In the case of soil erosion, some of the effects may appear to be reversible, through checking further erosion by soil conservation programmes and restoring lost nutrients and organic master. Soil erosion is the most serious precursor of soil degradation that comes with global implications. Already, myanmar ranks thirteenth in the world in terms of losses from extreme weather, and widespread environmental degradation in the country adds to vulnerability. The most effective method to prevent erosion is to increase the vegetation cover on soil, thus preventing wind and water erosion.
This erosion is the dominant form of soil degradation. Land degradation is a broader term referring to the decline of the entire ecosystems ability to provide goods and services. 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. Some impacts, such as soil erosion, are a consequence of many direct drivers. In addition to erosion, soil quality is affected by other aspects of agriculture. The soil degradation index in the settlements is more than five times greater in the communal areas than in the commercial areas n 367. Water erosion is in many ways very similar to wind erosion. Estimates of erosion are essential to issues of land and water management, including sediment transport and storage in lowlands, reser. Efficiency of four different seeded plants and native vegetation as cover crops in the control of soil and carbon losses by water erosion in olive orchards. The economics of land degradation and desertification unccd second scientific conference. It also highlights state and impacts of degradation, along with policy and program responses. It is the fairly uniform removal of soil in thin layers from the land surface, often. Leaving unploughed land strips between ploughed ones, known as strip cropping, also help reduce erosion. Soil degradation is a serious global environmental problem and may be exacerbated by climate change.
Wind erosion is a common cause of land degradation in the arid and semi arid grazing lands of inland queensland. Water and wind are the two main mechanisms by which soil is eroded and transported. The objective of this study was to identify and map the extent and severity levels of land degradation caused as a result of soil erosion by water on the kenyan section of lake victoria basin lvb. Effects of soil erosion on soil properties as related to crop. Overgrazing and poor farming techniques can also lead to soil erosion, but it is important to remember that not all causes are human. Distinguish between soil erosion and land degradation. Preserving the worlds land from soil degradation ific.
Soil science institute of athensnational agricultural research foundation. T value tolerable erosion equilibrium between soil gains and losses. Concurrently with the growing human population, soil erosion, water availability, climate change due to fossil fuel consumption. The economics of land degradation in africa eld initiative. Oct 29, 2017 land resources, soil erosion and land degradation 1. A conceptual model of natural land degradation based on regressive pedogenesis in semiarid tropical. Overview and stocktaking of land degradation in general and in africa. The main agents of erosion are water, wind and gravity. It encompasses physical soil erosion, chemical salinity and alkalinity, pollution and biological deterioration pollution and.
Land degradation assessment in drylands lada project 173annex 1 types and forms of erosion by water and by wind p badlands. Evidences suggest that the rate of encroachment of arable land is high and is. Land degradation is a process in which value of land is affected by human activities. This is a pdf file of an unedited manuscript that has been accepted for. Pdf the impact of land management practices on soil erosion and land. Photograph of a compacted zone of soil immediately below the plough layer in a cropping soil. Wildfire effects on soil erodibility of woodlands in nw spain. Land degradation the process of land degradation in southern africa is blamed on water and wind erosion, sedimentation, longterm destruction of vegetation and diminution of the bioresources. Where land has been lost by gullying, or severe sheet erosion has removed the soil clown to a gravelly residue, degradation is clearly irreversible. This erosion is the dominant form of soil degradation troeh et al. Soil degradation by accelerated erosion is a serious problem and will remain so during the 21st century, especially in developing countries of the tropics and subtropics. Factors that influence water and wind erosion the potential for a land area to erode is determined by several key factors.
Methodologies for soil erosion and land degradation assessment in mediterranean. Rapid erosion modeling in a western kenya watershed using. Land degradation, soil erosion and soil conservation pmf ias. Soil degradation is the loss of land s production capacity in terms of loss of soil fertility, soil biodiversity, and degradation. Soil erosion and land degradation in the highlands of. These impacts include compaction, loss of soil structure, nutrient degradation, and soil salinity. Grenada land degradation neutrality national report. Chapter 7 economic consequences of land degradation. Degraded environments deprive agricultural systems of vital ecosystems services that conserve soil fertility and moister, control pests, and stop erosion. Effects of soil erosion on soil properties as related to crop productivity and classification w. The present rate of land degradation is estimated at 5 to 7 million hectares per year, suggesting that 0.
