基于GIS的重庆市耕地质量评价模型的建立与检验

借助GIS空间数据获取、分析与管理能力，基于农用地分等方法的应用和改进，建立了重庆市耕地质量评价模型。评价模型通过分功能模块从机理上实现评价质量控制，就光温/气候潜力加和算法，采用以能值为基础确定标准产量折算系数 ，引入光温潜力协调系数 ；就自然质量分模型，指标区之间因素－分级－分值进行了统一，但保留了因素权重的区域差异性。采用2004-2005年重庆市分区县统计的平均粮食播面单产对自然质量等和利用等进行独立检验，线性相关系数分别达83％和87％，相关性显著。研究得出结论，评价模型有效实现了重庆市耕地质量评价区域间的可比性。

Yuan Tianfeng1, 3, Qiu Daochi1, Xie Deti1, Hu Yuqing2, Wei Chaofu1

With the aid of MapGIS capability in obtaining, analyzing and managing space data, based on the methodology of Agricultural Land Classification applied and ameliorated, Cultivated Land Quality Evaluation Model of Chongqing was built up, which included Physical Quality Grade Index model and Use Grade Index model. The object evaluation was the Cultivated Land updated to end of 2003 in 39 boroughs or counties of Chongqing, which total acreage was 2347627.48 hm2, including 142319 evaluation units obtained based on 1: 50000 land use maps of every boroughs or counties. Evaluation Model realized control of evaluation quality from mechanism by differential function module, so as to reach comparability among factor districts or among standard farming systems. (1) To addition of Photo-Thermal Productivity Index, converting standard yield coefficient was determined based on energy value, and harmonizing Photo-Thermal Productivity coefficient was introduced. (2) To Physical Quality Cent Model, factor-grading-value of cultivated land quality evaluation among factor districts was unified, but otherness of factors’ weight was kept among factor districts, which embodied the unification of commonness and individuality among districts. In order to checkout the rationality of the methodology, statistical average crop yield of per unit of seed-acreage of boroughs or counties in Chongqing from 2004 to 2005, was adopted to checkout average Physical Quality Grade and Use Grade. Result shows, linear correlative coefficients are respectively 83% and 87%, that is, both correlativity marked and correlativity of Use Grade are appreciably higher than that of Physical Quality Grade. Conclusion is drawn: the Evaluation Model effectively realizes the comparability of cultivated land quality evaluation among inner regions in Chongqing.