Abstract:

Fish community structure were analyzed based on the investigation in Gezhouba Reservoir during May to June and November to December,2009-2010.The catches in the whole investigation consisted of 55 species belonging to 10 families,6 orders,and most were cyprinids,accounting for 673% of the total species number.There were no significant differences between the two sampling seasons in diversity and community structure.〖WTBX〗Hemiculter bleekeri,Parabramis pekinensis,Hemiculter leucisculus,Saurogobio dabryiwere〖WTBZ〗 were the most abundant species,with their average body length as 914±157 mm,2197±353 mm,867±160 mm and 1025±223 mm，respectively.With regard to ecological groups,lentic species and riverlake migratory species were dominated in the reservoir,accounting for 502% and 465%,respectively.Abundance biomass comparison curve showed that the fish community of Gezhouba Reservoir was affected moderately.Based on the ecological group analysis,the fish community structure of Gezhouba Reservoir was similar to that of the Three Gorges Reservoir,and obviously different from that in the previous catchment area of Gezhouba Dam and the section of Yichang before the construction of Gezhouba Dam in the Yangtze River.Altered hydrodynamics had a significant impact on fish community structure