多物種傳輸解析解模式對於了解地下環境中污染物之傳輸行為是一種有效工具。前人所提出的多物種傳輸解析解模式多使用直鏈衰變的假設,此反應途徑的假設不符合污染物實際的衰變情況。然而從過去文獻可以發現,不同鏈衰變反應途徑對於溶質傳輸有很大的影響。本研究目的為發展考慮不同鏈衰變反應途徑的多物種傳輸解析解模式。研究中利用Laplace轉換與廣義型積分轉換以及一系列逆轉換來求得耦合移流-延散方程式的解,並撰寫成FORTRAN程式執行解析解模式的計算。所得解析解再利用數值解之Laplace有限差分法來進行相互驗證,結果顯示非常吻合,證明解析解的正確性與FORTRAN計算程式的準確性。最後將發展的解析解模式應用在實際污染物238U衰變與TCE降解的反應途徑上。;Multispecies transport analytical model is a cost-effective tool for better understanding the transport behavior in the subsurface environment. Analytical solutions for coupled multispecies solute transport problems are difficult to derive and relatively few. Although several multispecies transport analytical model have already been reported in the literature, those currently available have the primarily been derived based on advection-dispersion equations with straight chain decay reaction pathways. This study presents some new analytical model for multispecies transport with different chain decay reaction pathways. The closed-form analytical solutions to a set of coupled advection-dispersion equations are obtained by using the Laplace and generalized integral transform. Solutions for different chain decay reaction pathways are generated and are verified against numerical model that solved the same governing equation systems using the Laplace transform finite difference technique.