基于GIS的雅安市土地生产潜力研究

以国产MAPGIS6．0软件为平台，对雅安市1：25万地形图、土地利用现状图、土壤图数字化叠加处理，生成16032个土地生产潜力评价单元，应用“机制法”计算土地生产潜力．研究表明：（1）雅安市大部分处于我国东部三等光温四级气候生产潜力西区，土地每年自然生产潜力在7843-17335kg／（hm^2）之间；（2）全市土地自然生产力水平为中等偏上，中低产田土占71．28％；（3）全市土地增产潜力平均为23．53％．区域潜在生产力差异的制约因素主要为土壤，次为水分；土壤限制因素为有机质、全氮，其次为速效磷和土壤质地．

Study on the Potential Productivity of Yaan City in GIS Environment

The main agriculture-resourse databases of Yaan city which included spatial databases and attribute databases was done, based on Geographic Information System.16032 evaluation units of the potential land productivity were overlaid out.By using the mechamism methodology and computing models,Yaan city's land productive potentiality was computed according to synthetic index of land productivity evaluation that was taken as soil effective coefficient.Result of research indicated that:(a)Siol effective coefficient changed from (0.3047) to 0.8550,and there is medium-low yield farmland of 71.28 percent. (b)Land natural productivity increased from 7843 kg/(hm~2)to 17335 kg/(hm~2),and the mean rate of enhancing yield is 23.53 percent in this region.(c)There are many facters that have been influencing soil effective coefficient such as soil organic matter,total nitrogen,effective phosphine and soil texture.The main attenuation result of land productivity is soil ,and next to water.