Department of Entomology, University of Maryland, College Park, MD 20742, USA.
Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504, USA.
Philos Trans R Soc Lond B Biol Sci. 2023 Jul 17;378(1881):20220186. doi: 10.1098/rstb.2022.0186. Epub 2023 May 29.
Motivated by accelerating anthropogenic extinctions, decades of biodiversity-ecosystem function (BEF) experiments show that ecosystem function declines with species loss from local communities. Yet, at the local scale, changes in species' total and relative abundances are more common than species loss. The consensus best biodiversity measures are Hill numbers, which use a scaling parameter, , to emphasize rarer versus more common species. Shifting that emphasis captures distinct, function-relevant biodiversity gradients beyond species richness. Here, we hypothesized that Hill numbers that emphasize rare species more than richness does may distinguish large, complex and presumably higher-functioning assemblages from smaller and simpler ones. In this study, we tested which values of produce the strongest BEF relationships in community datasets of ecosystem functions provided by wild, free-living organisms. We found that values that emphasized rare species more than richness does most often correlated most strongly with ecosystem functions. As emphasis shifted to more common species, BEF correlations were often weak and/or negative. We argue that unconventional Hill diversities that shift emphasis towards rarer species may be useful for describing biodiversity change, and that employing a wide spectrum of Hill numbers can clarify mechanisms underlying BEF relationships. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.
受加速的人为物种灭绝的驱动，数十年来的生物多样性-生态系统功能（BEF）实验表明，生态系统功能随着本地群落中物种的丧失而下降。然而，在局部尺度上，物种的总丰度和相对丰度的变化比物种丧失更为常见。共识的最佳生物多样性指标是希尔数，它使用一个标度参数 ，来强调更稀有而非更常见的物种。改变这种强调可以捕捉到独特的、与功能相关的生物多样性梯度，超越物种丰富度。在这里，我们假设强调稀有物种而不是丰富度的希尔数可能会将大型、复杂且功能较高的组合与较小和较简单的组合区分开来。在这项研究中，我们测试了在由野生、自由生活的生物提供的生态系统功能的群落数据集，哪些 值会产生最强的 BEF 关系。我们发现，强调稀有物种而不是丰富度的 值最常与生态系统功能强烈相关。随着对更常见物种的强调，BEF 相关性往往较弱和/或为负。我们认为，将重点转移到更稀有的物种上的非常规希尔多样性可能有助于描述生物多样性变化，并且采用广泛的希尔数可以阐明 BEF 关系的机制。本文是主题为“检测和归因生物多样性变化的原因：需求、差距和解决方案”的一部分。
