Research on evaluation and early warning of groundwater resources carrying capacity in Hebei Province

A series of ecological and environmental problems occur in Hebei Province due to the continuous over-exploitation of groundwater. The reasons for these are that human activity intensity is beyond the groundwater resources carrying capacity and there is lack of timely and effective early warning method. The aims of this study is to build the groundwater resources carrying capacity evaluation system conforming to the reality of Hebei Province, improve previous warning methods that need to set the fixed warning interval value of groundwater levels and water volume and address some problems caused by the regional differences of groundwater level, such as macroscopic evaluation difficulty, huge workload and being unable to correct dynamically. Based on resource attributes and social attributes of the groundwater resources, this paper uses the comprehensive analysis and judgement method of index system and builds the carrying capacity evaluation system on two levels: carrying background and carrying status. The “dual-control linkage” warning system is used, which mainly focuses on the degree of groundwater development and utilization and modifies the extent of groundwater level changes, to achieve dynamical linkage of the two indexes without setting the fixed interval value of groundwater level and water volume. The research results show that the overall carrying background of groundwater resources in Hebei Province is good. Because the degree of groundwater development and utilization is high, the carrying status of groundwater is mostly in the over-load state.The results show that the bearing capacity of the central and southern parts of the Taihang Mountains is higher than that of the northern part, Yanshan mountain area and the Bashang region, and the bearing capacity of the piedmont alluvial plain is better than those of the central lacustrine plain and coastal plain. Influenced by the salt water distribution, the huge water consumption in industrial and agricultural production and other factors, red and orange warning areas of groundwater are mainly distributed in the Cangzhou and Hengshui areas of the central alluvial lake plain of the Hebei plain, Hanxing junction area of the Taihang piedmont plain and urban peripheries. Evaluation and warning results conform to the reality of Hebei Province and the system has the advantages of strong regional applicability, good operability and easy access to data.