互花米草盐沼土壤有机质分布特征

Distributing Character of Soil Organic Matter in Salt Marsh of Spartina alterniflora Loisel

互花米草是我国从美国引进的外来物种，目前在我国沿海已形成大面积的互花米草盐沼，对潮滩土壤等环境产生重大影响。为了分析互花米草盐沼土壤有机质的分布特征，本文通过对江苏东台沿海不同地点（生长年数）的互花米草盐沼土壤样品的有机质含量分析，发现互花米草盐沼在由海堤向外的水平方向上变化的平均梯度为每100 m 土壤有机质含量减少 0.87 g/kg，垂直方向上的平均梯度为每向下 1 cm 土壤有机质含量减少 0.05 g/kg。互花米草盐沼土壤有机质的含量与互花米草生长年数相关程度较高，而与植株的生长状况相关较低。

Spartina alterniflora Loisel is introduced from the U. S. A. to China and it is an adventitious species of plant to Chinese environment. Spartina alterniflora Loisel can occupy vast areas between mean sea level and mean high level, and it has influenced the coast environment deeply. In order to obtain the distributing character of the soil organic matter in the salt marsh of Spartina alterniflora Loisel, 8 deepness level soil samples on five spots on Jiangsu Dongtai tidal flat are collected, and the soil organic matter in the samples are analyzed, and it is found that, on the average the soil organic matter decreases 0.87 g/kg outward every 100 m, and decreases 0.05 g/kg downward every 1 cm. It is also found that the soil organic matter in the salt marsh of Spartina alterniflora Loisel has high correlation with its growth age, and has little correlation with its growth status.