粤北岩溶山地土壤垂直渗漏特征及影响要素分析

Characteristics and Affecting Factors of Soil Vertical Leakage of Karst Mountains in Northern Guangdong

为更准确地研究岩溶山地土壤垂直流失量,选择粤北连县威建水泥厂一座弃置采石场山体6个不同方位剖面,利用电子全站仪和GPS对各剖面的高度、长度、坡度、走向、节理和漏斗、裂隙、孔穴等进行详细测量,并调查坡面植被覆盖度、土层厚度、岩石裸露率等数据。结果表明:岩溶山地表层岩溶带0~15 m深度范围漏斗、裂隙、孔穴发育,密度分别达到0.17个/100 m^2、0.06条/100 m^2和0.03个/100 m^2。漏斗土、裂隙土和孔穴土体积分别占山体总体积的1.87%、0.36%和0.19%,分别占到山体表层土壤总体积的281.08%、53.29%和28.37%,土壤垂直渗漏总量是表层土壤体积的362.74%。岩溶山地土壤垂直流失是地质运动与地表过程长期共同作用的结果,基岩类型、地貌、地形、节理、气候、人类活动是影响岩溶土壤垂直流失的主要因素。现代岩溶环境的特征与岩溶土壤垂直渗漏关系密切。

In order to accurately study the soil vertical loss of Karst mountainous area,it selected six sections in different directions of a discarded quarry of Weijian Cement Plant in Lianxian County of northern Guangdong,it made detailed survey of height,length,slope,direction,joint,funnel,fissure and cavity of each section by using Electronic Total Station and GPS and investigated the data of vegetation coverage,soil thickness and rock exposed rate. The outcomes show that the funnel,fissure and cavity are developed in the 0 ~ 15 m depth range of surface karst and the densities reach to 0.17 / 100 m2,0.06/100 m2 and 0.03 / 100 m2 respectively. The soil volumes of funnel,fissure and cavity make up 1.87%,0.36% and 0.19% of the total mountain volume and 281.08%,53.29% and 28.37% of the total soil volume of mountain surface respectively. The total soil vertical leakage is 362.74% of the total surface soil volume. The soil vertical leakage of Karst mountain is the result of thousands of years of long-term effects of geological movement and surface process. The types of bedrock,landform,topography,joint,climate and human activities are the main factors that affect the karst soil vertical leakage and is also closely related to the characteristics of modern Karst environment.