Susceptibility zoning and control measures on land subsidence caused by groundwater exploitation

Excessive artificial extraction of groundwater has caused the continuous decline of groundwater levels and,as a result,triggered a large area of land subsidence.To avoid a wider range of land subsidence,the authors used the clay layer thickness,the drawdown rate of groundwater level and groundwater exploitation as three impact factors to carry out studies.In accordance with their respective extent of impact,the impact factor weights were determined,the overlay method in GIS was used to divide land subsidence into susceptibility zoning.In combination with water resource allocation of South-to-North water transfer,this paper has proposed the control measures on land subsidence,thus providing a scientific basis for layout optimization of groundwater exploitation and land subsidence.