DEGRADACIÓN POR EROSIÓN HÍDRICA Erosión Hídrica ¿QUE ES? Bibliografía %C3%B3n_h%C3%. EROSION “Erosion es un proceso de movilización y transporte de partículas por agentes erosivos.” Ellison, Agentes erosivos Impacto de gotas de lluvia. La erosion hidrica de los suelos. Causas y remedios. D’Onofrio, G. Lietaert, F. Perez, C. FAO, Rome (Italy). Direccion de Fomento de Tierras y AguasMinisterio .
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Los botones se encuentran debajo. Detachment adds sediment to the sediment hidrifa. Sediment load is the amount of soil being transported. Deposition is the transfer of sediment from the sediment load to the soil surface. Deposition causes sediment load to decreases and sediment to accumulate on the soil surface.
Other procedures must be used to estimate the other types of erosion. Ephemeral gullies reoccur in the same location, rills are parallel and generally do not reoccur in the same location. The dashed lines on the left show the RUSLE area that is hidfica in the upper right hand corner of the screen and the dashed line on the left side represents a subwatershed divide for a the two concentrated flow watersheds.
Soil loss is the net mass of sediment removed from a particular portion of the slope. In this simple uniform slope, sediment yield, which is the amount of sediment delivered to the end hifrica the slope equals soil loss. If deposition, like the deposition that occurs on concave slopes had occurred, sediment drosion would have been less than soil loss. Soil loss is expressed in unit of mass divided by the area that produced the soil loss.
Some soils are naturally more erodible than are other soils. Steep and long slopes produce more erosion than do short and flat slopes.
Land use has a huge effect on erosion. Exposing the soil to raindrop and surface runoff dramatically increases erosion. With the exception of the interaction between the R factor and the C factor, not interaction between the USLE factors were considered. The temporal scale used in computing the C factor was a crop stage period over which cover-management conditions were assumed to be represented by an average value for the period. The length of crop stage periods typically ranged from a few days, like the rough plowed period in the spring, to a few months, like the after harvest period over the late fall, winter, and early spring.
Also, the temporal time scale used in RUSLE1 was half month, and less if an operation occurred within a half month. The proper mathematical procedure is to compute a daily value for each factor, compute a daily soil loss value, and add up the daily values to obtain a value for rotation.
However, ls can be changed by installing terraces.
Erosión hídrica del suelo estimada para 99 cuencas uruguayas
On severely disturbed areas, both soil and topography can be changed. The most important consideration in conservation planning and the factor that has the single greatest effect on soil loss is land use, management, and the use of supporting practices like contouring. C also affects soil by changes in organic matter, random roughness and consolidation. Erosivity has two parts. The inherent yidrica determined by the rainfall at a location and the infiltration of the soil based on inherent soil properties.
The other part of erosivity is the part that management can change such as changes in infiltration that affects rate and amount of runoff and the present ersoion material that reduces the forces applied to the soil.
Erodibility is a measure of the susceptibility inverse of hdrica of the soil to erosion.
Erodibility has two parts, the inherent erodibility of the soil and the part of the erodibility that can be influenced by management. Erosivity is a function of climate and management. If transport capacity exceeds sediment load, sediment load will be determined by the amount of sediment made available by detachment.
If sediment load exceeds the amount of sediment produced by detachment, deposition occurs. If the sediment load exceeds transport capacity because of a decrease in transport capacity, deposition occurs which reduces sediment load. Deposition is a selective process where the coarse particles are deposited leaving the hidirca load enriched in fines. In this illustration, local deposition occurs on the very flat portion of the hillslope because interrill erosion produces more sediment than the flow can transport.
Deposition occurs on the lower end of the slope because of a decrease in transport capacity because of a flattening of the slope. Deposition begins to occur where transport capacity equals sediment load. Deposition does not necessarily begin to occur just where transport capacity begins to decease. The strip causes an abrupt decrease in transports capacity at the upper edge of the strip.
After the abrupt decrease, transport capacity increases within the strip. Deposition occurs because transport capacity erosioj to less than sediment load. If the strip is sufficiently wide, deposition will end within the strip where sediment load becomes equal to transport capacity.
The linear relationship between erodibility and soil erodibility allow simple mathematical approaches to integrate the variables over time. Climate is about times more erosive in New Orleans than in Las Vegas. The K value that is used if for the soil fines, but the influence of rock fragments in the soil profile should be considered in setting K values.
The effects of rock fragments on the soil surface is considered in the cover-management computations. Do not use a K value that has been adjusted for rock fragments on the soil surface because use of such an adjusted K value can cause a major mathematical error in RUSLE2.
Even though the hillslope is non-uniform, a uniform hillslope is often assumed in RUSLE2 to compute soil loss on the upper eroding portion of the hillslope. Such as approach is often satisfactory for most conservation planning. However, in some cases like concave: Even though deposition occurs on the midpart of this hillslope, the entire hillslope length has to be considered because of the origin of the runoff that flows over the lower portion.
RUSLE2 can be used to compute soil loss, deposition, and deposition for each of these slope shapes by dividing the slope into segments. These factors are for cover-management and supporting practices.
La erosion hidrica de los suelos. Causas y remedios
Referring to supporting practices as conservation practices is improper. No-till is a wonderful conservation practice that works entirely though cover-management hidricw. This deposition is remote deposition because it occurs some distance from where the sediment was detached. Soil loss also occurs at several locations on the slope. Even though deposition occurs, the surface runoff continue through the depositional area. Soil loss on the lower part of the slope depends on runoff that originated from the very upper end of the slope.
Two distinct rates of soil loss occur on this slope. Soil loss occurs on the inter-terrace interval. Soil loss on the inter-terrace interval is less than soil loss without the terraces because terraces shorten up the slope length. Runoff on the lower inter-terrace interval originates at the next terrace upslope, not from the very erision of the hillslope.
The deposition that occurs in the terrace channels is remote deposition because the location of the deposition is some distance from where the sediment was detached.
Also, the deposition is concentrated in a much smaller area than the area that produced the sediment. Spacing varies with gradient terraces because of nonuniform topography. Generally discharge into grassed waterway to get runoff down slope without causing ephemeral gully erosion Grade nonuniform along parallel terraces.
Have to be careful to avoid grade along parallel terraces being too steep. Sediment basins usually used in conjunction with parallel terraces. Typically discharge into underground tile line. Main purpose of both systems is runoff management to control excessive rill erosion and especially ephemeral gully erosion.