School of Geographical Sciences, Fujian Normal University/Cultivation Base of State Key Laboratory of Humid Subtropical Mountain Ecology, Fuzhou 350007, China.
Sanming Forest Ecosystem and Global Change National Observation and Research Station of Fujian Province, Sanming 365000, Fujian, China.
Ying Yong Sheng Tai Xue Bao. 2023 May;34(5):1153-1160. doi: 10.13287/j.1001-9332.202305.005.
To understand leaf litter stoichiometry in a subtropical evergreen broadleaved forest, we measured the contents of carbon (C), nitrogen (N) and phosphorus (P) in leaf litters of 62 main woody species in a natural forest of Nature Reserve in Sanming, Fujian Province. Differences in leaf litter stoichiometry were analyzed across leaf forms (evergreen, deciduous), life forms (tree, semi-tree or shrub), and main families. Additionally, the phylogenetic signal was measured by Blomberg's to explore the correlation between family level differentiation time and litter stoichiometry. Our results showed that the contents of C, N and P in the litter of 62 woody species were 405.97-512.16, 4.45-27.11, and 0.21-2.53 g·kg, respectively. C/N, C/P and N/P were 18.6-106.2, 195.9-2146.8, and 3.5-68.9, respectively. Leaf litter P content of evergreen tree species was significantly lower than that of deciduous tree species, and C/P and N/P of evergreen tree species were significantly higher than those of deciduous tree species. There was no significant difference in C, N content and C/N between the two leaf forms. There was no significant difference in litter stoichiometry among trees, semi-trees and shrubs. Effects of phylogeny on C, N content and C/N in leaf litter was significant, but not on P content, C/P and N/P. Family differentiation time was negatively correlated with leaf litter N content, and positively correlated with C/N. Leaf litter of Fagaceae had high C and N contents, C/P and N/P, and low P content and C/N, with an opposite trend for Sapidaceae. Our findings indicated that litter in subtropical forest had high C, N content and N/P, but low P content, C/N, and C/P, compared with the global scale average value. Litter of tree species in older sequence of evolutionary development had lower N content but higher C/N. There was no difference of leaf litter stoichiometry among life forms. There were significant differences in P content, C/P, and N/P between different leaf forms, with a characteristic of convergence.
为了了解亚热带常绿阔叶林的凋落物化学计量特征，我们测量了福建省三明市自然保护区天然林 62 种主要木本植物凋落物中碳（C）、氮（N）和磷（P）的含量。通过分析不同叶型（常绿、落叶）、生活型（乔木、半乔木或灌木）和主要科属的凋落物化学计量差异，探讨了凋落物化学计量在不同叶型和生活型之间的差异。此外，我们还通过 Blomberg 的方法测量了系统发育信号，以探讨科属分化时间与凋落物化学计量之间的相关性。结果表明，62 种木本植物凋落物的 C、N 和 P 含量分别为 405.97-512.16、4.45-27.11 和 0.21-2.53 g·kg-1，C/N、C/P 和 N/P 分别为 18.6-106.2、195.9-2146.8 和 3.5-68.9。常绿树种凋落物 P 含量显著低于落叶树种，C/P 和 N/P 显著高于落叶树种。两种叶型之间的 C、N 含量和 C/N 无显著差异。乔木、半乔木和灌木的凋落物化学计量无显著差异。系统发育对凋落物 C、N 含量和 C/N 的影响显著，但对 P 含量、C/P 和 N/P 没有影响。科属分化时间与凋落物 N 含量呈正相关，与 C/N 呈负相关。壳斗科凋落物具有较高的 C、N 含量和 C/P、N/P，较低的 P 含量和 C/N，与 Sapindaceae 相反。研究结果表明，与全球平均水平相比，亚热带森林凋落物具有较高的 C、N 含量和 N/P，但 P 含量、C/N 和 C/P 较低。在进化发育序列较老的树种中，凋落物的 N 含量较低，但 C/N 较高。不同生活型之间的凋落物化学计量无差异。不同叶型之间的 P 含量、C/P 和 N/P 存在显著差异，具有趋同的特征。
