屏東平原地下水蘊藏量極為豐富，多年以來大量地下水供應於民生、農業及養殖用水，但由於缺乏地下水資源永續利用的概念，導致本地區超抽地下水，進而造成地層下陷和海水入侵及地下水鹽化問題日益嚴重，因此管理及保育地下水資源已成為該地區很相當重要的課題。本研究目的是整合地下水水質與水位變化條件，當屏東平原有足夠地表水源時，針對飲用、養殖及灌溉等用水標的之地下水優先停止抽用的區域規劃。首先水質部分利用多變量指標克利金法分析飲用水、養殖及灌溉用水水質空間變異，並以機率劃定適合與不適合飲用、養殖及灌溉之地區；地下水位變化部分以模組化地下水流模式PROCESSING MODFLOW（PMWIN）進行屏東平原地下水流動及補注水量的模擬，配合均方根誤差（RMSE）率定模式，以求出符合現地水文地質架構之模型。接著使用水權核發量作為模式補注量，模擬含水層補注地下水位變化，模式補注時間為半年，以回注水權方式當作停止抽用地下水，將地下水位排序結果結合水質空間變異排序結果，用以檢核地表水管理規劃之可行性。結果顯示南州為養殖用水量與水質條件為全區域較差，故排序最前，接著依序為新埤、佳冬、潮州、枋寮等地。再來灌溉用水量與水質條件全區域較差地區為枋寮，然後依序為佳冬、新埤、萬巒、南州等地。最後是飲用水量與水質條件全區域較差地區為新埤，依序為潮州、萬巒、大樹、長治，以上鄉鎮區建議依照使用目的以地表水代替地下水使用，以減輕對含水層的負擔。 ;The groundwater is very rich in the Pingtung plain and a main water supply source for drinking, irrigation and aquaculture demands. However, because the concept of sustainable use of groundwater resources is weak, excessive pumping of groundwater is common in this area, resulting in the occurrence of increasingly serious the problems in land subsidence and sea water intrusion. Therefore, management and conservation of groundwater resources in the Pingtung plain have become a very important issue. This study aims to conjunct use of groundwater and surface water in the Pingtung plain based on water quality and quantity, and assess the locations of the suitable decreasing groundwater extraction. The study results could establish a management and development plan of low-impact groundwater resources for the multi-purposes, and prevent decreasing groundwater tables and the occurrence of the land subsidence and sea water intrusion in the Pingtung plain. This study carried out the simulation of groundwater flow using MODFLOW in the Pingtung plain after model. After model calibration, the developed groundwater flow model can be used to predict the variation of groundwater flow for specified situations. The research findings can provide a plan reference of regional water resources supplies for government administrators and reach the sustainability of water resources development.
