Assessment of water resource carrying capacity in karst area of Southwest China

Water resources are essential for sustainable economic and social development, especially in the karst regions of Southwest China. Guizhou Province was selected as a representative area to explore water resource carrying capacity (WRCC) in karst regions. The concepts of carrying capacity of utilization amount of water resource (CCUWR) and gross amount of water resources (CCGWR) were proposed to evaluate the scales of population, agriculture and economy that local water resources can support. Results show that actual values of population and cultivated land were much larger than the CCUWR, indicating that both population and agriculture were overburdened from 1999 to 2012. However, actual values of GDP were smaller than those of CCGWR and CCUWR, suggesting that water resources were in surplus relative to economic development. In comparison between actual values and those of CCGWR, the WRCC potential for the scales of population and cultivated land is low, but the potential for the economy is high. The discrepancy between the water resources and cultivated land was most pronounced in Guizhou. This paper indicates that it is urgent to enforce rational policies to ensure utilization efficiency of water resources in karst regions.