向海湿地不同植物群落下土壤有机质和全磷的空间分布特征

Spatial Distribution of Organic Matter and Total Phosphorous in Marsh soils With Different Plant Communities in Xianghai Wetland

通过对比分析向海湿地8种植被群落下表层和亚表层土壤有机质和全磷含量差异,研究了不同植被群落下湿地土壤有机质和全磷的空间分异特征。研究结果表明,芦苇群落、芦苇—沼柳群落和香蒲群落下表层土壤有机质和全磷含量均高于其它植物群落;根系分布较浅的碱草群落、三棱群落和碱蓬群落下亚表层土壤有机质和全磷含量较低,且碱蓬群落亚表层土壤有机质和全磷含量显著低于其它植物群落。除芦苇群落和辣蓼群落外,其它群落下表层土壤有机质含量均高于亚表层土层;对于全磷而言,除辣蓼群落外,其它各植物群落下表层土壤群落下土壤全磷含量均高于亚表层土壤。湿地土壤全磷含量随有机质含量的增加呈幂函数增长变化;土壤有机质含量随土壤C/N比和pH值的增加呈幂函数增长和指数衰减函数变化,但土壤全磷与二者之间的函数关系未达到显著性水平。

Contents of organic matter and total phosphorous in surface and subsurface soils with eight different plant communities in Xianghai wetland were measured in order to study the spatial variability of soil organic matter and total phosphorous in marsh soils with different plant communities.Results showed that contents of soil organic matter and total phosphorous were higher in surface soils with these communities such as Phragmites cmmunis,Phragmites-Salix community and Typha community than those in other vegetation communities.They were lower in subsurface soils with Aneurolepidium chinense,Suaeda acuca,Sparganium stotoniferum with shallower root systems,and significantly lowest in surface soils with Suaeda acuca communities.Except these soils with Phragmites cmmunis and Polygonum hydropiper,soil organic matter contents were higher in surface soils with other plant communities than those in subsurface soils.Similarly,total phosphorous contents were higher in surface soils than those in subsurface soils except those soils with Polygonum hydropiper communities.Total phosphorous contents increased by power function with increasing soil organic matter contents.Also,soil organic matter contents increased by power function with the increases in C/N ratios and they exponentially decreased with the increases in soil pH values.However,the relationships between total phosphorous and C/N ratios and pH values did not show significant levels.