Landscape Structure Of Meihekou City And The Impact Of On Erosion

The human's ability to exploit and utilize the natural resources is increasing with thehigh-developed productivity and drastic conflict between the limit land resources and theincreasing population. Under the situation of poor environmental protection realization andthe lagged harness, the ecological environment is becoming worse.Soil erosion is the result of people's unscientific land use. Based on landscape ecologytheory, the ecological pattern of land use and soil erosion in Meihekou City was studiedquantitatively in order to know and improve scientifically and fully the ecologicalenvironment in the study region.Using GIS software ARCVIEW3.3 landscape indices (Diversity Evenness DominanceFractal dimension and Isolation et.) were chosen to study the spatial patterns of the land useand soil erosion in Meihekou City. The results showed that: Methods and results of the studyare as follows:( 1 )This paper systematically decodes Meihekou City's landscape types in 2000, on thebase of remote sensing data. According to the analysis of the results of remote sensing imagedecoding, the region studied contains 9 types of landscapes, totally 3297 patches,1060 ofwhich are residential areas, which accounts for 1160, and moorlands the fewest. Forests takeup the largest area of 720.2km, followed by grasslands, arable lands, moorlands, rivers cityareas and bushes. In terms of area structure, forests, grasslands and arable lands are maintypes of landscapes in this region, occupying 89.14% of the total area, while residential areasaccount for 6.78%. As to average area of patches, forests and city areas take relatively largeparts, followed by arable lands. ( 2 )Though the calculation of canyon density, deducing the intensity of soil erosion,according to this and other influence factors, the region studied is divided into three parts----the hilly lands in the north and northeast, plain areas in the middle and lower mountainousareas in the south and the west. ( 3 )The theory of landscape ecology considers landscape pattern as the main reason forsoil and water loss on large scale. By computing landscape indices concerning landscapetypes, patch characters and comparing them among the three areas, the result indicates that:In the north and northeast hilly lands, the wood and grass coverage rate of the whole area islow, making the region the largest area that suffers the most serious soil and water loss. Asregards the plain areas in the middle, soil and water loss is intensified by frequent agriculturalactivities, large quantities of city and residential areas, causing much artificial disturbance. Asto the lower mountainous areas in the south and the west, the ecological situation is better, forthere are large areas of natural secondary forests and high rate of grassland coverage, withlittle artificial influence.( 4 )Based on the ecological pattern of land use and soil erosion in Meihekou City, somecountermeasures against the soil erosion were proposed guided by the landscape ecologytheory.