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土壤抗蚀性是评价土壤抵抗侵蚀能力的重要参数之一,植被恢复过程可引起土壤抗蚀性变化。本文通过野外调查与室内分析,运用主成分分析法对不同林龄新银合欢人工林土壤抗蚀性进行综合研究。结果表明:1)随着林龄的增长,新银合欢人工林土壤的通透性和结构稳定性变差,土壤细颗粒含量增加,土壤的养分含量有所降低;2)不同林龄新银合欢人工林土壤抗蚀性综合指数大小表现为:10年生>16年生>27年生,这说明随着林龄的增长,蒋家沟泥石流频发区新银合欢人工林土壤抗蚀性呈下降的趋势;3)表征土壤抗蚀性的13个指标可简化为:土壤密度、最大持水量、>0.25 mm水稳性团聚体含量、黏粒含量、粉粒含量5个指标,以此为自变量,以土壤抗蚀性综合指数为因变量,进行回归分析得出的评价模型为Y=-8.691X1+0.054X2+0.700X3-0.425X4-0.189X5-12.511,线性拟合程度较好。研究结果可为泥石流频发区土壤抗蚀性的后续研究及评价指标体系的构建提供参考。
Soil erosion resistance is one of the most important parameters to evaluate soil resistance to erosion. Vegetation recovery can cause changes in soil erosion resistance. In this paper, through field investigation and laboratory analysis, the principal component analysis method was used to comprehensively study the soil erosion resistance of the new plantation. The results showed as follows: 1) With the increase of forest age, the permeability and structural stability of the soil were deteriorated, the content of soil fine particles increased and the soil nutrient content decreased. 2) The comprehensive index of soil anti-erodibility of Acacia plantation showed as follows: 10-year-old> 16-year-old> 27-year-old, which showed that the soil corrosion resistance of Acacia confusa plantation decreased with age Trend; 3) 13 indicators that characterize soil erosion resistance can be simplified as: soil density, maximum water holding capacity,> 0.25 mm water-stable aggregate content, clay content and grain content as indicators , And the regression model of soil anti-corrosive composite index was taken as the dependent variable. The evaluation model was Y = -8.691X1 + 0.054X2 + 0.700X3-0.425X4-0.189X5-12.511, and the linear fitting degree was better. The results can provide references for the follow-up study of soil erosion resistance and the construction of evaluation index system in debris flow-prone areas.