Although sediment deposition is an important process in coastal marshes, insufficient information is available about its influence on litter decomposition and nutrient cycle. In order to investigate the potential impacts of sediment deposition on nutrient (carbon (C), nitrogen (N), phosphorus (P) and sulfur (S)) variations in typical detritus (Cyperus malaccensis) in coastal marsh of the Min River estuary (Southeast China), the field decomposition experiment was conducted during 2016 ~ 2017 which included three one-off deposition treatments: no sediment deposition (0 cm yr⁻¹, NSD), current sediment deposition (5 cm yr⁻¹, CSD) and strong sediment deposition (10 cm yr⁻¹, SSD). Results indicated that sediment deposition showed significant effect on litter decomposition rate, following the order of NSD (0.00735 d⁻¹) > CSD (0.00508 d⁻¹) > SSD (0.00378 d⁻¹) (p < 0.05). The total carbon (TC) contents in decaying litters in the CSD and SSD treatments were significantly higher than those in the NSD treatment (p < 0.05). The contents of total nitrogen (TN) and total sulfur (TS) in decomposing detritus in the three deposition treatments generally showed an increasing trend during 0 ~ 276 days, while those of total phosphorus (TP) showed increasing tendency after decomposing for 30 days. With increasing deposition depths, the contents of TC, TN, TP or TS in decaying litters generally increased. The differences in decomposition rates and nutrient contents among the three deposition treatments primarily rested with the alterations of substrate quality in decaying detritus during the whole decomposition. Stocks of C, N, P and S in decomposing litters in the three deposition treatments evidenced the export from detritus to the surroundings and, with increasing deposition depths, the nutrient released from detritus decreased greatly. This paper found that strong sediment deposition reduced the nutrient return (particularly for S) from detritus, which, in turn, might greatly alter the nutrient cycle in C. malaccensis marsh.

尽管沉积物沉积是沿海沼泽的一个重要过程，但关于其对凋落物分解和养分循环的影响的信息不足。为了研究泥沙沉积对闽江口沿岸沼泽典型碎屑（Cyperus malaccensis）养分（碳（C）、氮（N）、磷（P）和硫（S）变化的潜在影响，东南地区），于2016年~2017年进行了野外分解实验，包括3次一次性沉积处理：无沉积物（0 cm yr ^-1，NSD）、现沉积物（5 cm yr ^-1，CSD）和强沉积物。沉积物沉积（10 cm yr ^-1，SSD）。结果表明，沉积物沉积对凋落物分解率有显着影响，影响大小依次为NSD (0.00735 d ^-1 ) > CSD (0.00508 d ^-1 ) > SSD (0.00378 d ^-1 ) ( p <  0.05)。CSD 和 SSD 处理中腐烂凋落物中的总碳（TC）含量显着高于 NSD 处理（p <  0.05）。3种沉积处理的分解碎屑中总氮(TN)和总硫(TS)含量在0~276 d内普遍呈现增加趋势,而总磷(TP)含量在分解30 d后呈现增加趋势。随着沉积深度的增加，腐烂凋落物中TC、TN、TP或TS的含量普遍增加。三种沉积处理的分解速率和养分含量的差异主要取决于腐烂碎屑在整个分解过程中基质质量的变化。三种沉积处理中分解凋落物中的C、N、P和S储量证明了碎屑向周围环境的输出，并且随着沉积深度的增加，碎屑释放的养分大大减少。本文发现，强烈的沉积物沉积减少了碎屑的养分返回（尤其是硫），这反过来又可能极大地改变马六甲沼泽的养分循环。