This project belongs to the field of marine technology. In order to ensure the shipping, water supply and ecological security of Shanghai City, a very large estuarine city, in response to issues such as the dumping of huge amounts of dredged material in the Yangtze River estuary, salt tide intrusion and the construction of a large number of marine engineering projects, the project team has established a marine public welfare project, the National Natural Science Foundation of China, Shanghai City 908 Special Project, Shanghai City Financial Project and many years of operational projects of the Donghai Branch, the project has systematically targeted the selection and capacity assessment of marine dumping areas in the Yangtze River estuary, salt-tide intrusion monitoring and early warning, Large-scale offshore engineering projects (groups) have carried out innovative research on technologies such as quantitative assessment of marine ecological losses and ecological restoration, and have achieved many theoretical and technological breakthroughs.
The main technological innovation contents and characteristics include:
(1) Aiming at the huge amount of dredged material dumped in the Yangtze River Estuary (about 80 million cubic meters) every year, the dredging intensity is high (About 10 million cubic meters per month), and the tidal current in the sea area is complex and involves technical problems such as many environmentally sensitive areas. For the first time, the project comprehensively uses physical models, numerical simulations, and neutron-activated tracer sand and other technologies to solve the problem of the Yangtze River Estuary deepwater channel. Key technical problems in setting up dumping areas within the embankment, and established for the first time my country's dumping-scouring and silting capacity assessment method, systematically integrated marine dumping area selection technology, and formulated my country's marine dumping area selection technical standards. The overcoming of the above-mentioned problems has broken through the previous technical limitation of having to stay away from the channel for dumping area selection, effectively guaranteed the huge dredging needs of the Yangtze River Estuary deepwater channel, and solved the optimization technology for dumping operations.
(2) In view of the complex topography and hydrodynamic environment of the third-level branching and four mouths of the Yangtze River Estuary, which makes it difficult to carry out refined prediction of salt-tide intrusion, the project established a dynamic monitoring network composed of dynamic sections, fixed stations and buoy stations, optimized and improved the three-dimensional ECOM-si hydrodynamic numerical model, and used the non-orthogonal curve refined grid method to establish a salt-tide intrusion statistical model of fixed-point salinity, runoff and tide range. An operational numerical prediction system for salt-tide intrusion in the Yangtze River Estuary has been established.
(3) Aiming at the problem that the construction of large-scale ocean projects (groups) in the estuary is located in complex environmental factors and concentrated sensitive areas, it is impossible to carry out targeted, systematic and quantitative evaluation. The project carried out research taking the first phase of the Yangtze River Estuary Deepwater Channel Project and the Yangshan Engineering Group as examples, and established for the first time an evaluation method and indicator system for the project construction on the habitat fragmentation of estuarine water bodies; using the fixed integral theory, a quantitative assessment of the loss of food organisms was established for the first time. The evaluation model has formed a bait biological assessment technology and solved the evaluation problem of the impact of large-scale marine projects on the ecological service functions of plankton.
Application and promotion status: Through long-term commercial application and promotion, the results have provided a strong guarantee for Shanghai City's shipping, water supply and ecological security, and have achieved significant social, economic and ecological benefits. (1) The dumping area selection technology has only selected 7 dumping areas and 4 mud blowing areas in the Yangtze River Estuary area, processing a total of 652.34 million square meters of dredged soil, saving 564 million yuan, adding 74,500 acres of new land to Shanghai City, effectively ensuring the construction of an international shipping center. (2) The Yangtze River Estuary salt-tide intrusion monitoring and early warning technology has been commercialized and linked with the Shanghai City Water Affairs Bureau and the Shanghai City Water Supply Dispatch Center. More than 300 forecasts have been issued, with a 24-hour forecast accuracy rate of 95.1%, ensuring the drinking water safety of more than 20 million people in Shanghai City. (3) Large-scale ocean engineering groups have applied quantitative assessment of marine ecological losses and ecological restoration technologies in the Shanghai City Oceanic Administration and the East China Sea Branch, effectively improving the management department's ability to supervise marine projects, and at the same time effectively directly guiding the "State Oceanic Administration Sea Area Utilization Project-Yangshan Port Sea Area Marine Ecological Environment Protection and Restoration Project", ensuring the ecological security of the Yangtze River Estuary.
During the implementation of the project, the CCP obtained 3 software copyrights, issued 4 national industry standards, published 67 papers (including 2 SCI/EI), and published 5 monographs. After novelty search and expert appraisal, the results have generally reached the international advanced level, and some results have reached the international leading level.