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2006-11-06 01:47:11 · 7 answers · asked by -Adri♥; 3 in Science & Mathematics Earth Sciences & Geology

7 answers

What causes erosion to be severe in some areas and minor elsewhere is a combination of many factors, including the amount and intensity of precipitation, the texture of the soil, the gradient of the slope, ground cover (from vegetation, rocks, etc.) and land use. The first factor, rain, is the agent for erosion, but the degree of erosion is governed by other factors.

The first three factors can remain fairly constant over time. In general, given the same kind of vegetative cover, you expect areas with high-intensity precipitation, sandy or silty soils and steep slopes to be the most erosive. Soils with a greater proportion of clay that receive less intense precipitation and are on gentle slopes tend to erode less. But here, the impact of atmospheric sodium on erodibility of clay should be considered.

The factor that is most subject to change is the amount and type of ground cover. When fires burn an area or when vegetation is removed as part of timber operations or building a house or a road, the susceptibility of the soil to erosion is greatly increased.

Roads are especially likely to cause increased rates of erosion because, in addition to removing ground cover, they can significantly change drainage patterns. A road that has a lot of rock and one that is "hydrologically invisible" (that gets the water off the road as quickly as possible, mimicking natural drainage patterns) has the best chance of not causing increased erosion.

Understandably, many human activities remove vegetation from an area, making the soil easily eroded. Logging and heavy grazing can reduce vegetation enough to increase erosion. Changes in the kind of vegetation in an area can also effect erosion rates. Different kinds of vegetation effect infiltration rates of rain into the soil. Forested areas have higher infiltration rates, so precipitation will result in less surface runoff, which erodes. Instead much of the water will go in subsurface flows, which are generally less erosive. Leaf litter and low shrubs are an important part of the high infiltration rates of forested systems, the removal of which can increase erosion rates. Leaf litter also shelters the soil from the impact of falling raindrops, which is a significant agent of erosion. Vegetation can also change the speed of surface runoff flows, so grasses and shrubs can also be instrumental in this aspect.

One of the main causes of erosive soil loss in the year 2006 is the result of slash and burn treatment of tropical forests. When the total ground surface is stripped of vegetation and then seared of all living organisms, the upper soils are vulnerable to both wind and water erosion. In a number of regions of the earth, entire sectors of a country have been rendered unproductive. For example, on the Madagascar high central plateau, comprising approximately ten percent of that country's land area, virtually the entire landscape is sterile of vegetation, with gully erosive furrows typically in excess of 50 meters deep and one kilometer wide. Shifting cultivation is a farming system which sometimes incorporates the slash and burn method in some regions of the world.

When land is overused by animal activities (including humans), there can be mechanical erosion and also removal of vegetation leading to erosion. In the case of the animal kingdom, this effect would become material primarily with very large animal herds stampeding such as the Blue Wildebeest on the Serengeti plain. Even in this case there are broader material benefits to the ecosystem, such as continuing the survival of grasslands, that are indigenous to this region. This effect may be viewed as anomalous or a problem only when there is a significant imbalance or overpopulation of one species.

Bank erosion started by four wheeler all-terrain vehicles, Yauhanna, South CarolinaIn the case of human use, the effects are also generally linked to overpopulation. For when large numbers of hikers use trails or extensive off road vehicle use occurs, erosive effects often follow, arising from vegetation removal and furrowing of foot traffic and off road vehicle tires. These effects can also accumulate from a variety of outdoor human activities, again simply arising from too many people using a finite land resource.

One of the most serious and long-running water erosion problems worldwide is in the People's Republic of China, on the middle reaches of the Yellow River and the upper reaches of the Yangtze River. From the Yellow River, over 1.6 billion tons of sediment flow each year into the ocean. The sediment originates primarily from water erosion in the Loess Plateau region of northwest China

2006-11-06 05:28:52 · answer #1 · answered by Geo06 5 · 1 0

Erosion can be caused by the action of water traveling through or over the soil or wind caused by blowing soil or sand from one location to another. Some experts also include gravity as a cause of erosion which can occur as a landslide or a sinkhole.

2006-11-06 04:17:44 · answer #2 · answered by quickgirl 2 · 0 0

yeah, it causes those things because global warming makes the soil wet and sometimes it results to forest fires! when the soil is dry, it may not be able to hold off the running water and erosion could be inevitable. desertification is not directly caused by global warming but somehow, it contributes to desertification.

2016-05-22 03:40:26 · answer #3 · answered by Anonymous · 0 0

Once cause is man & animals removing vegetation or altering the landscape so that water and wind can wear away at it. The ocean and rivers do it all on their own.

2006-11-06 01:55:03 · answer #4 · answered by Kacky 7 · 0 0

Wind, Rain, (Water in general) Including Ocean waves, and tide changes.

2006-11-06 01:49:12 · answer #5 · answered by Terry B 3 · 0 0

wron , wrong, wrong!!!
a)running waters
b)wind
c)Glaciers
d)gravity

2006-11-06 06:55:42 · answer #6 · answered by Anonymous · 0 0

IT CAN BE BY WATER ,WIND

2006-11-06 01:50:29 · answer #7 · answered by Anonymous · 0 0

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