· Erosion is the process by which soil and rock are removed from the Earth's surface by natural processes such as wind or water flow, and then transported and deposited in other locations. Soil erosion is a natural process that we cannot stop. And there is many factors that can affect on its physical process and how soil erosion work. First the Rainfall that can cause soil erosion soil erosion essaysSoil erosion is a gradual process that occurs when the actions of water, wind, and other factors eat away and wear down the land, causing the soil to deteriorate or disappear completely. Soil deterioration and low quality of water due to erosion and run off has often become a sev The main effects of soil erosion are as follows. 1. Loss of Soil: The top-soil is lost by erosion which is the most fertile section, having evolved over centuries of soil-forming processes. Due to formation of gullies and ravines, valuable agricultural lands are lost. 2. Harmful Effects of Erosion on Organic Matter and Soil Structure: Erosion of upper layer of soil decreases the content of Estimated Reading Time: 7 mins
Essay on Soil Erosion | Environment
Essay 1. Meaning of Soil Erosion: All land use activities, particularly those which are poorly managed, involve destruction or disturbance, to a greater or lesser extent, of natural and semi-natural ecosystems.
Almost invariably, however, it is those ecosystems, in equilibrium with their environment, which offer most effective protection to the soil that supports them. A major consequence of ecosystem destruction and disturbance is that of soil degradation.
This has been defined as the decline in soil quality caused through its misuse by human activity. More specifically it refers to the decline in soil productivity through adverse changes in nutrient status, organic matter structural stability and concentrations of electrolytes and toxic chemicals. In many instances, these have soil erosion essay to a serious decline in soil quality and productivity and it is only in soil erosion essay decades that the finite nature of soil as a resource has become widely recognised.
Soil degradation is not a new phenomenon. Archeological evidence suggests that it soil erosion essay been on-going since the beginning of settled agriculture several thousand years ago. The decline of many ancient civilizations, soil erosion essay the Mesopotamians of the Tigris and Euphrates valleys in Iraq, the Harappans of the Indus valley in Pakistan and the Mayans of Soil erosion essay America, was due in part to soil degradation.
More recently an event of major significance was the dustbowl which occurred in the Great Plains of the American Midwest during the s. At this time, soil erosion essay, intensive agricultural practices, soil erosion essay, employed in the eastern states, were transferred to the drier Midwest where the soils are lighter textured and more susceptible to erosion. A number of years of drought, combined with crop failure and destruction of the protective organic-rich topsoil, resulted in severe wind erosion.
According to the Global Assessment of Soil Degradation project, about 15 per cent of the global land area between 72°N and 57°S is degraded. Of this, an area slightly less than that of India about million hectares is strongly degraded, largely as a result of deforestation million hectaresinappropriate management of cropped land 83 million hectares and overgrazing 75 million hectares.
In recent decades, the global rate of soil degradation has increased dramatically and is likely to increase further as we approach the soil erosion essay century; in it was estimated at million ha a -1 and is set to rise beyond 10 million ha a -1 by the year The effects of soil degradation are not restricted to the soil alone, but have a number of off-site implications.
Soil erosion, for example, is often associated with increased incidence of flooding, siltation of rivers lakes and reservoirs and deposition of material in low-lying areas. These problems may be compounded in areas where infiltration capacity is reduced due to soil erosion essay, hard setting or induration of soils.
Salinisation and sodification of soils are often associated with poor quality irrigation water while soil acidification is commonly linked with acidification and aluminium contamination of surface waters, soil erosion essay.
Leaching of fertilizers and pesticides from agricultural soils may also lead to contamination of surface and shallow ground waters. In addition, contamination of soils by urban and industrial pollutants, such as heavy metals and radionuclides, soil erosion essay, may soil erosion essay to toxic accumulation in arable produce and in herbage for grazing animals, thus having important implications for human health.
The extent of soil degradation is influenced by a number of factors, many of which are interrelated, namely soil characteristics, soil erosion essay, relief, climate, land use and socio-economic and political controls Fig, soil erosion essay. In many studies of soil degradation and its wider environmental implications, the socio-economic and political controls are often overlooked, or at least not examined in any detail, perhaps because of the difficulties associated with the collection of reliable and comparable data.
Increasingly, however, soil erosion essay, these controls on land use systems are being viewed as central to the issue of soil degradation, particularly in the developing world.
Management of soil degradation, whether at a global, regional or local scale, is clearly a complex issue and represents one of our most challenging environmental problems. The problem requires a holistic, multidisciplinary approach involving the collaborative and coordinated efforts of ecologists, agronomists, soil scientists, soil erosion essay, hydrologists, engineers, sociologists and economists.
Moreover, the involvement of government and non-government organisations, aid agencies and the farmers themselves is essential to the success of research and development in this area. Such involvement should facilitate the implementation of education, training and incentive programmes.
