乌蒙山自然保护区十齿花林生态化学计量特征

Ecological Stoichiometry Characterization of Dipentodon sinicus Forest in Wumeng Mountain National Nature Reserve

以云南乌蒙山国家级自然保护区十齿花林为研究对象,利用单因素方差分析及多重比较等方法对其叶片、凋落物、土壤C、N、P含量及化学计量比进行分析,阐明十齿花林生态系统养分限制情况及养分循环特征。结果表明:十齿花林叶片、凋落物、土壤C平均含量分别为592.48、540.61、51.51 g·kg^(-1),N平均含量分别为19.41、15.45、1.66 g·kg^(-1),P平均含量分别为1.67、1.67、0.35 g·kg^(-1),各组分营养元素含量表现为叶片>凋落物>土壤;同一样地内植物叶片、凋落物和土壤C、N、P含量及化学计量比差异显著,不同样地土壤C、N、P含量及化学计量比、凋落物C含量差异显著,其余组分各指标差异不显著;叶片-凋落物N、C∶N显著相关,凋落物-土壤C显著相关;十齿花林生态系统主要受N素限制,凋落物的营养元素源于叶片,分解后归于土壤,为十齿花林生长发育提供养分支持,促进养分循环。

Taking the Dipentodon sinicus forest in Wumeng Mountain National Nature Reserve of Yunnan as the research object,Leaf,litter,soil C,N and P contents and stoichiometry ratios were analyzed using one-way analysis of variance(ANOVA)and multiple comparisons to elucidate the nutrient limitation and the characterization of nutrient cycling in the ecosystem of Dipentodn sinicus forests.The conclusion obtained were as follows:(1)The leaf,litter,soil C average content of 592.48,540.61,51.51 g·kg^(-1),N average content of 19.41,15.45,1.66 g·kg^(-1),P average content of 1.67,1.67,0.35 g·kg^(-1),the content of nutrients in each component were shown as leaf>litter>soil.(2)Plant leaf,litter and soil C,N and P contents and stoichiometric ratios varied significantly within the same plot,the content of soil C,N,P and litter C in the different plots was significantly different,while the indexes of other components were not significantly different.(3)The leaf-litter N content and C:N ratio,and litter-soil C content exhibited significant correlation.(4)Dipentodon sinicus forest ecosystems are mainly N-constrained,which are mainly limited by N elements,and the nutrients in the litter originate from the leaf and return to the soil after decomposition,providing nutrient support for the growth and development of Dipentdoon sinicus forests and promoting nutrient cycling.