亚热带岩溶森林类型和坡位对碳酸盐岩溶蚀的影响  

Influence of forest types and slope positions on dissolution rates of carbonate rocks in the karst area in subtropical China

作　　者：侯满福[1,2] 刘雨婷 张杰 贺露炎 梁江弈 HOU Manfu;LIU Yuting;ZHANG Jie;HE Luyan;LIANG Jiangyi(College of Environment and Resources,Guangxi Normal University,Guilin,Guangxi 541004,China;Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection,Ministry of Education(Guangxi Normal University),Guiling,Guangxi 541004,China;School of Geography and Resource Science of Neijiang Normal University,Neijiang,Sichuang 641100,China;Key Laboratory of Wetland Ecology and Environment,Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun,Jilin 130102,China)

机构地区：[1]广西师范大学环境与资源学院,广西桂林541004 [2]珍稀濒危动植物生态与环境保护教育部重点实验室(广西师范大学),广西桂林541004 [3]内江师范学院地理与资源科学学院,四川内江641100 [4]中国科学院东北地理与农业生态研究所,湿地生态与环境重点实验室,吉林长春130102

出　　处：《中国岩溶》2023年第4期842-852,共11页Carsologica Sinica

基　　金：国家自然科学基金(31960233);广西师范大学博士启动基金。

摘　　要：文章采用标准溶蚀试片法对比两种亚热带岩溶森林不同坡位的碳酸盐岩溶蚀速率,并分析其与土壤CO_(2)含量(pCO_(2))和土壤含水量的对应关系。结果表明:青冈林的平均溶蚀速率(5.22±0.99 mg·cm^(−2)·a^(−1))显著高于化香树林(3.58±2.59 mg·cm^(−2)·a^(−1));青冈林的土下溶蚀速率在垂直剖面上先增加后递减,峰值位于土下20 cm,而化香树林的随土壤深度增加而增加;青冈林不同坡位的溶蚀速率差异不显著,而化香树林中坡显著高于上坡和下坡;不同森林类型坡位间的溶蚀速率未表现一致规律。森林类型间溶速率差异与土壤含水量有较好的对应而与土壤pCO_(2)相反,森林内坡位间及土壤垂直剖面的溶蚀速率差异与土壤pCO_(2)有更好对应性。亚热带不同岩溶森林类型间溶蚀速率差异显著,可用土壤含水量较好解释;不同坡位间差异没有一致规律,但可用土壤pCO_(2)较好解释。Carbonate rock weathering has great carbon sink potential.Vegetation is an important driven factor of carbonate rock dissolution.However,the relationship between vegetation types and carbonate weathering is still left unknown.In order to reveal the effects of forest types on carbonate rock weathering,the dissolution rates of carbonate rocks at different slope positions in two typical subtropical karst forests were compared in details based on the in-situ dissolution tests of standard rock test pieces,and the corresponding relationship between the rates and soil CO_(2) content(pCO_(2))and soil water content(SWC)were analyzed based on seasonal measured data.The study area is located in the suburb of Guilin,South China,which has a subtropical seasonal climate with an average annual temperature of 20.2℃and an average annual precipitation of 1,996.0 mm.Precipitation is concentrated from April to September,synchronous with the high temperature in summer.The landforms of peak cluster depressions and peak forest plain around the study area are the most typical in the world and were added to the UNESCO's World Heritage List in 2014.Stretching from the foot to the place near the peak of limestone hills,Cycolobalanopses glauca forest and Platycarya strobilacea forest,the representatives of subtropical karst forests,were selected as research objects in the study area.The community dominated by C.glauca is widely distributed in the karst region of N25°-N31°and E105°-E120°,and is the most important climax community in the subtropical karst region of China.P.strobilacea is one of the most common dominant species or constructive species in evergreen and deciduous broad-leaved forests,forming a more widely distributed forest type than C.glauca forest in the subtropical karst area.Standard rock test pieces were respectively placed in the air 100 cm above ground,on the surface of soil,-20 cm,-50 cm,and-70 cm(if possible)in the soil of downhill slope,middle hill slope and uphill slope from 30/11/2014 to 17/12/2017 in each fore

关 键 词：标准溶蚀试片 碳酸盐岩风化 溶蚀速率 森林类型 碳汇 

分 类 号：P642.25[天文地球—工程地质学] X171.1[天文地球—地质矿产勘探]