Department of Zoology, University of British Columbia, Vancouver, V6T 1Z4 British Columbia, Canada.
Hakai Institute, Heriot Bay, V0P 1H0 British Columbia, Canada.
Philos Trans R Soc Lond B Biol Sci. 2023 Jul 17;378(1881):20220187. doi: 10.1098/rstb.2022.0187. Epub 2023 May 29.
Species richness is an essential biodiversity variable indicative of ecosystem states and rates of invasion, speciation and extinction both contemporarily and in fossil records. However, limited sampling effort and spatial aggregation of organisms mean that biodiversity surveys rarely observe every species in the survey area. Here we present a non-parametric, asymptotic and bias-minimized richness estimator, by modelling how spatial abundance characteristics affect observation of species richness. Improved asymptotic estimators are critical when both absolute richness and difference detection are important. We conduct simulation tests and applied to a tree census and a seaweed survey. consistently outperforms other estimators in balancing bias, precision and difference detection accuracy. However, small difference detection is poor with any asymptotic estimator. An R-package, , performs the proposed richness estimations along with other asymptotic estimators and bootstrapped precisions. Our results explain how natural and observer-induced variations affect species observation, how these factors can be used to correct observed richness using the estimator on a variety of data, and why further improvements are critical for biodiversity assessments. This article is part of the theme issue 'Detecting and attributing the causes of biodiversity change: needs, gaps and solutions'.
物种丰富度是一个基本的生物多样性变量，它可以指示生态系统的状态，以及当代和化石记录中入侵、物种形成和灭绝的速度。然而，由于采样工作的局限性和生物的空间聚集，生物多样性调查很少能观察到调查区域中的每一个物种。在这里，我们提出了一种非参数、渐近和偏最小化的丰富度估计器，通过模拟空间丰度特征如何影响物种丰富度的观察来实现。当绝对丰富度和差异检测都很重要时，改进的渐近估计器是至关重要的。我们进行了模拟测试，并将其应用于树木普查和海藻调查。结果表明，在平衡偏差、精度和差异检测准确性方面， 始终优于其他估计器。然而，任何渐近估计器的小差异检测都很差。一个名为 的 R 包，可以执行所提出的丰富度估计，以及其他渐近估计器和引导精度。我们的结果解释了自然和观察者引起的变化如何影响物种的观察，以及如何利用这些因素使用 估计器来纠正各种数据中的观察到的丰富度，以及为什么进一步的改进对生物多样性评估至关重要。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。
