Evolution of the relationship between the Yangtze River and its connected lakes, its impacts on river and lake ecosystems and the potential controlling strategies

(2012CB417000)

PI: Prof. SHEN Ji

2012.1-2016.12

Poyang Lake and Dongting Lake are naturally connected with the Yangtze River. The long-term established relations of water and sediment exchange benefit both the river and lakes. The relationship is of great importance in flood control, water resources supply, water environment and aquatic ecological safety for the middle and lower reaches of the Yangtze River. Its maintenance can safeguard regional economic and social sustainable development. In recent decades, the relationship between the Yangtze River and its connected lakes has significantly affected by the various types of water conservancy projects. Numerous environmental problems began to emerge in water system of the middle Yangtze River, e.g. "heavy flooding under low intensity of rainfall”, the seasonal shortage of water resources, the deterioration of water quality and eutrophication in the lakes, the ecological degradation of wetlands. The complicated water problems caused the controversy over the Three Gorges Project. The linkages underlying these issues have been widely discussed and attracted the attention of the government, society and academia. Therefore, it is urgent for China to study the impact of the Three Gorges Project on the relationship between the Yangtze River and its connected lakes and its ecological effects of water environment, and thus to propose control strategies and recommendations to optimize the river-lake relationship and benefit both the Yangtze Rivers and its connected lakes.

The project aims to address three key scientific questions: 1) to clarify the evolution of river-lake interaction in the middle Yangtze River and the influence mechanism of major water conservancy project on the river-lake interaction; 2) to understand the response of lake hydrology, water environment and aquatic ecosystems to the river-lake relationship; 3) to construct the theory and methodology for the assessment of the river-lake health, and the controlling strategies. The project focuses on four main topics: the evolution and mechanisms of the river-lake interaction in the middle Yangtze River; the effects of the Three Gorges Project on the water and sediment exchanges between the Yangtze river and its connected lakes; the response of the lake hydrology, water environment and water ecology to the change of the river-lake interaction; the regulation principle and countermeasures for optimizing the relationship between the Yangtze river and its connected lakes.

The objectives of the project are to provide a scientific basis for the protection of water security for the middle reaches of the Yangtze River, including: 1) to identify the evolution of the river–lake relationship in the middle reaches of the Yangtze River, thus to reveal the interacting between the water and sediment transport and topographic changes; 2) to clarify the changes of river-lake interactions and its influence on lake environment and ecology under the operations of the major water conservancy projects; 3) to develop the health assessment theory and methodology for optimizing the lake ecology; 4) to predict the effects of Three Gorges Project on the water and sediment exchanges between the Yangtze River and its linked rivers, hence to predict the changing trend of lake hydrology, water environment and aquatic ecosystem evolution; and 5) finally to seek the countermeasures for optimizing the river-lake relationship combining the integrated controlling of the major water conservancy projects.

The project is composed of six subjects : 1) the evolution of river-lake relationship in the middle reaches of the Yangtze River; 2) the impact of Three Gorges Project on the water and sediment exchange between the Yangtze river and its linked lakes; 3) the hydrological response to the changes of the river-lake interaction; 4) environmental effects of the changes of the river-lake interaction; 5) the response of lake aquatic ecology and the wetland ecosystem to the change of the river-lake interaction; and 6) the optimized controlling and countermeasures to river-lake health in the middle reaches of the Yangtze River.

Evolution of the relationship between the Yangtze River and its connected lakes, its impacts on river and lake ecosystems and the potential controlling strategies

(2012CB417000)

PI: Prof. YANG Guishan

2012.1-2016.12

Poyang Lake and Dongting Lake are naturally connected with the Yangtze River. The long-term established relations of water and sediment exchange benefit both the river and lakes. The relationship is of great importance in flood control, water resources supply, water environment and aquatic ecological safety for the middle and lower reaches of the Yangtze River. Its maintenance can safeguard regional economic and social sustainable development. In recent decades, the relationship between the Yangtze River and its connected lakes has significantly affected by the various types of water conservancy projects. Numerous environmental problems began to emerge in water system of the middle Yangtze River, e.g. "heavy flooding under low intensity of rainfall”, the seasonal shortage of water resources, the deterioration of water quality and eutrophication in the lakes, the ecological degradation of wetlands. The complicated water problems caused the controversy over the Three Gorges Project. The linkages underlying these issues have been widely discussed and attracted the attention of the government, society and academia. Therefore, it is urgent for China to study the impact of the Three Gorges Project on the relationship between the Yangtze River and its connected lakes and its ecological effects of water environment, and thus to propose control strategies and recommendations to optimize the river-lake relationship and benefit both the Yangtze Rivers and its connected lakes.

The project aims to address three key scientific questions: 1) to clarify the evolution of river-lake interaction in the middle Yangtze River and the influence mechanism of major water conservancy project on the river-lake interaction; 2) to understand the response of lake hydrology, water environment and aquatic ecosystems to the river-lake relationship; 3) to construct the theory and methodology for the assessment of the river-lake health, and the controlling strategies. The project focuses on four main topics: the evolution and mechanisms of the river-lake interaction in the middle Yangtze River; the effects of the Three Gorges Project on the water and sediment exchanges between the Yangtze river and its connected lakes; the response of the lake hydrology, water environment and water ecology to the change of the river-lake interaction; the regulation principle and countermeasures for optimizing the relationship between the Yangtze river and its connected lakes.

The objectives of the project are to provide a scientific basis for the protection of water security for the middle reaches of the Yangtze River, including: 1) to identify the evolution of the river–lake relationship in the middle reaches of the Yangtze River, thus to reveal the interacting between the water and sediment transport and topographic changes; 2) to clarify the changes of river-lake interactions and its influence on lake environment and ecology under the operations of the major water conservancy projects; 3) to develop the health assessment theory and methodology for optimizing the lake ecology; 4) to predict the effects of Three Gorges Project on the water and sediment exchanges between the Yangtze River and its linked rivers, hence to predict the changing trend of lake hydrology, water environment and aquatic ecosystem evolution; and 5) finally to seek the countermeasures for optimizing the river-lake relationship combining the integrated controlling of the major water conservancy projects.

The project is composed of six subjects : 1) the evolution of river-lake relationship in the middle reaches of the Yangtze River; 2) the impact of Three Gorges Project on the water and sediment exchange between the Yangtze river and its linked lakes; 3) the hydrological response to the changes of the river-lake interaction; 4) environmental effects of the changes of the river-lake interaction; 5) the response of lake aquatic ecology and the wetland ecosystem to the change of the river-lake interaction; and 6) the optimized controlling and countermeasures to river-lake health in the middle reaches of the Yangtze River.