台灣南部地區水產養殖業水資源永續發展對策 - 綠色水產養殖池及水循環回收系統之研發 ,-台灣南部地區水產養殖業水資源永續發展對策 - 綠色水產養殖池及水循環回收系統之研發

Abstract

台灣地區養殖業主要集中於台中以南，養殖面積佔全台灣2/3 以上，一般水產 養殖業一公頃面積魚塭所需之淡水用量：鰻魚為33.2 - 55.3 萬噸、蝦類為11.4 - 17.2 萬噸及虱目魚為3.8 - 4.9 萬噸。截至2010 年11 月，南部地區水產養殖業淡水 用水量每年高達489 百萬噸，顯示養殖業對淡水之需求至為殷切。然而台灣南部因 降雨不均與河川污染嚴重，水資源長期匱乏，台灣80%雨量主要集中於6-7 月，一 年當中有十個月是乾旱期，且南部河川如二仁溪、東港溪與高屏溪等，污染至為嚴 重，供水品質不佳。淡水資源取得不易，漁民仰賴地下水為養殖池補注水源，超抽 地下水的結果，衍生出土壤液化、土壤鹽化、地層下陷與高鐵危機等危及國家發展 等重大問題，此一問題不僅應予以高度重視且急待解決。 水產養殖廢水含有高氨氮及病菌，排放於水體中易造成污染。過往大部份研究 僅針對處理養殖廢水與回收之效能做探討，對於處理前後之養殖水並無做生物活性 監測，故無法得知回收水是否會影響漁池生物之活性,以及可否回用。此外目前雖 已有少部分養殖場具有廢水處理系統，但是礙於系統施工與維護不易、操作介面困 難、初設成本高等缺點，造成漁民接受意願低，所以研發與建立簡易組裝與高效率 水處理系統搭配水質及生物活性自動監測系統應為養殖業永續經營一條可行的途 徑。 本計畫提出綠色水產養殖池及水循環回收系統之研發，研究內容包含三大項目: (1) 水產養殖池水生態循環處理系統之研發與功能測試，此系統具有可調式空間設 計、可快速組裝與更替植生植物並具有移動方便與養殖廢水特性; (2) 水產養殖池水 套裝式循環處理模組之研發與功能測試，具有快速組裝及可移動與高效能淨水之 功能; (3) 水產養殖池水水質及生物活性自動監測系統，以本土魚苗為監測對象，最 符合實際養殖水質情況，能快速檢測水中是否含有影響生物活性之污染物，具有高 靈敏性與精確性。此三大項目可幫助水產養殖業監控水質與養殖水之再生循環使 用，減少水資源濫用；套裝式循環系統於災害發生時，尚可做為緊急民生供水設 施。此研究案之成果，若全面推廣於養殖業，每年預計可產生8,700 萬噸之水資源 (總使用量之80%)，不但可補足水產養殖業用水之不足，如有餘裕，更可以補充地 下水，達到平衡地下水與確保養殖業永續經營之目標。

In Taiwan, two thirds of aquacultures are located in the south of Taichung, in which about 1/3 are fresh water fish farming. Although the amount of fresh water for each hectare of fish farm varies with fish species, the demand is significant. According to the Government report in Nov. of 2010, the annual fresh water consumption by aquaculture industry in southern Taiwan alone has reached 489,000,000 m3, indicating a great regional demand for fresh water by fish farming. However, the South has long suffered from water shortage mostly due to the uneven precipitation, with around 80% precipitation concentrated in June and July. In addition, most rivers in southern Taiwan are highly polluted. As a result, farmers turn to groundwater for water supplement, leading to the over-pumping of groundwater and the consequences of environmental impacts such as soil liquefaction, soil salinization, and land subsidence which jeopardizes the life of high speed rail. Conservation of groundwater has, therefore, become one of the top priorities in Government policies. Wastewater from aquaculture industry contains high-strength ammonia and pathogens, which should not be discharged into water body directly. Many studies have been conducted to investigate the feasibility of recirculating the aquaculture wastewater. To safeguard the production of fish farming as well as the health concern of the recycled water, the monitoring of biological activity of the treated water must be considered. On the other hand, fish farmers are not enthusiastic about the conventional wastewater treatment process, mostly due to the high capital cost, the hardship in construction and maintenance, and others. Therefore an efficient and user-friendly recirculating aquaculture system integrated with water quality and biological activity monitoring must be developed for sustainable aquaculture. The purpose of this study is to develop a green aquaculture pond and water reuse recirculating system. It is comprised of three projects: (1) development and verification of a water recirculating system by constructed wetland, (2) development of a packaged recirculating aquaculture system of speed-assembly and high mobility, and (3) development of an automated water quality and biological activity monitoring system of high sensitivity and precision. The integration of these three projects will effectively treat and reuse the wastewater to reduce the demand for fresh water resource. The packaged recirculating system can be easily transported to areas of water shortage due to natural disaster for water production. It is anticipated that the comprehensive promotion of this system will sufficiently supply the fresh water demand by aquaculture in southern Taiwan to sustain the fish farming.