Environmental Impact And Recovery At The Marine Dumping Site For Long-term Dumping Dredged Material In The Southeast Of The Neilingding Island, Zhujiang Estuary

The increasing amount of sediments arising from dredge and other sources and its consequent disposal has been one of the major environmental problems in Zhujiang estuary.During the late 1980s and 1990s of the past century, dredged material was dumped in the marine dumping ground in the Southeast of the Neilingding island, Zhujiang estuary.The environmental impact and recovery associated with the long and uninterrupted disposal of large volumes of moderately contaminated dredged material from the port of Shenzhen city was studied at nearby dumping sites in the Southeast of the Neilingding island, Zhujiang estuary. This thesis is based on the study to the Neilingding Island, Zhujiang estuary. The goal of this study was to determe the impact of dredged materials dumping on the submarine environment at a long period. Based on a great deal of observed data and information obtained from the marine dumping ground in the Southeast of the Neilingding island since 1995, the environment change in the Zhujiang estuary is studied by principal component analysis.The main results achived are as follows:(1)The depth of this dumping ground decrease from 1989 to 1998. The main reason which the area becomes shallow is a great of dredged material dumped in this area.(2) The aquatic environment quality shows a downtrend from 1995 to 2005. The soluble phosphate and dissolved inorganic nitrogen are the main pollutants in this area. A large volume of dredge materials dumped shows no significant impact on the marine water environment along the dumping site, otherwise a possibly important contribution to the increase of the soluble phosphate in the seawater.(3) The surface sediment environment quality shows a uptrend from 1995 to...