Silicon (Si), the second-most abundant element in the earth’s crust (28.8%) behind oxygen, is essential nutrient for hydro-phytes (especially diatom) and crops. Si is also important element to control the functions of terrestrial, marine, coastal and inland water ecosystems. However, little is known about Si cycling processes in the wetland ecosystem, espeically in China. Here we sum-marize Si chemical forms, distribution and rough biogeochemical cycle in diverse wetlands. Different impact factors, including wet-land types, flooding event, seasonality anthropogenic activity, and carbon cycle, are discussed. We also address mechanisms of trans-ference and transformation and clarify Si cycling, storage, and sink in estuary and coastal marshes. Hydrological model simulations with key parameters of drainage, evaporation, flooding frequency and residence time are critical to understand the impacts of wetland Si cycle on eutrophication in coastal zone and global climate changes.%硅在地壳中的丰度仅次于氧，是地球表面大多数土壤和岩石的一种基本成分，也是水生植物（特别是硅藻类）以及多种作物生长所必需的营养元素，还是控制陆地、海洋、沿海和内陆水生态系统机能的重要营养元素。目前关于全球硅的生物地球化学循环的研究多集中在陆地和海洋两大生态系统，而湿地生态系统中硅的循环过程、储存量尚不清楚。虽然在河口湿地开展一些关于硅的相关研究，但是硅在湿地的循环机制研究不够全面，尤其相比碳、氮、磷等元素，硅素研究甚少。而且，国内关于硅的相关研究更为匮乏。本文在总结国内外关于湿地生态系统硅素研究的基础上，综述硅在湿地生态系统的存在形态与分布特征，阐述硅在湿地生态系统中的基本循环过程，列举影响硅在湿地生态系统中循环的主要因素，如：湿地类型、水淹时间、季节变化、人类干扰等；提出在今后研究工作中应进一步探索硅在湿地生态系统中迁移、转化的机制，加深研究人类活动对湿地生态系统硅循环的影响，特别是应该加强研究河口潮汐湿地和沿海湿地生态系统硅的生物地球化学循环过程和储存量，有助于明确湿地生态系统对于硅的截留量；并弄清湿地中碳与硅含量之间的关系，从水文学角度分析湿地中排水、蒸发、洪期及滞留时间等因素对硅循环的影响，从而试图建立湿地硅循环模型，有助于预测湿地生态系统硅循环对沿海地区赤潮等富营养化现象和全球气候变化的影响。
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