| As one of the environmental problems in the world, soil erosion has receivedworldwide attention in recent years due to its effect on the sustainable development ofsociety and human survival. China is one of the country that has world’s most serioussoil erosion.This paper take the important commodity grain base of in DongliaoheBasin in Jilin province as the research area. Based on theories of soil erosion andlandscape ecology，With the aid of RS,GIS and other modern information processingtechnology to carry out research on rapid evaluation method of soil erosion inwatershed scale to assess soil erosion respectively under the1988,1998and2008.Onthis basis, the paper analysis the research area soil erosion spatial and temporalvariations in20years with the perspective of using landscape ecology. In this study itcan provide important theoretical basis and reference to decision comprehensivemanagement and the construction of ecological restoration of soil erosion.It mainly includes the following：1.Watershed soil erosion factor access and management of spatial data.Soil erosion in Dongliaohe Basin is influenced by the topography, vegetation,soil, rainfall and land use and other factors, this paper using remote sensing and GIStechnology,to extract the main factor affecting soil erosion, on this basis theevaluation of spatial database of soil erosion is established to provide the data foranalysis and evaluation of soil erosion.2.Soil erosion change analysis of spatio-temporal variation relationship as awholeAnalysis of change of soil erosion in1988,1998and2008，and the researchresults show that the research area soil erosion area showing trend which significantlyincreased rapidly at first and slowly decrease.Erosion decreased in different rate after1998,among this that the severe erosion rate of change of is the largest,which reaching46.36%. By means of transfer matrix can be learned in1998to2008major types oferosion are severe and extremely strong-strong; very strong-strong and medium-micro; strong and moderate, mild, moderate and mild-micro; micro； mild-micro-moderate; micro-mild-moderate, the characteristics of landscape erosion pattern of the research area tends to be low heterogeneity, low fragmentation andregularization.3.Sub basin of agriculture landscape pattern and soil erosionAccording to the evaluation results in1988,1998and2008the soil erosion inresearch area, study Agriculture of the relationship between landscape pattern and soilerosion in different time,demonstrate that research area experienced a degree offragmentation increases from1988to1998reduced to the2008changes, Areaweighted mean patch fractal dimension of this three year first becomes small after thesmall amplitude becomes larger, indicating that the human intervention is the mainreason of shape of patches in the research area than the overall rule. The Shannon’sdiversity index of sensitivity of landscape types can represent high, which meanslandscape heterogeneity, the negative correlation indicating that the index hassignificance in inhibition of erosion.4.Different background and different soil erosion in watershed areaBased on the landscape ecology to study soil erosion change of the research areain different conditions and different watershed partition based on the situation among20years. The region which at an altitude of250m,slope above8o-15oand that dryfield is the mainly types of land use is the main soil erosion zone of suffer high risk.the serious erosion area erosion tends to turn for the better since the treatment In1998,the governance of the forest and dry areas is the most prominent. At the same time ondifferent natural geographical districts of soil erosion are analyzed. The results showthat the upstream hilly areas of the most serious soil erosion, follows by the middlehilly area, middle hilly area is larger, while the downstream plain and hillock areaare no obvious. after governance of10years, from1998to2008, the status of soilerosion in hilly areas has improved, but still is the key area of soil and waterconservation. |
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