Abstract:

In order to provide basis for reasonable utilization of cultivated land and scientific fertilization, it is necessary to evaluate and classify fertility of cultivated land and make feasible suggestions for management. The studied area in this paper was Liyang City, Jiangsu Province, China, 12 factors such as soil parent material, texture, slope, aspect, type of barrier layer, insurance probability of irrigation water, modulus of surface drainage, PH, organic matter, available phosphorous, available potassium, water-soluble boron are selected as the evaluation factors. With the BFIS, a method in both quantitative and qualitative natures was developed to grade the farmland productive capacity, through correlation analysis, factor analysis, fuzzy evaluation, and hierarchic analysis respectively. With the support of software technology, the Cultivated Land Resource Management Information System (CLRMIS) and Geographic Information System (GIS) are used for dealing and combining all kinds of data on properties and spaces. The results showed that, the total area of cultivated land in Liyang City was 58611.1 hm2, which was divided into five levels, i.e., the 1st level with 9905.3 hm2 accounting for 16.9% of the total cultivated land area, the 2nd with 17759.1 hm2 for 30.3%, the 3rd with 22272.2 hm2 for38%, the 4th with 8557.2 hm2 for 14.60%, and the 5th with 117.3 hm2 for 0.2%. In sum, we can base on natural agents of cultivated land to evaluate its fertility with computer technology. The evaluation results can accurately reflect classification of land fertility, and overcome disadvantages of subjective method of classification by experience and avoid blindness of pure mathematical method. Besides, the evaluation results showed that the classification of fertility of cultivated land conforms to the reality of Liyang City, of which the land fertility was comparatively high. Suggestions based on management at different levels are considered to have pertinence and operability, and can be used in production application.