Chin J Plant Ecol ›› 2019, Vol. 43 ›› Issue (12): 1048-1060.DOI: 10.17521/cjpe.2019.0221

• Research Articles • Previous Articles     Next Articles

Distribution patterns and driving factors of leaf C, N and P stoichiometry of coniferous species on the eastern Qinghai-Xizang Plateau, China

CAI Qin1,2,DING Jun-Xiang1,2,ZHANG Zi-Liang1,HU Jun1,2,WANG Qi-Tong1,2,YIN Ming-Zhen1,2,LIU Qing1,YIN Hua-Jun1,*()   

  1. 1 Chengdu Institute of Biology, Chinese Academy of Sciences, Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization of Chinese Academy of Sciences, and Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province, Chengdu 610041, China
    2 University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2019-09-27 Accepted:2019-12-05 Online:2019-12-20 Published:2020-01-26
  • Contact: YIN Hua-Jun ORCID:0000-0001-9202-8286
  • Supported by:
    Supported by the Second Qinghai-Xizang Plateau Scientific Expedition and Research Program(STEP2019QZKK0301);Frontier Science Key Research Programs of Chinese Academy of Science(QYZDB-SSW-SMC023);National Natural Science Foundation of China(31872700);National Natural Science Foundation of China(31700387);Key Research Programs of Sichuan Province(18ZDYF1821)

Abstract:

Aims The leaf stoichiometry and potential driving factors play a vital role in understanding the distribution patterns of plant community and predicting the plant responses to environmental changes. In this study, we aimed to investigate the spatial distribution patterns and driving factors of leaf carbon (C), nitrogen (N) and phosphorus (P) stoichiometry of coniferous species on the eastern Qinghai-Xizang Plateau, China.
Methods We collected leaf and soil samples from 29 coniferous tree species at 84 sampling sites on the eastern Qinghai-Xizang Plateau. Linear fitting was used to analyze the variation patterns of leaf stoichiometry along geographical and climatic gradients. Partial redundancy analysis was used to characterize the relative contributions of climate and soil factors to leaf stoichiometry variation patterns.
Important findings (1) At the level of family and genus, C and N concentrations as well as C:N of leaves were significantly different across distinct conifer species. The leaf N:P was less than 14, indicating that conifer species in the study region were mainly N-limited. (2) Leaf N and P concentrations showed a consistent distribution pattern along environmental gradients. Specifically, N and P concentrations of leaves were significantly decreased with elevated latitude and altitude, while remarkably increased with the increase of mean annual temperature (MAT) and mean annual precipitation (MAP). In comparison, leaf C concentration had no significant correlation with latitude, altitude, MAT or MAP. (3) The leaf C:N and C:P showed an opposite distribution pattern with leaf N and P concentrations, which significantly increased with elevated latitude and altitude, while markedly declined with the increase of MAT and MAP. Leaf N:P had no significant correlation with altitude, MAT or MAP. (4) The main driving factors of leaf C, N, P concentrations and their stoichiometric characteristics were different. Specifically, soil properties were the main driving factors accounting for the variations of leaf C concentration and N:P. The variations of leaf N and P concentrations as well as ratios of C:N and C:P were primarily explained by climatic factors. Collectively, variations of leaf stoichiometry of coniferous species along environmental gradients in the study region provided a compelling support for the Temperature Biogeochemistry Hypothesis. These findings largely improved the understanding of the distribution patterns and driving mechanism of leaf stoichiometry under changing environments.

Key words: leaf stoichiometry, distribution pattern, driving factor, the eastern Qinghai-Xizang Plateau, subalpine coniferous species