中文摘要：

采用分解袋法，以我国东南沿海典型的感潮河口——闽江河口最大的鳝鱼滩湿地为研究区域，选取2个潮水水淹环境差异显著的地段（一个为近潮沟地段，另一个为远潮沟地段）为研究样地，对闽江河口主要的本地种芦苇、短叶茳芏及外来入侵种互花米草枯落物分解过程及影响因素进行研究，结果表明：（1）经常性的潮汐水淹对3种植物枯落物分解速率的影响不显著；（2）经常性的潮汐水淹促进了短叶茳芏和互花米草枯落物N、P元素的损失，但对芦苇的影响不大；（3）在2种不同的水淹环境，3种植物枯落物分解速率由快到慢的顺序均是短叶茳芏〉互花米草〉和芦苇，分解速率在0．003166～0．005280d^-1之间，95％干物质分解需要的时间在1．56～2．61a之间；（4）C浓度基本稳定，N浓度呈上升趋势，总N在研究末期表现为净损失，P浓度呈较大的波动，总P在研究末期也表现为净损失；（5）具有最低C／P的短叶茳芏枯落物分解速率最快。

英文摘要：

Decomposition of litter plays an important role in carbon turnover and nutrients cycling in wetland ecosystem.Tide is the key feature for the estuarine tidal wetland.The wetlands of the Minjiang River estuary region are one of the major estuarine tidal wetlands in the southeast of China,and the Shanyutan is the largest wetland in the Minjiang River estuary region.Litter decomposition,nutrient dynamics and influencing factors of two native species（Phragmites australis and Cyperus malaccensis） and one exotic invasive species（Phragmites australis） were studied using mesh bag method in two sites under different tidal water submergence conditions.One site was near the tide ditch,and the other is far from the tide ditch in central Shanyutan wetland. The results indicated that：（1） Frequent tidal water submergence had no significant effects on the litter decomposition rates of three plants.（2） Frequent tidal water submergence accelerated the N and P loss of Cyperus malaccensis and Spartina alterniflora,however,it had little effect on Phragmites australis.（3） The order of litter decomposition rate was Cyperus malaccensis〉Spartina alterniflora〉Phragmites australis,with rates of 0.003166-0.005280 d 1,and the time of 95% dry mass of litter loss ranged from 1.56 to 2.61a.（4） C concentrations had only a little change,and the major pathway of C release was mineralization during the 280 days;there was an upward trend in N concentrations,at the end of the experiment,N content had a net loss and the major pathway of loss was mineralization;there was an obvious fluctuating downward trend in P concentrations at the end of the experiment,P content had also a net loss and leaching losses were responsible for much of P loss.（5） Litter quality was a main factor influencing the litter decomposition rates of the three plants.Litter decomposition rate of Cyperus malaccensis with the lowest C/P was the greatest.