This paper is the result of the hydrogeological survey engineering.

Objective The problems of drought and water shortage in the karst areas of southern China are extremely prominent, the storage and distribution of karst groundwater are complex, and the utilization rate of development is low, based on years of investigation and research work, the characteristics of groundwater resources in the karst area in southern China are systematically summarized, and the countermeasures for water resources protection are studied.

Methods Based on the characteristics of groundwater resources, the types of groundwater systems, the spatial structure of groundwater systems, and the uneven distribution of time and space in the southern karst area, the countermeasures for water resources protection in the southern karst area are proposed.

Results The southern karst area can give full play to the role of groundwater resource security from the following three aspects: One is to grasp the law of groundwater storage and distribution, and play the role of decentralized water supply and emergency water supply. The second is to strengthen the construction of storage projects to solve the problem of unevenly distributed water resources. The third is to establish a sustainable use model of groundwater resources combined with ecological reconstruction and economic development.

Conclusions The groundwater storage conditions in the southern karst area are complex, and there are many types of karst water systems in the surface zone, karst underground rivers and pipeline flow systems, karst large spring systems and scattered discharge groundwater systems, with different scales and different development and utilization. It has superposition in the vertical upward, and the time-space distribution of karst groundwater is seriously uneven; The potential for development and utilization is large. Under the guidance of the earth science system theory, it is necessary to find out the law of the allocation and distribution of karst water resources, scientifically evaluate the amount of groundwater resources, and formulate water resources development, utilization and protection plans according to local conditions, to provide technical support for poverty alleviation, ecological civilization construction and rural revitalization.