Scale effect of population and area exposed to water scarcity based on different recurrence periods: A case study of Gansu Province, China

Abstract

Despite broad research on water scarcity from various perspectives, there is a lack of the spatiotemporal scale effect of water scarcity assessment. Here, based on multi-source data and mathematical models, we aim to assess water scarcity degree at different spatiotemporal scales in Gansu Province, China. The results indicate that Gansu Province had a moderate water scarcity, and the extent of water scarcity within the same recurrence period shows significant spatial differences. From 1960 to 2020, counties within the same city had a higher probability of facing the same degree of water scarcity, while counties in different cities had a relatively random probability of facing the same degree of water scarcity. There is a significant positive correlation between the year and the population or land area facing different extents of water scarcity. The proportion of the population and area facing water scarcity was generally smaller at the city-scale than at the county-scale during the same recurrence period. It can be concluded that the scale effect assessment is helpful to uncover the differences of water scarcity facing county, city and province, and thus conducive to accurate water resources planning and management.

Keywords

• Water scarcity
• Scale effect
• Recurrence period
• Spatial correlation
• Gansu Province