How Do We Define Afforestation And Deforestation Environmental Sciences Essay

The effects of an increasing population, growing pollution and the consequent decrease in forest area on the environment are well known. Afforestation is the answer to some extent, but needs to be carried out in a structured way with thorough knowledge of local environment, vegetation, soil type and socio-economic issues; not knowing or ignoring local conditions can prove extremely dangerous to the ecosystem.

A sustainable and well-planned afforestation project helps improve soil conservation, catchment management and water quality. Such a project can also act as a wind barricade, as in the case of the The Great Green Wall Project in China. A very ambitious afforestation project that has spanned 70 years and 4,480km, it involves the building of a tree wall skirting the Gobi Desert. The tree wall is being built with the sole aim of fighting and acting as a barricade to ferocious sandstorms originating from the desert.

Afforestation projects undertaken without a complete understanding of the surroundings can cause additional environmental damages. For instance , fast-growing trees commonly used in timber plantations consume huge amounts of water, hence depleting water resources around the area. There are also concerns about irreversible changes in the soil caused by exotic species. For example, pine trees are known to turn the soil acidic. The water from the soil eventually trickles down to local streams and water bodies, which, in turn, causes harm to both the water and land ecosystems.

The concern mainly arises with large-scale monoculture tree plantations in Third World countries. Such plantations are usually set up for the purposes of abundant and cheap supply of raw materials to industrialised countries. A number of non-government organisations have joined hands to form a global network in order to share information and implement joint action against such plantations.

In India, because of its large population, there has been growing demand for lands that are used in primary industries, such as arable land, grazing land and forestry land. And a considerable amount of cultivation and afforestation has taken place in response to such demand. This study deals with these three types of lands and analyzes the economic impact in India of cultivation and afforestation, using a Computable General Equilibrium (CGE) model. The model explicitly addresses substitution between traditional goods (fuelwood, cattle dung, and draft animals) and modern goods (fossil fuel, chemical fertilizer, and capital such as agro machinery). The results show that the two types of land use change (cultivation and afforestation) have many contrasting effects on various indices.

Due to population pressures, in India demand has been increasing for lands that are used in primary industries. This includes arable land, grazing land and forestry land. In response to this situation, many cultivation and afforestation projects have been conducted. In the 1950s and 1960s, numerous cultivation initiatives were actively carried out and approx. 700,000 hectares per year were cultivated. However, because India has achieved food self-sufficiency and since scarce land remains to cultivate, in recent years very little cultivation has taken place. Instead , many irrigation projects have been conducted and the focal emphasis of the nation’s arable land policy has shifted from quantitative expansion to qualitative enhancement.

China has deforested most of its historically wooded areas. China reached the point where timber yields declined far below historic levels, due to over-harvesting of trees beyond sustainable yield.[3] Although it has set official goals for reforestation, these goals were set for an 80 year time horizon and are not significantly met by 2008. China is trying to correct these problems by projects as the Green Wall of China, which aims to replant a great deal of forests and halt the expansion of the Gobi desert. A law promulgated in 1981 requires that every citizen over the age of 11 plant at least one tree per year. As a result, China currently has the highest afforestation rate of any country or region in the world, with 47,000 square kilometers of afforestation in 2008. However, the forest area per capita is still far lower than the international average. An ambitious proposal for China is the Aerially Delivered Re-forestation and Erosion Control System

North Africa:-

In North Africa, the sahara forest project coupled with the Seawater Greenhouse has been proposed. Some projects have also been launched in countries as Senegal to revert desertification. At present (2010) African leaders are discussing the combining of national countries in their continent to increase effectiveness. In addition, other projects as the Keita project in Niger have been launched in the past, and have been able to locally revert damage done by desertification.

Europe:-

Europe has deforested the majority of its historical forests. The European Union has paid farmers for afforestation since 1990, offering grants to turn farmland back into forest and payments for the management of forest. Between 1993 and 1997, EU afforestation policies made possible the re-forestation of over 5,000 square kilometres of land. A second program, running between 2000 and 2006, afforested in excess of 1000 square kilometres of land (precise statistics not yet available). A third such program began in 2007.

