Department of Natural Resource Management, South Dakota State University, Rapid City, SD 57703.
Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX 77843.
Proc Natl Acad Sci U S A. 2023 Feb 14;120(7):e2201947120. doi: 10.1073/pnas.2201947120. Epub 2023 Feb 6.
We are in a modern biodiversity crisis that will restructure community compositions and ecological functions globally. Large mammals, important contributors to ecosystem function, have been affected directly by purposeful extermination and indirectly by climate and land-use changes, yet functional turnover is rarely assessed on a global scale using metrics based on functional traits. Using ecometrics, the study of functional trait distributions and functional turnover, we examine the relationship between vegetation cover and locomotor traits for artiodactyl and carnivoran communities. We show that the ability to detect a functional relationship is strengthened when locomotor traits of both primary consumers (artiodactyls, n = 157 species) and secondary consumers (carnivorans, n = 138 species) are combined into one trophically integrated ecometric model. Overall, locomotor traits of 81% of communities accurately estimate vegetation cover, establishing the advantage of trophically integrated ecometric models over single-group models (58 to 65% correct). We develop an innovative approach within the ecometrics framework, using ecometric anomalies to evaluate mismatches in model estimates and observed values and provide more nuance for understanding relationships between functional traits and vegetation cover. We apply our integrated model to five paleontological sites to illustrate mismatches in the past and today and to demonstrate the utility of the model for paleovegetation interpretations. Observed changes in community traits and their associated vegetations across space and over time demonstrate the strong, rapid effect of environmental filtering on community traits. Ultimately, our trophically integrated ecometric model captures the cascading interactions between taxa, traits, and changing environments.
我们正处在一场现代生物多样性危机之中，这场危机将在全球范围内重组群落组成和生态功能。大型哺乳动物是生态系统功能的重要贡献者，它们直接受到有目的的灭绝以及气候和土地利用变化的间接影响，但功能替代在全球范围内很少使用基于功能特征的指标进行评估。本研究使用生态计量学，即功能特征分布和功能替代的研究，来检验食草动物和食肉动物群落的植被覆盖与运动特征之间的关系。我们表明，当将初级消费者（偶蹄目动物，n=157 种）和次级消费者（食肉目动物，n=138 种）的运动特征结合到一个营养整合的生态计量模型中时，检测功能关系的能力会得到增强。总体而言，81%的群落的运动特征能够准确估计植被覆盖，这确立了营养整合生态计量模型相对于单一群体模型（正确的为 58%至 65%）的优势。我们在生态计量学框架内开发了一种创新方法，使用生态计量异常来评估模型估计值与观察值之间的不匹配，并为理解功能特征与植被覆盖之间的关系提供更多的细微差别。我们将我们的整合模型应用于五个古生物学地点，以说明过去和今天的模型估计值与观察值之间的不匹配，并展示该模型在古植被解释方面的实用性。跨空间和时间观察到的群落特征及其相关植被的变化表明，环境过滤对群落特征具有强烈而快速的影响。最终，我们的营养整合生态计量模型捕捉了分类群、特征和不断变化的环境之间的级联相互作用。
