Variations of karst water and environmental problems in North China

Along with the changes of natural surroundings and the intensified human activities, great changes have taken place in input, output, and structure as well as transform relation in karst groundwater system of Northern China. In a few decades, 30 % of karst spring dried up, 80 % of spring flux dramatically degraded and regional karst groundwater level is continuously declining at the speed of 1 to 2 m/a. At the same time, the water quality in more than 20 % of main karst water discharge zones get below Class III and the overall trend is worsening. In addition, karst water environment problems, such as karst collapses, ground fissures, seawater intrusion, lowering in tourism function and lost of ecological function exists, are intensifying the shortage of water resources. According to investigation and data sorting of typical cases, this article summarizes problems of hydrogeologic environment and its development trend in Northern China karst area to attract attentions of all sectors of society to promote the protection of karst groundwater. Meanwhile, the article provides reference for further research.