In Poland, the National Program of Afforestation was introduced by the government after World War II, when total area of forests shrank to 20% of country’s territory. Consequently, forested areas of Poland grew year by year, and on December 31, 2006, forests covered 29% of the country (see: Polish forests). It is planned that by 2050, forests will cover 33% of Poland.

According to FAO statistics, Spain had the fastest afforestation rate in Europe in the 1990-2005 period. In those years, a total of 44,360 square kilometers were afforested, and the total forest cover rose from 13,5 to 17,9 million hectares. In 1990, forests covered 26,6% of the Spanish territory. As of 2005, that figure had risen to 35,4%. Spain today has the third largest forest area in the European Union, after Sweden and Finland.

Iran

Iran is considered a low forest cover region of the world with present cover approximating seven percent of the land area. This is a value reduced by an estimated six million hectares of virgin forest, which includes oak, almond and pistacio. Due to soil substrates, it is difficult to achieve afforestation on a large scale compared to other temperate areas endowed with more fertile and less rocky and arid soil conditions. Consequently, most of the afforestation is conducted with non-native species, leading to habitat destruction for native flora and fauna, and resulting in an accelerated loss of biodiversity.

DEFORESTATION:-

DEFINITION:

Deforestation is the clearance of forests by logging and/or burning (popularly known as slash and burn) Deforestation is the permanent destruction of indigenous forests and woodlands. The term does not include the removal of industrial forests such as plantations of gums or pines. Deforestation has resulted in the reduction of indigenous forests to four-fifths of their pre-agricultural area. Indigenous forests now cover 21% of the earth’s land surface

Causes and Effects of Deforestation

Trees are one of the most important aspects of the planet we live in. Trees are vitally important to the environment, animals, and of course for us humans. They are important for the climate of the Earth, they act as filters of carbon dioxide, they are habitats and shelters to millions of species, and they are also important for their aesthetic appeal. However , the trees on our planet are being depleted at a very fast rate. According to some estimates, more than 50 percent of the tree cover has disappeared due to human activity.

ROOT OF CAUSES OF DEFORESTATION:

http://t1.gstatic.com/images?q=tbn:ANd9GcSRNsylTo0bYxhYiESWK3QiGD_Ih95eEOFBXWj5vKVKBMnhfsA&t=1&usg=__vHcZj32oCodhQS3Qwvk3z40Ln4Q=Almost one-third of the earth’s land is covered with forest. They play an important role in sustaining life. They house over 60% of the world’s biodiversity and provide human beings with many products such as food, medicine, fuel, lumber, paper etc. There are two main causes of deforestation. The primary and most common reasons for deforestation are known as the direct causes. Logging, overpopulation , urbanization, dam construction etc are under direct causes. The other main cause of deforestation is known as natural causes since they are brought by the Mother Nature. n increase in population also means an increase in produce consumption. Thus, rainforests are destroyed and converted to cattle pasture to supply the burgeoning demand for meat. In Central America, almost half of the rainforests have been slashed and burned for cattle farming in order comply with foreign demands. Twenty-five per cent of the Amazon’s forests have also been destroyed for cattle ranches.

Lack of government legislation for land reforms has also cleared the forest especially in developing countries like of the South East Asian nations. People in that region are among the poorest in the world and are desperate for a piece of land. Unequal distribution of resources has led these people to find their way to exploit the forests.

Another reason that denudes the forest is exploitative economic development schemes and the powerlessness of government to safeguard its resources . Poor countries in their attempt to increase their revenues are in a way exploiting their resources like the forests. Timber is exported to reduce the national debt. Countries rich in mineral resources open their doors to multinational mining corporations that clear the forests as they go with their operations. The government especially those belonging in the Third World cannot curb commercial logging and implement a total log ban in exchange to higher foreign exchange rates . Development projects like dams, roads, and airports contracted by the government also cause deforestation.

