Fan Ruirui, Sun Jun, Yang Fuchun, Li Man, Zheng Yuan, Zhong Quanlin, Cheng Dongliang
Fujian Provincial Key Laboratory of Plant Ecophysiology Fujian Normal University Fuzhou Fujian China.
Key Laboratory of Humid Subtropical Eco-geographical Process Ministry of Education Fuzhou Fujian China.
Ecol Evol. 2017 Sep 18;7(21):8761-8769. doi: 10.1002/ece3.3419. eCollection 2017 Nov.
Empirical studies indicate that the exponents governing the scaling of plant respiration rates () with respect to biomass () numerically vary between three-fourth for adult plants and 1.0 for seedlings and saplings and are affected by nitrogen (N) and phosphorus (P) content. However, whether the scaling of with respect to (or N and P) varies among different phylogenetic groups (e.g., gymnosperms vs. angiosperms) or during the growing and dormant seasons remains unclear. We measured the whole-plant and , and N and P content of the seedlings of four woody species during the growing season (early October) and the dormant season (January). The data show that (i) the scaling exponents of versus , versus N, and versus P differed significantly among the four species, but (ii), not between the growing and dormant seasons for each of the four species, although (iii) the normalization constants governing the scaling relationships were numerically greater for the growing season compared to the dormant season. In addition, (iv) the scaling exponents of versus , versus N, and versus P were numerically larger for the two angiosperm species compared to those of the two gymnosperm species, (v) the interspecific scaling exponents for the four species were greater during the growing season than in the dormant season, and (vi), interspecifically, P scaled nearly isometric with N content. Those findings indicate that the metabolic scaling relationships among , , N, and P manifest seasonal variation and differ between angiosperm and gymnosperm species, that is, there is no single, canonical scaling exponent for the seedlings of woody species.
实证研究表明，支配植物呼吸速率（）相对于生物量（）的缩放指数在数值上因成年植物的四分之三到幼苗和幼树的1.0而异，并且受氮（N）和磷（P）含量的影响。然而，相对于（或N和P）的缩放是否在不同的系统发育类群（例如裸子植物与被子植物）之间或在生长和休眠季节期间有所不同仍不清楚。我们在生长季节（10月初）和休眠季节（1月）测量了四种木本植物幼苗的全株和、N和P含量。数据表明：（i）四种物种之间相对于、相对于N和相对于P的缩放指数存在显著差异，但（ii）对于四种物种中的每一种，生长和休眠季节之间没有差异，尽管（iii）与休眠季节相比，生长季节中支配缩放关系的归一化常数在数值上更大。此外，（iv）与两种裸子植物物种相比，两种被子植物物种相对于、相对于N和相对于P的缩放指数在数值上更大，（v）四种物种的种间缩放指数在生长季节比休眠季节更大，并且（vi）种间而言，P与N含量几乎呈等比缩放。这些发现表明，、、N和P之间的代谢缩放关系表现出季节变化，并且在被子植物和裸子植物物种之间存在差异，也就是说，木本植物幼苗没有单一的、标准的缩放指数。
