岩溶断陷盆地高原面洼地不同坡位土壤抗蚀性研究

A Study of Soil Anti-erodibility of Different Slope Positions on Plateau Depression in Karst Gabin Basin

为揭示断陷盆地区高原面洼地不同坡位土壤的抗蚀性能,以高原面洼地不同坡位灌草地(上坡、中坡、下坡、坡底)不同土层(0-20 cm、20-40 cm)土壤为研究对象,通过对土壤抗蚀性16个指标的测定与分析,研究了不同坡位对土壤抗蚀性的影响。结果表明:在不同深度土层中,土壤水稳性大团聚体含量都呈现出上坡>下坡>坡底>中坡(P<0.05),且随着土层深度的增加含量减少;各坡位土壤抗蚀性,0-20 cm土层,上坡>下坡>坡底>中坡(P<0.05),20-40 cm土层,下坡>坡底>上坡>中坡(P<0.05),随着土层深度的增加,土壤抗蚀性逐渐降低;粘粒、有机碳、电导、PAD、MWD湿为评价喀斯特断陷盆地坡位土壤抗蚀性的最佳五指标。建议根据各坡位土壤抗蚀性的差异采取不同措施,减小水土漏失同时增强土壤的抗蚀能力,以改善当地生态环境。

In order to reveal the anti-erodibility of soil of different slope positions on Plateau depression in karst gabin basin,the authors took the soil of different soil layers(0-20 cm,20-40 cm)in different slope positions(up slope,middle slope,downhill and slope bottom)in plateau depression area as the research object.Through the determination and analysis of 16 soil anti-erodibility indexes,the influence of different slope positions on soil anti-erodibility was studied.The results are as follows:In different depths of soil layer,the content of soil water stable macro-aggregate is in order of up slope>downhill>slope bottom>middle slope(P<0.05),decreasing with soil depth.The soil anti-erodibility is in order of 0-20 cm soil layer,up slope>downhill>slope bottom>middle slope(P<0.05),0-40 cm soil layer,downhill>slope bottom>upper slope>middle slope(P<0.05).With the increase of soil depth,soil anti-erodibility gradually decreases;clay,organic carbon,electric conductance,PAD and MWDwet are five best indexes for evaluating the soil anti-erodibility of slope position in karst fault basin.It is suggested that different measures should be taken according to the difference of soil anti-erodibility of different slope positions,so as to reduce water and soil leakage,enhance soil anti erosion capability and improve the local ecological environment.