重度干旱条件下典型岩溶区植被恢复过程中植物水分利用来源和效率研究  

Plant Water Use Sources and Efficiency During Vegetation Restoration in Typical Karst Area Under Severe Drought Conditions

作　　者：陈燕 杨慧[1,3,4] 宁静[1,5] 朱德根 吴夏 黄芬 马洋[1] 陈伟 Mitja Prelovšek[7] Nataša Ravbar CHEN Yan;YANG Hui;NING Jing;ZHU Degen;WU Xia;HUANG Fen;MA Yang;CHEN Wei;Mitja PRELOVŠEK;Nataša RAVBAR(Karst Dynamics Laboratory,MNR and Guangxi/Institute of Karst Geology,CAGS,Guilin 541004,P.R.China;Institute of Geological Survey,China University of Geosciences(Wuhan),Wuhan 430074,P.R.China;International Research Centre on Karst under the Auspices of UNESCO/National Center for International Research on Karst Dynamic System and Global Change,Guilin 541004,P.R.China;Pingguo Guangxi,Karst Ecosystem,National Observation and Research Station,Pingguo 531406,P.R.China;School of Water Resources and Environment,China University of Geosciences(Beijing),Beijing 100083,P.R.China;School of Environmental Studies,China University of Geosciences(Wuhan),Wuhan 430074,P.R.China;Research Centre of the Slovenian Academy of Sciences and Art,Karst Research Institute,Titov trg 2,6230 Postojna,Slovenia)

机构地区：[1]中国地质科学院岩溶地质研究所/自然资源部广西岩溶动力学重点实验室,广西桂林541004 [2]中国地质大学(武汉)地质调查研究院,湖北武汉430074 [3]联合国教科文组织国际岩溶研究中心/岩溶动力系统与全球变化国际联合研究中心,广西桂林541004 [4]广西平果喀斯特生态系统国家野外科学观测研究站,广西平果531406 [5]中国地质大学(北京)水资源与环境学院,北京100083 [6]中国地质大学(武汉)环境学院,湖北武汉430074 [7]斯洛文尼亚科学与艺术院研究中心喀斯特研究所,波斯托尼亚SI-6230

出　　处：《生态环境学报》2024年第10期1534-1543,共10页Ecology and Environmental Sciences

基　　金：国家重点研发计划项目(2021YFE0107100);广西重点研发计划项目(桂科AB22035004)。

摘　　要：水分条件是限制西南岩溶地区植物恢复的重要生态因子。目前缺少季节性干旱过程中岩溶区植被恢复过程中主要植被群落水分利用特征差异的系统分析,限制了对岩溶区季节性干旱过程中植物的抗旱机制的理解。为了揭示重度干旱条件下典型岩溶区植被恢复过程中植物水分利用来源和效率,在桂林毛村岩溶生态试验场农田、草地、灌丛和林地等不同植被恢复过程中采集了主要的优势物种附近的0-100 cm深度土壤样品和8种植物茎杆、叶片样品,测定土壤水、植物茎秆水中氢氧同位素与植物叶片的碳同位素,利用贝叶斯同位素混合(MixSIAR)模型确定不同植被恢复阶段主要植物群落水分来源比例,分析水分利用来源和水分利用效率的差异。结果表明,1)重度干旱条件下,研究区除岩溶区灌丛阶段主要利用土壤水外,其他各植被恢复阶段的优势植物均主要利用地下河水。岩溶区农田、草丛、乔木和非岩溶区乔木林的优势物种对地下河水的利用率分别为61.7%±5.3%、70.0%±9.0%、61.5%±10.6%、57.9%±4.8%。而且除岩溶区灌丛阶段优势植物利用0-10 cm深度的土壤水的比例最大外,其他各植被恢复阶段和非岩溶区乔木林的优势植物利用60-100 cm深度的土壤水的比例最大,这与长期干旱表层土壤含水率较低有关。2)除灌丛阶段外,研究区岩溶区各植被恢复阶段优势植物水分利用效率均高于非岩溶区,其中,草丛阶段优势植物的水分利用效率最高,为56.5μmol·mol^(-1)。研究结果有助于理解重度干旱气候下岩溶区生态恢复过程中植物对环境变化的水文调控提供科学数据,为脆弱生态环境保护提供科技支撑。In the karst regions of Southwest China,moisture serves as a pivotal ecological factor that constrains vegetation rehabilitation.On the other hand,water utilization represents a fundamental eco-hydrological process that mirrors the response of vegetation to environmental alterations.Currently,there is a lack of systematic analysis of the differences in water utilization characteristics among major vegetation communities during vegetation recovery processes in karst areas under seasonal drought conditions,which hinders the understanding of plant drought resistance mechanisms in karst regions during seasonal drought processes.To elucidate the sources and efficiency of plant water utilization during vegetation recovery processes in typical karst regions under severe drought conditions,soil samples were collected at depths of 0-100 cm near the dominant species in different vegetation recovery stages,including farmland,grassland,shrubland,and forest,at the Maocun Karst Ecological Experimental Site in Guilin.Stem,leaf,and soil water samples were collected,and the hydrogen and oxygen isotopes in soil,water,plant stem water,and carbon isotopes in plant leaves were determined.The Bayesian isotope mixing model(MixSIAR)was used to determine the proportion of different water sources for major plant communities in different vegetation recovery stages,and to analyze differences in water source utilization and efficiency.The results indicated that under severe drought conditions:1)apart from the shrubland,dominant plants in other vegetation recovery stages mainly utilized underground river water,with utilization rates of underground river water by dominant species in farmland,grassland,woodland,and non-karst woodland being 61.7%±5.3%,70.0%±9.0%,61.5%±10.6%,and 57.9%±4.8%,respectively.Furthermore,except for the shrubland stage,where the proportion of dominant plants utilizing soil water at depths of 0-10 cm was the highest,in other vegetation recovery stages and in non-karst woodlands,the proportion of dominant plants utiliz

关 键 词：重度干旱 岩溶 稳定同位素 植物水分来源和效率 MixSIAR模型 

分 类 号：S157[农业科学—土壤学] X173[农业科学—农业基础科学]