摘要
洪水过境会剧烈扰动河流受闸坝阻隔形成的相对缓流或静止水体.为了解此情景下浮游植物功能群对生境恢复的指示作用,选取典型多闸坝河流广东省茂名市黄华江(信宜段),对其洪水期间(刚过境、过境1周、过境1个月)的水质和浮游植物进行调查和分析.整个监测过程中,共鉴定出浮游植物7门80种,可归属于20个功能群.该河段浮游植物种类数、丰度和生物量在洪水刚过境时大量减少,其物种丰富度和多样性在洪水过境1周到1个月左右才得以恢复,且支流的恢复速度快于干流.洪水刚过境和过境1个月时,干流的浮游植物功能群组成存在显著差异(p<0.05),优势群落以硅藻向隐藻、绿藻转变,优势功能群则按适应经常性搅动、浑浊的水环境的类群MP、P、B向适应水体分层或静水环境的类群X2、Y演替.在此过程中水质指标浊度和悬浮物浓度显著降低、电导率显著升高,水体均处于中营养水平.冗余分析(Redundancy analysis,RDA)结果显示,对浮游植物优势功能群影响较大的环境因子有浊度、悬浮物、pH值、高锰酸盐指数、总磷、氨氮和电导率等.洪水期间闸坝对水文条件的改变也是影响浮游植物群落结构的重要因素.相比于浮游植物多样性指数的评价方法,结合水体理化因子与浮游植物功能群变化进行综合分析,在极端水文条件影响下多闸坝河流的水质及生态评价具有潜在优势.
Floods can cause a sudden dramatical change in a relatively slow flow or static water body formed by the barrier of dam.To understand the indicative role of phytoplankton functional groups in habitat restoration under the influence of flood events in continuous river barrages,the Xinyi section of Huanghua River in Maoming City,Guangdong Province,China,a typical multi-gate dam river,was selected as the research subject.The study aimed to explore the relationship between the response of phytoplankton community structure and water quality during flood events from the beginning to one month after the flood transit.Throughout the monitoring process,a total of 80 species belonging to 7 phyla of phytoplankton were identified.All identified phytoplankton species could be classified into 20 functional groups.During flood events,there was a significant decrease in the number of phytoplankton species,abundance and biomass in the Huanghua River section.However,the richness and diversity of species recovered within approximately one week to one month after the flood,and those in tributaries recovered faster than in the main stream.Significant differences were observed in the composition of phytoplankton functional groups between the main channel immediately after the flood and one month after the flood(p<0.05).The dominant community of phytoplankton showed a succession from diatoms to cryptophytes and chlorophytes while the dominant functional groups exhibited a succession pattern from codon MP,P,and B which adapt to frequently stirred up,turbid habitat to codon X2 and Y which live in almost all lentic or stratified ecosystems.In this process,the river section was indicated at the medium nutrient level,the concentration of turbidity and suspended matter concentration decreased significantly,and the concentration of electrical conductivity increased significantly at the same time.The results of redundancy analysis showed that turbidity,suspended solids,pH,permanganate index,total phosphorus,ammonia nitrogen,and conductivity were the most important environmental factors affecting the dominant functional groups of phytoplankton.In addition,the impact of dam on hydrological conditions was an important factor as well.These results suggest that compared with the use of phytoplankton diversity indexes,the comprehensive analysis combining physical and chemical factors of water bodies with changes in phytoplankton functional groups has the potential advantage for water quality and ecological assessment of multi-gate dam rivers under extreme hydrological conditions.
作者
于菲
毛宇鹏
黄志伟
曾海龙
房怀阳
林澍
付玲芳
YU Fei;MAO Yupeng;HUANG Zhiwei;ZENG Hailong;FANG Huaiyang;LIN Shu;FU Lingfang(National Key Laboratory of Water Environmental Simulation and Pollution Control,Guangdong Key Laboratory of Water and Air Pollution Control,South China Institute of Environmental Sciences,Ministry of Ecology and Environment of the People’s Republic of China,Guangzhou 510655)
出处
《环境科学学报》
北大核心
2025年第3期451-461,共11页
Acta Scientiae Circumstantiae
基金
黄华江江段大鲵和水产资源自然保护区水域生态调查专项(No.PM-hx002-202311-0537)
中央级公益性科研院所基本科研业务专项(No.PM-zx097-202406-214)。
关键词
浮游植物
群落结构
功能群
闸坝
洪水
phytoplankton
community structure
functional groups
dam
flood
