本研究以新竹濱海野生動物區為例，透過文獻回顧與案例分析嘗試瞭解以牡蠣養殖作為濕地復育中自然復育之工具，並評估其所造就之非食用效益，換言之，透過牡蠣特性所累積之重金屬濃度可以淨化水質的效益，將有機會大於販賣之經濟產值。本研究透過文獻蒐集找出牡蠣對重金屬蓄積濃度以及運用牡蠣年產量計算，得到單一牡蠣對於水中銅離子與砷離子之重金屬累積速率常數分別為446~1,066(mg/day)與3.21~4.63(mg/day)，推測養殖一年的牡蠣體內銅累積量可高達512~1,201 (mg/kg)，砷的累積量則約為2.21~3.97(mg/kg)(吳春吉，2006)，經過初步計算，西元1995年新竹香山牡蠣年產量45噸應可吸附銅累積量約23,040~54,045(g) ，而砷累積量約為99.4~178.65(g)；西元2010年牡蠣養殖產量降至6噸，據此推測吸附銅累積量約為3,072~7,206(g)與砷累積量13.26~23.82(g)。新竹當地年產量變化逐年降低顯而易見，但所失去可能之重金屬吸附量較不易令人發現。
In recent years, wetland conservation appeal had not been interrupted in the world. Oyster farming areas are widely distributed and overlapped with coastal wetland in the western coastal of Taiwan. However, coastal development affected some oyster farming areas or national wetlands by river born polluted water with heavy metals. The oyster farming in the coastal of Hsinchu Siangshan is one of the important cases. The heavy metal pollution impacts the oyster farming in Hsinchu Siangshan that the cultured oyster is out of use. It's not only affecting the livelihood of local fishermen, but also the wetland ecosystem service. The strategy of Hsinchu City Government is prohibiting any oyster farming activity by establishing Hsinchu City Coastal Wildlife Refuge. However, the ecological balance of the environment at Hsinchu Siangshan wetland has been broken, the policy of the restoration achieve is worth exploring.
In the case of Hsinchu City Coastal Wildlife Refuge, this study suggested to use oysters as a tool of natural recovery by literature review and case studies. Assessment of the effectiveness of the natural recovery by oysters was also discussed. We suggested that it may have an opportunity to purify the polluted water by restrictive oyster farming, but not for selling as food at all. Through the literature review and case analysis, we found that the uptake rate constants estimated for copper and arsenic are about 446~1066(1/day) and 3.21~4.63(1/day), respectively. Based on the predicted uptake rate constants, the accumulative amounts of heavy metal in oyster cultured for one year could reach 512~1201 (mg/kg) of copper and 2.21~3.97 (mg/kg) of arsenic. Oyster production in Hsinchu Siangshan were 45 tons in 1995 but sharply decreased to 6 tons in 2010. After preliminary calculations, the accumulative amounts of copper and arsenic in oyster are about 23,040~54,045(g) and 99.4~178.65(g), respectively in 1995, but they could be 3,072~7,206(g) and 13.26~23.82(g) in 2010.
This study provided a framework for wetland restoration by oyster farming at Hsinchu Coastal Wildlife Refuge and providing a solution by searching literature and assessment of oyster farming. The government should invest about 11 million per year to purchase the imitatively farmed oyster. It could be the way to recover both the polluted wetland and faded oyster farming fisheries.