Comparative Study On Planktonic Community Structure Between Sun Island And Songbei National Wetland Park

In this study,we examined the plankton community structure and its relationship with water environmental factors in two different types of national wetland parks in Songbei District of Harbin City.We aimed to compare the differences of plankton diversity between natural wetland and constructed wetland,and to provide basic data for wetland protection and restoration.At the same time,taking the natural wetland park as a reference,the recovery degree of the artificial wetland park that had been implemented for 8 years was compared and analyzed,which also provided a basis for the future ecological protection and later construction of the Sun Island National Wetland Park and Songbei National Wetland Park.In this study,Sun Island National Wetland Park and Songbei National Wetland Park,both located in Songbei District of Harbin City,were selected as the research sample sites.Representative areas of Sun Island National Wetland Park and Songbei National Wetland Park were selected in May(spring),July(summer)and September(autumn)of 2021 to set up sample sites,respectively.Plankton collection and water physical and chemical indexes monitoring were conducted in the middle of each month on sunny days.Twelve sampling sites were set up in the Sun Island National Wetland Park,and eight sampling sites were set up in the Songbei National Wetland Park.The composition,dominant species,abundance,biomass,and biodiversity of plankton species in the two plots were investigated and compared.The main results are as follows:(1)A total of 167 species,68 genera and 8 phyla,were found in the two national wetland parks.Among them,121 species were found in Taiyang Island National Wetland Park,and 96species were found in Songbei National Wetland Park.Chlorophyta and diatoms accounted for a large proportion in the two national wetland parks.There was little difference in the dominant species of phytoplankton between Taiyangdao National Wetland Park and Songbei National Wetland Park,with the common dominant species of the two plots.Cyclotella meneghiniana,Synedra acus,Ankistrodesmus falcatus,etc.A total of 76 zooplankton species were found,among which rotifers were the most abundant.A total of 45 species were found in Sun Island National Wetland Park,and 31 species were found in Songbei National Wetland Park.Based on the composition of zooplankton species in Taiyang Island National Wetland Park and Songbei National Wetland Park,it was found that protozoa and rotifera were the main components of zooplankton communities.The number of zooplankton species in each season was summer,spring and autumn.Compared with Songbei National Wetland Park,there were more dominant species in Taiyangdao National Wetland Park with smaller dominance,and the community structure was relatively complex and stable.The distribution ranges of abundance and biomass in the Sun Island National Wetland Park were as follows:the abundance ranged from21.35×10~4/L to 89.36×10~4/L,with an average abundance of summer>spring>autumn.Biomass varied from 0.63mg/L to 19.35 mg/L,with average biomass in summer>autumn>spring.The annual abundance of phytoplankton in Songbei National Wetland Park ranged from13.21×10~4/L to 57.23×10~4/L.Biomass varied from 0.26mg/L to 16.26 mg/L,with an order of summer>spring>autumn.(2)There was a small difference in phytoplankton biodiversity between Sun Island National Wetland Park and Songbei National Wetland Park.The average Shannon-Wiener diversity index and Margalef richness index of phytoplankton in Sun Island National Wetland Park were the highest(3.96±0.05 and 4.71±0.13,respectively).3.04±0.44 and 4.03±0.02 in Songbei National Wetland Park,respectively.Shannon-Wiener diversity index and Margalef richness index of zooplankton in Sun Island National Wetland Park were the highest(2.62±0.15 and 3.78±0.44,respectively).In Songbei National Wetland Park,the two indices were 2.56±0.09 and 2.09±0.28,respectively.The results of biodiversity index showed that the community composition of Sun Island National Wetland Park was more diverse and complicated.(3)In this study,we compared the phytoplankton community structure in Taiyang Island National Wetland Park and Songbei National Wetland Park using non-metric multidimensional scale analysis.The results showed that the phytoplankton community in Taiyang Island National Wetland Park was significantly different from that in Songbei National Wetland Park.The phytoplankton communities of the two sites could be distinguished from each other in each season.The results of non-metric multidimensional scale analysis of zooplankton were consistent in the two wetland parks.Compared with the Sun Island National Wetland Park,the differences of zooplankton communities among the sampling sites in Songbei National Wetland Park were small,especially in summer.(4)According to the RDA analysis of zooplankton community and water environmental factors in Songbei National Wetland Park,water temperature,TP,TN and CODcr were the main influencing factors of water environment.According to the RDA analysis of phytoplankton community and water environment factors in the Sun Island National Wetland Park,water temperature,TP and p H were the main influencing factors of water environment.Results of redundancy analysis showed that DO,TN,CODcr,and water temperature had significant effects on zooplankton community in Songbei National Wetland Park.The RDA analysis of zooplankton community and water environmental factors in Sunshine Island National Wetland Park showed that water temperature,p H,TN and TP were the main environmental factors.