Evaluation of the Soil Nutrients of Added Cultivated Land Based on Entropy Weight-Fuzzy Comprehensive Method: A Case Study in Chengcheng County, Shaanxi Province

摘要

In this paper, through the sampling analysis, the entropy weight - fuzzy comprehensive evaluation was adopted to distribute the weight of added cultivated land fertility in Taiyuan District of Weibei, and the soil fertility in the region was further evaluated. At the same time, the main limiting factor impacting soil fertility of the added cultivated land was put forward. The results indicate that 1) Indicators of soil fertility weight of newly-increased farmland in Taiyuan District of Weibei region are as follows: organic matter 20.19%, total nitrogen 20.40%, Olsen-P 33.56%, and Olsen-K 25.85%. 2) The soil fertility scores of these farmland in Chengcheng County under the land consolidation project are dispersed with values ranging from 4.80 to 20.96, with the mean of 11.80. 3) Available phosphorus (AP), soil organic matter (SOM) and available potassium (AK) are the major factors behind low soil fertility indexes. The extent of their impact on soil fertility is ranked as follows: AP>AK>SOM. 4) AP and AK are the most important constraints which lead to low soil fertility of new farmland. The most effective way to improve the composite index of soil fertility is that the content of AK, AP and SOM in the soil should be increased successively. And priority should be given to AP and AK. 5) The adoption of a combination of Analytic Hierarchy Process and weight comparison method has yielded good results in evaluating soil fertility, which implies broad prospect of application.