Subsystem-level groundwater footprint assessment in North China Plain – The world's largest groundwater depression cone

Abstract

© 2020 Elsevier Ltd Groundwater is one of the most critical elements of global water resources. However, growing water consumption has resulted in rapid depletion of groundwater, which threaten the sustainable development of economy and environment worldwide. Groundwater footprint (GF) is the area of region capable of achieving the sustainable use of groundwater and healthy ecosystem simultaneously. However, existing studies for GF assessment fail to distinguish the difference between sub-systems at spatial and temporal scales. Moreover, the big error (>40%) always existed due to the coarse spatial resolution. Thus, the North China Plain (NCP), the world's largest groundwater depression cone, was selected as the first demonstration to perform GF assessment at subsystem level. Disparate groundwater subsystems in NCP show notable differences in terms of unsustainable levels. The NCP's average shallow and deep GF is 90.93 and 65.12 million km2 with the groundwater utilization intensity is 6.56. The variation of groundwater utilization intensity under different scenarios were analyzed. Combining all agricultural management could reduce groundwater utilization intensity by around 74.58% to 96.95%, resulting that groundwater could recover to the original health level nearly. It suggested that government should implement strict and holistic management policies to better access exploit and utilize groundwater, such as exploring alternative sources and adjusting the water use structure to achieve sustainable management of groundwater.