Research On Demarcate Method Of Basic Farmland Based On RS And GIS

Arable land is a precious and scarce resource as well as a significant foundation of the survival and development of human race. As a part of arable land, especially the part with high yield and high quality, capital farmland is the guarantee of our nation’s food security. It has direct impact on China’s economic development and social stability, and the strengthening of the protection of capital farmland is a colossal major issue which relates to the benefit of the people’s livelihood, while the key issue of the protection of capital farmland is to designate capital farmland scientifically and rationally. In the process of designation, the backward skill and administrative methods as well as the insufficient consideration on the current situation, quality, and spatial distribution of farmland has led to a number of questions in the means of designation of capital farmland. The distinct performance of which is the low efficiency in the designation of capital farmland, the irrational operation on the adding and cutting of land patches on the basis of planning capital farmland preservation area protective areas. and the ultimately designated capital farmland are found out mixed with other land types, of irrational distribution, of low quality and so on.In this dissertation, the intelligent designation of capital farmland and scientific storage management serve as the entry points, the case of Donghai County in Lianyungang combined with theories relevant to the designation and management of capital farmland, a complete delineation on scientific demarcating processes of capital farmland is built. This dissertation also studied the methods of designation on the adding and cutting of capital farmland on the basis of RS and GIS, and built a database on the designation of capital farmland as well as designed a management system. The scientific delineation of capital farmland and subsequent information management is expected to be achieved through this study.The main conclusions of this dissertation are as follows:(1) On the basis of defect from basic farmland demarcated by traditional method, this research has built a complete delineation on scientific demarcating processes of capital farmland based on RS and GIS technology. Arable land is extracted from the high-resolution remote sensing image, and suspected non-arable land is confirmed while overlying of basic farmland conservation area, cut land patches are confirmed after field investigation of the suspected non-arable land. Land qualities affection factors are quantitatively evaluated by methods of buffer analysis and overlay analysis from GIS spatial analysis, which comes out the evaluation result of cultivated land quality grade. Adding land patches are selected after the comparison of land use planning map, which are high quality cultivated land outside the range of basic farmland conservation area.(2) With the method of combination on RS and GIS, patches cut and added for basic farmland demarcated are more scientific and reasonable, which solves problems with traditional method. Land patches demarcated from the high-resolution remote sensing image are more accurate and time effective than current land use map, which makes it easier for finding suspected non-arable land. Using GIS method to quantitatively evaluate factor system of arable land quality, has confirmed the key elements such as quality level and joint degree.(3) This research takes Donghai County in Jiangsu Province as the typical case area, with the method of combination of RS and GIS, demarcate the patches of basic farmland successfully. This research takes high-resolution remote sensing image, present land-use map and planning land-use map as the data source, according to the method of object-oriented classification, using FX tool from ENVI EX expansion model finish the arable land exacting work. The evaluation index system of arable land is consisted of four levels:the natural conditions, the soil conditions, the farmland infrastructure conditions and location conditions. On the basis of extracting current object stands for the index system, using ArcGIS as a tool for index quantification by buffer analysis and spatial overlay methods. The result of adding patch is considered by grading and appraisal to the quality of arable land, which comes out after the quantitative evaluate of the factor by GIS spatial method.