Karst development and utilization: serious water shortage and floods on the surface of karst area have considerable impact on agricultural production. However, there is abundant groundwater: runoff coefficient is 50-80% in tropical karst area, 30-40% in subtropical karst area, and 10-20% in temperate zone. In some limestone areas in North China, groundwater flows as springs in the front of mountains, such as the spring of Yuquan Mountain in Beijing, Baiquan Spring in Hui County, Henan, Jinci Spring in Taiyuan, Shanxi, Niangziguan Spring in Pingding County, Shanxi, and Baotu Spring in Jinan, etc. Rational development and utilization of karst springs is of great significance to the development of industry and agriculture. There are many underground rivers in the south, and methods like introducing karst springs to block underground rivers and drilling water wells can solve the issue of industrial and agricultural water use. Underground rivers have stepped vertical section with abundant water energy resource, which can be used for damming and electricity generation. For example, Liulangdong Hydropower Station in Qiubei, Yunnan, is the first hydropower station in China that uses underground rivers. Hunan and Chongqing have also built many over-400-kW underground hydropower stations using this superior condition. Underground caves in karst area often cause reservoir leakage, which is an unstable factor for dam, traffic lines, and factory buildings. Studying and detecting the distribution of underground caves and taking measures timely are the key to successful construction in karst areas. Karst area is rich in deposits such as limestone, dolomite, marble, gypsum and rock salt, etc. There are Bauxite deposits on karst erosion surface and in depression; lead, zinc, sulfide, mercury and other quartz sand deposits accumulate in ancient caves and fissures; underground caves are also good places for oil and natural gas, and some oil fields in North China are located in karst area. Some caves can be used as underground factories and warehouses.