Soil erosion is the displacement of the upper layer of soil, it is one form of soil degradation. Soil erosion is caused by the action of water, wind, grazing animals and human activity. Effects of bank vegetation and incision on erosion rates. This type of erosion threatens our ability as humans to sustain our global population with food and fiber, and is closely linked to economic vitality. Soil erosion is a natural process in which particles of soil are moved by wind and water, and displaced to another location. Effects of vegetation cover and land use changes on soil. Soil degradation is a serious global environmental problem and may be exacerbated by climate change. Soil erosion can deplete the fertility of the soil thereby making the soil unsuitable for the growing of crops and vegetables.
Effects of soil erosion on the environment soil erosion is an ongoing process that affects each site in a slightly different way. Depending on the local landscape and weather conditions, erosion may be very slow or very rapid. Overgrazing adversely effects soil properties, which results in reduced infiltration, accelerated runoff and soil erosion. The universal soil loss equation usle was first developed in the 1960s by. Soil erosion assessment using gis and revised universal. Assessing soil erosion although soil erosion has been taking place very slowly in natural. Erosion does not occur uniformly across a field mainly because of the runoff flow network and nonuniform topog raphy. Helping north coast landholders reduce soil erosion. Effects of rainfall patterns on runoff and soil erosion in. Total soil erosion on all cropland and land in crp declined since 1982 as well. Soil erosion itself seriously impairs the quality of soil and its natural recovery rate, but it is not the worst problem that can occur. The effect that grazing has on a plant depends on the timing, frequency and intensity of grazing and its opportunity to regrow. It is one of the processes leading to desertification. Soil loss equations can assist contractors in quantifying soil loss and the effects of bmps for risk management decisions.
A part of the process is the detachment of soil material by the impact of raindrops. Contamination of soil will definitely have adverse effects on. Vegetation can 76 decrease soil erosion by providing structural support through root development and increasing soil 77 cohesion by supplying organic material and influencing. When soil erosion is severe, soil erodes faster than it can be renewed. The least developed economies have been found to experience the highest estimates of soil erosion rates. The spatial and temporal variability of this phenomena are very high within a catchment. Dryland salinity occurs in unirrigated landscapes figure 1. In the selection of site for building a house, higher percentage 47%, 40%, 53% and 50% for nkrankwanta, asankragua, mampong and agona respectively of the respondents considered no factor. A portion of the energy from raindrop impact is first spent to deform peds i. Fire that destroys vegetation and triggers erosion has the same effect. Only few of them con sidered factors as, soil type and slope table 3. The rate of erosion can be increased by activities other than those of humans.
Understanding soil erosion in irrigated agriculture. Sheet erosion soil erosion is characterised by the downslope removal of soil particles within a thin sheet of water. Selecting a management strategy to maximize production is nearly impossible. Soil erosion soil erosion is the detachment and movement of soil material. When erosion occurs naturally, soil is relocated at about the same rate.
Twelve soil profiles representing eight soil series were selected from the. In spite of heavy investments in research and development, the global rates of accelerated erosion are now presumbly higher than ever before. Wind erosion is a common cause of land degradation in the arid and semi arid grazing lands of inland queensland. Four kinds of accelerated water erosion are commonly recognized. This research was autho rized by the 1928 buchanan amendment to the agricultural appropriaton. In this discussion, erosion control practices are grouped as conservation tillage, which reduces sheet and rill erosion, and other practices which reduce slope length and runoff contouring, contour strip cropping and terraces. Analysis of the dynamics of the individual species revealed that the main mechanism explaining the strong effects of plant species diversity on soil erosion is the compensation or insurance effect, that is, the capacity of. Soil erosion depletes soil productivity, but the relationship between erosion and productivity is not well defined 63, 67,80, 83, 99, 100. Climate the two most important climatic factors having a direct effect on erosion are. Neither low intensity use nor high fertility amendments restored the soil to its original production potential after being damaged by erosion. Therefore, to calculate r factor, another method, which uses an equation that has been. Significant wind erosion occurs when strong winds blow over lighttextured soils that have been heavily grazed during periods of. But did you know that soil erosion also can seriously impair crop productivity.
Pdf effects of surface rock fragment characteristics on. The negative impacts of soil erosion due to inappropriate land management have become. Soil erosion food and agriculture organization of the united. The causes and effects of soil erosion from agriculture.
Furthermore, the link between soil erosion and affected water uses is not well defined. The process involves the loosening of the soil particles, blowing or washing away of the soil particles, and either ends up in the valley and faraway lands or washed away to the oceans by rivers and streams. An assessment of the global impact of 21st century land use change. The erosion of soil is one of several natural and human threats to sustained soil productivity, which may become irreversible if not mitigated. Erosion also reduces productivity through nonuniform removal of soil within a field.
