赤水河流域秋季底栖硅藻群落结构特征及水质评价  

Autumn Benthic Diatom Community Structure and Water Quality Assessment in the Chishui River Basin

作　　者：谢纯林 王涛 胡俊杰 阎春兰[1] 裴国凤[1] XIE Chun-lin;WANG Tao;HU Jun-jie;YAN Chun-lan;PEI Guo-feng(College of Life Sciences,South-Central University for Nationalities,Wuhan 430074,P.R.China)

机构地区：[1]中南民族大学生命科学学院,湖北武汉430074

出　　处：《水生态学杂志》2022年第6期43-50,共8页Journal of Hydroecology

基　　金：国家自然科学基金(30970550);中央高校基本科研业务专项基金(CZY20002)。

摘　　要：为研究赤水河流域秋季底栖硅藻群落特征及水质状况,2019年秋季(9月)进行了赤水河流域上、中、下游36个代表性样点的水体理化指标测定和底栖硅藻采集鉴定,应用硅藻指数评价其水质状况。结果表明,秋季赤水河流域的电导率波动较大,上游高于下游;扎西河、铜车河和倒流河等上游支流样点的总氮(1.56 mg/L)和总磷(0.05 mg/L)显著高于下游样点(1.23 mg/L和0.02 mg/L)。共鉴定出底栖硅藻29属138种,底栖硅藻群落结构具有明显的空间异质性,上游样点优势种扁圆卵形藻多孔变种(Cocconeis placentula var. euglypta)丰度为18.90%,变异直链藻(Melosira varians)在威信县河段的丰度高达48.62%;中游桐梓河样点的优势种为三角帆头曲丝藻(Achnanthidium latecephalum)和谷皮菱形藻(Nitzschia palea);下游样点的主要优势种为极细微曲壳藻(Achnanthes minutissima),其丰度为9.18%。下游底栖硅藻群落香农-威纳多样性指数和Pielou均匀度指数的稳定性高于中、上游。典型对应分析(Canonical Correspondence Analysis, CCA)显示,影响赤水河流域底栖硅藻群落的主要环境因子是可溶活性磷(SRP)和总氮(TN)。营养硅藻指数(Trophic Diatom Index, TDI)和欧盟硅藻指数(European Economic Community Index, CEE)评价结果表明,55.6%的样点水质在“中等”以上,33.3%的样点水质为“较差”,11.1%的样点水质为“极差”,赤水河流域整体水质评价为“中等”。In this study, we investigated the characteristics of the autumn benthic diatom community in the Chishui River basin, and the diatom indices were then used to evaluate the water quality. In September 2019, the determination of water environmental factors and benthic diatom sampling were carried out at 36 representative sampling sites of the upper, middle and lower Chishui River and its tributaries. Results show that the conductivity at different sampling sites fluctuated greatly in autumn, and conductivity upstream was higher than downstream. The concentrations of total nitrogen(1.56 mg/L) and total phosphorus(0.05 mg/L) in the upstream tributaries(Zhaxi River, Tongche River and Daoliu River) were significantly higher than those in the downstream tributaries(1.23 and 0.02 mg/L). A total of 138 benthic diatom species belonging to 29 genera were identified during study period. The community structure of benthic diatoms in the Chishui River basin showed obvious spatial heterogeneity. Abundances of the dominant species Cocconeis placentula var. euglypta accounted for 18.90% of the total abundance in the upper stream, and the abundance percentage of Melosira variants in the section of Weixin county was above48.62%. The dominant species in Tongzi River of the middle reaches were Achnanthidium latecephalum and Nitzschia palea, and Achnanthes minutissima was the primary dominant species in the downstream,with an abundance of 9.18%. The Shannon-Wiener diversity and Pielou evenness indices of the benthic diatom community in the lower reaches showed higher stability than in the middle and upper reaches. Canonical correspondence analysis(CCA) showed that the primary environmental factors affecting the benthic diatom community in Chishui River basin were soluble active phosphorus and total nitrogen. The water quality grade of the all sampling sites was evaluated based on the trophic diatom index(TDI) and European Economic Community(CEE) index and the results show that 55.6% of the total sampling sites were above medium, 33.3%

关 键 词：底栖硅藻 多样性指数 硅藻指数 水质评价 赤水河 

分 类 号：X826[环境科学与工程—环境工程]