Dynamic Features of Groundwater Level in Northern Qinling and Its Influence Factors

Groundwater is the main water supply source in the north of Qinling mountains. It is of great significance to study the dynamic variation of groundwater level and its influencing factors for rational development of groundwater resources and protect the ecological environment. This paper chooses the Huxian plain as the regions in the north of Qinling mountains, According to the groundwater depth, meteorological and hydrological data, combined with the hydrogeological conditions in the study area, using the Kriging method and principal component projection-clustering coupling model statistical, the temporal and spatial variation process of groundwater level from 1980 to 2019 was studied, the groundwater dynamic types were classified according to the main factors affecting groundwater dynamics, and the dynamic variation characteristics of groundwater level were analyzed. The results show that the groundwater level fluctuates and declines from 1980 to 2019. The interannual variation of alluvial plain and diluvial plain is large while the leading edge of alluvial fan is relatively small. The groundwater dynamic types in the study area can be divided into four types:hydrologic, precipitation-exploration, runoff, and precipitation-hydrologic-exploration type. Rainfall, river runoff and exploitation are the main external influencing factors of groundwater level change in the study area.