微量金屬是所有生態系統中，尤其是水中生物地球化學反應的主控要角。許多微量金屬更是生命中不能缺少的營養要素，在濃度極低或利用率不夠時，生物會出現營養不足狀況，發育不良。另一方面，許多營養金屬在高濃度時卻會造成有害（例如Cr，Cu，Ni，Se，Zn）或甚至劇毒（例如As，Cd，Pb，Hg）致命反應。人為活動，如採礦、化石燃料燃燒或工業製程，改變了許多微量金屬的生物地球化學循環，急速增加其在環境中的濃度及可用性。本課程的目的是講解有關微量金屬環境化學的重要科學背景；描述各種水環境中的微量金屬循環，特別著眼於河口環境；各種地球化學反應塑造的過程，人類如何影響以及如何受到影響；探討各個環境之間的聯結，並說明生物地球化學過程與微量金屬之間的耦合反應；最後闡述現今微量金屬的生物地球化學研究的一些突破發現與發展。
Trace metals are imperative in the biogeochemistry of aquatic ecosystems. Many trace metals are essential micronutrients for life, organisms will show nutrient deficiencies at very low concentrations or availability. Many metals can have deleterious effects at high concentrations (e.g. Cr, Cu, Ni, Se, Zn) or even toxic ((e.g. As, Cd, Pb, Hg). Anthropogenic activities, such as mining, fossil fuel combustion or industrial processes, have greatly altered the biogeochemical cycles of many trace metals and increased their availability. The objectives of this course are to provide crucial background information on the environmental chemistry of trace metals; describe trace metal cycling in various aquatic environment, special emphasis will be on estuarine environments; the processes that shape them, how humans affect them and are affected by them; Focus on linkages between these environments to illustrate coupling between biogeochemical processes and trace metals; at last, to provide some recommendations for future research on the biogeochemistry of trace metals.