While most causes of deforestation occur due to human activities, there are uncontrolled causes of deforestation such as forest fires, volcanic eruption, and typhoon.

Forest fires are started by lightning, and strong winds help to spread the flames. Drought in the forest has increased the amount of flammable bush and debris on the forest floor. Forest fires destroy immeasurable amount of valuable timber. They kill not only trees but also other living things.

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Effects of Deforestation:

There are a number of adverse effects of deforestation, such as:

Erosion of Soil:

When forest areas are cleared, it results in exposing the soil to the sun, making it very dry and eventually, infertile , due to volatile nutrients such as nitrogen being lost. In addition, when there is rainfall, it was hes away the rest of the nutrients, which flow with the rain water into waterways. Because of this, merely replanting trees may not help in solving the problems caused by deforestation, for by the time the trees mature, the soil will be totally devoid of essential nutrients. Ultimately, cultivation in this land will also become impossible, resulting in the land becoming useless. Large tracts of land will be rendered permanently impoverished due to soil erosion.

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Disruption of the Water Cycle:

Trees contribute in a large way in maintaining the water cycle. They draw up water via their roots, which is then released into the atmosphere. A large part of the water that circulates in the ecosystem of rainforests, for instance, remains inside the plants. When these trees are cut down it results in the climate getting drier in that area.

Loss of Biodiversity:

The unique biodiversity of various geographical areas is being los t on a scale that is quite unprecedented . Even though tropical rainforests make up just 6 percent of the surface area of the Earth, about 80-90 percent of the entire species of the exist here. Due to massive deforestation , about 50 to 100 species of animals are being lost each day. The outcome of which is the extinction of a functions of forests is to absorb and store great amounts of water quickly when there are heavy rains. When forests are cut down, this regulation of the flow of water is disrupted, which leads to alternating periods of flood and then drought in the affected area.

Climate Change:

It is well known that global warming is being caused largely due to emissions of greenhouse gases like carbon dioxide into the atmosphere. However, what is not known quite as well is that deforestation has a direction association with carbon dioxide emissions into the atmosphere. Trees act as a major storage depot for carbon, since they absorb carbon dioxide from the atmosphere, which is then used to produce carbohydrates, fats, and proteins that make up trees. When deforestation occurs, many of the trees are burnt or they are allowed to rot, which results in releasing the carbon that is stored in them as carbon dioxide. This, in turn, leads to greater concentrations of carbon dioxide in the atmosphere.

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POSITIVE AND NEGATIVE CONSEQUENCES OF DEFORESTATION:

The positive consequences of deforestation –

Depending on the needs of the social group concerned, deforestation has made it possible for communities to be built. Forests make way for residential houses, office buildings and factories. Governments are able to build roads to make trade and transport easier and therefore more convenient to residents.

Deforestation can also mean the conversion of forest land to productive land for agricultural uses. This results in better and more abundant production of food and materials, virtually eradicating periods of want and lack. Economically, deforestation has contributed much in giving many communities the opportunity to make positive changes in their lives.

The negative consequences of deforestation –

Unfortunately, the negative consequences of deforestation far outweigh its positive effects. Here are a few of them:

1. Exposing soil to heat and rain. When forests are cleared, soil cover, which consists mainly of vegetation, is removed as well. This exposes the bare soil to extreme conditions produced by the sun’s heat and rainwater.

With these activities alternating, the soil quickly compacts. As rainwater flows, it will wash out the nutrients and other organic materials that make the soil rich and fertile. Add to that the frequent activities of tilling, cropping and grazing which gradually results to the degradation of the soil’s quality.

These practices are specially a concern in areas where forest zones are drier. Agriculture practice on top of deforestation can result to the desertification of many areas. Desertification is also a direct result of the demand for the soil to produce more (as a consequence of the increase in human population), thereby decreasing to a significant degree the land’s carrying capacity.

