The Main Effects and Solutions of Soil Erosion

Renfang(Alice) Liao

Academic Skills 300-1
Professor Smithwick

Aug 17, 2012

Introduction Soil erosion is a global issue troubling most of the countries. China ranked 129 among the 142 environmental suspensibility evaluated countries; one of the reasons is the serious soil erosion. 19% of China's land is affected by soil erosion, which is one of the highest rates (Liu& Diamond, 2005: 1181). The statistics are thought-provoking, and the effects of soil erosion are significant. In fact, soil erosion is a part of a vicious circle. Scientists and technicians around the world are working hard to find out the better and more efficient ways to monitor and control soil erosion. Soil erosion is a progress in which soil particles are carried away by force such as water ,wind and gravity. Water and wind erosion are the most important erosion types classified by the erosive agents (Toy, Foster, and Renard, 2002: 55). In this report, the vicious circle of soil erosion, reduction of vegetations and sediments in river is discussed. Among the technologies applied in soil management, the one suitable for local condition is the best.
Discussion
Soil Erosion and Vegetation Soil Erosion's effects on Vegetation Plants absorb what they need from soil with roots. The topsoil provides the best environment for plants' roots with loose structure, enough air, and rich organisms, but it is removed firstly through soil erosion (Plaster, 1992: 413 ). First, soil erosion takes away the nutritions such as Nitrogen, phosphorus, and Potassium, which are essential to plants' health. If any of the essential nutritions is lacked, the growth of plants is effected badly. For example, the colour of leaves will turn pale when Nitrogen is lacked. Secondly, the zone for roots is decreasing because the thick of topsoil becomes thinner, as the soil surfacing is lost. If the roos' zone keep decreasing, they cannot support the plants, nor can they absorb enough nutritions from the soil. Third, the loose structure is damaged, so the water-holing capacity of soil is also reduced. Water is important to all the creatures including plants, which keeps cells in shape and provides a stable environment for the chemical reactions proceeding every second inside a plant. Reduction of Plants Aggravate Soil Erosion The vegetations' leaves, limbs, trunks provide a natural protection for soil. "Bare soil is fully exposed to the erosive forces of raindrop impact and the scouring of running water"(Plaster,1992: 418). The roots of vegetations are dense and can be as long as several metres. They hold soil in place instead of being taken away by water or wind. Methods of Agriculture has Effects on Soil Erosion Data from global studies shows that the erosion rate of conventionally plowed fields are greater than the rates of soil production, erosion rates under native vegetation by 1-2 order's of magnitude. Soil production and erosion in hill slope areas gradually balance the geologic and climate factors' effects; however, the erosion of conventionally plowed fields are increased to a unsustainable level. The ways of irrigation also matter in soil erosion. The advanced technology such as drop irrigation is much more efficient traditional irrigation.
Soil Erosion and Rover Management
Soil Erosion Aggravates Sediments Plaster stated that the soil washed away by water erosion gradually settles down under the water, as the flow velocity slows down. As a result, soil becomes sediments in all kinds of areas such as rivers, lakes and harbors. Sediments also reduces the flood storage of rivers, resulting in the increased possibility of floods (1992: 414). The part of river which can be used for shipping is shortened, too.
Soil Erosion has Effects on Water Quality
The eroded soil stays in water as colloid or suspended particles before suttle down. As a result, clear water becomes turbid liquid and the light in water is reduced. The photosynthesis of the aquatic plants are also affected even obstructed. Some chemical substances are washed away with soil, such as pesticide and chemical fertilizers. Some of them are poison, while some others may break the nutrition balance in water. Red tides is an exploding accumulation of some algae, when the environment is suitable, especially when the nutrient is rich in water. [pic]

The bar graph above shows the average annual number of red tides in
Chinese seas. Before 1990s, the number grew quite slowly. The number increased greatly in 1990s, and then rocketed to nearly 90 in2000s.
Solution
New monitor methods and evaluation models

New agriculture methods and adjustment to local condition

References

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Montgomery, D. R. (2007). Soil Erosion and Agricultural Sustainability. Proceedings of the National Academy of Sciences of the United States of America, 104(33),13268 -13272.

Nebel, B. J., Wright, R. T., (1998). Environmental science : the way the world works (6th ed.). Upper Saddle River, NJ : Prentice Hall.

Plaster, E. J. (1997). Soil science & management (3rd ed. ). Albany : Delmar Publishers.

Toy, Terrence J., Foster, G. R., Renard, K. G. (2002). Soil erosion : processes, prediction, measurement, and control. New York : J. Wiley.

Zhao, Y., Pei, Y. S. (2010). A Study on Distributed Simulation of Soil Wind Erosion and Its Application to the Tuhaimajia River Basin. Procedia Environmental Sciences, 2, 1555-1568. doi: 10.1016/j.proenv.2010.10.168

Liu, J., Diamond, J., (2005). China's environment in a globalizing world . Nature 435(7046), 1179-1187.