【摘要】 澜沧江梯级水库群建设对流域水生态环境产生了一定的影响,将流域水体划分为自然河道段和水库段.为了探究梯级水库建设后澜沧江流域不同类型水体氮、磷营养盐和叶绿素a浓度的空间变化规律以及叶绿素a浓度与环境因子之间的关系,于2017年6月对澜沧江流域生态环境进行了调查分析.结果表明,澜沧江水体总氮质量浓度变化范围为0. 37～1. 22mg·L^-1,均值为0. 70 mg·L^-1;总磷质量浓度变化范围0. 01～0. 19 mg·L^-1,均值为0. 04 mg·L^-1.单因素ANOVA分析表明,总氮空间差异显著,表现为支流段>水库段>自然河道段;但总磷没有明显的空间差异.澜沧江水库段水体叶绿素a浓度变化范围为2. 6～10. 2μg·L^-1,均值为5. 8μg·L^-1. Pearson相关性分析结果显示,水体叶绿素a浓度与总磷浓度、水温和真光层与混合层之比(Z_eu/Z_mix)等具有显著相关性,其中与Z_eu/Z_mix的相关性最高（R²=0. 689,P=0. 001）,表明水温分层驱动下的Z_eu/Z_mix是影响澜沧江水库水体中浮游植物生长的关键性指标.更多还原

【Abstract】 Construction of cascade reservoirs in Lancang River had a certain influence on the ecological water environment of the basin,dividing the water into natural reaches and reservoir reaches. To explore the impact of the cascade reservoirs on the ecological environment,the nutrient and the chlorophyll a distribution data were measured in the natural reaches,reservoir reaches,and tributaries in June 2017. The results showed that the TN ranged from 0. 37 to 1. 22 mg·L^-1,with an average of 0. 70 mg·L^-1,and the TP ranged from 0. 01 to 0. 19 mg·L^-1,with an average of 0. 04 mg·L^-1. One-way ANOVA analysis showed significant spatial differences in the TN,with the TN concentration following the order tributaries > reservior reaches > natural reaches. However,the TP concentration did not show a significant trend. The chlorophyll a concentration varied from 2. 6 to 10. 2 μg·L^-1,with a mean of 5. 8μg·L^-1. Pearson correlation analysis showed significant relationships between the chlorophyll a concentration and the TP,water temperature,and Z_eu/Z_mix. The relationship between chlorophyll a and Z_eu/Z_mixwas particularly significant,which indicated the Z_eu/Z_mixcaused by thermal stratification may be the key factor influencing the growth of phytoplankton.更多还原