Abstract: From April 2010 to February 2011, a monthly tracking survey and monitoring was conducted on the ecological restoration project ‘returning fishery to lake’ of Dalian Lake in Shanghai, with the physical and chemical indicators of water environment before and after the implementation of the engineering project compared, aimed to assess the improvement effects of the project on the water environment. As compared with those outside the ecological restoration area, the concentrations of total phosphorous, total nitrogen, NO₃^--N, and NH₄⁺-N and the COD in the ecological restoration area decreased by 62.5%, 72.2%, 92.9%, 63.3%, and 8.9%, respectively, while the DO increased by 11.1%. In addition, the concentration of chlorophyll a and the abundance and biomass of phytoplankton in the restoration area decreased by 47.7%, 15.3%, and 48.0%, respectively. The integrated water quality identification index of the ecological restoration area was of National class Ⅲ, while that of the control point was of class Ⅳ, and the outlet water quality of the ecological restoration area was obviously better than the inlet water quality. After the implementation of the restoration project, the phytoplankton flora in the restoration area was improved, and the water ecosystem had definite self-purification capacity.

Key words: specific growth rate, priming effect,  , microbial growth strategies, r-strategists and K-strategists.