2. Flooding. Deforestation can result to watersheds that are no longer able to sustain and regulate water flows from rivers and streams. Trees are highly effective in absorbing water quantities, keeping the amount of water in watersheds to a manageable level. The forest also serves as a cover against erosion. Once they are gone, too much water can result to downstream flooding, many of which have caused disasters in many parts of the world.

As fertile topsoil is eroded and flooded into the lower regions, many coastal fisheries and coral reefs suffer from the sedimentation brought by the flooding. This results to negative effects in the economic viability of many businesses and fatalities in wildlife population .

3. Non-suitability of areas for conversion. Most of the areas that have undergone deforestation are actually unsuitable for long-term agricultural use such as ranching and farming. Once deprived of their forest cover, the lands rapidly degrade in quality, losing their fertility and arability.

The soil in many deforested areas is also unsuitable for supporting annual crops. Much of the grassy areas are also not as productive compared to more arable soils and are therefore not fit for long-term cattle grazing.

4. The displacement of indigenous communities and their traditional way of life. When governments decide to offer forests for deforestation mainly to open up areas for ‘civilized’ communities, access to forest resources by indigenous peoples are ignored. In fact, indigenous peoples are hardly included in economic and political decisions that directly affect their lives. This encroachment ignores their rights as much as it takes away the resources that their ancestors have bestowed upon them.

5. The loss in the number of biodiversity. This is probably the most serious consequence of deforestation . Put simply, it means the destruction and extinction of many plant and animal species , many of whom remain unknown and whose benefits will be left undiscovered.

Environmental problems:-

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Atmospheric:-

Deforestation is ongoing and is shaping climate and geography.

Deforestation is a contributor to global warming, 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.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. 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%. Trees and other plants remove carbon (in the form of carbon dioxide) from the atmosphere during the process of photosynthesis and release oxygen 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 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”.

Rainforests are widely believed by laymen to contribute a significant amount of world’s oxygen, although it is now accepted by scientists that rainforests contribute little net oxygen to the atmosphere and deforestation will have no effect on atmospheric oxygen levels.However, the incineration and burning of forest plants to clear land releases large amounts of CO2, which contributes to global warming.

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

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

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.[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 transpiring. 99% of the water absorbed by the roots moves up to the leaves and is transpired.

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 planet’s fresh water.

Soil:-

Deforestation for the use of clay in the Brazilian city of Rio de Janeiro. The hill depicted is Morro da Covanca, in Jacarepaguá

Undisturbed forests have a very low rate of soil loss, approximately 2 metric tons per square kilometer (6 short tons per square feet).[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.

Ecological:-

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

Since the tropical rainforests are the most diverse ecosystems on Earth and about 80% of the world’s known biodiversity could be found in tropical rainforests, removal or destruction of significant areas of forest cover has resulted in a degraded environment with reduced biodiversity.

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. Others state that tropical rainforest deforestation is contributing to the ongoing Holocene mass extinction.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. 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 stable.

Scientific understanding of the process of extinction is insufficient to accurately make predictions about the impact of deforestation on biodiversity.[56] Most predictions of forestry related biodiversity loss are based on species-area models, with an underlying assumption that as the forest declines species diversity will decline similarly.However, many such models have been proven to be wrong and loss of habitat does not necessarily lead to large scale loss of species.[57] 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.

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. 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.

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.

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.

Control:-

Reducing emissions

Major 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. 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 and the Group on Earth Observations’ Forest Carbon Tracking Portal. Methodological guidance for forest monitoring was also emphasized at COP-15 The environmental organization Avoided Deforestation Partners leads the campaign for development of REDD through funding from the U.S. government.

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Farming

New methods are being developed to farm more intensively, such as high-yield hybrid crops, greenhouse, autonomous building gardens, and hydroponics. These methods are often dependent on 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]

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, while during the seventeenth and 18th centuries in Tokugawa, Japan, 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 16th 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