太阳山湿地浮游植物优势功能群季节演替特征及驱动因子分析

为探明太阳山湿地浮游植物优势功能群季节演替规律及其主要驱动因子,于2019年4月(春季)、7月(夏季)、10月(秋季)和2020年1月(冬季)采样分析了太阳山湿地浮游植物的种类组成、优势种、丰度、生物量及季节变化,同时测定了水环境理化因子指标,采用冗余分析方法研究了浮游植物优势功能群的优势度、丰度与水环境因子之间的关系。结果表明:太阳山湿地浮游植物可分为22个功能类群;优势功能群的季节演替和空间分异特征明显,存在一定的规律性。春、秋、冬3个季节的浮游植物以硅藻门为主,夏季以绿藻门和蓝藻门为主。春季优势功能群主要为D、C、P,以硅藻门种类为主;夏季优势功能群主要为J、Lo、TC、M、H1,以硅藻门、绿藻门、蓝藻门种类为主;秋季优势功能群主要为D、S1、MP,以硅藻门、绿藻门种类为主;冬季优势功能群主要为D、X3,以硅藻门种类为主。影响太阳山湿地浮游植物优势功能群季节演替的水环境因子有水温(WT)、pH、溶解氧(DO)、透明度(SD)、盐度(Sal)、氮磷营养元素含量、化学需氧量(COD_Cr)和高锰酸盐指数(COD_Mn)。4个湖区浮游植物优势功能群的时空差异与水环境因子密切相关,其中,西湖区浮游植物优势功能群的季节演替驱动因子为pH、DO、WT、总磷(TP),东湖区为pH、DO、WT、氮磷营养元素含量,南湖区为pH、DO、COD_Cr、五日生化需氧量(BOD₅),小南湖区为pH、DO、WT、BOD₅、COD_Cr、TP。pH、DO、WT、BOD₅、SD等水环境因子的季节差异以及TP、TN、氨氮(NH₃-N)、COD_Mn等水环境因子的湖区差异是太阳山湿地浮游植物优势功能群出现季节演替的主要原因。

Seasonal Substitution Characteristics and Driving Factors of Phytoplankton Dominant Functional Groups in Taiyangshan Wetland

In order to explore the seasonal succession characteristics and driving factors of dominant functional groups of phytoplankton in Taiyangshan wetland,the species composition,dominant species,abundance,biomass of phytoplankton and their seasonal changes in April (spring),July (summer),October (autumn) of 2019 and January (winter) of 2020 were analyzed.At the same time,the physicochemical factors of water environment were measured,and the relationship between the dominance and abundance of phytoplankton dominant functional groups and water environmental factors was studied by redundancy analysis method.The results showed that the phytoplankton of Taiyangshan wetland was divided as 22 functional groups.The seasonal succession and spatial differentiation of dominant functional groups were distinct,and there was a certain pattern in the seasonal succession of phytoplankton functional groups.The phytoplankton were mainly dominated by diatoms in spring,autumn,winter,and mainly dominated by green algae and cyanobacteria in summer.Dominant functional groups were mainly D/C/P with diatom type in spring,mainly J/Lo/TC/M/H1 with diatom,green algae and cyanobacteria type in summer,mainly D/S1/MP with diatom and green algae type in autumn,mainly D/X3 with diatom type in winter.The environmental factors that mainly influenced dominant functional groups of phytoplankton were water temperature (WT),pH,dissolved oxygen (DO),transparency (SD),salinity (Sal),nitrogen and phosphorus,chemical oxygen demand (COD_Cr) and permanganate index (COD_Mn).Spatial and temporal differences in the dominant functional groups of phytoplankton were closely related to environmental factors.The driving environmental factors of phytoplankton dominant functional groups were pH,DO,WT and total phosphorus (TP) in the western lake,which were pH,DO,WT,nitrogen and phosphorus nutrients in the eastern lake,pH,DO,COD_Cr and five days'' biochemical oxygen demand (BOD₅) in the southern lake,and pH,DO,WT,BOD₅,COD_Cr and TP in the little southern lake.The main driving environmental factors of seasonal succession of dominant functional groups of phytoplankton in Taiyangshan wetland were the differences of pH,DO,WT,BOD₅,SD in different seasons,and the differences of TP,TN,ammonia nitrogen(NH₃-N),COD_Mn concentrations of different lakes in the same season.