华北地区油松林主要乔木物种叶片氮磷化学计量特征

植物体内特别是叶片N、P含量特征一直是植物生理生态学研究的一个热点。以内蒙古黑里河、北京松山、山西太岳山3个地区的油松林为研究对象,分析了油松和阔叶乔木叶片N、P化学计量特征。结果表明,13个乔木树种叶片N含量、P含量及N/P的范围分别为0.934 4%～4.898 7%、0.079 0%～0.655 5%、3.632 8～35.430 2;叶片N含量与P含量之间呈极显著正相关(r=0.589,P<0.01),而叶片P含量与N/P之间呈极显著负相关(r=-0.618,P<0.01);3个地区油松叶片N含量和P含量均低于阔叶树种叶片N含量和P含量,说明阔叶树种叶片具有较高的N、P储存能力;黑里河地区油松叶片的N/P显著小于阔叶乔木叶片N/P(P<0.01),而松山和太岳山地区油松叶片N/P与阔叶乔木叶片N/P的差异性不显著;油松叶片N含量和P含量的顺序均为太岳山>黑里河>松山,阔叶乔木叶片N含量和P含量的顺序均为黑里河>松山>太岳山,说明太岳山地区的油松具有更高的N、P储存能力,而黑里河地区的阔叶乔木具有更高的N、P储存能力。

Leaf nitrogen and phosphorous stoichiometry of trees in Pinus tabulaeformis Carr stands, North China

Nitrogen(N) and phosphorous(P) stoichiometry in plant leaves have been studied intensively with recent focus on large-scale patterns and driving mechanisms.An experiment was conducted in Hei Lihe of Inner Mongolia Autonomous Region,Song Mountain of Beijing and Taiyue Mountain of Shanxi Province to understand the N and P stoichiometry between Pinus tabulaeformis and broad-leaf trees in nature Pinus tabulaeformis Carr.Leaf stoichiometry showed large variations with N ranged from 0.9344% to 4.8987%,P from 0.0790% to 0.6555%,and N/P from 3.6328 to 35.4302.N and P were significantly and positively correlated(r=0.589,P<0.01),and P was significantly and negatively correlated to N/P(r=﹣0.618,P<0.01).N and P contents of Pinus tabulaeformis were lower than that those observed for broad-leaf trees in three sites.This implies that broad-leaf trees have higher N and P storage capacity than Pinus tabulaeformis.N/P in Pinus tabulaeformis and in broad-leaf trees differed significantly(P<0.01) in Hei Lihe.The mean concentrations of N and P for Pinus tabulaeformis ranked in the order of Taiyue Mountain> Hei Lihe> Song Mountain,while ranked as Hei Lihe> Song Mountain> Taiyue Mountain for broad-leaf trees.The result reveals that Pinus tabulaeformis has the high N and P storage capacity in Taiyue Mountain and that broad-leaf trees has high N and P storage capacity in Hei Lihe.