Study on Synthetic Evaluation Index Systems of Soil Quality in Coastal Reclamation Region
海涂围垦区土壤质量综合评价的指标体系研究

Some soil physico-chemical properties relevant with crop growth were selected as the evaluation indices and then soil quality in typical coastal reclamation region in north Jiangsu Province was quantitatively assessed by using fuzzy mathematics. Synthetic evaluation maps of soil quality status were generated and the results of different evaluation index systems were further compared. Results indicated that soil quality across the study area was generally poor. Soil organic matter (SOM) was the most important evaluation factor of soil quality, while soil salinity and groundwater mineralization were the limiting factors of soil quality. Classification maps of soil quality evaluated by different schemes were quite similar in spatial patterns, and soil quality in cotton-growing field was superior to that in rice-growing field generally. Bulk density had an insignificant influence on evaluation results, which was contrary for available nutrients. The evaluation accuracy based on available nutrients was better than that based on total nutrients. Evaluation index systems including SOM, available nutrients and salinity or merely SOM and salinity could be used to evaluation soil quality when evaluation data were limited. The results can serve as a theoretical reference for the establishment of practical evaluation index systems, scientific amelioration and management of moderate-and-low-yield farmlands in coastal reclamation region.