Sustainability of groundwater and its effects on ecosystems

AASA Regional Workshop on “The Roles of Academies of Sciences in Water and Energy Problems in Central Asia and Ways for their Solutions, 30-June 2 July 2011, Bishkek, KirgizstanGroundwater’s global role as a vital source of fresh drinking water is well documented, and efforts are underway in many parts of the world to manage groundwater reserves responsibly and sustainably. A large percentage of the world’s population lives in cities and either depends on or is affected in some way by groundwater. This ever increasing demand on groundwater has led to overexploitation of the aquifers and degradation of groundwater quality particularly in the last 50 years. Available evidences indicate that regional changes in climate (i.e., increases in temperature and reduction in precipitation totals and patterns) have already affected groundwater resources and ecosystem in many parts of the world. In future, climate change is expected to intensify groundwater related problems due to reduced recharge rates and increased demand for domestic, agricultural and industrial water supply. Thus, the basic concern is the sustainable management of groundwater resources such that it is not depleted while the increasing demand is effectively satisfied. Based on these fundamentals, the purpose of this study is to present an overview of groundwater problem in different parts of the world and to present an overview of the current knowledge in the area of climate change impacts on water resources. Case studies from the Mediterranean Region, the Caspian Sea Region and the Aral Sea where safe water resources are typically scarce and became steadily scarcer are presented. In particular, access to high quality drinking water will become more of a problem than it currently is in these and in many other parts of the world. Decreasing precipitation and reduced recharge of groundwater resources are now considered to be one of the reasons for declining groundwater quality. Finally, these drastic changes in the hydrology of the groundwater system are also responsible for many changes in ecosystems where some are irreversible