Issues and Challenges for the Study of the Interconnected River System Network
河湖水系连通研究的若干问题与挑战

The issue of sustainable water resources has been receiving much attention for years. With the development of economy and society in China, increasing requirements on water resources will necessitate a strategic shift. Being the new strategy of China, the Interconnected River System Network (IRSN) plan will play a significant role in water resources management in the future. To that end, it is urgent to prompt the research on the theoretical and technology system. Nowadays, studies on IRSN are more loosely scattered and have not been developed into a systemic and scientific theory system. Within IRSN, three major functions will be realized, i.e., increasing water resources allocation, improving river health, and enhancing flood and drought control. IRSN is a pan-regional concept, with different scales showing different characteristics. In terms of reality of water resources exploitation and protection in China, the authors stated in the paper that the research on IRSN can be essentially divided into three levels, i.e., national, regional, and basin levels. Differences are highlighted at each scale, i.e., 1) at the national scale, it primarily focuses on regional differences and how to make sustainable use of water resources, and coordinate the relationships among resources, society, economy and the environment. This will greatly promote the national and regional development; 2) at the regional scale, according to the functional position, comparative advantages, and water system characters of the region, it will contribute to rational water resources allocation, adapting to productive layout, and ultimately realize sustainable development of the region; and 3) at the river basin scale, the principle is the integration of the interest of every user among different reaches, and the development of nature and human within the whole river basin, with the aim to ultimately realize the sustainable water resource use, the environmental health, and sustainable development of economic society at the basin level. In the changing environment, there will be a series of challenges in the research, e.g., 1) how to match best between the distribution of river systems, and the eco-social layout. This is an effective measure of solving water shortages and ensuring stable economic development, and also the key point and great challenge of the IRSN; 2) uncertainty of climate change and the effects on IRSN. In particular, increasing extreme events will impose a big challenge for flood and drought control of the IRSN; and 3) interdisciplinary and comprehensive research. Due to the complexity of the system, the research on the IRSN will involve interdisciplinary theory, which is also a challenge for the researchers.