为研究复合垂直流人工湿地系统净化海水养殖尾水过程中氮的降解规律，利用一级动力学模型，模拟了TDN（总溶解性氮）、DON（溶解性有机氮）和3种DIN（溶解性无机氮）在人工湿地系统中的降解特征，并通过PCR-DGGE（变形梯度凝胶电泳）技术分析了氮降解与系统中微生物的群落结构和组成的关系。结果显示：海水养殖尾水中各形态氮的降解均符合一级动力学特征（R2≥0.70），降解速率依次为DIN>TDN>DON，去除速率常数分别为0.10 h-1，0.09 h-1和0.03 h-1；DIN各组分中，降解速率依次为NH4+-N>NO2--N>NO3--N，去除速率常数分别为0.15 h-1，0.11 h-1和0.09 h-1。基质层以及植物根部与脱氮相关的细菌组成丰富，说明在氮去除过程中微生物发挥着至关重要的作用。其中，主要的优势菌门为变形菌门(34.46%)、蓝细菌门(12.78%)、放线菌门(10.55%)、绿弯菌门(10.46%)和拟杆菌门(7.78%)。研究结果将为揭示海水人工湿地的除氮机理提供理论依据。

In order to study the degradation of nitrogen in the process of purifying tailwater of mariculture by integrated vertical-flow constructed wetland system, the degradation characteristics of TDN, DON and three forms of DIN in the constructed wetland system were simulated using the first-order kinetic model, and the relationship between nitrogen degradation and the community structure and composition of microorganisms in the system was analysed by the PCR-DGGE technique. The results showed that the degradation of various forms of nitrogen in tailwater of mariculture conformed to the first-order kinetic characteristics (R2≥0.70), with the degradation rate in the order of DIN> TDN> DON, and the removal rate constant of 0.10h-1, 0.09h-1 and 0.03h-1 respectively; among the components of DIN, the degradation rate was in the order of NH4+-N> NO2--N> NO3--N, and the removal rate constant was 0.15h-1, 0.11h-1 and 0.09h-1 respectively . Bacteria related to denitrification were rich in the substrate layer and around the plant roots, indicating that microorganisms played a vital role in the nitrogen removal process. Among them, the main dominant bacteria were Proteobacteria (34.46%), Cyanobacteria (12.78%), Actinomycetes (10.55%), Campylobacter (10.46%) and Bacteroides (7.78%). The research results will provide a theoretical basis for revealing the nitrogen removal mechanism in seawater constructed wetlands.