2019-01-042024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/677989摘要：底泥為重金屬與難降解有機污染物之環境累積終點。即使河川水質獲得改善，底泥中污染物濃度不再增加，原先累積於底泥的污染物仍可能再度釋出回到水體，造成潛在的生態風險。依環保署近年河川環境調查計畫成果顯示，國內重要河川底泥中含有不同污染程度的重金屬及有機物污染，有些污染物甚致超過其底泥品質管制標準上限。當底泥污染物濃度超出標準時，應啟動適當之風險評估。目前國內對於底泥重金屬之生態風險評估較缺乏系統性研究，因此需要確立本土之底泥生態風險評估指標及參數、建置更完整的生態風險評估流程，以協助底泥生態風險評估系統的運作。 本專案計畫以老街溪底泥重金屬污染為例，探討以下研究目標：(1)分析老街溪流域底泥重金屬的濃度及分佈; (2)利用不同的污染指數(pollution indices)，量化底泥中個別及整體重金屬的污染程度; (3)評估底泥重金屬的生物效應及潛在的生態風險; 及(4)利用多變量統計方法(multivariate statistical methods)，分析重金屬污染的可能來源。 本專案計畫希冀所建置之底泥生態風險評估架構，未來應用於臺灣其它主要河川底泥污染物的生態風險評估。此外，透過建置符合臺灣本土需求之生態風險評估參數及流程，本研究將協助完善底泥生態風險評估作業，並且為主管機關提供生態環境管理之依據。 <br> Abstract: Sediment is the ultimate sink in the environment for heavy metals and persistent organic pollutants in the environment. Even the water quality has been improved or the amounts of pollutants are not continuously increased, these contaminants could be re-released into the aquatic environment from the sediment, thereby posing potential ecological risk. Recent EPA reports have shown that sediments from several major rivers in Taiwan have been polluted by heavy metals and some organic compounds. Some of these contaminants exceed the upper limits of sediment quality guideline, suggesting that sediment ecological risk assessment should be conducted. However, current ecological risk assessment framework in Taiwan requires systematic approach by establishing appropriate parameters, as well as developing integrated ecological risk assessment procedure. Therefore, this project uses sediment heavy metal pollution in Laojie river as a case study to fulfill following research aims: (1) to analyze concentrations and distribution of heavy metals in the sediments of Laojie river; (2) to quality degree of pollution posed by individual and overall heavy metals by using different pollution indices, (3) to assess ecological risk posed by heavy metal contamination in the sediments, and (4) to determine source of the pollution by using multivariate statistical methods. The ecological risk assessment framework conducted in this project is expected to be utilized by future studies assessing sediment ecological risk in other Taiwan rivers. In addition, by defining appropriate parameters and risk assessment procedure, this study can contribute to current ecological risk management as well as policy making.生態風險評估底泥重金屬老街溪ecological risk assessmentsedimentheavy metalsLuoge river