products and the willingness of consumers to pay for the higher costs involved. Certification represents a shift from regulatory approaches to market incentives to promote sustainable forest management. By promoting the positive attributes of forest products from sustainably managed forests, certification focuses on the demand side of environmental stewardship." In contrast, Australia's Rainforest Rescue argues that the standards of organizations like FSC are too connected to the timber industry and therefore do not guarantee sustainable and socially responsible forest management. That in reality the certification monitoring systems are inadequate and several cases of fraud have been documented in the world.
Some nations have taken steps to increase the number of trees on Earth. In 1981 China created the national tree planting day and in the decade that began in 2001 the forest cover has reached 16.55% of the territory when in the one that began in 1991 it was only 12%.
Using bamboo, which is technically not a tree, but rather a grass (specifically a grass) for firewood, leads to a cleaner burn than tree wood, and because bamboo matures much faster than wood, it reduces deforestation, because supplies can be replenished more quickly.
Reforestation
Reforestation is an operation in the field of forestry aimed at repopulating areas of deforestation in the historical and recent past (usually 50 years). By extension, it is also called reforestation, although the term afforestation would be more correct, to the plantation more or less massive of trees, in areas where these did not exist, at least in recent historical times (equally about 50 years). Also called reforestation to the set of techniques needed to be applied to create a forest mass, formed by woody species.
In many parts of the world, especially in East Asia, reforestation and afforestation are increasing forest areas. The amount of forest has increased in 22 of the 50 nations of the world with more forests. Asia, together, won a million hectares of forest between 2000 and 2005. In addition, the tropical forest in El Salvador grew more than 20% between 1992 and 2001. Based on these trends, a study estimates that the global forest area by 2050 will be 10% — an area of India's extension — greater than that of 2006.
In China, where large-scale forests have been destroyed, it has been a legal obligation of every trained citizen, between 11 and 60 years, to plant 3 to 5 trees annually, or to do the equivalent amount of work in other forest services. The Chinese Government maintains that, since 1982, at least one billion trees have been planted each year and that 50 000 square kilometres of forest area have been recovered annually. In 2016 this obligation is no longer in force, but every 12 March in China is the planted holiday. In addition, the project Gran Muralla Verde de China is underway, which, planting trees, aims to curb the expansion of the Gobi desert. Although due to the high percentage of trees that die after planting them (up to 75%), the project is not very successful, the forest area in the north of the country has passed from 5 to 12.4 %. In China, the forest area has increased 47 million hectares since the decade it began in 1971. The total number of trees in 2001 was estimated at 35 billion. Another ambitious proposal for China is the aerial system of reforestation and erosion control.
In Africa, with a similar name, the Great Green Wall of Africa, another desert containment initiative (the Sahara in this case) is being carried out through the planting of trees. It has been proposed to use marine water greenhouses.
In Western countries, the growing demand of consumers for forest products that have been cultivated and harvested in a sustainable way is making forest owners and the timber industry increasingly accountable for their forest management and logging practices.
The U.S. Rainforest Rescue Program Arbor Day Foundation uses its donations to buy and preserve forests before they can be purchased by timber companies. This foundation thus protects the lands of deforestation. It also isolates the way of life of the primitive tribes that inhabit them. Other organizations such as Cool Earth, Community Forestry International, The Nature Conservancy, WWF/Adena, Conservation International, African Conservation Foundation and Greenpeace also focus on preserving forest habitats. In particular, Greenpeace has identified the still intact forests and published this information on the Internet. For its part, the World Resources Institute has drawn a simpler thematic map showing forests around 6000 BC and at the beginning of S. XXI (much smaller). These maps show the amount of reforestation required to repair the damage caused by humanity.Tree plantings
To meet the global demand for wood, foresters Botkins and Sedjo propose high-yield tree plantations. It has been calculated that plantations producing 10 m³ (cubic meters) of wood per hectare annually could supply all the wood demanded by international trade using only 5% of the current forest area. Natural forests only produce between 1 and 2 m³ per hectare, and therefore 5 to 10 times more land would be required to meet the demand. Forestry engineer Chad Olivier proposes a mosaic of high-yield forests interspersed with preserved lands.
Planted forests increased worldwide from 4.1 to 7.0% of the total forest area between 1990 and 2015 In 2015 they totaled 280 million hectares, an increase of around 40 million hectares since 2010. 18% of these 280 million are exotic or introduced species, while the rest are native to the country where they have been planted. In eastern and southern Africa, South America and Oceania, planted forests are mainly introduced species: 65, 88 and 75% respectively. In North America, Western and Central Asia, and Europe, the proportions of introduced species are much lower: 1, 3, and 8% of the total planted area, respectively.
In Senegal, on the west coast of Africa, a youth-led movement has helped plant more than six million mangrove trees. These trees will protect villages from storms and provide habitat for local flora and fauna. The project started in 2008 and in 2010 the Senegalese government has already been asked to protect the new mangroves.