The Research On Ecological Environment Change Of Qingdao Marine Dumping Site

Qingdao marine dumping site, off the Jiaozhou Bay, was authorized for special dredged materials of harbors and channels in 1986. Now dumped materials amount to 5.0×107m3. Qingdao marine dumping site adjacent the mariculture area, the navigation channel and resort districts is a environment sensitive and economic development zones. The environmental impact of marine dumping attracts the most attention. So it has important theoretical and practical meaning for the sustainable development of marine resource that we should assess the influence of marine dumping.The thesis begins with collecting and analyzing a lot of investigation data from 1985 to 2003, such as water depth topography, hydrochemical , ocean current and biological survey data etc.. Then it mainly analyses the status of ecological environment and the developing tendency of seawater and sediments as well as the changing of the biological community, using Fuzzy comprehensive method, the environmental quality and ecological risk evaluation, and SPSS software etc.. The further research is performed on the effect of dumping upon the temporal and spatial distribution of pollutants, depth topography, biological community structure, including biological species, the dominant specie, biomass, and density, as well as the ensuing effects on surrounding environment.The results show that the quality change of seawater and sediment is due mainly to the contaminant contained in the dredged material. Marine dumping caused a certain degree of degradation to the quality of the seawater and sediment in the 90s., after that things are getting better. The main pollutant in seawater are Pb, Hg and the oil, and the oil, the organic matter, sulfide, Pb, Cd and Cu are main pollutants in sediment, in addition the potential ecological risk of Cd and Hg are relatively higher. Dumping have directly affected to the content of suspend solid, the structure of sediments, the water depth and the content and distribution of pollutants.Marine dumping caused a huge change to the biological communities. For example, the density of total cell number of phytoplankton have decreased greatly, and some predominant species of phytoplankton and zooplankton were disappeared.