2006-05-042024-05-14https://scholars.lib.ntu.edu.tw/handle/123456789/661002摘要：臺灣沿海地區由於長期性地超抽地下水，造成地下水位下降、地層下陷與海水入侵至地下含水層之現象，導致該地區土壤遭受鹽化污染，影響農地利用，至今仍未終止，上述情形尤以雲林縣沿海地區與屏東平原最為嚴重。由此可知，本問題相當值得重視，亦具有其研究之必要性。增加地下水補注量為改善海水入侵與農地鹽化現況重要方法之一，因此本計畫擬建立數學模式，藉以分析田間地下水補注量對改善沿海地區土地鹽化之影響。本計畫結合PMWIN之MODFLOW地下水流模式及MT3D溶質傳輸模式，配合民國87年至89年雲林地區地下水位及水質資料，以數值模擬方法來建立此區域地下水鹽化模式。研究結果顯示其地下水流及水質模擬與現地觀測相當吻合，本研究之地下水鹽化模式符合現地情況。以氯離子濃度為鹽化指標分析顯示沿海地區水質鹽化程度嚴重，經設計地下水補注量案例以補注15年後之口湖及麥寮兩鄉鎮氯離子濃度下降最多，與民國89年相比較減少33%，沿海地區整體平均氯離子濃度則降低30%。<br> Abstract: The problem of soli salinity hazard in Yunlin area has been recognized and widely drawn special attentions in Taiwan. Field groundwater recharge is a well-known method for controlling saline water intrusion. It is important to quantify the effects of the proposed mitigation measures for controlling saline water intrusion in Yunlin area. In this project, PMWIN (Processing MODFLOW for Windows) is selected to establish the groundwater flow model of the Yunlin area. Then the chloride concentration throughout Yunlin area is simulated using a solute transport model called MT3D. Based on field groundwater recharge, mitigation measures of the soil salinity hazards are designed and simulated. The simulated results show that field groundwater recharge is a very effective method for controlling saline water intrusion. As compared to 1990, the proposed mitigation measures yield an average chloride concentration reduction of 30% in the coastal area in 2005.地下水補注海水入侵土壤鹽化groundwater rechargesaline water intrusionsoil salinity