陈旗退化喀斯特森林群落常见植物叶片氮磷元素含量变异特征

Variation Characteristics of N and P Contents in Leaves of Common Plant Species in Degraded Karst Forest Community of Chenqi Catchment

以陈旗退化喀斯特森林群落4种典型植物为研究对象,测定植物叶片N、P元素含量,分析元素含量间的变异特征。结果表明:流域内常见植物叶片的N、P元素含量分别为11.71~30.51、0.37~0.83 mg/g,平均值分别为18.48和0.66 mg/g;流域内小叶鼠李、火棘、竹叶花椒、小果蔷薇植物叶片N/P值均大于16,生长主要受P限制,均属P制约型植物;植物叶片N、P元素含量在流域内不同种间的差异均显著(P<0.05);植物叶片N元素含量在不同演替阶段植物群落不同种间的差异均显著,P元素含量在乔灌过渡林和乔木林的不同种间差异显著,但在稀灌草丛、藤刺灌丛、灌木林的不同种间差异不显著;植物叶片N元素含量在不同演替阶段植物群落间均有显著差异,P元素含量在不同演替阶段植物群落间均无显著差异;N元素含量受植物种和群落类型的交互影响显著,P元素含量受植物种和群落类型的交互影响不显著。该研究结果有助于理解植物养分限制状况,为退化生态系统修复提供数据支持。

This paper,taking four typical plant species of degraded karst forest community in Chenqi catchment as the research objects,measured the contents of N and P elements in plant leaves,and analyzed the variation characteristics of the elements among different plant species and communities.The results showed that:(1)the contents of N and P in the leaves of common plants in the catchment was 11.71-30.51 mg/g and 0.37-0.83 mg/g,respectively with an average of 18.48 mg/g and 0.66 mg/g;(2)Rhamnus parvifolia,Pyracantha fortuneana,Zanthoxylum armatum and Rosa cymosa were all over 16 in the leaf N/P ratio,and their growth was mainly restricted by P,belonging to P-restricted plants;(3)there were significant differences in leaf N and P contents between species within the catchment(P<0.05);(4)there were significant differences in leaf N element content between species of the plant communities in different succession stages(P<0.05);there were significant differences in P element content between species of the arbor and shrub transitional forest and the arbor forest(P<0.05),but no significant differences between species of the thin shrubgrassland,the vine-shrubberry,and the shrubberry(P>0.05);(5)between plant communities in different succession stages,there were significant differences in leaf N element content(P<0.05),while P element content had no significant differences(P>0.05);(6)N element content was significantly affected by the interaction between plant species and community types(P<0.05),but P element content was not(P>0.05).The research results help to understand the nutrient limitation status of plants,and provide data support for the restoration of degraded ecosystems.