Spatial characteristics of cultivated land quality accounting for ecological environmental condition: A case study in hilly area of northern Hubei province, China

Abstract

Scientific evaluation of cultivated land quality is the premise for ensuring food security and improving land quality. In this research, new evaluation method was developed referring to the Soil Quality Index method, using Xiangzhou District, Hubei province, China, as the studying area. Five first-level indicators including physical and chemical properties, nutrient condition, management condition, health condition and ecological environmental condition of cultivated land were selected for construction of the index system. 28 second-level indicators including topographic position, organic matter, active potassium, effective phosphorus, effective sulfur, effective boron, cadmium concentration, soil runoff nitrogen, soil runoff phosphorus, etc., were selected. Interpolation methods were compared between Inverse Distance Weighted (IDW) method, Spline method and Ordinary Kriging (OK) method at different evaluation scales to reduce the effect of modifiable areal unit problem (MAUP). The IDW method at the small scale was finally performed in the evaluation process. The results showed that the average cultivated land quality index was 6.09 in Xiangzhou District. The main limiting factors of cultivated land quality included soil bulk density, organic matter, effective phosphorus, pH, effective boron, effective sulfur, soil runoff nitrogen and phosphorus. Therefore, land quality improving suggestions were put forward by adopting ecological agricultural engineering and applying suitable organic fertilizer.