鄱阳湖南矶山湿地土壤养分的时空分布规律研究

通过研究鄱阳湖南矶山湿地土壤在不同季节、不同植被类型和不同土壤深度下总有机碳、总氮、总磷的含量变化,分析了鄱阳湖南矶山湿地土壤养分的空间分布特征和季节变化规律。结果表明:南矶山湿地土壤总有机碳、总氮、总磷含量在不同的土壤深度、季节和植被类型中均表现出极显著差异。其中南矶山灰化苔草、南荻、狗牙根植被群落样地0~15cm表层土壤总有机碳、总氮含量显著大于30~45cm底层含量;灰化苔草、南荻群落土壤总有机碳和总氮含量的季节变化明显,尤其是表层土壤在各个不同的季节差异显著,但狗牙根植被群落土壤总有机碳和总氮含量季节变化不明显;3种典型植被类型下土壤总磷含量季节变化明显,呈现"N"的变化趋势。土壤总有机碳与总氮含量极显著正相关、与总磷含量显著相关,表明鄱阳湖南矶山湿地土壤氮、磷主要以有机质的结合形态存在。

Temporal and Spatial Patterns of Soil Nutrients in the Wetland of Nanjishan(Poyang Lake), China

To investigate the temporal and spatial distribution characteristics of soil nutrients in the Nanjishan wetland, soils from three typi- cal zones, which covered Carex cinerascens, Triarrhena lutarioriparia and Cynodon dactylon, were collected in five seasons from June 2009 to January 2011 and in three depth(0～15 cm, 15～30 cm and 30～45 cm). The contents of total organic carbon(TOC), total nitrogen(TN)and total phosphorus(TP)were analyzed. Results showed that there were distinct differences in TOC, TN and TP contents among soil depths, sampling seasons and vegetation types of Nanjishan wetland. The TOC and TN contents of surface layer(0～15 cm)soil were remarkably greater than the underlying layer′s(30～45 cm)in all sites. The TOC and TN contents of the soil in the sites of Carex cinerascens, Triarrhera lutarioriparia, not including Cynodon dactylon, had a close relationship with the variable of season. Especially the difference of TOC and TN content of surface soil in the different seasons was remarkable; the soil TP content from all sites remarkably changed with seasons, with a"N" trend. Additionally, TOC contents of soil had a significantly positive correlation with TN, and a correlation between TOC and TP contents was also detected, but there was no correlation between TN and TP.