Investigation on hydrobios resource evolution in Bohu lake ecosystem restoration area
The investigation on hydrobios resource evolution in 4 000 hm2 Bohu lake ecosystem restoration area was conducted from 16th,August 2007 to 3rd-5th,August 2010 in Susong county.The result showed that after three years,phytoplankton in the area increased by 3 genera 6 species which were 52.24×104 L-1 in cell numbers and 0.3708 mg?L-1 in biomass.Zooplankton in the area increased by 11 genera 22 species which were 11.031 mg?L-1 in biomass.Zoobenthos increased by 4 families 11 genera 13 species and the density increased by 21.2 ind?m-2.Because the average density and biomass of snails decreased by 89% and 90.5% respectively,the total biomass of Zoobenthos dropped by 94.8%.The average biomass of submerged plant increased slightly only at Cross section I,but decreased at Cross section II and III.In summary,the raising of water level in Bohu lake eco-system restoration area was the main reason of the significant change on population structure and resource of hy-drobios.