海潮及受其影响的海岸带地下水位具有复杂的周期性变化和趋势性变化。本文建立趋势项与周期项之和的数学模型来描述水位的实际变化。用线性函数拟合其趋势项,用傅立叶级数拟合其周期项,用频谱分析和最小二乘法确定周期项函数。用实测水位和计算水位的误差平方和检验拟合结果,

Fitting and prediction of the changes in tide and

groundwater levels in coastal aquifers

Zhou Xun1, Ruan Chuanxia1,2, Fang Bin1, Ou Yecheng3,

(1. School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China;

2. Institute of Tianjin Geothermal Investigation Development and Design, Tianjin 300250, China; 3. Beihai Institute of Hydrogeology, Engineering Geology and Mineral Resources in Guangxi, Beihai,

Guangxi 536000, China) Abstract

Complex periodic changes and trending changes can be observed in tide and groundwater levels affected by the tide in coastal aquifers. In this paper, mathematic models including a trending term and a periodic term are developed to describe the changes in the water levels. The trending term can be described by using a linear function, and the periodic term, by a Fourier series. The spectrum analysis method and the minimum square method are used to construct the Fourier series. Fitting is verified with the sum of the square of the abstraction of the observed and computed water levels until satisfactory fitting is obtained. The developed mathematical models can be employed to predict the changes in the tide and groundwater levels in coastal aquifers. The predictive water levels are thought to reflect the characteristics of the observed time series of the tide and groundwater levels near the coastal. The models are suitable in short-time prediction of water levels in the coastal aquifer.

Keywords: Coastal aquifer; spectrum analysis; fitting; prediction

第一作者简介：周训，男，博士，教授，博士生导师，1963年出生，现在中国地质大学（北京）水资源与环境学院从事水文地质、环境地质的教学和科研工作。zhouxun@。