Sustainability of Groundwater Resources in the North China Plain

Abstract

The Worldwide Hydrogeological Mapping and Assessment Programme (WHYMAP) was launched in 2002 by UNESCO as the lead agency within its International Hydrological Programme (IHP) and the UNESCO/IUGS International Geoscience Programme (IGCP), the Commission for the Geological Map of the World (CGMW), the International Association of Hydrogeologists (IAH), the International Atomic Energy Agency (IAEA) and the German Federal Institute for Geosciences and Natural Resources (BGR). WHYMAP aims at collecting, collating and visualising hydrogeological information at a global scale, to convey groundwater-related information in an appropriate way for global discussion on water issues and to give recognition to the invisible underground water resources within the UNESCO Programme on World Heritage. WHYMAP also brings together the huge efforts in hydrogeological mapping at regional, national and continental levels. Thus BGR, together with its partners, is gradually building up a geo-information system (WHYMAP-GIS) in which the groundwater data are managed and visualised. The WHYMAP steering committee cooperates closely with the International Groundwater Resources Assessment Centre (IGRAC) and the Global Runoff Data Centre (GRDC). Other regional centres, scientific organisations, universities and freelance experts in hydrogeology may also participate in the future. WHYMAP has produced two special editions of the global map at the scale of 1:50,000,000, i.e. one for the International Geological Congress and the CGMW meeting at Florence, Italy, August 2004, and a second focussing on Transboundary Aquifer Systems, issued for the 4th World Water Forum in Mexico City in March 2006. The latest is a 1:25,000,000 wall map of the Groundwater Resources of the World. It shows various characteristic groundwater environments in their areal extent: blue colour is used for large and rather uniform groundwater basins, green colour areas have complex hydrogeological structure, and brown colour symbolises regions with limited groundwater resources in local and shallow aquifers. In addition the groundwater recharge rates are shown by colour shades. Areas of heavy groundwater abstraction prone to over-exploitation and areas of groundwater mining are mapped, where known. Groundwater quality is an important issue and areas of high groundwater salinity are highlighted. The global Groundwater Resources Map contains only selected information on groundwater. For reasons of clarity and readability, important complementary information has been deferred to a set of four insert maps at 1:120,000,000. These thematic maps show “mean annual precipitation”, “river basins and mean annual river discharge”, “population density” and “groundwater recharge per capita”. Comparison between the main Groundwater Resources Map and these thematic maps should help understanding of the global picture of groundwater and surface water resources and provide insights into their pressures, in particular the priority use for drinking purposes. WHYMAP-GIS is updated regularly and map makers and hydrogeologists are invited to contribute to the programme.