Spatial-temporal distribution and variation characteristics of water resources in China during 1956—2016

To map the evolution of water resources in China and to scientifically and rationally formulate adaptive water resources management policies, this study used data from the third national water resources investigation and evaluation to calculate and analyze the amount of water resources at the national and water resources district and province levels from 1956 to 2016. We also evaluated the spatial and temporal distribution characteristics and evolution trends of the water resources. The main conclusions are as follows: ①The amount of water resources in southern China accounts for 81.5% of the national water resources, which is significantly higher than the 18.5% in northern China.② The evolution of China’s water resources is characterized by significant regional differences, with the total amount of water resources decreasing from southeast to northwest, while the water production coefficient in the south is generally higher than that in the north;③ From 1956 to 2016, the amount of water resources increased slightly in the northwest and southeast, but decreased in other regions;④ Evapotranspiration consumed 54% of the precipitation, followed by surface runoff and groundwater recharge.