Reclamation Impacts On Sediments And Macrobenthos In Eastern Liuheng Island

At present our country coastal areas are the implementation of the new round ofmarine development strategy, to promote the development of marine economy new climax.In the development of marine economy, more land resource supply demanded, with strictfarmland protection policy, the government expanding the scale of reclamation toguarantee the construction land demand. Scientific reclamation have very important realsense for alleviating the contradiction between people and land in coastal areas andpromote the development of social economy. It can produce remarkable economic andsocial benefits. But large area reclamation activities also bring a series of serious problems,such as the destruction of ecosystem, increasing pollution of the marine environment,cause piscatorial resource failure and so on.Along with the islands of Zhoushan new area was established, the Liuheng Islandposition more clearly, Liuheng Island has taken reclamation activitiesin to solve thebottleneck problem of large scale land recent years. In order to further understand theeastern Liuheng reclamation project status about sediments and macrobenthos impactsnearby.In this paper, reclamation were investigated in eastern Liuheng, sediments andmacrobenthos were sampled during the summer of2010in Liuheng Island.Set10sediments stations and18macrobenthos stations. According to the survey results, thesediment quality, macrobenthos species composition and biodiversity evaluation, thewaters of the2006survey data as the background values are compared and analyzed,discusses the effection about the reclamation project on sediments and macrobenthos,summed up he main environment problems in the reclamation project to Liuheng islandhorizontal sediments and macrobenthos.And analysis of Liuheng Island inshore watersdevelopment and utilization status and existing problems, puts forward correspondingmeasures and suggestions.The sediment parameters standard index were less than one in2006and2010,meetwith the marine functional zone requirements.35species of macrobenthos were identifiedin2006, the average of biomass is4.01g/m2, the average of density is182ind/m2;23species of macrobenthos were identified in2010, the average of biomass is2.68g/m2, theaverage of density is31ind/m2; Compared with the two survey results showed that thesediment quality did not change significantly, comprehensive potential risk is low; Thespecies, biomass, density, diversity index and evenness have different degrees of reduction.It due to ocean engineering. Since2006, marine development activities weretaken in the area,it effected the sediment and macrobenthos, over time,the effection of thesediment and macrobenthos were obviously.The main research results are as follows:(one), After reclamation engineering builded,the sea sediment quality did not change significantly, comprehensive potential risk is low,but the need to consider the sediment accumulation effect; The average biomass ofmacrobenthos, average density and diversity index were decreased, the dominant specieswas not obvious, and by the degree of pollution.(two), discussed the relatuion between thesediment quality and macrobenthos,the significance level is not obvious, but with greatercorrelation coefficient of heavy metals.(three)，sea reclamation on benthic influencemainly has two aspects, One is the reclamation on waters have permanent occupation,which causes the benthic total loss, the influence can not be repaired; The other is causedby the diffusion of suspended substance, the effects on benthic organisms is short.