Linking human impacts to community processes in terrestrial and freshwater ecosystems

• Published in: Ecology letters Vol. 26; no. 2; pp. 203 - 218
• Main Authors: McFadden, Ian R., Sendek, Agnieszka, Brosse, Morgane, Bach, Peter M., Baity‐Jesi, Marco, Bolliger, Janine, Bollmann, Kurt, Brockerhoff, Eckehard G., Donati, Giulia, Gebert, Friederike, Ghosh, Shyamolina, Ho, Hsi‐Cheng, Khaliq, Imran, Lever, J. Jelle, Logar, Ivana, Moor, Helen, Odermatt, Daniel, Pellissier, Loïc, Queiroz, Luiz Jardim, Rixen, Christian, Schuwirth, Nele, Shipley, J. Ryan, Twining, Cornelia W., Vitasse, Yann, Vorburger, Christoph, Wong, Mark K. L., Zimmermann, Niklaus E., Seehausen, Ole, Gossner, Martin M., Matthews, Blake, Graham, Catherine H., Altermatt, Florian, Narwani, Anita
• Format: Journal Article
• Language: English
• Published: England Blackwell Publishing Ltd 01-02-2023; John Wiley and Sons Inc
• Subjects: Anthropogenic Effects; aquatic ecology; Aquatic ecosystems; Biodiversity; Biological Evolution; Climate Change; Dispersal; Divergence; drift; Ecosystem; Ecosystems; Environmental changes; Fresh Water; Freshwater ecosystems; global change; Habitat loss; Human influences; Humans; mechanism; selection; Speciation; synthesis; synthesis; aquatic ecology; selection; global change; dispersal; mechanism; drift; speciation
• ISSN: 1461-023X; 1461-0248; 1461-0248
• DOI: 10.1111/ele.14153

Human impacts such as habitat loss, climate change and biological invasions are radically altering biodiversity, with greater effects projected into the future. Evidence suggests human impacts may differ substantially between terrestrial and freshwater ecosystems, but the reasons for these differences are poorly understood. We propose an integrative approach to explain these differences by linking impacts to four fundamental processes that structure communities: dispersal, speciation, species‐level selection and ecological drift. Our goal is to provide process‐based insights into why human impacts, and responses to impacts, may differ across ecosystem types using a mechanistic, eco‐evolutionary comparative framework. To enable these insights, we review and synthesise (i) how the four processes influence diversity and dynamics in terrestrial versus freshwater communities, specifically whether the relative importance of each process differs among ecosystems, and (ii) the pathways by which human impacts can produce divergent responses across ecosystems, due to differences in the strength of processes among ecosystems we identify. Finally, we highlight research gaps and next steps, and discuss how this approach can provide new insights for conservation. By focusing on the processes that shape diversity in communities, we aim to mechanistically link human impacts to ongoing and future changes in ecosystems.
Community‐level responses to human impacts can differ substantially between terrestrial and freshwater ecosystems. We propose an integrative approach to explain divergent community responses by linking human impacts to the fundamental processes structuring communities (sensu Vellend, 2016): dispersal, speciation, species‐level selection and ecological drift. Using our approach combined with a literature review, we provide mechanistic insights into why responses to human impacts may differ across ecosystems and suggest ways forward to make predictions about future impacts.