Study On The Cultivated Land Classification Of County In GIS Technique

This paper comprehensively expounds the purpose, significance, theoretical rudiment and methodology of agricultural land classification from history and present situation at home and abroad. The paper is according to"Regulation for Classifying Agricultural Land"issued by the Ministry of Land and Resources, and the past experiences on this issue is used as references. Based on the overall analysis of the landforms, climate, soil and farming system of Shaanxi, the author takes ZiChang county, Shaanxi as an example to study the agricultural land classification according to its unique charateristics. In the process of researching, data analyzing, investigation, quality and quantity analyzing combined with GIS technology are used as methonology.The author firstly sets forth the theories and techonologies of agricultural land classification, studies closely with factors and importance involved in land classification, and divides the area for classifying. Then, the author defines the potential productivity related with light, temperature and climate, the maximum productivity and the coefficient of productivity ratio. What's more, Delphi technique is applied for identifying products and editing the procedure of"appointed products—classifying factors—table of scoring regulations".Then, partial correlation analysis is used to analyze and prove each element. Finally, ZiChang county is taken as an example used to data collection, recording, editing, analysis and computerized calculation. On the basis of that, calculation and specific pictures making are done with the application of GIS technology.At the end of this paper, the author concludes that the natural rank of ZiChang is 3, 4, 5, and the natural rank index is distributed over [527.8634,969.3066]; the utilization level is at rank 3, 4, 5, 6, 7, and the utilization index is scattered between [264.9839,662.9124]; the economic rank is 2, 3, 4, and its index is between [109.0655,305.0822]. The study is resonable and reliable through the test of theories and practice. It has important thoretical and practical significance for relevant government departments to make policies on agricultural development, cultivated land exploitage, usage, regulation and protection, and the sustainable usage of the agricultural land.