| With the rapid development of economy, more and more marine engineering were launched, the coastal ecological and ecosystem service function suffered great damage. As a result, many adverse effects hit economic development and human health. Based on marine ecosystem services, the impacts of the construction of Yangshan Project on marine ecosystem and the evaluation method of fishery loss were analyzed to provide reference for environment impact assessment and the standard of fishery loss assessment. Residual chlorine from cooling water of LNG project had toxic effects on marine biology. The results are as follows:1. The negative impacts of the construction of Yangshan Project on marine ecosystem were analyzed in order to learn effects of marine project on marine ecosystem services. Combined with technicology, impact factors of marine ecosystem services were screened, which mainly were suspended matter, shock wave and landfill. The suspended matter and shock wave decreased the quantities of fishery resources obviously, and consequently had effects on the function of ecosystem supply. However, the influence fell as the scope of construction was reduced, and in 2007 the fisheries quantities had upturned to the level before the construction. Accordingly, it could be suggested that the impacts of project on the supply function of marine ecosystem mainly came from its construction period. The influences during operation period were mainly the port and channel area which restricted the fishery work, and thus the fishery production decreased. In terms of the regulation function of ecosystem, little waste water and materials were discharged from project. The monitoring results showed that there was no obviously increasing nutrients in Yangshan water from 2002 to 2006. In respect of landscape, the construction took significant influence on the original sight, but it brought up some new sights such as Donghai Bridge, and the tourism income increased apparently. In terms of supporting function of ecosystem, suspended matter and shock wave influenced the amount of marine organisms (zooplankton, phytoplankton, zoobenthos )obviously during the construction, but it has recovered or is recovering now. So it means that there's little influence on marine organisms during project operate period. There's little influence on the function of spawning ground and feeding ground of Yangshan water during the construction of Yangshan Project.2. In the laboratory, it was simulated of residual chlorine emissions from cooling water of LNG project, and the experiments of toxic effects on Larimichthys crocea larval and juvenile were made. The results showed that death of larval appeared when the concentrations of residual chlorine were 0.14 mg·L-1 and 0.20 mg·L-1, while the mortality of larval was zero in other lower concentration of residual chlorine, and the mortality of juvenile fish showed no significantly correlated with residual chlorine. According to the survey in 2009, the average density of larval and juvenile fish were 8.75×106 ind.·km-2 and 5.39×103 ind.·km-2. Based on the model in EIA report, the concentrations of residual chlorine in 0.01 mg·L-1, 0.05 mg·L-1 and 0.10 mg·L-1 corresponded with the maximal diffused area 0.248km2, 0.047km2 and 0.010km2, respectively. Based on interpolation method, the mortality of larval were 0.00%, 0.00% and 6.68%, and those were 4.13%, 4.72% and 0.92% to juvenile fish, correspondingly. Combined with the evaluation formula W=D×V×M, the loss of larval and juvenile fish caused by residual chlorine discharged from LNG project were 5.84×105 ind. and 6.77×103 ind. Survey data in 2010 showed that the average density of larval and juvenile fish were 40.63×106 ind.·km-2 and 13.89×103 ind.·km-2, and it were obviously higher than those in 2009. So the results showed that residual chlorine discharged from LNG project had no significant effect of ocean fish.3. In the laboratory, it was simulated of residual chlorine emissions from cooling water of LNG project, and the experiments of toxic effects on Penaeus vannamei larval were made. The results showed that survival rate of larval were 100%, 100%, 88.89%, 61.25%, 56.25% and 20.83% when the concentrations of residual chlorine were 0.00 mg·L-1, 0.02 mg·L-1, 0.08 mg·L-1, 0.14 mg·L-1, 0.20 mg·L-1 and 0.26 mg·L-1, and the rate decreased with increasing the concentration, getting the trend-line y= -2.7257x2+3.2307x+101.24. In 2009, the average density of larval shrimp were 125.41×103 ind.·km-2. Based on the model in EIA report, the concentrations of residual chlorine in 0.01 mg·L-1, 0.05 mg·L-1 and 0.10 mg·L-1 corresponded with the maximal diffused area 0.248km2, 0.047km2 and 0.010km2, respectively. Based on interpolation method, the mortality of larval were 0.00%, 5.56% and 20.32%, correspondingly. Combined with the evaluation formula W=D×V×M, the loss of larval shrimp caused by residual chlorine discharged from LNG project were 58.23×103 ind. In 2010, the average density of larval was 9.17×103 ind.·km-2, which was lower than those in 2009. However, according to the survey data, the larval individual density of shrimp in 2010 (7.76%) was obviously lower than that in 2009 (69.38%). It can be concluded that the decrease of shrimp larval in 2010 was not caused by residual chlorine discharged from LNG project. |
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