近年来，我国有毒甲藻赤潮的暴发频率和影响面积呈增加态势，给海洋生态系统和近海养殖业造成极大危害。改性粘土可有效的治理有害赤潮，在短时间内絮凝沉降水体中大部分藻细胞，并对水体中残留的部分藻细胞产生胁迫作用抑制其增殖。尽管前期已对改性粘土治理赤潮的生态环境效应开展了大量的研究工作，但针对有毒甲藻赤潮，改性粘土治理过程对水体中残留藻细胞的产毒能力的影响作用、沉积絮体中藻毒素的归宿一直是人们特别关注的问题。本项目针对改性粘土方法治理有毒甲藻赤潮目前所存在的科学问题，选择我国沿海常见的有毒甲藻-亚历山大藻为研究对象，通过开展改性粘土治理赤潮方法对水体中残留藻细胞产毒能力、沉积絮体中藻毒素归宿及其主要影响因素等方面的研究，阐明利用改性粘土治理赤潮方法对甲藻产毒能力、藻毒素归宿以及治理后毒性的影响作用，揭示影响上述过程的关键因素及作用机制，为近海养殖水域有毒甲藻赤潮的治理提供科学依据。

In recent years, the frequency and impact area of the toxic dinoflagellate red tide in China have increased, which has caused great harm to marine ecosystems and offshore aquaculture. The modified clay (MC) can effectively treat the harmful red tide, flocculate most of the algal cells in the water column in a short time, and exert stress on the remaining residual algae cells in the water column to inhibit its proliferation. Although a lot of research works have been carried out on the eco-environmental effects of MC to flocculate red tides, the impacts of MC treatment on the toxin production ability of residual algae cells in the water column and the fate of algal toxins in the sedimented flocs have always been a matter of particular concern. This project is aimed at the scientific problems existing in the treatment of the toxic dinoflagellate red tide by the MC method. The common toxic dinoflagellate- Alexandrium spp. in the coastal area of China was selected as the research organism. The researches of toxin production ability of residual algal cells in the water column and the fate of algal toxins in the sedimented flocs will be carried out after using MC to treat the Alexandrium spp. The results will help us to clarify the key scientific issues such as the toxicity of dinoflagellates, the fate of algal toxins, and the toxic effects after treatment. And furthermore, to reveal the key factors and mechanism of the above process, and then provide a scientific basis for the treatment of the toxic dinoflagellate red tide in offshore aquaculture waters.