It thus covers the various forms of soil degradation, adverse human impacts on water resources, deforestation, and lowering of the productive capacity of rangelands. Soil degradation needs to be recognised, alongside climate change, as one of the most pressing problems facing humanity. However, since the effects of soil loss vary depending on the underlying soil type, soil loss, by itself, is not an appropriate proxy measure for productivity decline. Causes and impacts of land degradation and desertification. Prevention and remediation of soil erosion and degradation. Loss of natural fertility of soil because of loss of nutrients. Productivity of cultivated land may decline from severe soil degradation. Because soil degradation contributes to land degradation, it also means that it creates a significant loss of arable land. Soil erosion and sedimentation in surface water sources affects the. In this report, land degradation is defined as a negative trend 4 in land condition, caused by direct or indirect humaninduced processes. Soil erosion leads to losses in soil and crop productivity, pollution of land and water resources, and a loss of farm income. Soil degradation is the loss of lands production capacity in terms of loss of soil fertility, soil biodiversity, and degradation. In turn, unsustainable land use is driving land degradation.
Soil degradation includes erosion, salinization due to freshwater removal, soil loss following erosion after deforestation or overgrazing, compaction and crusting of soils, which can be caused by cattle trampling, and waterlogging with impaired water movement oldeman et al. Soil degradation is, in itself, an indicator of land degradation. Chapter 2 types of land degradation food and agriculture. Here, we selected 50 plots on degraded land caused by long. For example, planting crops at a location with heavy rainfall and steep slopes would create scientific and environmental concern regarding the risk of soil erosion by water, yet farmers could view. But, in the field, further variables are used as indicators of the occurrence of soil degradation. Severe soil erosion and landsliding affect 17% of the land area of italy.
With a high rate of population growth, subsistencebased rural economy, and increasingly intense rainfall. Degraded soil diminishes food production and leads to soil erosion, which in turn contributes to desertification. View fulltext this is an open access article distributed under the creative commons attribution license which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Overgrazing of rangelands, poor cultivation of croplands, deforestation and urbanization are some of the land use practices that result in increased soil erosion and subse. The term land degradation involves both soil and vegetation degradation. Soil erosion and sedimentation in surface water sources affects the supply and quality of water. It encompasses physical soil erosion, chemical salinity and alkalinity, pollution and biological deterioration pollution and. Plant community characteristics and functional traits as. Indirect drivers of land degradation in grenada the indirect drivers of land degradation in grenada are the driving forces of the direct causes of land degradation. Land degradation is the major consequences of direct interference of human activities in the natural phenomenon. Sustainable land use can help to reduce the impacts of agriculture and. Deforestation causes fast degradation when the soil is steep sloppy or easily erodible. Pdf land degradation, particularly soil erosion, is currently a major challenge for nepal. Soil erosion was discussed as a process by which soil carbon is lost.
Without soil and plants the land becomes desertlike and unable to support life. Land degradation, particularly soil erosion, is currently a major challenge for nepal. The approach to considering soil or land degradation has recently incorporated land function as opposed to earlier approaches that considered primarily soil properties such as soil organic matter or carbon content, structural condition, degree of salinization, compaction or bulk density, or degree of erosion. Sustainable land use can help to reduce the impacts of agriculture and livestock, preventing soil degradation and erosion and the loss of valuable land to desertification. Study of the degree of development of erosion on sloping. We measured aboveground plant characteristics, root functional traits, and soil properties to explore their responses to the degree of erosion and to identify the main. Nearly 10 million hectares of arable land are lost to erosion and other forms of soil degradation every year 1 countries all over the world are battling with worrisome sight of deepening gullies crisscrossing the landscape and barren fields stripped of the fertile topsoil. View fulltext this is an open access article distributed under the creative commons attribution license which permits unrestricted use, distribution, and reproduction in. Soil loss from conventionally tilled land exceeds the rate of soil formation by. Land degradation is a process in which the value of the biophysical environment is affected by a combination of humaninduced processes acting upon the land. The semiarid zones of the south of italy and the islands of sicily and sardinia are particularly prone to erosion by virtue of a combination of climatic factors and high relative relief. Pollution of water resources from the contamination of. Furthermore, world population growth, combined with increasing climate change and related natural hazards, is likely to worsen the impact of soil erosion and land degradation. Aug 24, 2018 soil erosion is the most serious precursor of soil degradation that comes with global implications.
