有害藻类暴发是当前全球湖泊面临的重大环境问题，直接威胁着水生生物多样性和流域居民供水安全。识别藻类群落动态变化规律及藻类暴发机理是湖泊管理的关键。传统古湖沼学和沉积物DNA的综合分析在藻类群落演替历史重建中具有显著的优越性，而国内鲜有报道。本研究拟选择太湖梅梁湾（藻型湖区）和东太湖（草型湖区）为对象，基于现代沉积过程和水体监测数据的分析，评估沉积物藻类色素和DNA指标的代表性和有效性；通过沉积钻孔高分辨率的DNA和色素分析，重建近百年来真核浮游藻类和蓝藻群落结构演替历史。运用排序分析和广义相加模型（GAM）等多元统计分析手段，探讨太湖“藻型”和“草型”湖区浮游藻类对温度、营养盐、水文等驱动力变化的响应特征及差异，并定量区分过去百年来不同时期人类活动和气候变化对藻类群落的影响份额。本研究有望进一步细化有害藻类群落暴发特征与机理，将为深入理解太湖水生群落衰退历史成因和机制提供科技支撑。

Harmful algae blooms are a major environmental problem in freshwater lakes around the globe, which directly threaten the aquatic biodiversity and human water security. Understanding the dynamics in algal communities and the underlying mechanism of algal blooms are crucial for lake management. The combination of sediment ancient DNA (SedaDNA) and traditional paleolimnological techniques has significant advantages in the historical reconstruction of algal community succession. However, palaeoecological study on this issue are scare. In the present research, Meiliang Bay (algae-dominated) and Eastern Taihu Lake (macrophyte-dominated) are considered as case study. The representativeness and effectiveness of algal pigments and DNA proxies in the sediments will be evaluated based on the comprehensive analysis of modern sedimentation process and water monitoring records. The community structural succession history of eukaryotic algae and cyanobacteria over the past 100 years will be reconstructed by high-resolution analyses of SedaDNA and pigments in the cores. The historical response of different algae to changes in temperature, nutrient and hydrology will be explored using ordination analyses and generalized additive model (GAM) in algae and macrophyte dominated zones from Taihu Lake. Furthermore, this study will partition out the effects of anthropogenic and climate factors on algal community during different periods over the past 100 years. The outputs from this study will be of important implications for further revealing the characteristics and mechanism of harmful algae blooms, and will also provide scientific basis for deeper understanding towards the historical cause and mechanism of the degradation in aquatic communities from Taihu lake.