碳酸盐岩的物性特征对岩溶石漠化成因的影响

Influence of physical characteristics of carbonate rocks on the genesis of karst rocky desertification

以贵州省潜在、轻-中度以及中-强度石漠化地区为研究区域,从宏微观角度分析了碳酸盐岩物理、化学特性对石漠化成因的影响,得出以下结论:碳酸盐岩的CaO和MgO含量、表面粗糙程度、晶粒大小及内部孔隙结构等都与其溶蚀量和风化成土速度密切相关,岩石的抗压强度也与石漠化发育程度成正比。石灰岩易形成差异性溶蚀,发育的孔隙裂隙使得土壤快速流失而易于形成差异性石漠化现象;白云岩溶蚀和成土速度慢于石灰岩,易于发生崩解而形成白云岩碎块最后风化成土,表现为土壤浅薄的潜在石漠化现象。

Taking the potential,light to moderate and medium to severe rocky desertification areas in Guizhou Province as the research area,the influence of physical and chemical characteristics of carbonate rocks on the genesis of rocky desertification is analyzed from the macro and micro perspectives.The following conclusions are drawn:the contents of CaO and MgO,surface roughness,grain size and internal pore structure of carbonate rocks are closely related to the dissolution amount and weathering rate.The compressive strength of rock is also in proportion to the development degree of rocky desertification.Limestone is easy to form differential dissolution,and the developed pore fissures make the soil lose rapidly,which makes it easy to form differential rocky desertification phenomenon;dolomite dissolution and soil formation rate is slower than limestone,and it is easy to disintegrate into fragments and finally become soil by weathering,which shows the potential rocky desertification phenomenon with thin soil layer.