Analasis Of Eco-enviromental Vulnerability And Assessment Of Ecologial Carrying Capacity In Hulunbeir Steppe

Resent years, because of the influences of nature factors and human activities, the eco-environment of the Hulunbeier steppe was gradually worsen. Evaluation of eco-environmental vulnerability and regional ecological carrying capacity had significently importance and realistic meaning for the regional sustainable development. In this study, two evaluation models of eco-environment vulnerablility and ecological carrying capacity were constructed based on the vector datus and statistic datus. Results are as following:(1) The causes of eco-environmental vulnerability of grassland were the outcomes of interaction of nature and the human beings. Among these reasons, the loose soil texture, which was formed in the fluviolacustrine sediment during Quaternary, establish the physical ground. Then harsh nature condition and fluctuant climate lead this area to a sensitive region. Addition, unreasonable mankind's activities, such as over-cutting forest, over-grazing grassland, reclamation and so all accelerated the process of vulnerability.(2) In order to analyze eco-environmental vulnerability, geographical information system (G1S) technologies were adopted, an eco-environmental evaluation model was developed using spatial principle component analysis method. The spatial principle component analysis, using coefficients of linear correlation offers the possibility to weight the contribution of factors. This method not only reduced the subjective and arbitrary, but also eliminated the overlap between the evaluation factors. GIS as a powerful tool for ecological environment assessment, cannot only supplied spatial data analysis platform, but also possessed calculation function. In this study, all principle components were extracted to improve the precision.(3) In general, Eco-environmental state of Chenbaerhu Banner was belonged to relatively slight vulnerable level. Eco-environment vulnerability in study area presented distinct geographical horizontal-belt distribution. From northeast to southwest the eco-environment was gradually deteriorating with the changes of natural conditions, climatic factors, exploitation of natural resources. Heavy vulnerable level distributed in two sides of the Hailar River and Argun River.(4) Grassland degradation made a greater contribution to the eco-environmental vulnerability, but it was not the determining factor. And the eco-environmental vulnerabilituy was dicided by the factors of topography,climate conditions, soil characters and vegetations and so all, so the degree of eco-environmental vulnerability were not corresponding to that of grassland detradation.(5) It is Ecological carrying capacity evaluation model was developed using the human carrying capacity and the livestock carrying capacity and the rate of population accommodation and the rate of livestock accommodation as indicators. It not only reasonably evaluated the status of exploitations of grass, but also estimated the level of regional sustainable development. Meanwhile, the indexes of available grass were introduced into the ecological carrying capacity evaluation model, considering the eco-environmental vulnerability.(6) with the degrees of eco-environmental vulnerability increased, the levels of reginoal livestocks carrying capacities were increased.while human carrying capacity had not obvious correlation to the eco-environmental vulnerability due to it was influnced by soscial fators,ecnomic factors and natural factors and so all.(7) chenbaerhu banner included eight towns all together, livestocks had existed overloading in five towns of them, while the population did not appeared over carrying, exept of baorixile town and bayankuren town. So deterioration of the ecological environment was mainly due to the fast development of livestocks.