近17年城镇用地扩展对粮食生产影响的定量评估研究--以江苏省常熟市为例

运用多源遥感数据，获得常熟市1984、1992、1999和2001年四个时期城镇建设用地状况矢量数据。利用土壤普查资料建立土壤空间和属性数据库。统计分析并借助水稻土生产力评价模型对17年来城镇建设用地扩展占用的水田生产力状况评价研究表明：1984～2001年的17年间，常熟市城镇建设用地扩展占用水田面积2438公顷，根据现有的生产管理水平估算，粮食年产量损失总量约2万t，城镇扩展损失水田以生产力水平中、高等级为主，损失水田平均产量达8160kg／hm^2。水稻土生产力指数模型(SPI)可以对常熟市水田土壤生产力进行合理地评价，可以用来估算在城镇建设用地扩展对水田土壤生产力和水稻产量造成的损失量。

Evaluating Loss of Rice Yield Caused by City Expansion in Recent 17 Years--A Case Study of Changshu City from 1984-2001

Using multi-source remote sensing data, four vector maps of expanding towns of Changshu City from 1984 to 2001 are acquired, and a soil database is constructed based on the Second Soil Survey of study area. By a concept soil productivity index (SPI) model combined with soil database, the loss of rice yield and paddy soil productivity caused by urban expansion are evaluated from 1984 to 2001. The model can be used to evaluate soil productivity and the yield of rice at certain management level. As a whole, the productivity of paddy soil is high in Changshu. The extending urban construction has invaded about 2,438 ha of paddy field among recent 17 years, which causes about 20,000 tons of the loss of rice at a management level today. The most of the cropland occupied by urban expanding has high or middle productivity. The loss of average yield of rice is about 8 160 kg/hm~2. The soil productivity index (SPI) model can be used to evaluate the distribution of paddy soil productivity and the loss of rice yield caused by urban expansion.