| The average of cultivated land is limited,and the reserving arable land is shortage in Anhui province. In order to realize population, resources and environment for sustainable development, must to enhance the study in fertility of arable land, and improve the quality of cultivated land. However,the second soil investigation have past more than 20 years,during this period, the cultivated land quality and soil fertility status have changed greatly, So it is necessary to carry on new and overall investigation and evaluation.The study area in this paper is the Mingguang city which is in hill and hillock region of Anhui Jianghuai.On the support of GIS and computer technologies, 12 indicators were chosen to evaluate cultivated land productivity using the Delphi method,and then the weight of each factor was determined by AHP(Analytic Hierarchy Process). The paper set membership functions in terms of their characteristics and different influence on the quality of cultivated land using fuzzy mathematics method. Base on GIS and database sotfware, the cultivated land resource database was constructed. Meanwhile,applying the fuzzy comprehensive evaluation model to get the integrated fertility index of cultivated land,and using cumulative frequency curve method classify the cultivated land, Simultaneously to manufacture the grades map of cultivated land productivity.At the same time, Among the process of studying fertility of cultivated land in Mingguang, this paper studyed the spatial variability of soil nutrients,such as organic matter,total nitrogen,phosphorus and available potassium that impact on crop yeild, and initially evaluated the soil nutrient status.Moreover, There are remarkable differences of soil type,farming management and site conditation in different types of cultivated land area, So we separately constructed indicator systems for the damp-soil plain area,paddy field area and hilly area of mountain, and separately evaluated the productivity of the three areas of cultivated land type. Simultaneously, Comparatively analyzed the results of the whole evaluation and the respective evaluation to study the status of productivity of cultivated land. The main results obtained in this paper are summaried as follows:1.Spatial variability of soil nutrients. Made the spatial distribution map of the main soil nutrients using Geostatistic and GIS, to understand the spatial distribution of each nutrient clearly.The result indicated that the organic matter,total nitrogen,phosphorus and available potassium all presented moderate variability,and the variation coefficients showed in order of P>K>N>OM..The results from the semi-variance structures of Geostatistic indicated that OM, N, K exhibited moderate spatial variability,which were caused by structure and random factors, however, P displayed weak spatial variability,which were mainly caused by the random factors. Moreover, the spatial distribution of soil nutrient content was different from each other, but there was also a certain similarity in some area.Organic matter showed higher content in middle area than in southern area, while the content of southren area is higher than in the nothern area; the spatial distribution of total nitrogen is similar to the organic matter; soil available phosphorus content was generally higher in south-east than the midwest area; soil available potassium content was higher in the midnorth area ,and the content was more and more lower out of the midnorth area.2. Evaluation of soil nutrient status. On the basis of spatial distribution pattern of soil nutrient, the soil nutrient status was primarily evaluated according to the classification criterion of soil nutrient content of Mingguang.The results showed that soil nutrient content in Mingguang was lower in general and there were certain differences among the soil nutrient content of different cultivated land types.3.Evaluation of cultivated land productivity of Mingguang. According to the integrated fertility index of all the evaluate units, cultivated land in Mingguang was classified into five grades using the cumulative frequency curve method. Grading Map of cultivated land productivity and statistic was were carried out using Mapgis6.7.The area and percentage of the first ,second ,third ,fourth ,fifth grade were 13429.76ha, 12.3%, 27732.99ha,25.4%, 38869.86 ha, 35.6%, 38869.86 ha, 18.6%, 8843.99 ha, 8.1%。The area of different grade of cultivated land displayed third>second>fourth>first>fifth.At the same time,we got the status of the geographical distribution and administrative regional distribution of different grade of cultivated land.4.Evaluation of different types of cultivated land area. We separately constructed indicator system for the damp-soil plain area,paddy field area and hilly area of mountain, and separately evaluate the productivity of the three areas of cultivated land type.Classfied four grades in the damp-soil plain region,the area of different grade showed in the order of the second (37.2%)>third(36.3%)>first(21.1%)>fourth(5.3%); and classfied four grades in the paddy field region, the area of different grade showed in the order of the second (60.4%)>third(21.1%)>first(12.5%)>fourth(6.0%); and classfied five grades in the hilly region of mountain, the area of different grade showed in the order of the second (39.9%)>fifth(26.5%)>third (11.9%)>fourth(11.7%)>first(10.0%).5. Comparation of the results in the whole evaluation and the different area evaluation of cultivated land productility . There were remarkable difference between the whole indicator system evaluation result and respective evaluation result in the same area. But there was a certain degree of linear correlation between them. The relevance showed in the order of hilly area of mountain > damp-soil plain region> paddy field area. And the cultivated land productivity generally showed in the order of paddy field area> damp-soil plain area> hilly area of mountain in Mingguang city.Finally,descriptively analyzed the character of different grades of cultivated land. And combined with the actual situation in the study area, the model for utilizing cultivated land and improvement measures were proposed exploratory in the paper.An effective method and technical process in using GIS to develop the evaluation on cultivated land poductivity in hilly area of Jianghuai was put forward in this research. It had positive significance not only on the scientific management and sustainable utilization of farmand in the hilly area of Jianghuai, but also on the being carried projects of Balanced Fertilization on Soil Testing and Evaluation of Cultivated Land Productivity .
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