黔中喀斯特地区不同岩性土壤的抗蚀抗冲性研究

对贵州省中部喀斯特地区4种典型成土母岩(灰质白云岩,石灰岩,长石石英砂岩,白云岩)发育的土壤的抗蚀抗冲性进行研究。结果表明:可将衡量土壤抗蚀性的12个指标压缩为3个最佳指标。抗蚀性指标主成分分析综合指数表明,4种岩性土壤抗蚀性为:灰质白云岩(43.42)>石灰岩(5.49)>白云岩(2.72)>长石石英砂岩(-34.49);15°、20°、30°3个坡度下的抗冲性显著不同,随着坡度的增加,4种岩性土壤抗冲性显著差异也逐渐增加;4种岩性土壤抗冲性变化规律与抗蚀性吻合,土壤抗冲性强弱与抗蚀性强弱趋于一致。土壤的抗蚀性与抗冲性与成土母岩的性质关系密切。

Anti-Erodibility and Anti-Scourability of Different Lithological Soils in Karst Area of Central Guizhou Province

Anti-erodibility and anti-scourability of 4 typical soil-forming rocks(calcific dolomite stone,limestone,feldspathic quartzose gritstone and dolomite stone) in Karst area in central Guizhou were studied.Principal component analysis(PCA) was used in the soil anti-erodibility indexes.Experiments of soil scourability were conducted with different gradients under water dipping and scouring.The result showed that the 12 anti-erodibility indexes could be scaled down to the 3 optimal indexes.PCA comprehensive exponent of anti-erodibility indexes showed the order of anti-erodibility,which were calcific dolomite stone(43.42) > limestone(5.49) > dolomite stone(2.72) > feldspathic quartzose gritstone(-34.49).Soil anti-scourability was distinct in each gradient between 15°,20°and 30°.The distinctness increased by the augment of gradient.Change of soi1 anti-scourability was in agreement with soil anti-erodibility.There was close relationship between the characters of soil-forming rocks and the soil anti-erodibility and anti-scourability.