拉林河浮游植物三种功能群分布特征及其与环境因子的关系

DISTRIBUTION CHARACTERISTICS OF THREE FUNCTIONAL GROUPS OF PHYTOPLANKTON IN LALIN RIVER AND THEIR RELATIONSHIP WITH ENVIRONMENTAL FACTORS

浮游植物是河流生态系统能量流动与信息传递的关键环节。浮游植物及其功能性状对于水体水文条件、理化特征及气候变化敏感,因此被广泛应用于水体环境监测。拉林河流域是我国北方重要稻米基地和商品粮基地,受农业面源污染严重。然而,拉林河流域浮游植物群落演替规律尚不明确,基于不同生态属性的功能群对拉林河环境的指示意义仍不清晰。于2021年春季和夏季在拉林河流域设置23个采样点对浮游植物群落进行定性定量分析。基于浮游植物功能群(functional group,FG)、生态功能群(morpho-functional group,MFG)和形态功能群(morphology-based functional group,MBFG)分析浮游植物群落演替特征。通过冗余分析(redundancy analysis,RDA)揭示驱动浮游植物群落演替的关键环境因子。结果显示,研究期间拉林河流域浮游植物群落演替明显,划分FG功能群25个,MFG功能群24个,MBFG功能群7个。FG、MFG和MBFG功能群的演替受多种环境因素共同影响,其中水温(water temperature,WT)和总氮(total nitrogen,TN)与功能群演替关系密切。经研究表明FG功能群能更好的响应拉林河流域水环境的时空异质性。相较于传统的林奈分类法,FG功能群提供了高效、简便且能反映生态信息的划分方式。在未来对于拉林河流域水生生物多样性保护及环境监测研究中,FG功能群是可靠的研究手段。

Phytoplankton play a key role in the energy flow and information transfer of riverine ecosystems.Phytoplankton are sensitive to the hydrological conditions,physicochemical conditions,and climate change of water bodies,and are therefore widely used for environmental monitoring in water bodies.Recent studies revealed that phytoplankton functiontal traits is an indicator to environmental change in river ecosystem.Lalin River basin(LRB)in NE China is an important rice and commodity grain production base in the north of China.Unfortunately,LRB has been seriously polluted with agricultural surface-sourced pollutants.However,the succession pattern of phytoplankton communities in the LRB is still unclear,and the significance of functional groups(FGs)based on different ecological attributes on the LRB environment remains unclear.Therefore,we conducted a qualitative and quantitative analysis on the phytoplankton community from 23 sampling sites in the LRB in spring and summer 2021,and analyzed the phytoplankton community succession pattern based on FGs,morpho-functional groups(MFGs)and morphology-based functional groups(MBFGs).The most important environmental factors driving the succession of phytoplankton communities were revealed in redundancy analysis.Results show that the phytoplankton communities in the LRB evolved significantly during the study period,during which 25 FGs,24 MFGs,and 7 MBFGs were classified.The succession of FGs,MFGs,and MBFGs was influenced by combination of environmental factors,among which water temperature and total nitrogen were closely related to FG succession.This study showed that the FG could better respond to the spatial and temporal heterogeneity of the water environment in the LRB.Compared with the traditional Linnaean taxonomy,FGs provide an efficient,simple,and ecologically informative way of classification.In the future,FG will be a reliable research method in the research of aquatic biodiversity conservation and environmental monitoring in LRB and other areas of the sort.