Abstract:
Objective In order to select suitable evaluation methods for soil quality in typical fluvo-aquic soil region, soil quality under different planting systems was evaluated.
Method The typical fluvo-aquic region of North China was taken as the study area, combined the measured and investigation data, the principal component analysis method was used to select the minimum data. Based on the two scoring methods of linear and nonlinear and three different soil quality index methods of SQIa, SQIw and SQIn, the optimal method was selected to evaluate the soil quality under different planting systems in typical fluvo-aquic area.
Result ① Descriptive statistical analysis showed that the coefficient of variation of soil pH in the fluvo-aquic soil region of central Hebei Province belongs to weak variability, while the other indices belong to moderate variability, and the coefficients of variation of available phosphorus, cation exchange capacity, organic matter and soil available nutrients are relatively large. ② Correlation studies showed that crop yield per unit area was significantly positively correlated with organic matter, total nitrogen and slowly available potassium, and negatively correlated with available potassium, water-soluble boron, pH, available copper, available zinc and available copper. ③ The results showed that the minimum data set of typical fluvo-aquic soil area were organic matter, slowly available potassium, available iron, hydrolytic nitrogen, available zinc, available phosphorus and available sulfur. The correlation between MDS and TDS by different methods is as follows: SQIw-NL > SQIa-NL > SQIw-L > SQIa-L > SQIn-L > SQIn-N. ④ The spatial characteristics showed that the soil quality in the study area was mainly dominated by medium grade II, III and IV. The soil quality index (SQI) decreased from south to north. ⑤ Land use research showed that the order of soil quality of different planting systems was as follows: wheat-corn / bean > peanut > wheat-corn > cotton > corn.
Conclusion The best soil quality evaluation method in the fluvo-aquic soil region of North China is SQIw-NL method, and the minimum data set are organic matter, slowly available potassium, available iron, hydrolytic nitrogen, available zinc, available phosphorus and available sulfur. Different management measures affect the growth and development of crops to a certain extent, and wheat-corn / bean rotation can improve soil quality, and the soil quality of Xianxian County is relatively higher.