Imposition from above of high-technology, high-cost solutions by technical experts from developed countries is certainly not the answer in the developing world. Inevitably, such solutions are not economically viable and low-technology, low-cost options—such as low external input agriculture, agroforestry and social forestry—are often the only answer. Hence, the approach to soil conservation has shifted in recent years soil erosion essay a rather techno centric standpoint to a more soil erosion essay position.
Central to this approach are the concepts of land husbandry and sustainable development, which place emphasis on the land-users themselves rather than on the technical experts and advisors. This chapter aims to examine a selection of the most pressing soil degradation problems and, in each case, the causal factors, on and off site effects and management strategies will be considered.
Essay 2. Generally, rates of soil formation are very low, with profiles developing at a rate of about 1 cm every years; assuming an average bulk density of 1.
It is important to differentiate between natural or background erosion and erosion which has been accelerated largely as a result of human activity. In contrast, rates of accelerated erosion commonly exceed 10 t ha soil erosion essay a -1 and sometimes exceed t ha -1 a Some of the highest soil erosion rates have been observed in the Loess Plateau area of China and in the Himalayan foothills of Nepal, where values in excess of t ha -1 a -1 have been recorded.
Similarly, in India, gully erosion results in a loss of about 8, ha of land per year. The extent of soil erosion is governed by a number of factors. Those of particular importance include erosivity of the eroding agent, erodibility of the soil, slope steepness and length, land use practices and conservation strategies, soil erosion essay.
These factors are summarised in the Universal Soil Loss Equation which has been used widely in the modelling and prediction of soil erosion e. Although widely used, this model has been the subject of extensive criticism.
For example, it assumes that a vegetation cover soil erosion essay always protective which is not necessarily the case; erosion on land with a good cover of crops planted in rows can be greater than on land which is sparsely vegetated.
It is also water erosion based and cannot be used in areas affected extensively by wind erosion, soil erosion essay. More specifically, it focuses on rill and inter-rill erosion and is not easily applied to areas where gully and stream bank erosion are widespread. Its universal nature has also been questioned particularly in terms of its application to tropical soils, soil erosion essay.
Furthermore, it should be emphasised that this model does not consider the wide range of socio-economic and political factors which play a crucial role in terms of their influence on the degree of soil erosion which will be examined later. Alternative models include SLEMSA Soil Loss Estimator for Southern Africa and CREAMS Chemicals Run-off and Erosion Arising From Agricultural Management Systems.
Land use is perhaps the most significant factor influencing soil erosion, for two main reasons. First, soil erosion essay, many land use practices leave the soil devoid of a protective vegetation cover, or with only a partial cover, for significant periods of time and second, they involve mechanical disturbance of the soil.
Specific aspects of land use often associated with accelerated soil erosion include expansion and intensification of arable cultivation, overgrazing, deforestation, certain forestry practices, site clearance in preparation for urban and industrial construction and a number of recreational activities such as walking and soil erosion essay. Arable cultivation has expanded and intensified dramatically in recent decades.
Relatively steep slopes, formerly covered by grass or tress, have been converted to arable cropping, while an increased use of heavy agricultural machinery has resulted in compaction of the soil. This, in turn, has led to reduced infiltration capacity, particularly along wheel tracks, thus resulting in increased surface run-off and erosion. Similarly, increased reliance on tillage activities, throughout the cropping cycle, has rendered soils more susceptible to erosion.
This problem has been compounded by the decline in levels of soil organic matter and hence structural stability, largely in response to increased use of inorganic fertilizers. In addition, the tendency to increase field sizes on arable land has meant that there are fewer physical breaks and barriers in the landscape, such as tree lines, hedgerows and walls, to restrict erosion. Susceptibility to erosion is further increased if land is cultivated with the slope rather than parallel to the contours.
Overgrazing is soil erosion essay common in drought-affected parts of the developing world, soil erosion essay, such as the Sahel region of sub-Saharan Africa and the rangelands and communal lands of eastern and southern Africa. In a study of the impact of grazing on soils soil erosion essay the Savanna region of Nigeria, for example, Aweto and Adejumbobi attribute enhanced surface run-off and erosion to compaction of the soil and destruction of the protective vegetation cover by grazing animals and to the adoption of inappropriate burning strategies.
Deforestation, largely for logging and wood fuel purposes, is also common in many parts of the developing world. Trees are well-known for their ability to protect soils from erosion, particularly on steeply sloping terrain.
Their root systems and the organic material which they supply help to stabilise the soil, while water uptake and canopy interception serve to reduce the frequency and intensity of surface run-off. In addition to deforestation, many forestry practices are associated with accelerated soil erosion, including the needle leaf forestry programmes which have become widespread in many areas of upland Britain.
Here, erosion is most serious during the soil erosion essay stages of land preparation and drainage and after harvesting. In relation to urban and industrial land use, construction and associated disturbance of land may lead to increased soil erosion.
