摘要
为了研究青海云杉叶片养分随环境的变化特征,通过测定贺兰山海拔梯度上的青海云杉针叶碳、氮、磷含量,研究不同海拔青海云杉叶片C、N、P的变异特征,同时探讨叶片C、N、P含量及其计量比与环境因子的关系,为进一步探讨植物对环境的响应提供科学依据。结果显示:(1)随着海拔升高、温度的下降以及降水的逐渐增加,青海云杉叶片C含量没有显著的变化,叶片N含量随海拔梯度显著下降。而叶片P随海拔梯度波动较大但并没有表现出明显的下降趋势,只是在海拔为2810m之后,P含量显著降低,C:N随着海拔的升高而升高,由于叶片P含量波动,使C:P和N:P的比值均表现先降低后迅速升高的趋势。(2)本研究青海云杉叶片C、N、P含量及C:N、C:P及N:P值的变异系数均小于30%,其大小排序为P(27.03%)>C:P(26.74%)>N:P(19.19%)>C:N(12.44%)>N(12.33)>C(1.07%)。(3)青海云杉叶片N、P含量及N:P比值相比于其他研究处于较低的水平。因此,在海拔梯度上,优势树种青海云杉叶片C含量受影响不大,而N、P含量随环境变化较大;较低的N:P值说明贺兰山青海云杉在生长中主要受N的限制。
In this study, Leaf carbon （ C ）, nitrogen （N） and phosphorus （P） of Picea crassifolia were investigated along altitude gradient in west slope of Helan Mountains in August, 2007. Our objective was to examine the relationship between leaf stoichiometric along environmental gradient and environmental factoers, and provided theoretical evidence for discussing the response of plants to environmental change. The results showed that： （ 1 ） Across the 2220 -3060 altitude gradient,leaf C showed no obvious correlation along altitude; leaf N decreased with altitude increase; leaf P showed no clear pattern below 2810 m and then decreased with increasing altitude. While C：N ratio increased obviously,but C：P and N：P ratios dropped first and then rose with the latitude increase. （2） In our study, the coefficient of variation （CV） for leaf C, N and P content, C ： N, C ： P and N ： P were less than 30%, and the order was P （ 27.03 % ） 〉 C ： P （26.74 % ） 〉 N ： P （ 19.19 % ） 〉 C ： N （ 12.44% ） 〉 N（12.33） 〉 C（ 1.07% ）. （3） leaf C,N and P stoichiometry were ranged from 459.69 to 486.42mg · g-1 for C,from 9.50 to 15.12mg · g-1 for N and from 0.74 to 1. 70mg · g-1 for P. At interspecifie level, both leaf N and P of Picea crassifolia folia were lower than those of most other research tree species. Hence, it is an adaptive selection that contents of leaf N, P changed with environmental change and altitude gradients, and Picea crassifolia was more limited by nitrogen, rather than phosphorus.
出处
《干旱区资源与环境》
CSSCI
CSCD
北大核心
2017年第6期185-191,共7页
Journal of Arid Land Resources and Environment
基金
国家重点研发计划(2016YFC0500506
2014CB138703)
高等学校博士学科点专项科研基金(20120211110029)
国家科技基础性工作专项(2012FY111900)
国家自然科学基金(31572458
31201837)
长江学者和创新团队发展计划(IRT13019)
兰州大学中央高校基本科研业务费专项资金(lzujbky-2015-190
lzujbky-2016-13)资助
关键词
贺兰山
青海云杉
海拔梯度
环境因子
生态化学计量学
Helan Mountains
Picea crassifolia
altitude Gradient
environmental factor
stoichiometry
