Suitability Evaluation Of Cultivated Land Reserve Resources Development Based On Ecological Security In Zichang City

China’s cultivated land area is 1,432,960 square kilometers,ranking third in the world,but due to the rapid development of urbanization or industrialization and the agricultural structure adjustment in recent years,the area of cultivated land is decreasing year by year.In addition,overexploitation of land resources,desertification,soil erosion and other environmental problems also seriously threaten the protection of cultivated land.To solve this problem,the Chinese government has taken a series of measures to strengthen the protection of cultivated land.In this paper,Zichang City is taken as the research area,GIS spatial analysis method,limiting factor method,comprehensive index method and other research methods are used to evaluate the suitability of cultivated land reserve resources in Zichang City based on ecological security,and design the technical route of the suitability evaluation of cultivated land reserve resources in Zichang City.Secondly,data such as the natural conditions and ecological environment of Zichang City are collected.In addition,the types of cultivated land use in the study area,the influencing factors of cultivated land,the status quo of cultivated land use and the existing problems of cultivated land are explained.Under such a background,the research content of this paper are as follows:(1)Based on the data of the third National land survey in Zichang City,this paper analyzed the current situation of cultivated land reserve resources by combining the limiting factor method,comprehensive index method and hierarchical analysis method,and evaluated the suitability of cultivated land reserve resources development based on ecological security;It was determined that the land map spot in the land use status data should be taken as the minimum evaluation unit and bare land and other grassland should be taken as the evaluation object of cultivated land reserve resources.Based on the limiting factor method,this study screened the factors that had influence on the suitability of cultivated land reserve resources in the study area.The index system was constructed from three aspects of ecological support,natural suitability and farming economy,and 11 specific evaluation indexes were determined under the three factor levels to evaluate the existing cultivated land reserve resources.(2)The evaluation indexes of the ecological support layer include: ecological rigidity,river buffer,geological disaster and ecological stability;The evaluation indexes of natural suitability layer include slope,soil texture,soil thickness,soil p H value and irrigation conditions.Tillage economy layer index includes: tillage access and tillage contiguity.The cultivated land reserve resources in the study area are in the range of the first and second buffer zones of river surface,far away from the geological disaster points,in the range of safe cultivation,and the whole is close to the ecological land space.(3)This paper comprehensively evaluates the suitability of cultivated land reserve resources development in Zichang City and obtains the research results of the suitability of cultivated land reserve resources development in Zichang City.Based on the premise of ecological security,the calculation results after considering the suitability of natural development and the economy of cultivation showed that most of the reserve cultivated land resources in Zichang City were in the range of general suitability and reluctant suitability of development,and the key development objects were concentrated in Yangjiayuanze Town,Yujiaping town,Yujiwan Town and Lijiacha town in the northwest.These towns are distributed with other grasslands of smaller slope,adjacent to the reservoir and road with an area of more than 20 hectares.Other grasslands are adjacent to the existing cultivated land or ecological land,and can play a synergistic ecological benefit in space.Other reserve cultivated land resources with scattered distribution,broken form and far away from roads can be included in the scope of ecological land as a "stepping stone" and "rest point" connecting the ecological corridor of Zichang City and the important ecological source area,so as to consolidate the stability of the ecological system in the study area.