Effects of Soil Erosion Intensity on Aggregate Size Distribution and Nutrient Content in Red Soil Region
[Objective] The objective of the paper is to study the variation of soil aggregate distribution,nutrient content and their correlation under different soil erosion intensities in red soil region,and provide the theoretical basis for improving the soil fertility and reasonable development and utilization of red soil.[Methods] The tested soil was sampled from different layers below the surface to simulate the natural soil erosion of different intensities,and soil aggregate distribution,nutrient content and their correlation was investigated.[Results] The aggregate size showed similar pattern in red soil with different erosion intensities,and was dominated by the aggregate size ≥2 mm.Compared to CK,≥2 mm water stable aggregate content decreased by 1/3.With the increase of erosion intensity,the contents of nutrients,including organic matter (OM),total nitrogen (TN),total phosphorus (TP),anailable nitrogen (AN),and available phosphorus (AP),aggregate mechanical stability and water stability decreased.The content of OM,TN and TP in severely eroded soil decreased by 30％,AP by 50％ and AN by 80％,respectively.Correlation analysis showed that the content of soil organic matter,TN,TP and AN significantly and positively correlated with ≥2 mm aggregate,＞0.25 mm aggregate(WSA),the mean weight diameter(MWD) and geometric mean diameter(GMD) (p＜0.05),whereas correlated negatively with aggregate fractal dimension(D) and percentage of aggregate disruption(PAD).[Conclusion] The soil erosion intensity affects soil aggregate distribution and nutrient content,and the application of organic fertilizer in red soil plays an important role in improving soil structure and fertility.
red soilerosion intensitysoil aggregateorganic matternitrogenphosphorus
国家科技期刊平台
NSTL
万方数据
维普
