Ding Dongdong, Arif Muhammad, Liu Minghui, Li Jiajia, Hu Xin, Geng Qianwen, Yin Fan, Li Changxiao
Key Laboratory of Eco-Environments in the Three Gorges Reservoir Region (Ministry of Education), Chongqing Key Laboratory of Plant Resource Conservation and Germplasm Innovation, College of Life Sciences, Southwest University, Chongqing, China.
Biological Science Research Center, Academy for Advanced Interdisciplinary Studies, Southwest University, Chongqing, China.
Front Plant Sci. 2022 Aug 1;13:979023. doi: 10.3389/fpls.2022.979023. eCollection 2022.
Carbon (C), nitrogen (N), and phosphorus (P) stoichiometric ratios give valuable insight into ecosystem function. The purpose of the present study is to probe into the C, N, and P stoichiometric characteristics in various organs and their relationships with soil factors of the dominant deciduous conifer plant species ( and ) during afforestation in the riparian zone of Three Gorges Reservoir. The results showed only a small change in the concentration of C in different plant organs and soils. contained mean N and P concentrations of 7.63 and 1.54 g/kg in fine roots, 5.10 and 0.56 g/kg in stems, and 15.48 and 2.30 g/kg in leaves, respectively. Whereas had a mean N and P concentration of 7.08 and 1.37 g/kg in fine roots, 4.84 and 0.59 g/kg in stems, and 16.89 and 2.23 g/kg in leaves. The N:P ratios in all organs were below 14, indicating that N may have inhibited tree growth. The fine roots P and N:P of were weak plasticity and weak homeostasis, and those of were plasticity and weak plasticity. Their stems and leaves adhere to strict homeostasis. N concentrations were significantly positively related to P concentrations in every tissue (except the stems of ), and C concentrations were significantly positively associated with P concentrations in the stems and leaves of and ( < 0.05). Likewise, soil P and fine root P were positively associated ( < 0.01). This study contributes to the understanding of deciduous conifer plant stoichiometry. It demonstrates N, P, and N:P stoichiometric homeostasis in and , which can withstand flooding and are suitable for vegetation restoration in the hydro-fluctuation zone.
碳（C）、氮（N）和磷（P）化学计量比为深入了解生态系统功能提供了有价值的信息。本研究的目的是探究三峡水库消落带造林过程中优势落叶针叶树种（和）各器官的C、N、P化学计量特征及其与土壤因子的关系。结果表明，不同植物器官和土壤中的C浓度变化较小。在细根中的平均N和P浓度分别为7.63和1.54 g/kg，茎中的为5.10和0.56 g/kg，叶中的为15.48和2.30 g/kg。而在细根中的平均N和P浓度分别为7.08和1.37 g/kg，茎中的为4.84和0.59 g/kg，叶中的为16.89和2.23 g/kg。所有器官中的N:P比均低于14，表明N可能抑制了树木生长。的细根P和N:P具有较弱的可塑性和较弱的内稳态，而的细根P和N:P具有可塑性和较弱的可塑性。它们的茎和叶保持严格的内稳态。每个组织中的N浓度与P浓度均呈显著正相关（的茎除外），的茎和叶以及的茎和叶中的C浓度与P浓度均呈显著正相关（P<0.05）。同样，土壤P与细根P呈正相关（P<0.01）。本研究有助于理解落叶针叶植物的化学计量学。它揭示了和的N、P以及N:P化学计量内稳态，这两种植物能够耐受水淹，适合在消落带进行植被恢复。
