三江平原小叶章湿地土壤硫的组成与垂直分布

Composition and Vertical Distribution of Soil Sulfur in Wetland Soil Under Calamagrostis angustifolia in Sanjiang Plain

以三江平原小叶章湿地为对象,对比研究了典型草甸小叶章湿地和沼泽化草甸小叶章湿地土壤硫的组成与垂直分布特征。结果表明,在2种小叶章湿地类型中,土壤总硫含量分别为303.39～520.83和303.74～1219.81mg·kg-1,平均值为391.62和513.03mg·kg-1,均低于世界平均土壤硫含量(700mg·kg-1)。硫主要富集在土壤表层,且主要以有机硫形式存在,有机硫占总硫比例约为90%,而在有机硫中,则以碳键硫所占比例最大,占总硫比例分别为45.34%和37.24%。沼泽化草甸小叶章湿地土壤各形态硫含量及其变异性均高于典型草甸小叶章湿地。在2种湿地土壤中各形态硫都具有明显的垂直分布特征和变异性。土壤有机质含量是影响硫含量的重要因素,同时也受到土壤各粒级含量的影响,并且土壤各形态硫含量之间存在一定的相关关系。

Characteristics of distribution and composition of sulfur in soils of typical meadow Calamagrostis angustifolia wetland and marsh meadow Calamagrostis angustifolia wetland in the Sanjiang Plain were studied. Results show that total sulfur in both wetlands are in the range from 303.39 to 520. 83 mg · kg^-1 and from 303.74 to 1 219. 81 mg · kg^-1 , respectively, averaging 391.62 and 513.03 mg · kg^-1 respectively, both lower than the average of the world soil. Sulfur accumulates mainly in the upper layer of the soils in the form of organic sulfur, which constitutes about 90% of total sulfur. Carbon-bonded sulfur forms the largest portion of organic sulfur, accounting for 45.34% and 37.24%, respectively in the wetlands. The marsh meadow Calamagrostis angustifolia wetland is higher than the typical meadow Calamagrostis angustifolia wetland in both the content and variability of soil sulfur of various forms. In the two kinds of wetlands, all forms of sulfur displayed obvious characteristics of vertical distribution and variability. Content of organic matter in the soil is the important factor affecting the content of sulfur, which is also affected by contents of soils of various particle size fractions. Moreover, the contents of soil sulfur of various forms are also correlated with each other.