向家坝工程扰动区不同生态修复模式边坡土壤颗粒分形特征

[目的]研究不同生态修复后边坡土壤颗粒分形特征，为分形维数作为评价修复后向家坝工程扰动区边坡土壤质量的综合指标提供科学依据。[方法]以向家坝工程扰动区6种不同生态修复模式下的0—10 cm边坡土壤为研究对象，通过野外采样和室内试验，采用单重和多重分形理论相结合的方法，研究自然演替与人工修复模式下土壤粒径分布(PSD)和分形特征及土壤养分特征并分析了其相关关系。[结果]不同生态修复模式下土壤颗粒组成以粉粒和砂粒为主，黏粒含量较少，粒径分布不均匀。天然林地土壤养分含量相对较高且土壤颗粒较细。黏粒与D_v呈极显著正相关(p<0.01),与土壤有机碳和速效氮呈显著正相关(p<0.05),粉粒含量与D₁,D₂呈极显著负相关(p<0.01),砂粒与D₁,D₂呈极显著正相关(p<0.01)。土壤养分与黏粒、粉粒含量呈不显著正相关，与砂粒含量，D₁,D₂呈不显著负相关。[结论]向家坝工程扰动区土壤颗粒以粉粒和砂粒为主，土壤质地较...

Fractal Features of Soil Particles Under Different Ecological Remediation Modes of Xiangjiaba Project

[Objective] The fractal characteristics of soil particles in slope after different ecological restoration was studied to provide a scientific basis for the fractal dimension as a comprehensive index to evaluate the soil quality of slope in the disturbed area of XiangJiaba Project after restoration. [Methods] Soils in the depths of 0 to 10 cm in six different ecological remediation modes of the Xiangjiaba Project were used in this study. Monofractal and multifractal theory was used to measure and analyze soil particle size distribution(PSD), soil fractal features, soil nutrient contents and their correlations from natural succession and artificial restoration. [Results] Soil particle composition under different ecological remediation modes is dominated by silt and sand particles, with less clay particles and uneven particle size distribution. Clay content was highly significantly positively correlated with D_V(p<0.01), significantly positively correlated with soil organic carbon and rapidy available nitrogen(p<0.05), silt content was highly significantly negatively correlated with D₁ and D₂(p< 0.01), and sand content was highly significantly positively correlatedn with D₁ and D₂(p<0.01). Soil nutrients were positively and insignificantly correlated with contents of clay and silt and negatively insignificantly correlated with content of sand, D₁ and D₂. [Conclusion] The soil particles in the disturbed area of Xiangjiaba Project are mainly silt and sand, and the soil texture is coarse. The vegetation concrete restoration technology is conducive to the accumulation of fine particles, so as to improve the soil uniformity, which can be used as a reference for ecological restoration. Silt and sand not only dominate the multifractal parameters, but also promote the nutrient, which can be used as the scale of ecological restoration effect in the study area.