Research on the differences of karst hydrological systems between north and south China in a changing environment

摘要

The calcium-rich and discontinuous lithosphere has a very close relationship with the atmosphere, hydrosphere, and biosphere in Chinese karst regions, resulting in the appearance of a multi-level surface-underground double layer structure, where water, soil, rock and life are as one, producing a series of special environmental geological problems, such as soil erosion, drought, desertification, water depletion, land subsidence and collapse, mine flooding, etc. For example, a series of karst hydrological and ecological problems, caused by basic geological structure of karst areas in north China (Shanxi karst plateau) where coal is in the upper layer, and water is in the lower layer, coal and water are together and in one of the karst regions in south China (Yunnan-Guizhou karst Plateau) the soil is in the upper layer, and water is in the lower layer. Soil and water are separate and will be an important part of Chinese karst hydrology in the 21st century. This paper focuses on discussing the differences in karst area and water resources characteristics of karst hydrological systems between north and south China: (a) in south China karst regions, karst water supply capacity is large and dynamic changes are dramatic. In particular, in the mountain regions, water leaks rapidly into the underground so that a considerable part of karst water resources can not be used. Developing vegetation, constructing reservoirs in appropriate places, blocking the main channel of groundwater flow, and controlling karst caves, are used to improve the utilization rate of karst water resources, (b) in karst regions of north China, in the exposing, semi-exposing and karst water recharging regions, increase vegetation cover area and construct reservoirs to reduce evaporation and increase recharge; in coverage and karst water supply regions, lower mud and sediment yield of river to effectively control the balance of aquatic species; in burial regions, focus on considering the relationship between karst water and overlying other types of water resources.