Land degradation is a broader definition which includes degradation due to pollution, wind erosion etc. Erosion results in the loss of topsoil that is not eas ily replaced. International soil reference and information centre, wageningen. The study identifies overgrazing as a driver of land degradation in. There are several issues related to land degradation that intersect with other concerns. Panos panagos, gabriele standardi, pasquale borrelli, emanuele lugato, luca montanarella and francesco bosello, cost of agricultural productivity loss due to soil erosion in the european union. Different processes of land degradation also confound the available statistics on soil and or land degradation. Compaction compaction is where soil particles pack together increasing soil density and reducing pore space.
The change in the characteristic and quality of soil which adversely affect its fertility is called as degradation. Food and agriculture organization, electronic files and web site. Pdf on jun 20, 2007, rajendra p shrestha and others published land degradation in afghanistan find, read and cite all the research you need on researchgate. Soil physical damage is an increasingly serious problem for agriculture. These factors are interrelated in their effect on the potential for erosion. Erosion preceded by the destruction of the crumb structure due to the impact of falling raindrop on the surface of soil is termed as splash erosion. Land degradation indicators and management options in the. This process is experimental and the keywords may be updated as the learning algorithm improves.
Land degradation is the temporary or permanent lowering of the productive capacity of land unep, 1992b. Pdf exploring the impact of overgrazing on soil erosion and land. In turn, unsustainable land use is driving land degradation. This study takes the degradation of soil resources as its focus. The variability in terrain and soils makes erosion control unique to. Soil degradation a major threat to humanity summary. Land degradation is a composite term it has no single readily.
Pdf knowledge on land use changes dating back to the period of neolithic to high. Land degradation has a wider scope than both soil erosion and soil degradation in that it covers all negative changes in the capacity of the ecosystem to provide goods and services including biological and water related goods and services and in ladas vision also landrelated social and economic goods and services. This study therefore set out to determine the effects of land use types on land degradation as reflected by soil properties soil bulk density, soil organic carbon, nitrogen, and phosphorus along the mara river. Chapter 5, methodology describes harmonization process developed in the gis core and followed for obtaining realistic estimates of the degraded and.
Update and operationalize legislations to control sand mining and to reduce land degradation due to gem mining. In mexico land degradation is an important factor in mexicos national economy impacting 65% of the national land area. Soil degradation in india is estimated to be occurring on 147 million hectares mha of land, including 94 mha from water erosion, 16 mha from acidification, 14 mha from flooding, 9 mha from wind. It is one of the processes leading to desertification. Pdf status of soil erosion or land degradation in india. With a high rate of population growth, subsistencebased rural economy, and increasingly intense rainfall events in the monsoon season, nepal is prone to several forms of land degradation, such as floods, landslides, and soil erosion. The main impact of agriculture on soil degradation is erosion, salinization. Agrometeorology in relation to the control of soil erosion. This leaflet explains the different types of erosion on the north coast. 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. Classic gullies are characterized by headward migration and enlargement through a combination of headcut erosion and gravitational slumping, as well as the tractive stress of concentrated flows. Soil degradation is a lowering of the quality or productivity of soil. 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. Pdf soil degradation is one of the major global threats.
Trafficking by animals as well as by vehicles and cultivation are the primary causes of this form of soil degradation. Raindrops hit exposed soil with great energy and easily dislodge the soil particles from the surface. Erosion of soil by water occurs throughout the world, but especially in the more humid regions. Vegeta tion can regenerate from a degraded state as long as the seed stock remains viable and there is soil for seeds to germinate and grow in. Erosion and sediment control national management measures to control nonpoint pollution from agriculture 491 to crops, and are farmed around. Soil erosion refers to the removal of top soil which is considered to be most fertile. Land degradation is defined as the temporary or permanent decline in the productive capacity of the land, and the diminution of the productive potential, including its major land uses e. Land produc vity and soil erosion on a na onal scale. Erosion occurs when soil is left exposed to rain or wind energy. In tushe, the soil erosion risk model was applied to assess the current state and general risk of erosion. After data deduplication, 1572 documents on land degradation. In this report, land degradation is defined as a negative trend 4 in land condition, caused by direct or indirect humaninduced processes including anthropogenic. In the present study landsat satellite images for the years of 1977, 1990 and 2000 have been used to identify the change in degraded land in the region. Soil and land degradation are interrelated issues and often come up in the same context.
Water erosion affects mostly farms however infrastructure is sometimes affected. The soil integrates a variety of important processes involving vegetation growth, overland flow of water, infiltration, land use and land management. Estimates of global and regional land area affected are tentative and subjective. Land degradation and desertification, largely due to.
