Leaf Stoichiometry of Potentilla fruticosa Across Elevations in China's Qilian Mountains

Yanyan Qin; Wei Liu; Xiaofang Zhang; Jan F Adamowski; Asim Biswas

doi:10.3389/fpls.2022.814059

Leaf Stoichiometry of Potentilla fruticosa Across Elevations in China's Qilian Mountains

Front Plant Sci. 2022 Feb 24:13:814059. doi: 10.3389/fpls.2022.814059. eCollection 2022.

Authors

Yanyan Qin^{1

2

3}, Wei Liu^{2

3}, Xiaofang Zhang², Jan F Adamowski⁴, Asim Biswas⁵

Affiliations

¹ Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China.
² Key Laboratory of Ecohydrology of Inland River Basin, Northwest Institution of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China.
³ Qilian Mountains Eco-environment Research Center in Gansu Province, Lanzhou, China.
⁴ Department of Bioresource Engineering, Faculty of Agricultural and Environmental Sciences, McGill University, Sainte-Anne-de-Bellevue, QC, Canada.
⁵ School of Environmental Sciences, University of Guelph, Guelph, ON, Canada.

Abstract

As an individual plant species can develop its own leaf stoichiometry to adapt to environmental changes, this stoichiometry can provide critical information about a plant species' growth and its potential management in the ecosystem housing it. However, leaf stoichiometry is largely undocumented in regions with large environmental changes arising from differences in elevation. The leaf stoichiometry of Potentilla fruticosa L., a major alpine shrub playing an important role in supporting ecosystem functions and services in China's Qilian Mountains (Northeast Qinghai-Tibetan Plateau), was investigated at different elevations (2,400, 2,600, 2,800, 3,000, 3,200, 3,500, and 3,800 m). At each elevation, leaf elemental (C, N, and P) concentrations were measured in P. fruticosa leaves sampled from three plots (10 × 10 m), and edaphic properties were assessed in nine quadrats (1 × 1 m, three quadrats per plot). Temperature and precipitation were calculated using an empirical formula. Maximum and minimum leaf carbon (C) concentrations ([C] _leaf ) of 524 ± 5.88 and 403 ± 3.01 g kg^-1 were measured at 2,600 and 3,500 m, respectively. Leaf nitrogen (N) concentration ([N] _leaf ) showed a generally increasing trend with elevation and peaked at 3,500 m (27.33 ± 0.26 g kg^-1). Leaf phosphorus (P) concentration ([P] _leaf ) varied slightly from 2,400 to 3,200 m and then dropped to a minimum (0.60 ± 0.10 g kg^-1) at 3800 m. The [C] _leaf :[N] _leaf , [C] _leaf :[P] _leaf , and [N] _leaf :[P] _leaf varied little from 2,400 to 3,000 m but fluctuated somewhat at higher elevations. The main factors affecting P. fruticosa leaf stoichiometry were soil organic C, pH, and soil total P, and the main limiting element for the growth of P. fruticosa in the study area was P. In conclusion, changes in elevation affected leaf stoichiometry of P. fruticosa mainly due to altered soil properties, and addressing phosphorus limitation, especially at higher elevations mainly due to losses caused by high precipitation and sparse vegetation, is a key measure to promote P. fruticosa growth in this region.

Keywords: Mountainous regions; Potentilla; plant adaptation; plant growth; plant traits.