Gis And Rs Technology-based Regional Eco-environmental Sensitivity Evaluation

Given in the situation of development in society and improvement in technology, human beings have been affecting greatly in intensity and range of physicial environment. Therefore some problems of regional ecological environment have been going side by side broadenly and intensely.such as desentification, soil erosion, salinization and acid rain etc. Meanwhile, studies in the sensitivity of ecological environment of Geographical Informations System and remote sensing theory, GIS and RS are expanded from the limited applying area initially to now, which are coveting overtly all applying area related to space information, especially since the 1990s, The improvements in GIS and RS theory lead some powful softwares of commerce GIS to come into forth.These practical softwares promote the expanding of GIS in all application area. So, it is an urgency that the application of GIS and RS is used to the study of ecological enviroment.This thesis focuses on the heart of the ecological environment study—sensitivity evaluation .It takes the focal coutry town of "Three Gorges Reservoir Area -Feng Du country as an example", attempts to combine the GIS and RS into the sensitivity evaluation in the ecological environment in the aim of solving some problems in evaluation, such as the low efficiency, short precision and high costs in time and energy. If tries to make the sensitity evaluation in the ecological enviroment to achieve in combining all kinds of informations and sciences. On the basis of constructing a platform of ARCVIEW GIS, this thesis makes a model for GIS, and evaluates to the sensitivity of ecological environment.So this thesis tries to answer the following quests. (1) The theoretical basis for the foundation theory of environment evalus .the sensitivity evaluation of the regional ecological environoment. At first, this chapter gives the definition of GIS and RS then , if builts up two definition frame works,one is sensjtifivity evaluation of regional ecological environoment,which is taken from the combination of ecological environment system and stratification analysis,the other is abstracted from evaluation quota system.The two definition frameworks can give the theorectical direction for the ovderall sensitivity evaluation of the regional ecological environment and for the administrating practice in the ecological environment.(2). The study of the chart measure in the sensitivity evaluation of the regional ecological environment. Taking the experimental data as consideration, it takes the systematical study in the dialectical relations between the regional prameter; the chartmeasure, the visual effect of picture, data precision and the data amount charge and gives the data studying environment framework of the overall sensitivity evaluation in regional ecological environmental parameter.(3). Enlightened by the GIS space analysis technology, it overcomes some problems in the sensivity evaluation in the regional ecological environment, such as quantitative analysis for the soil erosion ,the sensitivity evaluation of the landslide, if solves some shortages of mas-calculation and the great amount of data,and tries to make the whole process to be stream line.(4)The sensitivity evaluation in the focal ecological elements based on analyzing the current condition of the regional ecological environment, this chapter takes several elements which is related closely to the ecological sensitivity. They are the regional soil erosion, the landslide sensitivity, acid subsiding which effect the sensitivity of the ecological system.And it tries to evaluate them from the model.(5)The study of evaluation model. Based on the analysis of current methods in evaluating relations between the environment and ecology, if builts up the optional overall evaluation model for the sensitivity of the regional ecological environment.this model can be applied in the synthetical evaluation and the chart of the sensitivity of the regional ecological environment.Genuine knowledge comes from pracice.the sensitivity evaluation classification of the regional ecological environment which is based on the GIS and RS theory,are more quick and efficient than the traditional evaluation in this rara.If combine it to a proper evaluating model,it can replace entirely the trational sensitivity evaluation method.As a result,it doesn't only rise the working efficience,improve the sensitivity evaluation of the ecological environment secientifcally and precisely,but also it can make a great progress in the sensitivity evaluation of the regional ecological environment for its model analysis,quantitative analysis and modernization.