Study on the dynamic characteristics of shallow groundwater level under the influence of climate change and human activities in Cangzhou, China

Abstract

Abstract Based on the monitoring data of groundwater level, mining data and meteorological data from 1986 to 2015 in Cangzhou City, the change characteristics of depth of groundwater level were studied. On this basis, the nonparametric statistical test method (Mann–Kendall method) was used to study the trend of depth of groundwater level. Besides In addition, the principal component analysis method and grey correlation method were used to study groundwater influence factors. Finally, the multivariable time series model was used to predict the depth of groundwater level. The results showed that in the past 30 years, influenced by human activities and meteorological changes, the groundwater flow field in 1986–2015 was generally move from southwest to northeast, the depth of groundwater level was increasing from the initial 3.26 to 4.06 m, with an annual increase rate of 0.027 m/a; the contribution rate of exploitation factor, precipitation factor, evaporation factor were 40, 20 and 40%; the fitting figure of the observed values and the predicted values were very good, with an average relative error of 7.73%. According to the prediction schemes, when the evaporation increases by 5%, and the agricultural exploitation decreases by 5%, the depth of groundwater will reach 3.39 m; when the evaporation increases by 10%, and the agricultural exploitation decreases by 10%, the depth of groundwater will reach 3.32 m. This study had important reference significance for regional groundwater treatment and rational utilization.