Even certain soil erosion essay activities have been implicated in this problem, including walking and skiing. A number of socio-economic and political factors have been associated soil erosion essay accelerated soil erosion, particularly in the developing world.
These include population pressure, skewed land resource distribution; poverty and marginalization, increasing demand for wood fuel, soil erosion essay, inappropriate land tenure and farm policies, soil erosion essay, small size of land-holdings and poor infrastructure. In many developing countries, population growth is rapid and the demand for agricultural land and wood fuel is ever increasing Table Furthermore, agricultural systems are characterised by a skewed land resource distribution where a minority of affluent and powerful landowners control a majority of the land area.
The poorest farmers are thus forced onto marginal land, which is particularly susceptible to erosion, and often end up in a vicious spiral of debt. Rural-urban migration, abandonment of land and increased soil erosion are often responsible to this poverty trap situation Fig. In many parts of the developing world, large areas of land are utilised for mono-cultivation of cash crops, which are not necessarily best-suited to soil conditions, rather than for indigenous mixed food cropping.
Such commercial pressure on agricultural systems, as well as contributing to soil erosion essay problem of marginalization discussed above, has a detrimental effect on soil quality and is unlikely to be sustainable in the long term.
There is also little political support soil erosion essay terms of education, training and incentive schemes to encourage farmers to adopt more sustainable land use practices. The establishment of appropriate and comprehensive soil conservation and land husbandry programmes is further hindered by the small size of land-holdings and the large number of farmers involved Table The on and off-site effects of soil erosion are considerable.
At the global scale, it is estimated that unless soil erosion essay conservation measures soil erosion essay introduced on all cultivated land, million ha of potentially productive rain-fed crop land will be lost and agricultural production expected to decrease by almost 20 per cent, by the year Undoubtedly, these effects will be felt most severely in those developing countries which are least able to cope with the problem.
It should be noted that the deterioration in soil productivity is disproportionate to the amount of soil eroded, as it is the nutrient rich and structure- supporting constituents in the topsoil which are lost most readily. Overcropping causes the soil to deteriorate when too many crops are grown on the same land without the farmer replacing lost mineral and organic material, soil erosion essay. In natural conditions, as plants grow, they extract the valuable mineral and organic plant nutrients from the soil; when they die, they decay and soil erosion essay their nutrients, soil erosion essay, returning them to the soil which is thus enriched for other plants that come after them, soil erosion essay.
But when men cultivate crops, they harvest them and carry the crops elsewhere to be sold or consumed. There is no replacement at all. If the farmer year after year, grows cotton which is very exhaustive of nitrates, and does not add any manure or fertilizers, the soil is bound to become poorer until the farm has to be abandoned. This is the growing of a single type of crop, year after year, such as cotton or wheat. The crop is constantly using up particular types of minerals from the soil which it needs.
As a result some minerals in the soil may be completely exhausted and fertility may decline if fallow periods, fertilizers or crop rotations are not used to balance soil properties, soil erosion essay. This is the constant use of the land for several crops every year. If there is not a constant supply of fertilizer this quickly exhausts the soil and yields rapidly decline, soil erosion essay.
This type of cultivation of forest clearings can be very harmful. The destruction of the soil erosion essay by fire means that the soil is no longer protected from the full force of heavy tropical rain, nor is it consolidated and held together by plant roots.
It is therefore quickly washed soil erosion essay. After the ladangs are abandoned the forest is allowed to grow again, and, if the plot is not cleared again for a long time about 20 yearsthe rest or fallow period is long enough for the soil to regain its humus and mineral content. If, however, as usually happens, the plots are re-cleared after only a few years or one plot is occupied for too many years, soil erosion essay, the soil cannot recuperate and it becomes permanently infertile.
It may be eroded into deep gullies or invaded by lalang grass and is thus made soil erosion essay either for farming or for forest.
Soil: What is soil? What is soil erosion and degradation?
, time: 2:46What is soil erosion?, Sample of Essays
Essay Contents: Essay on the Meaning of Soil Erosion Essay on the Occurrence of Soil Erosion Essay on the Causes of Soil Erosion Essay on the Impact of Soil Erosion Essay on the Process of Soil Erosion Essay on the Measurement of Soil Erosion Essay on the Conservation of Soil ErosionEstimated Reading Time: 9 mins · Erosion is the process by which soil and rock are removed from the Earth's surface by natural processes such as wind or water flow, and then transported and deposited in other locations. Soil erosion is a natural process that we cannot stop. And there is many factors that can affect on its physical process and how soil erosion work. First the Rainfall that can cause soil erosion The main effects of soil erosion are as follows. 1. Loss of Soil: The top-soil is lost by erosion which is the most fertile section, having evolved over centuries of soil-forming processes. Due to formation of gullies and ravines, valuable agricultural lands are lost. 2. Harmful Effects of Erosion on Organic Matter and Soil Structure: Erosion of upper layer of soil decreases the content of Estimated Reading Time: 7 mins
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