Yao Jie, Huang Jihong, Zang Runguo
Ecology and Nature Conservation Institute, Chinese Academy of Forestry Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Beijing China.
Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry University Nanjing China.
Ecol Evol. 2023 Aug 31;13(9):e10487. doi: 10.1002/ece3.10487. eCollection 2023 Sep.
Changes in biodiversity often affect ecosystem functioning. However, most previous biodiversity and ecosystem functioning (BEF) studies have generally been limited to very small spatial grains. Thus, knowledge regarding the biodiversity-ecosystem functioning relationships across spatial scales is lacking. Moreover, the multiscale nature of biodiversity, and specifically β diversity (i.e., spatial heterogeneity in species composition) was still largely missing in BEF studies. Here, using the vegetation and functional trait data collected from four 6-ha forest dynamics plots (FDPs) in temperate and tropical forests in China, we examine the scale-dependent relationships between tree diversity and the aboveground biomass (AGB), as well as the roles of species spatial heterogeneity in determining the AGB. In tropical forests, the effect of species richness on AGB decreased with spatial grains, while functional dominance played a stronger role at larger spatial grains. In temperate forests, positive relationship between diversity and AGB occurred at all spatial grains, especially on smaller scales. In both temperate and tropical forests, β diversity was positively correlated with AGB, but weaker than α diversity in determining AGB. Overall, complementarity and selection hypothesis play dominant role in determining AGB in temperate and tropical forests, respectively. The roles of these underlying mechanisms are more pronounced with increasing spatial scales. β diversity, a hitherto underexplored facet of biodiversity, is likely to increase ecosystem functions by species spatial turnover and should not be neglected in BEF explorations. Our findings have practical implications for forest management and demonstrate that biotic heterogeneity plays an important positive role in ecosystem functioning.
生物多样性的变化通常会影响生态系统功能。然而，以往大多数生物多样性与生态系统功能（BEF）研究一般都局限于非常小的空间粒度。因此，缺乏关于跨空间尺度的生物多样性与生态系统功能关系的知识。此外，生物多样性的多尺度性质，特别是β多样性（即物种组成的空间异质性）在BEF研究中仍基本缺失。在此，利用在中国温带和热带森林的四个6公顷森林动态样地（FDPs）收集的植被和功能性状数据，我们研究了树木多样性与地上生物量（AGB）之间的尺度依赖关系，以及物种空间异质性在决定AGB中的作用。在热带森林中，物种丰富度对AGB的影响随空间粒度减小，而功能优势在较大空间粒度上发挥更强作用。在温带森林中，多样性与AGB之间在所有空间粒度上均呈正相关，尤其是在较小尺度上。在温带和热带森林中，β多样性均与AGB呈正相关，但在决定AGB方面比α多样性弱。总体而言，互补性和选择假说分别在决定温带和热带森林的AGB中起主导作用。这些潜在机制的作用随着空间尺度的增加而更加明显。β多样性是生物多样性一个迄今未充分探索的方面，可能通过物种空间周转增加生态系统功能，在BEF探索中不应被忽视。我们的研究结果对森林管理具有实际意义，并表明生物异质性在生态系统功能中发挥着重要的积极作用。