K soil erodibility l length of slope s slope steepness c cover practice p support practice a soil loss in. Effects of soil erosion on soil properties as related to. Below are some of the major effects of soil erosion on the soil. This study is the first known attempt at estimating national offsite benefits from reducing soil erosion this report demonstrates how the offsite benefits from national soil erosion. Soil compaction, low organic matter, loss of soil structure, poor internal drainage, salinisation and soil acidity problems are other serious soil degradation conditions that can accelerate the soil erosion process. For most areas of iowa, the loss of 1 inch per acre of.
Its effects can be seen directly in the location where erosion takes place, known as onsite effects, and at the site where the eroded soil deposits offsite. In many cases, erosion is the first step that starts the irreversible transformation of the landscape into the barren desert. In north carolina its against the law any time an acre or more of land is cleared for commercial, residential, industrial or road construction purposes, a state or local government approved erosion control plan is. Effects of erosion control practices on nutrient loss. This equation provides an estimate of the soil loss rate in tonshectareyear.
The process of erosion usually takes place on the surface of soil, rock, or dissolved material from one location on the earths crust and with the help of the wind or water flow, it gets to settle down at another location. Effects of surface rock fragment characteristics on interrill runoff and erosion of a silty loam soil. It is also recognised as the most useful single indicator of soil quality soil carbon initiative 2011. The process may be natural or accelerated by human activity. Land degradation soil degradation is the decline in soil quality caused by its improper use, usually for agricultural, pastoral, industrial or urban purposes. In agriculture, soil erosion refers to the wearing away of a fields topsoil by the natural physical forces of water. The influence of land use and vege tation changes on soil erosion is highly variable and depends on the density of vegetation cover and vegetation morphology 6. It encompasses physical soil erosion, chemical salinity and alkalinity, pollution and biological deterioration pollution and.
Soil erosion is one of the most serious environmental and public health problems facing human. The spectacular episodes of erosion, such as the soil blowing on the great plains of the. Poor decisions can easily result in serious damage to soil. Soil erosion soil erosion is the washing or blowing away by wind or water of the top layer of soil dirt. The major effects of soil pollution on agriculture are. An offsite effect of downstream movement of sediment, causing flooding and the silting up of reservoirs.
Until the relationship is ade quately developed, selecting management strategies to maximize longterm crop pro duction will be impossible. Water erosion water erosion results from the removal of soil material by flowing water. Loss of plant species diversity reduces soil erosion. Land use humans play a major role in soil erosion through their use and abuse of natural resources, examples are deforestation, grazing, faulty farming systems, high crop intensity, housing construction, mining etc. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice glaciers, snow, air wind, plants, animals, and humans. The conventional wisdom has been to assume that surface roughness increases the resistance. T value tolerable erosion equilibrium between soil gains and losses. Soil organic carbon soc and its importance for soil quality soil organic carbon is the major component approximately 58% of soil organic matter and plays a vital role in agricultural production and in a range of other soil functions. Soil erosion is a process that involves the wearing away of the topsoil. Four natural laws of grazing management keep down the shoot, kill the root. Erosion also leaves large holes in the earth, which can weaken buildings and even cause them to collapse. Soil productivity is the capacity of a soil, in its normal environ ment, to produce a particular plant or. Universal soil erosion equation for questions 17, determine what the rate of soil erosion will be without factoring in sustainability measures for two different sites in jordan. Soil erosion food and agriculture organization of the united nations.
Soil erosion under different rainfall intensities, surface. Most agriculture activities, especially on sloping landscapes, increase the potential for soil erosion. The erosion had taken place 60 years prior to the study and the soil was in a very high fertility state, indicating that the effects of erosion are longlasting. In this publication, we focus our attention on concepts surrounding waterinduced soil erosion.
Land degradation, soil erosion and soil conservation pmf ias. Assessing soil erosion although soil erosion has been taking place very slowly in natural ecosystems throughout geologic time, its cumulative impacts on soil quality over billions of years have been significant. However, there are practices that can be undertaken to reduce human effects. Title page abstract introduction conclusions references tables figures j i j i back close full screen esc printerfriendly version interactive discussion abstract soil erosion is the main driver of land degradation in ethiopia, and in the whole region of east africa. Soil erosion is affected by many factors, among them topographic position of slope, vegetation and soil type have a momentous role on erosional behavior of soil morgan, 1986. Sheet erosion occurs when the entire surface of a field is gradually eroded in more or less uniform way. Soil erosion is an extremely dynamic and complicated process. Of those, the role of surface roughness in soil erosion is perhaps one of the most vexing problems. Lyles 1975 suggested that effects of wind erosion on crop production might be determined by relating top soil thickness or topsoil removal excluding fertilizer effects to crop yield table 1, then computing the potential average annual soil loss using a wind erosion. In the iowa cooperative soil survey program, erosion classes are defined quantitatively. The soil material is suspended in runoff water and carried away. Natural erosion has sculptured landforms on the uplands and built landforms on the lowlands. Soil erosion is a major environmental issue because it can lead to water pollution. Between 1982 and 2003, total soil erosion dropped from an estimate of.
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