白云岩坡地土壤流失空间分布特征及关键影响因子  

Spatial variations and the key driving factors of soil losses on dolomite slopes

作　　者：蒙清梅 付智勇[2,3] 邓羽松 陈洪松[2,3] MENG Qingmei;FU Zhiyong;DENG Yusong;CHEN Hongsong(College of Forestry,Guangxi University,Nanning 530004,China;Key Laboratory of Agro-ecological Processes in Subtropical Region,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha 410125,China;Guangxi Key laboratory of Karst Ecological Processes and Services,Huanjiang Observation and Research Station of Karst Ecosystem,Chinese Academy of Sciences,Huanjiang 547100,Guangxi,China)

机构地区：[1]广西大学林学院,南宁530004 [2]中国科学院亚热带农业生态研究所亚热带农业生态过程重点实验室,长沙410125 [3]中国科学院环江喀斯特生态系统观测研究站,广西环江547100

出　　处：《应用生态学报》2023年第2期377-386,共10页Chinese Journal of Applied Ecology

基　　金：广西自然科学基金项目(2020GXNSFAA297242);国家自然科学基金项目(42077077,U21A20189,41671287)资助。

摘　　要：本研究选择典型白云岩坡地,在上、中、下坡各设置3个土壤流失监测微区(投影长2 m、宽1.2 m),连续观测2个水文年(2020—2021年),分析土壤流失量的动态变化及其关键影响因子。结果表明:白云岩坡地不同坡位的土壤流失量依次为下坡半淋溶土(386 g·m^(-2)·a^(-1))>中坡始成土(77 g·m^(-2)·a^(-1))>上坡新成土(48 g·m^(-2)·a^(-1))。沿坡向下,土壤流失量与土壤表层含水量、降雨量的正相关关系逐渐增加,而与最大30 min雨强的正相关性逐渐降低;影响上、中、下坡土壤流失的气象因子分别为最大30 min雨强、降雨量、平均雨强和表层土壤含水量。上坡土壤侵蚀过程主要由雨滴击溅及超渗产流驱动,而下坡主要由蓄满产流驱动。土壤剖面细土体积占比是控制白云岩坡地土壤流失的关键因子,其解释率达到93.7%。下坡是白云岩坡地土壤流失的关键部位,石漠化治理应基于不同坡位的侵蚀发生机理,因地制宜布设防控措施。We selected a typical dolomite slope and set up three micro-plots(projection length was 2 m,width was 1.2 m)on the upper,middle,and lower slopes to analyze the variations of soil losses and the key influencing factors during two hydrological years(2020-2021).The results showed that soil losses at different slope positions on dolomite slopes followed an order of semi-alfisol in lower slopes(386 g·m^(-2)·a^(-1))>inceptisol in middle slopes(77 g·m^(-2)·a^(-1))>entisol in upper slopes(48 g·m^(-2)·a^(-1)).Downward along the slope,the positive correlation gradually increased between soil losses and surface soil water content,as well as rainfall,while it gradually decreased with the maximum 30 min rainfall intensity.The meteorological factors affecting soil erosion on the upper,middle and lower slopes were the maximum 30 min rainfall intensity,precipitation,average rainfall intensity and surface soil water content,respectively.Soil erosion processes on upper slopes were mainly driven by raindrop splash erosion and infiltration-excess runoff,while that on lower slopes were mainly driven by saturation-excess runoff.The volume ratio of fine soil in the soil profile was the key factor of soil losses on dolomite slopes,with an explanation rate of 93.7%.The lower slope was the key site of soil erosion in the dolomite slopes.Subsequent rock desertification management should be based on the erosion mechanism of different slope positions,while control measures should be arranged according to local conditions.

关 键 词：地形序列 土链 石灰土 白云岩 土壤剖面 产流机制 水蚀过程 

分 类 号：S157.1[农业科学—土壤学]