Zhang Haonan, Gao Yuanyun, Zheng Xiao, Hu Yaping, Zhou Xu, Fang Yanming, Li Yao, Xie Lei, Ding Hui
Innovative Research Team for Forest Restoration Mechanisms, Chishui National Ecological Quality Comprehensive Monitoring Stations, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment (MEE), Nanjing 210042, China.
Research Center for Nature Conservation and Biodiversity, State Environmental Protection Scientific Observation and Research Station for Ecology and Environment of Wuyi Mountains, State Environmental Protection Key Laboratory on Biosafety, Nanjing Institute of Environmental Sciences, Ministry of Ecology and Environment (MEE), Nanjing 210042, China.
Plants (Basel). 2024 Jul 21;13(14):1994. doi: 10.3390/plants13141994.
Understanding the biodiversity-productivity relationship (BPR) is crucial for biodiversity conservation and ecosystem management. While it is known that diversity enhances forest productivity, the underlying mechanisms at the local neighborhood level remain poorly understood. We established a 9.6 ha dynamic forest plot to study how neighborhood diversity, intraspecific competition, and interspecific competition influence tree growth across spatial scales using linear mixed-effects models. Our analysis reveals a significant positive correlation between neighborhood species richness (NSR) and relative growth rate (RGR). Notably, intraspecific competition, measured by conspecific neighborhood density and resource competition, negatively impacts RGR at finer scales, indicating intense competition among conspecifics for limited resources. In contrast, interspecific competition, measured by heterospecific density and resource competition, has a negligible impact on RGR. The relative importance of diversity and intra/interspecific competition in influencing tree growth varies with scale. At fine scales, intraspecific competition dominates negatively, while at larger scales, the positive effect of NSR on RGR increases, contributing to a positive BPR. These findings highlight the intricate interplay between local interactions and spatial scale in modulating tree growth, emphasizing the importance of considering biotic interactions and spatial variability in studying BPR.
理解生物多样性与生产力的关系（BPR）对于生物多样性保护和生态系统管理至关重要。虽然已知多样性可提高森林生产力，但在局部邻域水平上的潜在机制仍知之甚少。我们建立了一个9.6公顷的动态森林样地，使用线性混合效应模型研究邻域多样性、种内竞争和种间竞争如何在空间尺度上影响树木生长。我们的分析揭示了邻域物种丰富度（NSR）与相对生长率（RGR）之间存在显著的正相关。值得注意的是，以同种邻域密度和资源竞争衡量的种内竞争，在更精细的尺度上对RGR产生负面影响，表明同种个体之间为有限资源进行激烈竞争。相比之下，以异种密度和资源竞争衡量的种间竞争对RGR的影响可忽略不计。多样性和种内/种间竞争对树木生长影响的相对重要性随尺度而变化。在精细尺度上，种内竞争起主导的负面影响，而在较大尺度上，NSR对RGR的积极影响增加，促成了积极的BPR。这些发现突出了局部相互作用和空间尺度在调节树木生长中的复杂相互作用，强调了在研究BPR时考虑生物相互作用和空间变异性的重要性。