Soil is subject to a series of induced degradation processes, which humannamely are displacement of soil material, and internal soil deterioration dwivedi, 2002. Construction degrades the soil by replacing productive land with structures, leaving soil exposed to the forces of erosion and compaction. The condition of the soil is one of the best indicators of land degradation. Effects of land use change on land degradation reflected. Significant wind erosion occurs when strong winds blow over lighttextured soils that have been heavily grazed during periods of. Land degradation in the form of soil erosion is a major problem in the semiarid region of lower chambal valley. The decline in quantity and quality of soil it includes erosion by wind and water biological degradation loss of humus physical degradation loss of structure, permeability, compaction chemical degradation reduced fertility, salinisation, changing ph, toxicity if degradation is so severe that land becomes unusable it is termed desertification. Estimation of soil erosion risk using the universal soil loss. Soil degradation causes include agricultural, industrial, and commercial pollution. The main impact of agriculture on soil degradation is erosion, salinization, compaction, reduction of organic matter, and nonpoint source pollution. Principal processes of land degradation include erosion by water and wind, chemical degradation comprising acidification, salinization, leaching etc. Land degradation soil degradation is the decline in soil quality caused by its improper use, usually for agricultural, pastoral, industrial or urban purposes. Dregne soil erosion is the main reason why desertification is irreversible.
Soil science institute of athensnational agricultural. Widespread soil erosion is found for the bronze age, iron age and roman. More land is cleared and less left fallow, which can deplete the soil and increase water runoff. Introduction soil erosion represents one of the most serious land degradation problems 1.
Erosion rate soil erosion soil loss sediment yield land degradation these keywords were added by machine and not by the authors. Both types of erosion increase in severity when there is a lack of land cover vegetation. 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. Erosion due to faulty practices in crop production, for example, has resulted in the loss of millions of tonnes of topsoil every year. This leads to reduced soil fertility and degraded land. The loss of soil from land surfaces by erosion is widespread and reduces the productivity of all natural ecosystems as well as agricultural, forest, and pasture ecosystems. This includes soil erosion by water and wind, deterioration in soil physical. Present values of costs of inaction against soil erosion by erosion and poverty classes and. It is based on the rusle revised universal soil loss equa on calcula ng erosion caused by rainfall and surface run o based. Just as soil erosion is a component of soil degradation, soil degradation is a component of land degradation.
Land degradation is the temporary or permanent lowering of the productive. Soil degradation pdf the term soil degradation refers to processes that causes a reduction in its. Land degradation, particularly soil erosion, is currently a major challenge for nepal. 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. It is viewed as any change or disturbance to the land perceived to be deleterious or undesirable. Erosion is a natural process but is often intensified by human land use practices. Soil degradation results from construction, contamination, and erosion.
The impact of land degradation on food productivity library wur. Plant growth is severely affected by water erosion. Similarly the devastating impacts of these disasters left a wave of soil erosion particularly on steep slopes with limited protection. Prevention and remediation of soil erosion and degradation.
The result is a loss of land productivity with impacts on livelihoods and the. Yet, its extent, severity, and economic and environmental impacts are debatable. 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. The world is losing 10 ha of arable land each minute5 ha to soil erosion, 3 ha from salinity, and 2 ha by. Status and trends of land degradation and restoration horizon ird. The human dimension of land degradation and forest degradation.
While data is not precise, it is estimated that losses of nutrients and productivity in agricultural and grazing areas costs over. Rangeland degradation and resultant soil erosion often occurs in. The land degradation section of this report deals with causes of land degradation, both in terms of deterioration of soil quality and loss of land. Soil degradation is, in itself, an indicator of land degradation. Land resources land resources can simply be defined as resources available by land.
With around 120 thousand km 2 lost to degradation every year, and over 3. The severity of the problem of depletion of this vital resource is only now becoming widely appreciated. This loss of cropland to the effects of soil erosion often results in the creation. Soil degradation by erosion lal 2001 land degradation. Land solid earth surface that is not permanently covered with water.
Read this article to learn about the meaning, factors responsible, prevention and control measures of land degradation. Soil erosion and degradation on mediterranean type. 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. The ipbes assessment report on land degradation and restoration. It thus covers the various forms of soil degradation, adverse human impacts on water resources, deforestation, and lowering of the productive capacity of rangelands. Erosion degree very severe, value 4 linear erosion also occurs in areas that are. The effects of soil erosion go beyond the loss of fertile land. The word erosion is derived from the latin rodere meaning to gnaw, the same root that gives us the word rodent. Pdf quantification of past soil erosion and land use land cover. Integrated erosion control iec measures linking remote.
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