土壤理化性质与土壤溅蚀速率的相关性研究

土壤溅蚀是土壤侵蚀的初始阶段,是降雨雨滴直接打击土壤表层引起的土壤颗粒分散和位移发生的过程。为研究土壤理化性质与土壤溅蚀速率的相关性,研究通过人工模拟降雨溅蚀试验测定土壤溅蚀速率,运用SPSS 20.0软件,对土壤理化性质与土壤溅蚀速率进行了Pearson相关系数分析。结果表明:土壤渗透性、分散率、团聚度和土壤粒级与土壤溅蚀速率相关性最大。土壤的渗透系数在整个降雨历时阶段对土壤的溅蚀速率一直呈现负影响。分散率在降雨历时为15min时对土壤溅蚀速率呈显著负影响。团聚度对土壤溅蚀速率的影响由T=15min时的显著正相关变成T=20min时的极显著正相关。土壤粒级和土壤溅蚀速率相关性很大,且关系较为复杂。相较于其他4种粒级中,粒级范围在D0.002mm的土壤颗粒对土壤溅蚀速率影响最大,且在降雨历时为15~20min时,对土壤溅蚀速率皆有显著正相关性。另外,粒级范围在0.2≤D2mm和0.02≤D0.2mm的土壤颗粒分别在T=15min和T=20min时对土壤溅蚀速率有显著负相关性。土壤粒级对土壤溅蚀速率的相关性随降雨历时的变化可能与土壤结皮有关。

Correlations Between Soil Physical-Chemical Proprieties and Soil Splash Erosion Rate

Soil splash erosion is the beginning of soil erosion process,and results in soil particle dispersion and migration when the raindrop directly blows topsoil.To study the correlations between soil physical-chemical proprieties and soil splash erosion rate,we measured soil splash erosion rate based on artificial simulated rainfall splash erosion experiment,and used SPSS 20.0 software to analyze the Pearson correlation coefficient between the soil physical-chemical properties and soil splash erosion rates.The results show that soil permeability,dispersion rate,aggregation and soil particle have a great influence during the rainfall;soil permeability has negative effects on erosion rate in the whole duration of rainfall;the dispersion rate has a significant negative impact on the soil erosion rate when rainfall duration is 15 minitues;the correlation between aggregation and soil splash erosion rate changes from positive correlation when T=15 min to significantly positive correlation when T=20 min;soil particles are strongly correlated with soil splash erosion rate,and the relationship is more complex.Compared to the other four kinds of grain size,＜0.002 mm soil particle has the greatest impact on soil erosion rate,and has a significant positive effect during the latest two rainfall events.0.2≤D＜2 mm or 0.02≤D＜0.2 mm soil particle has a significant negative correlation on soil erosion rate when T=15 min and T=20 min,respectively.The correlation of soil erosion rate with soil particle sizes may be related to the soil crust.