江西官山2种苔藓植物叶片氮磷化学计量学特征

The leaf nitrogen: phosphorus stoichiometry of two bryophyte species in Guanshan Mountain, Jiangxi Province

氮(N)、磷(P)化学计量学特征对植物的生长发育及适应能力至关重要,苔藓植物属古老的植物类群,能够长期适应自然环境的变化,但其氮磷化学计量学特征及适应机制尚不清楚。本文在江西省官山国家级自然保护区选择2种典型苔藓植物地钱(Marchantia polymorpha)和大灰藓(Hypnum plumaeforme),并以2种被子植物寒莓(Rubus buergeri)和木荷(Schima superb)为对照,比较分析了叶片的N、P含量、N∶P和变异系数等指标。结果表明:(1)与2种被子植物相比,苔藓植物P含量较高,N∶P较低,其叶片P含量平均值为2.58 mg/g显著高于被子植物的1.97 mg/g,而其叶片N∶P的平均值则为5.99显著低于被子植物的8.35;(2)苔藓植物体内的养分变幅较大,其叶片N、P、N∶P的变异系数分别为18.94%、22.05%和18.52%均高于被子植物的13.16%、10.69%和13.00%。以上结果说明,苔藓植物具有较高的P含量、较低的N∶P,并有较强的可塑性,其生态适应性与环境改造功能有待深入研究。

Nitrogen（N） and Phosphorus（P） stoichiometry is crucial to plant growth, development and adaptive capacity.Bryophytes belong to ancient plant groups, can adapt to the change of the natural environment for a long time. However, The leaf N and P stoichiometry and adaptation mechanism for bryophytes are still unclear. In this study, two typical bryophytes（Marchantia polymorpha, Hypnum plumaeforme） and two kinds of angiosperms（Rubus buergeri, Schima superba） which as a control were selected in Guanshan National Nature Reserve, Jiangxi province, then comparatively analyzed the leaf N and P content, leaf N∶P and coefficients of variation and so on. Results showed that：（1） Bryophytes leaf P average content was 2.58mg/g, significantly higher than that was 1.97 mg/g in two angiosperms, while leaf N ∶P average was 5.99, obviously lower than8.35 of angiosperms.（2） The variation range was great of leaf N, P and N ∶P in bryophytes, whose variation coefficients were18.94%, 22.05% and 18.52%, respectively were higher than 13.16%, 10.69%, and 13.00% of angiosperms. Above results indicated that bryophytes owned high P content, low N ∶P and had strong plasticity, we suggest that the ecological adaptation and environmental transformation function of bryophyte should be continue to study in depth.