云南省红河流域浮游植物多样性及水质季节动态研究

Dynamics of phytoplankton diversity and water quality evaluation of Hong River during seasons

【目的】了解云南省红河流域浮游植物多样性及水质季节动态.【方法】以云南省红河流域为例,连续2a采用定点实地调查和水质采样相结合的方法研究了不同季节(春季、夏季、秋季和冬季)水质变化(全氮TN、全磷TP、生物耗氧量BOD5和化学耗氧量CODcr)及浮游植物多样性分布状况.【结果】(1)红河流域主要浮游植物种类为绿藻门和硅藻门,不同浮游植物细胞密度和丰度随季节均呈现一致的变化规律,夏季和秋季显著高于春季和冬季,局部有所波动.(2)红河流域浮游植物Shannon-Wiener多样性指数(H)、Pielou均匀度指数(JP)、Margalef种类丰富度指数(S)随季节呈"V"字型变化规律,在春季和冬季达到最高,夏季和秋季较低;不同指数所判定的污染类型不相一致.(3)红河流域水质季节性变化较为明显,水体透明度、水温、pH,TN,TP,BOD5和CODcr质量浓度呈一致的变化规律,在夏季和秋季最高,春季和冬季较低.(4)应用灰关联分析评价红河流域水质类别,呈现不同季节水质与《标准》中的Ⅰ类水质的关联度最大,分别为0.725,0.836,0.814,0.781,在不同季节里水质等级均为Ⅰ类.【结论】不同季节红河流域浮游植物多样性均与水体透明度呈极显著的负相关(P<0.01),影响春季和冬季浮游植物多样性的主要因素为TN质量浓度、TP质量浓度,影响夏季和秋季浮游植物多样性的主要因素为TN质量浓度、TP质量浓度、BOD5浓度和CODcr浓度.综合分析表明:红河流域春季和冬季水质状况较好,夏季和秋季水质状况较差.

【Objective】To understand the dynamics of phytoplankton diversity and water quality of Hong River during seasons.【Method】On the basis of field investigation and laboratory analysis of Hong River,a survey of monitoring the contamination levels of water quality（TN,TP,BOD5,and CODcr）and phytoplankton diversity was conducted in different seasons from 2014 to 2015,and combined with biological diversity index method and correlation analysis to study the relationship between phytoplankton diversity and environmental factors.【Result】（1）The major phytoplankton were Bacillariophyt and Chlorophyta,and there was great seasonal variation in phytoplankton which increased and decreased with local fluctuated.（2）The Shannon-wiener diversity index（H）,evenness index（JP）and richness index（S）first increased and then decreased with the change of season,which showed summer and autumn were higher than spring and winter.Different index to judge the type of pollution was not consistent.（3）The water quality temperature,pH,TN,TP,BOD5 and CODcrfirstly increased and then decreased with the change of season,which showed summer and autumn were higher than spring and winter,while water temperature had the different trend which showed a ＂ V＂ trend.（4）Gray relational analysis indicated that the relational degree was closed to level I of the graded environmental quality standards.The calculated values of relational degree were 0.725,0.836,0.814,0.781 in different seasons,and that the water quality was level I.【Conclusion】Correlation analysis shows that the transparency is significantly negative correlation with phytoplankton diversity（P〈0.01）,which shows that transparency reflects the phytoplankton diversity and the status of the water quality of Hong River.TN and TP concentration are the main influencing factors of phytoplankton diversity in spring and winter,while the TN,TP,BOD5 and CODcr concentration are the main influencing factors of phytoplankton diversity in summer and autumn.It is also suggested summer and autumn pollution level is higher than that of spring and winter.