Researchon the Causality between Geological Environment Degenerating and Groundwater Sustainable Exploitation in the Yellow River Downriver Plain

Since the end of 1950s, the geological environment is degenerating continuously, caused a series of geological environment problems, such as land subsidence, ground fissure, seawater or salty-water encroachment, and downward movement of saline-fresh water interface. All these problems were caused by the exceeded exploitation of groundwater during lately 60 years.At the 21 century, the quantity of groundwater exploitation is fleetly increased from 20×10⁸m³/a to 52×10⁸m³/a, which exceeds the available amount of groundwater 42×10⁸m³/a in the Yellow River Downriver Plain. Because of long time extra-exploitation and irrational exploiting distribution, the groundwater table kept descending, the cone of groundwater depression kept spread. Thus, theenvironment accidents are frequent appeared, the quality of geological environment is deteriorating. In order to preventthe further deteriorating of geological environment, the groundwater must be reasonably developed in the present condition, and the groundwater system in plain area must be rehabilitated and conserved.