%0 Journal Article %T 三峡大坝上下游水质时空变化特征 %T Spatial-temporal variations of water quality in upstream and downstream of Three Gorges Dam %A 张馨月 %A 马沛明 %A 高千红 %A 严海涛 %A 钱宝 %A ZHANG,Xinyue %A MA,Peiming %A GAO,Qianhong %A YAN,Haitao %A QIAN,Bao %J 湖泊科学 %J Journal of Lake Sciences %@ 1003-5427 %V 31 %N 3 %D 2019 %P 633-645 %K 水质;多元分析;时空变化特征;三峡大坝;上下游 %K Water quality;multivariate analysis;spatio-temporal distribution characteristics;Three Gorges Dam;upstream and downstream %X 为探索三峡大坝上下游(坝上99.9 km、坝下63.0 km、全长162.9 km)水质时空变化特征,运用主成分分析和方差分析对2016年近坝段水质时空变化特征进行了分析.主成分分析表明,水文因子流量(Q)、气温(T)、水位(Z)和水质因子(水温(WT)、pH、电导率(EC)、溶解氧(DO)、悬浮物(SS)、高锰酸盐指数(CODMn)、硫酸盐(SO42-)、氟化物(F-)、总硬度(T-Hard)、硝态氮(NO3--N)、总氮(TN)和硒(Se))的变化主导着研究区域水质变化;各采样点主成分得分和双因素方差分析结果显示研究区域水质因子时间变化主要呈现出季节和不同水库运行时期的差异.消落期(2-5月),T-Hard、F-、SO42-和EC是影响河流水质变化的主导因子;汛期(7-8月),Q、SS、CODMn、NO3--N、TN和Se是影响河流水质变化的主导因子;T和WT主导着汛末(9月)河流水质变化,并引起了DO等理化特性的变化;高水位运行期(12月),Cl-是影响河流水质变化的主导因子.现阶段,DO、有机污染物(CODMn)、无机盐(SO42-和F-)、营养盐类(NO3--N和TN)、类金属元素(Se)和水体的矿化程度(T-Hard)的变化主导着区域水质的变化,是三峡大坝近坝段水域水质的控制因子.方差分析表明,河流的理化特性(DO、pH和SS)、营养盐组分构成(NH3-N和NO3--N)、无机盐类(EC和Cl-)、石油类有机污染物及粪大肠菌群(FC)等指标在坝上与坝下断面存在显著性差异.气温、水温、降雨、含沙量的季节性影响因素和水库调度运行模式是影响近坝段水质时间差异的主要因子;空间差异主要受城区污染排放和三峡水库调度引起的坝上和坝下水文和水动力学条件差异影响.因此控制研究区域因人类活动等造成的外源性污染,并针对不同类污染物质的季节变化特征实施合理的水库运行方式是近坝段水质提升的关键. %X In order to explore the spatio-temporal variations of water quality in the upstream and downstream (99.9 km upstream and 63.0 km downstream of the dam, total length 162.9 km) of the Three Gorges Dam, principal component analysis and variance analysis were used to analyze the vicinity dam water quality in 2016. Principal component analysis showed that the main factors dominating the water quality changes in the study area were hydrological factors, such as discharge (Q), temperature (T), water level (Z) and water quality factors, such as water temperature (WT), dissolved oxygen (DO), suspended substance (SS), permanganate index (CODMn), sulfate (SO42-), fluoride (F-), total hardness (T-Hard), nitrate nitrogen (NO3--N), total nitrogen (TN) and selenium (Se). The principal component scores of each sampling point and two-way ANOVA showed that the time variation of water quality factors in the study area were mainly different in season and operation period of different reservoirs, and the water quality changed in reservoir drawdown period (February to May) was mainly dominated by T-Hard, F-, SO42- and electronic conductivity (EC), while the main leading factors were Q, SS, CODMn, NO3--N, TN and Se in flood season (July to August), and the water quality in the end of flood season (September) was dominated by T and WT, and caused changes in the physical and chemical properties such as DO. In addition, chloride (Cl-) was the leading factor in the period of high water level (December). At the present stage, changes in DO, organic pollutants (CODMn), inorganic salts (SO42-, F-), nutrient salts (NO3--N and TN), Se and mineralization degree of water (T-hard) dominate the changes in regional water quality and make the greatest effect to the water quality among all parameters. The analysis of variance showed that the physical and chemical characteristics (DO, pH and SS), nutrient composition (NH3-N and NO3--N), inorganic salts (EC and Cl-), petroleum organic pollutants and fecal coliform (FC) of rivers were varied significant in the upstream and downstream of the dam. The seasonal influence factors such as temperature, water temperature, rainfall, sediment concentration and reservoir operation mode were the main factors affecting the time difference of water quality near the dam. The spatial difference were mainly affected by the pollution of urban and the change of hydrological and hydrodynamical conditions by Three Gorges Reservoir operation. Therefore, controlling the exogenous pollution caused by human activities in the study area and implementing a reasonable reservoir operation mode for the seasonal variation characteristics of types of pollutants are the key to water quality improvement in the near dam section. %R 10.18307/2019.0303 %U http://www.jlakes.org/ch/reader/view_abstract.aspx %1 JIS Version 3.0.0