Groundwater Dynamic Combination Model

On the base of analyzing the statistics of dynamic state ofgroundwater level and using kinds of maths methods, the theme separatedgroundwater level into tendency function,periodic function and stochasticcomponents and synthetic maths model is set up. To tendency function,it'sexpressed by linear synthesis of inferior functions with the method of timeregression. To periodic component, main period is separated on theprinciple of Fisher. To stochastic component, autoregressive-movingaverage model is set up by the method of founding system model. It'sparameters' precise estimates are decided by nonlinear minimum squarelaw. It's module is decided by F principle. To predict groundwaterlevel,the method of prolonging time is used on trend component .And tostochastic component, it's Green function is get and the minimum varianeis used. The model tested by true example get a ideal result. At the sametime,programs are designed for the synthetic maths model,which bringthis method great popularize value and do some contribution for theinformation of environment geological supervision.