Community Structure of Phytoplankton in Pond Industrial Eco-aquaculture System for Megalobrama amblycephala

In order to find out the change pattern of phytoplankton community structure in pond industrial eco-aquaculture system and explain its ecological mechanism,tests were carried out using Megalobrama amblycephala as aquaculture species with two stocking densities.Shannon-Wiener diversity index and Pielou uniformity index were used to study the phytoplankton community structure in aquaculture area( including low stocking density aquaculture area and high stocking density aquaculture area),inlet area,outlet area,purification area,recirculation area,back area of the pond industrial eco-aquaculture system.The results showed that a total of 92 species of 5 phyla were identified,including 46 species of Chlorophyta,15 species of Cyanophyta,15 species of Euglenophyta,10 species of Bacillariophyta,5 species of Cryptophyta,and 1 species of Pyrrophyta.The numbers of phytoplankton species,biodiversity indexes,uniformity indexes,Chlorophyta biomass and its proportion in total phytoplankton followed the order of inlet area,purification area,recirculation area,back area > low stocking area > high stocking area > outlet area.The total biomass of phytoplankton,Cyanophyta biomass and its proportion in total phytoplankton followed the order of inlet area,purification area,recirculation area,back area < low stocking area < high stocking area < outlet area.However,all these parameters showed no significant differences or change rules among inlet area,purification area,recirculation area,back area.It could be concluded according to the biodiversity that the water quality in outlet area was at middle pollution level,the water quality in high stocking area was in light pollution level,and the water quality in other 5 areas were at clean level,which suggested that the water quality was in good states except that in outlet area,and the pond industrial eco-aquaculture system functioned well.