水陆交错带土壤氮素空间分异规律研究——以月亮泡水陆交错带为例

研究了氮素在水陆交错带的水平和垂直分异规律。结果表明表层土壤氮素水平分异显著高于下层（NH4^ －N除外）且随水分梯度分异；表层土壤各形态氮素含量基本上呈由近水体向高岗地带递减的分异趋势；但下层土壤氮素分异因形态不同而异，NO3^-－N含量由中间带向两侧递减，NH4^＋－N变异方向则与表层变异相反，K－N、OR－N与TN分异趋势相似且与表层变异一致；NO3^-－N因具有迁移性和易淋失性而使其空间分异最为显著；NH4^ －N较稳定，易被土壤胶体所吸附不易向下淋失，空间分异程度最小；K－N、OR－N与TN垂直分异趋势也具相似性；水陆交错带湿地土壤中的氮素含量与SOM和TP密切相关，而pH值对氮素分异的影响则不太显著。

Study on the laws of spatial variation of nitrogen in soil of land/inland water ecotones-A case of LWE in Yueliangpao wetland

The spatial variation of land/inland water ecotones(LWE)in the horizontal and vertical directions were studied. The results showed that the variation of nitrogen content in surface soil was greater than that in subsurface soil(except for NH + 4 N) and approximately varied with the moisture gradient; however, to subsurface soil, the variations of all forms of nitrogen were obviously different, i.e. NO - 3 N decreased from the middle to both sides, the variation of NH + 4 N was opposite to that in surface soil, and the tendency of variation of K N,OR N and TN was similar and consistent with that in surface soil; the spatial variation of NO - 3 N was the most distinct because it is easy to be removed and leached; NH + 4 N was easy adsorbed by the soil colloid and difficult to be leached, so its variance was the smallest, the pattern of spatial distribution of K N,OR N and TN was similar, LWE coued filtrate nitrogen in soil and the content of nitrogen strongly correlated with SOM and TP, however, was not distinctly influenced by pH value.