Editorial: Groundwater systems worldwide
Frédéric Frappart, Venkatesh Merwade
Abstract
Groundwater, with a total volume of 23.4 10 6 km 3 , represents 30% of the world's freshwater or 2.5% of the total global water storage. Thus, it is an important area of research and a valuable resource for humankind Groundwater is an essential component of the global hydrological and biogeochemical cycles and plays a major role in ecosystems sustainability Similarly, groundwater is an essential water resource for meeting various human needs, including domestic water supply, irrigation and industrial operations. Groundwater is often the last freshwater resource available for domestic use and irrigation once surface waters are depleted, especially in semi-arid areas and densely populated countries In many regions of the world, aquifers are the largest and safest drinking water supply