During the past century, the number and scale of reservoirs worldwide has grown substantially to meet the demand for water and hydropower arising from increased population, industrialization, and urbanization. This is particularly the case in China, where reservoir construction increased rapidly after the Chinese economic reform and the introduction of open-door policies. On average, 4.4 large reservoirs with a capacity greater than 0.1 km3 were constructed per annum during the 1970s–1990s. This average reached 11.8 such reservoirs per annum in the 2000s. Considering the adverse impact of dams on rivers and riparian communities, various environmentalists and non-governmental organizations in China have begun to protest against the construction of dams. Now China’s policy on dams is at a crossroads: Removal or further construction? In this paper, we systematically assess the construction of reservoirs in China and discuss the benefits and drawbacks of large-scale reservoir projects on several major rivers in China: The Yangtze River, the Yellow River and the Mekong River. Lastly, we provide a perspective on the future of reservoir development in China, taking into account natural conditions, renewable hydropower resources, and greenhouse gas emissions.
Global climate change is significant, and the spatiotemporal variations of precipitation associated with it are pronounced. Based on the daily precipitation data from 10 weather stations located from southeast to northwest across China from 1961–2017, the Mann–Kendall trend test was generally applied to analyze the spatiotemporal variations of precipitation. The factors influencing the precipitation changes were investigated. The results revealed that (1) the annual, summer, and winter rainfall amount (RA) exhibited increasing rates of 16.36, 12.31, and 2.49 mm/10 year, respectively. The change rates of annual rainfall days (RD) were 2.68 day/10 year in the northwest region and −1.88 day/10 year in the southeast. The annual and seasonal daily precipitation on rainy days (RP) exhibited an increasing trend. (2) All of the RA, RD, and RP values initially increased, then decreased, and then slightly increased from Southeast to Northwest China. These results proved that the RA increased with the increase of light rain in Northwest China and heavy rain in Southeast China. In addition, changes in the monsoon have altered the rate at which RA, RD, and RP vary with distance from the sea. These findings may help to provide suggestions for the rational spatial utilization of water resources in China.