土壤生产力模型及其预测城镇扩展对粮食生产影响的研究

In the research project, expanded speed and distribution of urban land during in the period of 1984 - 1992 and 1992 - 2001 were acquired by interpretations of TM and SPOT satellite images in Suzhou, Wuxi and Changsu districts. A soil productivity model for rice field was established tentatively related on rice root growing by field experiments of testing of rice root and bio-weight, yield estimation of different type of soils in 2000 and 2001. Rice productivity losses caused by urban land expand was also estimated in this area during the two periods. Results shows that the root density (or root bio-weight) in the period of fringe differentiation is corrective to rice yield at 0.01 level, the minimum data set which affects the growth of root include organic matter, pH, total phosphor, soluble potassium and total pority. The urban land expanded was as 3 times as that in 1984 during the 17 years, three counties, Jiangying, Wujiang and Kunshan in the area, were as more as 6 times. Expanded lands are almost rice fields in which average soil productivity is as higher as 7.2t/ha. Rice productivity losses are as higher as 24,000t/ha and 72,000t/ha per year during 1984 - 1992 and 1992 - 2001 respectively. The project achievements can be used as sciences and technology supports when they do similar investigation, research works and make decisions by government and local people.

应用三种卫星遥感资料监测苏州、无锡和常州地区三个时段内城镇用地扩展的面积、分布、速度及其趋势；利用土壤普查资料，用新建的土壤生产力模型评价各类土壤的生产力；把城镇用地扩展图与土壤生产力分布图进行叠加分析，较精确地定量评估和预测城镇用地扩展对粮食生产的影响，为国家和地方政府制订二十一世纪粮食安全供给政策提供科学的依据。