摘要:氮素是构成一切生命体的重要元素，以不同形态存在于大气圈、岩石圈、生物圈和水圈中。近年来，氮素对全球环境变化的重要影响日益凸显，研究领域涉及水、土、气、生。为了描述陆地生态系统氮循环过程、模拟气候变化和人类活动对氮循环过程的影响，本课题选定典型生态系统类型（湿地），实地测量植被氮库、土壤氮库和氮的流失量，搜集氮循环模型，根据输入、输出研究影响氮循环的因素和相关过程的空间分布规律，为从源头上解决水体富营养化问题提供必要且有效的技术保障，取得良好的经济效益和社会效益。

关键词：人工湿地，氮循环，模拟，脱氮技术

Abstract:Nitrogen is an important element in all organisms, existing as different forms in the atmosphere, lithosphere, biosphere and hydrosphere. In recent years, the effects of nitrogen on global changes have become obvious increasingly. Many studies focused on the investigation of water, soil, atmospheric and biological. In order to describe the process of nitrogen transformation in terrestrial ecosystems, simulate climate change and impacts of human activities on the nitrogen transformation, this paper measured the nitrogen concentration in the plants, soil, waters and so on in the constructed wetlands. According to the nitrogen transformation models studied in literatures, a modified model was constructed based on the input and output nitrogen concentration in the ecosystems. Some factors affecting the nitrogen transformation were compared. This study may be helpful for solving the problem of Lake Eutrophication and achieving good economic and social benefits.

Keywords: Constructed wetland, Nitrogen transformation, Simulation, Nitrogen removal

　　　人工湿地是指人工建造和监督控制的，类似于沼泽的地面，其设计是通过对湿地自然生态系统中的物理、化学和生物作用的优化组合，利用这3种作用的协调关系来实现污水的净作用。水体、基质、植物和微生物是构成人工湿地污水处理系统的4个基本要素。基质在为植物和微生物提供生长介质的同时，也能够通过沉淀、过滤和吸附等作用直接去除污染物。大型湿地植物既是微生物的 “固定化载体”，氧气的生产和运输“机器”，同时还能够稳固湿地床表面，起到冬季保温和支撑冰面的作用。微生物是消除污染物的作用者，它能够在去除氮、磷等营养物的同时把有机质作为丰富的能源转化为营养物质和能量。