A Study On Fuzzy Evaluation Of Grassland Ecological Security Based On GIS

Informationization is nowadays the distinct characteristic and main trend of the social development. Represented by "3S" technology modern geographical information technology becomes important technical support of the issue in geography and ecological environment at present already. As one of the "3S" technology, GIS becomes mature and perfect day by day through the development, popularization and application for more than 30 years, and especially make a lot of important achievements attracting people's attention widely after led into fields of ecological environment study.In recent years, the impact on the mankind survives and national safety of ecological environment is more and more obvious. In the world, the Eco-crisis has already become one of the most basic factors of the contradiction and conflict between countries and regions. Therefore, ecological security as a non-traditional security must be located at the same position as political security, military security, economic security, scientific security and so on. As the foundation of another security, it extended the notion of national security. The main countries in the world have offered especial attention to ecological security study, the research on which increased day by day too. Seen from current domestic ecological environment situation and international competition, our country's ecological security situation of early 21st century is very severe, the study about ecological security has been already extremely urgent.Because of important strategic meaning of ecological security and GIS becoming mature, the relevant studies of ecological security based on GIS have wide prospect. With this background, the author, aiming for grassland ecosystem, probes into basic theories of ecological security and relevant problems about evaluation of grassland ecological security based on GIS.This paper expounds the meaning of ecological security, including the international and domestic discussion, the characteristic and research meaning of ecological security, and then expounds the definition of ecological security evaluation and research development on it. On the basis of this, the author puts forward the definition of grassland ecological security, named that within the range of specific space and time, the inherent structures, outside show and function of grassland ecosystem lies in a state that under existing natural environmentpressure and social economic pressure and the mankind's positive responses, support and influence that its ecological service can offer to mankind's surviving and continuous development of society and economy make human life, production, health and development being in security; at last expounds the principle of grassland ecological security evaluation and introduces some relevant evaluation methods.In the part of the standard and index system of grassland ecological security evaluation, the author introduces selected principle, founded methods, sources of evaluation criterion and the principle that structures the index system of grassland ecological security evaluation, designs the concept frame of grassland ecological security evaluation learning from that of Driving force -PSR, and structures the index system of hierarchical structure of grassland ecological security evaluation according to the characteristic of grassland ecosystem and social and economic development of grassland.In the theoretical research on fuzzy evaluation of grassland ecological security based on GIS, the author recommends the thinking and the technological flow of it; puts emphasis on the model of fuzzy evaluation of grassland ecological security and the realization of visualization expression, establishes the model of fuzzy evaluation of grassland ecological security and discusses 2D visualization expression in the evaluation result and the index data, the realization way of evaluation courses. In the design of the database of fuzzy evaluation of grassland ecological security, the author describes the organization and management of the dat...