潮汐作用对莱州湾南岸冬季地下水位的影响研究

摘要

Tidal fluctuation has a stable periodicity.When the groundwater is influenced by tide,this perio-dicity will be reflected on the variations of groundwater level.However,in practical cases,it is very diffi-cult to recognize the weak periodicity of groundwater level caused by tidal influence in the coastal regions since it is usually influenced by groundwater exploitation,rainfall and other factors.In this study,the groundwater level was processed by different methods,and the self-correlation analysis was used for verifi-cation.The results showed that after the removal of the long-term trends and the filtering process,the data periodicity characteristics of groundwater levels were mostly consistent with the tidal fluctuation.This demonstrated that the information regarding the tidal influence on the groundwater level could be effective-ly extracted through this method.%潮汐波动具有稳定的周期性,当地下水受其影响时,这种周期性在地下水位变化中必会有所反映,但同时也会受到人为开采地下水、降雨等因素的影响而很难被识别出来.通过谱分析认为莱州湾南岸地下水位同潮位共同存在12和24 h两个主要周期,采用傅立叶变化与去趋势分析结合的方法提取出了地下水位中受潮汐影响的频率成分,并利用自相关分析的方法对处理后的地下水位数据与潮位数据进行了对比分析.结果显示,虽然莱州湾南岸地下水受人为开采地下水影响显著,但通过去除长期趋势和提取频率的方法可以有效提取冬季地下水位中受潮汐作用影响的因素,从而为其他研究提供了一种有效的原始数据处理方法.