Evaluation of farmland productivity on the earth and rockyarea of the South Loess Plateau

On the basis of the field investigation, field sampling and chemical analysis, farmland productivity in Chencang District, Baoji City was evaluated via GIS, Analytical Hierarch Program (AHP) and Fuzzy Mathematical Theory (FMT). The results show that farmland productivity in the study area can be classified into six grades. Grade 1 area accounts for 3.7%, grade 2 for 17.2%, grade 3 for 36.8%, grade 4 for 24.1%, grade 5 for 9.4% and grade 6 for 8.9% of the total area, respectively. The first three grades of farmland are mainly irrigated lands, orchards and vegetable fields, in that order. Grade 4 occurs in every township. Grades 5 and 6 (which are farmlands) mainly occur in the mountain areas with steep slopes, high altitudes and thin layers of soil. Analysis of the characteristics of each grade for every township is beneficial for scientific management of farmlands, sustainable use soils and soil fertilization.