A quantitative evaluation system of soil productivity for intensive agriculture in China

A system for the quantitative evaluation of soil productivity was developed and deployed in Gaoyou County, China. The study area, comprising 81,600 ha of cultivated land, was divided into 7367 evaluation units, and 19 soil properties were selected as factors for evaluation. Fuzzy analysis and expert score ranking combined with the Delphi method were used to quantify the membership functions of the evaluation factors selected. The weight contributions of individual factors to soil productivity were determined using the Delphi method and an analytic hierarchy process (AHP). A geographic information system (GIS) was used to manipulate the spatial database of the study area. This evaluation system, which differentiates between the concepts of land productivity and soil productivity, has several advantages compared with the China Agriculture Ministry Land Evaluation System (CAMLES), and can deliver detailed soil information to help decision makers and farmers identify the optimal agricultural management practices for achieving higher soil productivity and sustainable soil use. The proposed system has been accepted as the standard method for evaluating soil productivity in China. (C) 2004 Elsevier B.V. All rights reserved.