微囊藻毒是優養化湖泊水庫中經常被發現之有毒污染物，目前對微囊藻毒在水體中傳輸行為並不清楚，因此本研究主要目的為探討微囊藻毒傳輸影響因子，以釐清影響微囊藻毒於水體中的宿命。 自然水體中微囊藻毒以分佈作用吸持於底泥有機質，其等溫吸附線呈線性；對於表面均帶負電的微囊藻毒與底泥，彼此間的排斥力會隨 pH值改變而影響吸附量，結果顯示，微囊藻毒在水體中吸附量主要受到有機質含量、系統 pH 值影響，而底泥比表面積、平均孔徑及質地對於微囊藻毒之吸附量影響不大。 於水相環境中，水中的懸浮微粒和腐植酸溶液對微囊藻毒之傳輸具有影響，微囊藻毒可藉由吸持作用形成帶毒性之膠體並散佈於整個水體中；且水中懸浮微粒及腐植酸溶液對微囊藻毒光降解具有些許影響，當環境中存在懸浮微粒時會減緩微囊藻毒光降解速率，而腐植酸溶液會加速其降解，但此兩項因子並非像光照之光波長影響微囊藻毒之降解速率來的顯著，在UV-C照射下1小時內即可將濃度為1.6μg/mL之微囊藻毒降解完畢，而在UV-B照射下其至少需要5天時間。本研究經一連串的實驗並透過 HPLC/UV分析技術，得知底泥、懸浮微粒及腐植酸溶液之吸附與光降解對微囊藻毒於自然水體中之宿命具有影響。 Microcystin is a common toxin in the eutrophic lakes and reservoirs. However, the mechanism of the transportation of microcystin in lakes and reservoirs, especially, in micro-environment of the soil/water system is not yet clarified. The adsorption and photodegradation of microcystin poisoning could adversely affect the environment. Hence, the main purpose of this study was focused on the major factors that affect the transportation and fate of microcystin in natural water. The adsorption behaviour of microcystin was examined by collecting the soil/water samples from river or reservoir. The photodegradation of microcystin was studied by irradiating with different wavelengths of UV light. The adsorption and photodegradation of microcystin were examined by HPLC/UV techniques. The results of this study conveyed that the reservoir or river sediment, suspended solid and humic acid solution had an impact on the adsorption of microcystin and thereby affected the transportation and fate of microcystin. The adsorption of microcystin was found to be proportional to the distribution and composition of organic matter contents. When the soil/water systems contain more humic acid, the system of microcystin adsorption would increase and the larger content of humic acid solution resulted into greater poisoning of environment by microcystin adsorption. Analysis on the microcystin poisoning at the surface of sediment particles was also carried out. The results revealed that the larger adsorption of microcystin would lower the pH value of the system. The combination of both organic matter and sediment would necessarily enhance the adsorption of microcystin on the environment. The observation on photodegradation of microcystin explained that the generation of toxic microcystis pigments also affected the environment to a greater extent and poisoned the water system by releasing the coloring agents. Despite, the photodegradation was affected to some extent by suspended particles or humic acid in water, the irradiation of light had significant effect on this. Therefore, the adsorption and photodegradation of microcystin were clearly analyzed in this research for the better understanding of water pollution in the environment.
