长白山森林不同演替阶段植物与土壤氮磷的化学计量特征

N and P stoichiometric traits of plant and soil in different forest succession stages in Changbai Mountains

以长白山森林不同演替阶段的典型群落为对象,研究了不同层次优势种茎和叶化学计量特征及其与土壤因子的关系,并对不同演替阶段群落化学计量进行了比较.结果表明:叶氮浓度(LNC)与叶磷浓度(LPC)、茎氮浓度(SNC)呈极显著正相关,与茎磷浓度(SPC)显著正相关;LPC与SNC呈显著正相关,与叶N/P、茎N/P显著负相关;叶N/P与茎N/P呈极显著正相关;SNC与SPC呈极显著正相关;SPC与茎N/P呈极显著负相关.各演替群落间的乔木层化学计量特征均有显著差异,灌木层除了叶N/P差异显著以外,其他指标均无显著差异;随演替的进行,LNC明显增加,而LPC呈减少趋势.通过RDA约束排序分析发现,演替前期植物群落主要受氮素的影响,演替中后期主要受氮磷共同影响,以磷素的作用更为强烈.

The typical forest communities under four different succession stages in Changbai Mountains were selected to study the stoichiometric traits of stems and leaves of dominant species in different layers, and the relationships between these stoichiometric traits and terrain factors. The results showed that leaf nitrogen content （LNC） was significantly positively correlated with leaf phosphorus content （LPC） and stem nitrogen content （SNC）, and positively with stem phosphorus content （SPC）. The LPC was positively correlated with SPC and negatively with leaf N/P, stem N/P. The leaf N/P was positively correlated with stem N/P. SNC was positively correlated with SPC. There were significant differences in the stoichiometric traits of the plant species at tree layers among the different succession forest communities, while no obvious difference in shrub layers except for leaf N/P. Based on RDA analysis, it indicated that the plant communities in the Changbai Mountains is N-affected in the primary stage of succession, while N- and P-affected in the mid and later stages with a stronger impact from P.