Ecological stoichiometric characteristics and influencing factors of carbon, nitrogen, and phosphorus in the leaves of Sophora alopecuroides L. in the Yili River Valley, Xinjiang

Yulu Zhang; Dong Cui; Yuhai Yang; Haijun Liu; Haijun Yang; Yang Zhao

doi:10.7717/peerj.11701

Ecological stoichiometric characteristics and influencing factors of carbon, nitrogen, and phosphorus in the leaves of Sophora alopecuroides L. in the Yili River Valley, Xinjiang

PeerJ. 2021 Jul 14:9:e11701. doi: 10.7717/peerj.11701. eCollection 2021.

Authors

Yulu Zhang^{1

2}, Dong Cui^{1

2

3}, Yuhai Yang³, Haijun Liu^{1

2}, Haijun Yang^{1

2

4}, Yang Zhao^{1

2}

Affiliations

¹ College of Biology and Geography Sciences, Yili Normal University, Yining City, Yili Kazak Autonomous Prefecture, China.
² Institute of Resources and Ecology, Yili Normal University, Yining City, Yili Kazak Autonomous Prefecture, China.
³ State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
⁴ Ministry of Education Key Laboratory of Vegetation Ecology, Institute of Grassland Science, Northeast Normal University, Changchun, China.

Abstract

Background: Sophora alopecuroides L. (S. alopecuroides L.) is a perennial herb widely distributed throughout Xinjiang, China. It is characterized by its rapid diffusion ability.

Methods: To reveal the ecological mechanism of the rapid spread of S. alopecuroides, and to elucidate the ecological stoichiometric characteristics of C, N, and P (and the influencing factors) in the leaves of S. alopecuroides, leaves were sampled from four habitats-forest, roadside, farmland, and desert-across the Yili River Valley. The variation rules of the ecological stoichiometric characteristics of C, N, and P in the leaves of S. alopecuroides were analyzed. Correlations between the ecological stoichiometric characteristics of leaves and environmental factors were examined using redundancy analysis (RDA).

Results: (1) The C, N, and P contents of S. alopecuroides leaves were 391.30-533.10 g/kg, 8.90-43.14 g/kg, and 0.71-2.04 g/kg, respectively, and the C/N, C/P, and N/P ratios were 10.34-4.94, 209.05-698.73, and 10.78-31.43 respectively. (2) The C content and C/P ratio of S. alopecuroides leaves were the highest in the desert habitat, leaf N content and N/P ratio were the highest in the forest habitat, leaf P content was the highest in the farmland habitat, and the leaf C/N ratio was the highest in the roadside habitat. (3) RDA showed that available potassium (AK) and pH were the main factors affecting the ecological stoichiometric characteristics of S. alopecuroides leaves in Yili Valley (p ≤ 0.05), and these factors were positively correlated with C, N, P, and N/P, and negatively correlated with C/P and C/N. AK was the dominant factor that affected the P content of S. alopecuroides leaves, and appropriate reduction of K fertilizer would be conducive to restraining the spread of S. alopecuroides. Soil C, N, P, and K content, soil organic matter (OM), nitrate nitrogen (NO₃ ^--N), ammonium nitrogen (NH₄ ⁺-N), and AK had no significant effect on the ecological stoichiometric characteristics of leaves (p > 0.05).

Keywords: Ecological stoichiometry characteristics; Redundancy analysis; S. alopecuroides L.; Soil physical-chemical factors.

Grants and funding

This study was supported by the Opening Fund of The State Key Laboratory of Desert and Oasis Ecology (Fund number: G2020-02-02) and the Tianshan Youth Program, a special talent program in Xinjiang Uygur Autonomous Region (Fund number: 2018Q076). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.