College of Life Science, Sichuan Normal University, Chengdu, China.
College of Ecology and Environment, Chengdu University of Technology, Chengdu, China.
PLoS One. 2022 Dec 2;17(12):e0278656. doi: 10.1371/journal.pone.0278656. eCollection 2022.
Different nutrient supply brings about changes in leaf stoichiometry, which may affect growth rate and primary production of plants. Invasion of alien plants is a severe threat to biodiversity and ecosystem worldwide. A pot experiment was conducted by using three stoloniferous alien plants Wedelia trilobata, Alternanther philoxeroides and Hydrocotyle vulgaris to investigate effects of nutrient supply on their leaf stoichiometry and relative growth rate. Different nitrogen or phosphorus supply was applied in the experiment (N1:1 mmol L-1, N2:4 mmol L-1, and N3:8 mmol L-1, P1:0.15 mmol L-1, P2:0.6 mmol L-1 and P3:1.2 mmol L-1). Nitrogen and phosphorus concentrations in leaves of the three alien plants significantly increased with increase of nitrogen supply. With increase of phosphorus supply, nitrogen or phosphorus concentration of leaf was complex among the three alien plants. N:P ratio in leaf of the three alien plants subjected to different levels of nutrient supply was various. A positive correlation between relative growth rate and N:P ratio of the leaf is observed in W. trilobata and A. philoxeroides suffering from N-limitation. A similar pattern was not observed in Hydrocotyle vulgaris. We tentatively concluded that correlations between relative growth rate and N: P ratio of the leaf could be affected by species as well as nutrient supply. It is suggested that human activities, invasive history, local abundance of species et al maybe play an important role in the invasion of alien plants as well as relative growth rate.
不同的养分供应会导致叶片化学计量比发生变化，从而可能影响植物的生长速度和初级生产力。外来植物的入侵是对全球生物多样性和生态系统的严重威胁。本研究采用盆栽实验，选用三种匍匐型外来植物三裂叶蟛蜞菊、空心莲子草和铜钱草，研究养分供应对外来植物叶片化学计量比和相对生长率的影响。在实验中施加不同氮或磷供应（N1：1 mmol L-1，N2：4 mmol L-1，N3：8 mmol L-1，P1：0.15 mmol L-1，P2：0.6 mmol L-1，P3：1.2 mmol L-1）。随着氮供应的增加，三种外来植物叶片的氮、磷浓度显著增加。随着磷供应的增加，三种外来植物叶片的氮或磷浓度之间的关系较为复杂。不同养分供应水平下，三种外来植物叶片的 N:P 比各不相同。在受到氮限制的三裂叶蟛蜞菊和空心莲子草中，相对生长率与叶片 N:P 比呈正相关。然而，在铜钱草中并没有观察到类似的模式。我们推测，相对生长率与叶片 N:P 比之间的相关性可能受到物种和养分供应的影响。人类活动、入侵历史、当地物种丰度等因素可能在外来植物的入侵以及相对生长率中发挥重要作用。
