高原湖泊周边浅层地下水:溶解性碳时空分布及驱动因素  

Shallow Groundwater Around Plateau Lakes:Spatiotemporal Distributions of Dissolved Carbon and Its Driving Factors

作　　者：崔荣阳 陈安强[1] 刘刚才[2] 陈清飞 叶远行 王炽[1] 张丹[3] CUI Rong-yang;CHEN An-qiang*;LIU Gang-cai;CHEN Qing-fei;YE Yuan-hang;WANG Chi;ZHANG Dan(Agricultural Environment Resources Institute,Yunnan Academy of Agricultural Sciences,Kunming 650201,China;Key Laboratory of Mountain Surface Processes and Ecological Regulation,Chinese Academy of Sciences,Institute of Mountain Hazards and Environment,Chinese Academy of Sciences,Chengdu 610299,China;College of Resources and Environment,Yunnan Agricultural University,Kunming 650201,China)

机构地区：[1]云南省农业科学院农业环境资源研究所,昆明650201 [2]中国科学院、水利部成都山地灾害与环境研究所,中国科学院山地表生过程与生态调控重点实验室,成都610299 [3]云南农业大学资源与环境学院,昆明650201

出　　处：《环境科学》2024年第8期4589-4599,共11页Environmental Science

基　　金：云南省兴滇英才项目(202305AS350013);国家自然科学基金项目(42067052)。

摘　　要：地下水中溶解性碳在碳循环和生态功能维持中发挥着重要作用,其浓度水平影响着地下水中污染物的迁移转化.为了解高原湖泊周边浅层地下水中溶解性碳的时空变化特征,分析了云南8个高原湖泊周边浅层地下水(n=404)中溶解性有机碳(DOC)、溶解性无机碳(DIC)和溶解性总碳(DTC)浓度的时空分布及驱动因素.结果表明,高原湖泊周边浅层地下水中ρ(DOC)、ρ(DIC)和ρ(DTC)的均值分别为8.23、49.01和57.84 mg·L^(-1),近79.0%的浅层地下水中ρ(DOC)超过5 mg·L^(-1).季节变化对DOC、DIC和DTC浓度无显著影响,而农业集约化强度和地下水位深度显著影响浅层地下水中溶解性碳浓度变化,表现为设施农业区(SFAR)、农田休耕区(CFAR)和较深地下水位集约化农业区(DIAR)的地下水中DOC、DIC和DTC浓度相比于较浅地下水位集约化农业区(SIAR)分别显著降低了25.8%~56.6%、14.0%~32.9%、16.6%~36.7%,且DIAR地下水中溶解性碳浓度均显著低于SFAR和CFAR.冗余分析(RDA)表明水和土壤中理化因子显著解释了溶解性碳的变化.此外,异龙湖周边浅层地下水中溶解性碳浓度显著高于其它湖泊,程海却显著低于其它湖泊.可见,农业集约化强度和地下水位共同驱动了高原湖泊周边浅层地下水中溶解性碳浓度变化.研究结果以期为了解高原湖区碳随地下径流入湖等区域碳循环及评估浅层地下水中溶解性碳对污染物的衰减提供科学依据.Dissolved carbon in groundwater plays an important role in carbon cycling and ecological function maintenance,and its concentration level affects the migration and transformation of pollutants in groundwater.To understand the spatiotemporal variation characteristics of dissolved carbon and its driving factors in shallow groundwater around plateau lakes,variations in the concentrations of dissolved organic carbon(DOC),inorganic carbon(DIC),and total carbon(DTC)and their driving factors in shallow groundwater(n=404)around eight plateau lakes were analyzed.The results indicated that the average values ofρ(DOC),ρ(DIC),andρ(DTC)in shallow groundwater around plateau lakes were 8.23,49.01,and 57.84 mg·L^(-1),respectively,with theρ(DOC)in 79.0%of shallow groundwater samples exceeding 5 mg·L^(-1).There were no significant differences in the DOC,DIC,and DTC concentrations between rainy and dry seasons,whereas the change in dissolved carbon concentrations in shallow groundwater were strongly affected by the intensity of agricultural intensification and the depth of groundwater table;the DOC,DIC,and DTC concentrations in shallow groundwater from facility agricultural regions(SFAR),cropland fallow agricultural regions(CFAR),and intensive agricultural regions with deeper groundwater tables(DIAR)were significantly reduced by 25.8%-56.6%,14.0%-32.9%,and 16.6%-36.7%,respectively,compared with those in intensive agricultural regions with shallower groundwater tables(SIAR).Additionally,the dissolved carbon concentrations in shallow groundwater from DIAR were significantly lower than those of SFAR and CFAR.RDA revealed that physicochemical factors in water and soil significantly explained the changes in the dissolved carbon concentrations.Moreover,the dissolved carbon concentrations in shallow groundwater around Yilong Lake were significantly higher than those of other lakes,whereas that of Chenghai Lake was significantly lower than that of other lakes.Our study highlights that agricultural intensification intensity and ground

关 键 词：溶解性有机碳(DOC) 溶解性无机碳(DIC) 浅层地下水 高原湖泊 农业集约化强度 

分 类 号：X523[环境科学与工程—环境工程]