Yang Zhichun, Luo Ying, Ye Nan, Yang Lishunan, Yin Qiulong, Jia Shihong, He Chunmei, Yuan Zuoqiang, Hao Zhanqing, Ali Arshad
School of Ecology and Environment Northwestern Polytechnical University Shaanxi China.
CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology Chinese Academy of Sciences Liaoning China.
Ecol Evol. 2022 Sep 11;12(9):e9275. doi: 10.1002/ece3.9275. eCollection 2022 Sep.
Congeneric species are critical for understanding the underlying ecological mechanisms of biodiversity maintenance. Ecological mechanisms such as conspecific negative density dependence, species differences in life-history stages related to habitat preference, and limiting similarity are known to influence plant fitness, thereby influencing species coexistence and biodiversity. However, our understanding of these phenomena as they apply to coexistence among coniferous species is limited. We studied two congeneric species, (PA) and (PT), both of which are common pioneer species typically succeeded by oaks (), in a 25-ha warm temperate deciduous broad-leaved forest. Here, we addressed the following questions: (1) How do population structures and distributions patterns of these two species vary with respect to different life-history stages? (2) Does intra- and interspecific competition vary with respect to three life-history stages? And (3) What are the relative contributions of topographic and soil variables to the spatial distributions of the species across the three life-history stages? In addressing these questions, we utilized the pair-correlation function g(r), redundancy analysis (RDA), variance partitioning (VP), and hierarchical partitioning (HP) to identify habitat preferences and conspecific negative density dependence at different life-history stages from small to large trees. The results revealed that in both species, individuals in different life-history stages were subject to significant habitat heterogeneity, with a tendency for small trees to be distributed at higher latitudes that may be represents climate-change-driven migration in both species. In addition, the effects of conspecific negative density dependence on PT were stronger than those on PA due to limited dispersal in PT. Furthermore, we found that interspecific competition was weak due to the species differences in resource utilization and preference for key habitats. Our study shows that congeneric species avoids competition by exploiting distinct habitats and provides insight into forest community structure.
同属物种对于理解生物多样性维持的潜在生态机制至关重要。诸如同种负密度依赖、与栖息地偏好相关的生活史阶段的物种差异以及限制相似性等生态机制已知会影响植物适合度，从而影响物种共存和生物多样性。然而，我们对于这些现象在针叶树种共存中的应用的理解是有限的。我们在一片25公顷的暖温带落叶阔叶林里研究了两个同属物种，即（PA）和（PT），这两个物种都是常见的先锋物种，通常会被橡树（）所取代。在此，我们探讨了以下问题：（1）这两个物种的种群结构和分布模式在不同生活史阶段是如何变化的？（2）种内和种间竞争在三个生活史阶段是否有所不同？以及（3）地形和土壤变量对这两个物种在三个生活史阶段的空间分布的相对贡献是什么？在解决这些问题时，我们利用配对相关函数g(r)、冗余分析（RDA）、方差分解（VP）和层次分解（HP）来从小树到大树识别不同生活史阶段的栖息地偏好和同种负密度依赖。结果表明，在这两个物种中，不同生活史阶段的个体都面临显著的栖息地异质性，小树有分布在较高纬度的趋势，这可能代表了两个物种受气候变化驱动的迁移。此外，由于PT的扩散受限，同种负密度依赖对PT的影响比对PA的影响更强。此外，我们发现由于资源利用和对关键栖息地的偏好存在物种差异，种间竞争较弱。我们的研究表明，同属物种通过利用不同的栖息地来避免竞争，并为森林群落结构提供了见解。
