Characteristics of the community structure of phytoplankton and its relationship with environmental factors in three typical types of aquaculture ponds around Honghu area
The changes in phytoplankton community structure and abundance in aquaculture water can indicate the state of water quality.During the aquaculture process,tracking, monitoring and regulation of phytoplankton can promote the stable and efficient operation of aquaculture systems, and facilitate the smooth development of aquaculture activities.To explore phytoplankton community structure and dynamics in different aquaculture ponds,including Eriocheir sinensis, Procambarus clarkii and fish(conventional freshwater fish), we conducted the quarterly survey in 2019-2020 around the Honghu Lake.Seasonal changes in phytoplankton species composi-tion,cell density, biomass aquaculture ponds and diversity between the three aquaculture ponds of were ana-lyzed.Results are as follows:(1) A total of 132 phytoplankton species belonging to 96 genera and seven phyla were detected.The overall phytoplankton biomass and cell density trend was fish ponds>crab ponds>crayfish ponds.The average cell densities were 1.06×108, 6.04×107 and 2.35×107cell/L, and the average biomass (chlorophyll a) were 94.82, 65.95 and 31.15μg/L, respectively.(2) The results expose that different culti-vated-animals significantly affected phytoplankton community composition(P= 0.001) and the community e-volution exhibits a marked seasonality.The phytoplankton community composition of crab ponds was similar to crayfish ponds in spring and summer,whereas it' s more similar to fish ponds in autumn and winter.For cray-fish ponds and crab ponds,the lowest Shannon-Wiener index and Pielou index were observed in the harvest season(summer for crayfish and autumn for crab).(3) The redundancy analysis(RDA) results showed that temperature(Temp), dissolved oxygen(DO), pH and dissolved total phosphorus(DTP) were significantly correlated with phytoplankton species composition in aquaculture ponds.The results of multivariable linear re-gression models demonstrate that TN and cultivated animals were the main factors explaining the changes in phytoplankton biomass in spring and autumn.In contrast, they were TP, DTP and NH4+-N in the winter sea-son.The differences in the breeding cycle and management activities were the main reasons for the significant differences in phytoplankton community structure.This study revealed the phytoplankton community character-istics of fish,crayfish and crab ponds, and identified the main environmental factors affecting the structure and abundance of phytoplankton, which provided a reference for the scientific management of aquaculture ponds.In view of the detection of algal bloom-inducing species in the dominant phytoplankton groups during the drainage season,it is suggested to strengthen the monitoring of tailwater in aquaculture to prejudge the potential impact of provenance migration on adjacent waters.
维普
万方数据