Reduced soil nutrients reduce crop and forage yields while the expansion of areas affected by invasive species reduces the land available for livestock grazing. Similarly the devastating impacts of these disasters left a wave of soil erosion particularly on steep slopes with limited protection. Soil erosion and land degradation have been increasing in ethiopian highlands due to the existence of arable land 90 %, high human population 90% and livestock density 60% which resulted in. Countries all over the world are battling with worrisome sight of deepening gullies crisscrossing the landscape and barren fields. This process is experimental and the keywords may be updated as the learning algorithm improves. About 40% of the worlds agricultural land is lost on the account of soil quality depreciation caused by agrochemicals and soil erosion. The world is losing 10 ha of arable land each minute5 ha to soil erosion, 3 ha from salinity, and 2 ha by.
Major causes and effects of soil erosion on the environment. In this guide, we look at what land degradation is including the sub land and soil issues it encompasses, along with the causes, the effectsimpacts, and the potential. Land degradation in somalia is negatively affecting land productivity. Land degradation soil degradation is the decline in soil quality caused by its improper use, usually for agricultural, pastoral, industrial or urban purposes. This erosion is the dominant form of soil degradation troeh et al. Land degradation is, usually, the result of complex interrelationships between biophysical and socioeconomic issues which affect many people and their land, specially in the tropics and developing countries. Research by the economics of land degradation initiative in. Wind erosion is a major geomorphological force, especially in arid and semiarid regions. Careless agricultural practices, pollution and deforestation cause lots of soil degradation in the world. Land degradation as the land use section earlier in this chapter shows, demands on the land for economic development and pressures from a burgeoning population are leading to unprecedented land use change.
This study takes the degradation of soil resources as its focus. When land is cleared for farming, the trees and plants are removed and the soil is no longer protected. According to global assessment of soil degradation glasod, deforestation is the main cause of soil erosion by wind in about 98% of the area. For example, the land productivity classes include class i, extremely high. The health of soil is a primary concern to farmers and the global community whose livelihoods depend on well managed agriculture that starts with the dirt beneath our feet. Soil degradation causes include agricultural, industrial, and commercial pollution.
The most effective method to prevent erosion is to increase the vegetation cover on soil, thus preventing wind and water erosion. Soil degradation is any type of problem that removes soil in an area or makes highquality soil become poor. Land degradation was not addressed in a comprehensive way. Soil erosion and land degradation in southern italy. Erosion rate soil erosion soil loss sediment yield land degradation these keywords were added by machine and not by the authors. The older agricultural areas of the northeast have long been particularly affected, but the highest soil erosion rates are currently being observed in the western parts of the high lands. Grenada land degradation neutrality national report. The present rate of land degradation is estimated at 5 to 7 million hectares per year, suggesting that 0. Land degradation and desertification, largely due to deforestation and unsustainable land use, are amongst the most pressing problems facing the world today. The soil integrates a variety of important processes involving vegetation growth, overland flow of water, infiltration, land use and land management.
Principal processes of land degradation include erosion by water and wind, chemical degradation comprising acidification, salinization, leaching etc. Land degradation and rehabilitation in ethiopia society at large is also suffering from uncertain information about the rates of land use change and land degradation. Effects include land degradation, soil erosion and sterility, and a loss of biodiversity, with huge economic costs for nations where deserts are growing. About 40% of the worlds agricultural land is lost on the account of soil quality depreciation. Soil degradation is the decline in any or all of the characteristics which make soil suitable for producing food. These elements contribute to a significant amount of soil quality depreciation annually. Soil erosion is the most widely recognised and most common form of land degradation and, therefore, a major cause of falling productivity. Despite wide variations in the figures, and considerable uncertainty about the degradation parameters, even the most conservative methods lead to large estimates of the cost of soil erosion, comparable at least to the annual investment in research and.
