典型喀斯特水库水化学特征及水体营养状态影响因素研究  

Study of hydro-chemical characteristics and influencing factors of the tropic status in typical karst reservoirs

作　　者：付陈乐 康满春 孟江槐 刘佳[1,2] 刘流[3] 龙良红 肖尚斌[1,2] FU Chen-le;KANG Man-chun;MENG Jiang-huai;LIU Jia;LIU liu;LONG Liang-hong;XIAO Shang-bin(Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir,China Three Gorges University,Yichang 443002,China;Engineering Research Center of Ecology and Environment,Ministry of Education,Three Gorges Reservoir Area,Yichang 443002,China;Provincial Key Laboratory of Plateau Geographical Processes and Environmental Change,Faculty of Geography,Yunnan Normal University,Kunming 650500,China)

机构地区：[1]三峡大学,三峡水库生态系统湖北省野外科学观测研究站,湖北宜昌443002 [2]三峡库区生态环境教育部工程研究中心,湖北宜昌443002 [3]云南师范大学地理学部,云南省高原地理过程与环境变化重点实验室,云南昆明650500

出　　处：《中国环境科学》2025年第3期1483-1495,共13页China Environmental Science

基　　金：三峡水库生态系统湖北省野外科学观测研究站(三峡大学)开放基金(2024YWZ05);国家自然科学基金资助项目(51979148,51809149);湖北省自然科学基金创新发展联合基金(2022CFD032)。

摘　　要：水库的水化学特征及营养状态是流域自然条件和人为作用的综合体现,本研究以小湾水库(XW)及丹江口水库(DJK)为研究对象,分析了喀斯特水库水体主要离子变化特征以及氮(N)、磷(P)营养盐的空间变化,解析了水体主要离子来源并分析了水库水体营养状态及其影响因素.结果表明:两水库水化学类型分别为HCO_(3)·SO_(4)-Ca型及HCO_(3)-Ca型,均受岩石风化作用控制,且均具有较高水平的人为输入SO_(4)^(2-)、NO_(3)^(-);水库水体氮、磷主要以溶解态为主,水体无碳限制,但XW受氮限制,DJK受磷限制,水体营养状态均呈中营养水平;受喀斯特地区水化学背景及高风化速率的影响,C、N、P化学计量比为水体综合营养状态指数(TLI)的主要影响因素;水体在不同N、P限制条件下其营养状态的影响因子有所不同,而易受岩石风化、气候变化、人为输入等影响的C:P的值是控制水库水质的关键因素;基于水体氮、磷营养限制条件分析水化学特征、生源要素化学计量比等的影响,优化水体营养状态评价指标,为不同水文条件及功能作用下的喀斯特水库水体营养状态评价、水质管理提供依据.The hydro-chemical characteristics and trophic status of reservoirs are shaped by a combination of natural conditions and anthropogenic effects within the watershed.This study focuses on Xiaowan Reservoir(XW)and Danjiangkou Reservoir(DJK)to analyzes the main ions characteristics and spatial variations of nitrogen(N)and phosphorus(P)nutrients in their water bodies,we identify the primary sources of these ions and interprets the nutrient status of these karst reservoirs,along with the influencing factors.The results show that:The water chemistry of the karst reservoirs is governed by rock weathering,resulting in HCO_(3)·SO_(4)-Ca and HCO_(3)-Ca types for XW and DJK respectively;Both reservoirs exhibit high anthropogenic inputs of SO_(4)^(2-)and NO_(3)^(-);In both reservoirs,nitrogen(N)and phosphorus(P)predominant exist in dissolved forms.While no carbon-limitation was observed,N-limitation is evident in XW and P-limitation in DJK,leading to a mesotrophic status in both reservoirs;The stoichiometric ratio of carbon(C),nitrogen(N),and phosphorus(P)are the primary factors influencing the comprehensive trophic level index(TLI)of the reservoirs.This is attributed to the karst hydrochemical background and high weathering rates;Under different N and P limiting conditions,the trophic status is affected by various factors,with the C to P ratio-sensitive to rock weathering,climate change,and anthropogenic inputs-emerging as a key determinant of water quality;To optimize the evaluation indices for assessing the trophic state and managing water quality in karst reservoirs under diverse hydrological conditions and functional roles,it is essential to analyze the effects of water chemical characteristics and stoichiometric ratios of biogenic elements on trophic status based on the analysis of nutrient limitations in water bodies.

关 键 词：喀斯特水库 水化学特征 离子来源 营养状态 

分 类 号：X142[环境科学与工程—环境科学]