降雨下土壤入滲效應對地下水水位變化

A Study of Infiltration Rate of Soils as Related to Groundwater Level Fluctuations in a Period of Rainfall

張健財

《萬能學報》 36期 (2014/07) Pp. 217-223

摘要

本研究旨在探討降雨下，土壤入滲效應對地下水水位變化的影響模式。分為二階段進行，第一階段為探討針對降雨下土壤入滲效應對地下水位的變化效應，此土壤入滲效應，以維納濾波法，探討所需係數長度；第二階段利用Kalman filter所需之狀態變數，將採用第一階段所求得之維納係數最佳長度，作為有效模擬降雨量對地下水位變化之影響。本研究第一階段中欲探討降雨下土壤入滲效應之效應，將分別考慮從原始雨量中扣除1～2mm與黃金比例之值下，求得最佳維納係數長度和有效模擬地下水位受逕流量之影響。研究中取2009 NaBa水井之地下水位與雨量資料，應用迴旋運算模擬降雨形成的地表雨水對地下水位變化的響應，經測試多種不同的降雨量扣除值後，發現其中NaBa採用針對7小時之連續降雨量在土壤入滲效應扣除黃金比例，密合比例值較多。目前僅NaBa分析站資料，仍需分析更多站的水位及雨量資料來佐證上述之結果。對於處理長時間的水位變數紀錄中的降雨效應將利用Kalman filter。因此本研究將持續測試其他測站之降雨量與地下水位變化，選取多種不同維納係數長度，並考慮扣除土壤入滲效應之黃金比例值，擷取較可靠的響應係數長度，作為下一階段利用Kalman filter以動態模擬方式模擬地下水位受降雨之影響依據。

關鍵字

土壤入滲效應 ； 地下水水位變化 ； 迴旋運算 ； 降雨響應 ； 卡爾曼濾波

並列摘要

This project aims to investigate the relationships between groundwater level fluctuations and rainfalls. There are two stages, first the infiltration rate will eliminate and proceed with convolution by ground water level by Wiener Filter Method. The second stage, the Kalman's method will adopted to simulate the time dependent variation of the groundwater level fluctuations with respect to rainfalls based on the coefficients of Wiener Filter those were obtained at first stage analysis. The golden ratio number was adapted to the elimination the direct run-off of the rainfalls for the optimization of coefficients of Wiener Filter of the ground water fluctuations in this project. The results show that the coefficients contained 7 terms (hours) in the Wiener Filter is given the much matches with the trend of the ground water level fluctuation in the period of rainfalls at well of NaBa. More works would be done in the next stage of this research, for the base parameters of the analysis of Kalman filter state variables in the simulation of ground water level fluctuations due to the rainfall responses.

並列關鍵字

Groundwater level fluctuation ； Convolution modeling ； Rainfall response ； Kalman filter

參考文獻

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