The paper suggests some rules of thumb for identifying the priority areas for government and donor intervention, including the need for targeted research on the productivity. Solutions need to be developed and introduced which address both issues simultaneously. Leaving unploughed land strips between ploughed ones, known as strip cropping, also help reduce erosion. Several types of soil degradation exist and are a threat to natural forests and planted crops. The human dimension of land degradation and forest degradation. It is an insidious process removing the most productive soil layer. Soil loss from conventionally tilled land exceeds the rate of soil formation by 15 2 orders of magnitude medium confidence. Sediment deposition in adjacent water bodies is driven by soil erosion, which is the most widely recognized and most common form of land degradation. Soil degradation occurs through the deterioration of the physical, chemical and biological properties of soil that results in soil compaction, salinisation, acidification, and soil loss from wind and water erosion.
A problem with defining land degradation is that what one group of people might view as degradation, others might view as a benefit or opportunity. Land degradation indicators and management options. The literal translation of arable land is able to be ploughed. Causes of soil degradation and methods for soil conservation. Soil erosion is the most serious precursor of soil degradation that comes with global implications.
Land degradation has accelerated during the 20th century due to increasing and combined pressures of agricultural and livestock production overcultivation, overgrazing, forest conversion, urbanization, deforestation, and extreme weather events such as droughts and coastal surges which salinate land. Land degradation food and agriculture organization of the united. It is viewed as any change or disturbance to the land perceived to be deleterious or undesirable. This is particularly worrisome since, according to the uns food and agriculture organization, some 83% of subsaharan african people depend on the land for their livelihood, and food production in africa will have to increase almost 100. Land degradation by soil erosion is still one of the most severe environmental issues of our time. We find that the most important cause of land degradation in the philippines is soil erosion. May 01, 2019 land degradation soil degradation is the decline in soil quality caused by its improper use, usually for agricultural, pastoral, industrial or urban purposes. Soil erosion has been and remains one of the major causes of that degradation. The results of the research prove that soil erosion is based on natural and anthropogenic factors. Assessment of land degradation by erosion soil loss by water, e. Soil erosion is the displacement of the upper layer of soil, it is one form of soil degradation. The severity of the problem of depletion of this vital resource is only now becoming widely appreciated. Different processes of land degradation also confound the available statistics on soil and or land degradation. However, erosion can speed up when land is degraded.
Overstocking and overgrazing inappropriate farming techniques such as deep ploughing land 2 or 3 times. Effects of land use change on land degradation reflected. The result is a loss of land productivity with impacts on livelihoods and the. Mar 02, 2020 land degradation is the blanket term usually used to describe a number of land and soil degradation issues such as soil contamination, soil erosion, desertification, and more. Roots of trees and plants act as anchors to the soil. Nearly 10 million hectares of arable land are lost to erosion and other forms of soil degradation every year 1. Research by the economics of land degradation initiative in 2015 calculated that soil degradation is. Land degradation, soil erosion and soil conservation pmf ias.
Land degradation indicators and management options in. Causes of soil erosion erosion occurs when farming practices are not compatible with the fact that soil can be washed away or blown away. Soil degradation examples include decline in soil fertility, adverse changes in alkalinity, acidity or salinity, extreme flooding, use of toxic soil pollutants, erosion, and deterioration of the soil s structural condition. It is also a major source of land degradation, evaporation, desertification, harmful airborne dust, and crop damageespecially after being increased far above natural rates by human activities such as deforestation, urbanization, and agriculture wind erosion is of two primary varieties.
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