Abstract:
In order to study the spatial and temporal response and driving factors of groundwater depth to precipitation in the Yellow River Delta, based on the time series data of groundwater depth of 14 typical monitoring wells and precipitation of meteorological stations from 2006 to 2010, the Kendall's rank correlation, Cross-Wavelet and Wavelet Coherence methods are used to analyze the spatial and temporal response patterns of groundwater depth and precipitation. Based on the data of land use types, micro- geomorphic types and soil texture, the quantitative attribution of the relationship between precipitation and groundwater depth was also explored by using the geographical detectors method. The results show that (1) groundwater depth is negatively correlated with precipitation, and the spatial difference of their relationship is obvious. According to the effect of precipitation on groundwater depth, the relationship between groundwater depth and precipitation is divided into three spatial patterns in the study area: pattern 1 with
τau ranging between -0.45 and -0.30, pattern 2 with
τau between -0.30 and -0.15 and pattern 3 with
τau between -0.15 and -0.01. (2) From pattern 1 to pattern 3, the temporal lag of groundwater depth to precipitation is becoming shorter, which is 178.36, 146.43, 35.51 d, respectively. In all patterns, the change of groundwater depth is very sensitive to heavy precipitation. (3) Land use types, soil texture and micro-geomorphic types have significant effects on the relationship between groundwater depth and precipitation. The contribution rates of interpretation are micro-geomorphic types (0.280 7) > land use types (0.244 1) > soil texture (0.163 8). There are synergistic enhancement effects among the driving factors. The synergistic enhancement effect of land use types and micro-geomorphic types is the greatest, which is 0.749 0. Different spatial and temporal patterns of groundwater depth and precipitation in the Yellow River Delta are revealed and a quantitative attribution is also made to them, which provides a scientific basis for the study of water cycle process, groundwater resource management and ecological protection in the Yellow River Delta.