白云岩坡地土壤与表层岩溶带强风化层耦合结构特征  

Spatial Coupling Pattern of Soil Layer and Upper Epikarst Zone on a Dolomite Hillslope

作　　者：唐旭芳 付智勇[2,3] 黄钰涵 王升[2,3,4] 赵杰 陈洪松 TANG Xufang;FU Zhiyong;HUANG Yuhan;WANG Sheng;ZHAO Jie;CHEN Hongsong(Guangxi Key Laboratory of Forest Ecology and Conservation,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;Huanjiang Observation and Research Station of Karst Ecosystem,Chinese Academy of Sciences,Huanjiang,Guangxi 547100,China;Key Laboratory of Environment Change and Resources Use in Beibu Gulf of Ministry of Education,College of Geography and Oceanography,Nanning Normal University,Nanning 530001,China)

机构地区：[1]广西大学林学院广西森林生态与保育重点实验室,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 [4]南宁师范大学地理与海洋研究院北部湾环境演变与资源利用教育部重点实验室,南宁530001

出　　处：《水土保持学报》2025年第1期56-65,共10页Journal of Soil and Water Conservation

基　　金：国家自然科学基金联合基金项目(U21A20189);国家自然科学基金面上项目(42077077);广西重点研发项目(桂科AB22035058);广西科技基地和人才专项青年创新人才科研专项(桂科AD22035032)。

摘　　要：[目的]喀斯特区白云岩坡地植被恢复困难,石漠化治理难度大,其浅薄土层下伏的表层岩溶带深度参与生态系统过程,然而土壤与表层岩溶带二者的耦合发育关系尚不明确。[方法]选择典型白云岩山坡,在全坡面尺度上开展深入表层岩溶带强风化层底部的岩土探槽开挖试验,结合Kriging插值、地理加权回归分析等方法对土壤和表层岩溶带强风化层空间特征进行分析,初步探明白云岩坡地土壤与表层岩溶带强风化层间的空间耦合发育特征。[结果]1)白云岩坡地土壤和表层岩溶带强风化层厚度沿坡向下逐渐增加,坡地尺度上表层岩溶带强风化层平均厚度为50 cm,平均体积为0.47 m^(3)/m^(2),占土壤全剖面总体积的43.9%,说明喀斯特区表层岩溶带的生态功能极其重要;2)白云岩坡地岩土结构呈极强的空间异质性,下伏表层岩溶带强风化层空间异质性(C+C_(0)=18.88)显著高于上覆土壤层(C+C_(0)=15.84);3)土壤总厚度,尤其是土壤B层厚度,与表层岩溶带风化程度呈显著正相关,说明土壤厚度的增加促进下伏表层岩溶带的风化,土壤和表层岩溶带强风化层间呈明显的耦合协同发育关系。[结论]喀斯特地区土壤和表层岩溶带强风化层协同演化,土壤层下伏的表层岩溶带可能是支撑喀斯特生态系统的重要介质,喀斯特水土资源的评估需要考虑除土壤以外的基岩风化层。土壤厚度及土壤发生层B层厚度可能成为预测喀斯特坡地表层岩溶带厚度的关键参数。[Objective]Restoring vegetation and combating rocky desertification on dolomite slopes in karst regions face significant challenges.The upper epikarst zone,which underlies the shallow soil layer,plays a crucial role in ecosystem processes.Nevertheless,the coupling relationships between the soil and the upper epikarst zone remain poorly understood.[Methods]A representative dolomite hillslope was chosen for detailed soil-epikarst system structure investigation through trench excavation method.By integrating Kriging interpolation with geographically weighted regression analysis,the spatial distribution characteristics of different medium layers in the soil-epikarst system were analyzed.The study preliminarily proved the co-evolving feature of the soil and the underlying upper epikarst zone on dolomite hillslopes.[Results]1)The thickness of soil and upper epikarst zone on the dolomite hillslope gradually increased down the slope.The average thickness of the upper epikarst zone on a hillslope scale was 50 cm,with an average volume of 0.47 m^(3)/m^(2),accounting for 43.9%of the total volume of the soil profile,indicating that the ecological function of epikarst in karst regions is extremely important.2)The soil-epikarst system′s structure of the dolomite hillslope exhibited strong spatial heterogeneity.The spatial heterogeneity of the underlying upper epikarst zone(C+C_(0)=18.88)was significantly higher than that of the overlying soil layer(C+C_(0)=15.84);3)The overall soil thickness,especially the B horizon′s thickness,was significantly positively correlated with the upper epikarst zone′s weathering degree,indicating that the increase of soil thickness promoted the weathering of the underlying upper epikarst zone,and there was a clear coupling and collaborative development relationship between soil and upper epikarst zone.[Conclusion]The soil and upper epikarst zone in karst regions have evolved in a mutually reinforcing manner.The upper epikarst zone acts as an essential substrate for supporting the karst ecosy

关 键 词：喀斯特关键带 土壤-表层岩溶带系统 喀斯特生态系统 岩溶过程 土壤发育 

分 类 号：S152[农业科学—土壤学]