基于RRM模型的三峡库区重庆开县消落区土地利用生态风险评价

以三峡库区重庆开县消落区为研究对象,基于风险度量的基本原理,在实地考察、历史资料考证和2007年遥感影像景观分类的基础上引入相对风险模型,将研究区划分为4个风险单元,并选取5种生境类型、5类风险源和3种生态受体,以此计算该地区不同风险小区土地利用的综合生态风险值,并依据生态风险值的高低划分为4级.研究结果表明,在消落区内,风险等级随着土地出露水面海拔高度的增加而加大,在海拔达到170m以上的消落区生态系统受到的伤害更大.作物种植等风险源对生物物种、生态系统等生态受体的作用是生态风险增大的主要原因,其中,生物物种受到的风险最大,其次为生态系统、景观格局.研究结果可为三峡库区的环境保护和生态风险管理决策提供科学依据.

Regional ecological risk assessment of land use in the flooding zone of the Three Gorges Reservoir area based on relative risk model

The relative risk model (RRM) is introduced on the basis of the basic principles of risk measurement and regional ecological risk assessment. We choose the fluctuating zone of Three Gorges Reservoir in Kai County as the research object, and analyze the historical data as well as the landscape classification based on remote sensing images of 2007. Moreover, we divide the project district into four risk units, and selecte five habitat types, four risk sources, three kinds of ecological receptors to calculate the comprehensive ecological risk value. Then, we divide the risk values into 4 risk grades. The results of the research detected: I. The land of the fluctuating area of the Kai County is mainly used as arable land, which contributes a lot to the economic development of that area, but faces with a relatively higher ecological risk. II. There is a larger amount of developed area, and accordingly, a relatively higher risk value exists resulting in high degree of risk. At an elevation of 170 meters above,the ecological system in flooding zone is hurt even more. In conclusion, based on the research of the Kai County, ecological risk management strategy of land use in fluctuating area has been proposed, aiming at providing a theoretical basis for evaluating land use ecological risks of fluctuating reservoir areas. Its exemplary role and practical significance are also of great importance.