川西北高原13种主要植物叶片的化学计量学特征分析

为探究川西北高原植物的生理适应特征,以川西北高原生态系统中13种主要植物为研究对象,分析其叶片的化学计量特征以及这些特征在海拔、生活型和植被类型等因素影响下的变化。结果表明,这13种植物叶片C、N和P含量分别为441.74、18.58和0.71 mg·g~(-1),C∶N、C∶P和N∶P分别为28.29、688.61和26.59。C、N、P含量之间,N∶P与C、N含量之间呈显著正相关(P0.05)。海拔、生活型和植被类型对植物叶片的化学计量特征影响明显,生长在高海拔样地的植物具有较高的C∶N和较低的N∶P,但不同植物对海拔梯度变化的响应不同;与草本植物相比,木本植物叶片具有更高的P含量,且其C∶N更低;8种生长于草地和灌丛草地植物的叶片N含量及N∶P均差异显著。本研究结果对当地生态系统管理和资源植物筛选等实践工作具有重要的指导意义。

Analysis of Chemical Metrological Characteristics of 13 Main Plant Leaves in the Northwestern Plateau of Sichuan

To better understand the physiological adaptation characteristics of plants in the Northwest Plateau of Sichuan,13 main plants in the North Sichuan Plateau ecosystem were employed as experimental materials,the chemical characteristics of the leaves were measured as well as the changes of these characteristics under the influence of altitude,life type and vegetation type.The results showed that the contents of C,N and P in the leaves of 13 species were 441.74,18.58 and 0.71 mg·g-1 respectively and the values of C:N,C:P and N:P were 28.29 688.61 and 26.59 respectively.There was typical P limitation to plants in Northwest Plateau of Sichuan.Significant positive correlation were observed between C,N and P,as well as N:P and C:N (P＜0.05).The effects of altitude,life type and vegetation type on the stoichiometric characteristics of plant leaves were found significant.The plants in relative high altitude had higher C:N ratio and lower N:P ratio,but the responses of different plants to altitude gradient were different.Compared with herbaceous plants,the leaf of woody plants had higher P contents and lower C:N ratio.Eight plant species were both collected in grassland and shrub grassland,their leaf N concentration and value of N:P were both significantly different.The results of this study are of great significance to the practice of local ecosystem management and resource selection.