Metacommunity Theory and Metabarcoding Reveal the Environmental, Spatial and Biotic Drivers of Meiofaunal Communities in Sandy Beaches

Molecular Ecology, vol. 34, pp. e17733

Abstract

Understanding the processes that shape community assembly is a critical focus of ecology. Marine benthic meiofauna, microscopic invertebrates inhabiting sediment environments, play important roles in ecosystem functioning but have been largely overlooked in metacommunity studies due to the lack of community data. In this study, we quantify the relative contributions of environmental filtering, spatial processes, and biotic associations in structuring meiofaunal communities. We applied Generalised Dissimilarity Modelling (GDM) and Joint Species Distribution Modelling (JSDM) to an extensive metabarcoding dataset comprising 550 samples collected from sandy beaches along over 650 km of the Dutch and German North Sea coast. Our findings reveal that biotic associations, followed by environmental factors, particularly the distance from the low tide line and sediment grain size, are primary drivers of meiofauna community turnover, highlighting the influence of sharp environmental gradients. Spatial factors indicating dispersal limitations have no major impact on community composition, supporting the assumption that microscopic organisms have strong dispersal capabilities. JSDM results demonstrate that while species sorting is a key driver of community assembly, environmental factors are most important in environmentally distinct ('extreme') sites, whereas biotic associations significantly shape community assembly in both environmentally similar and dissimilar habitats, emphasising the need to incorporate species interactions into models of community assembly. By providing insights into the drivers of meiofaunal community structure, our study highlights the importance of environmental gradients and biotic associations in shaping biodiversity patterns and underscores the potential for similar approaches to enhance understanding of other ecosystems with small, highly diverse, but understudied taxa.

Authors 6

1. Jan-Niklas Macher corresponding Aachen Department of Environmental Biology Institute of Environmental Sciences (CML) Naturalis Biodiversity Center

   Leiden University · Naturalis Biodiversity Center · University of Regensburg

   Affiliation as printed

   Department of Environmental Biology, Institute of Environmental Sciences (CML), Leiden University, 12 Einsteinweg 2, 2333 CC Leiden, The Netherlands

   Naturalis Biodiversity Center, Marine Biodiversity, Darwinweg 2, 2333 CR Leiden, The Netherlands

   Theoretical Ecology, University of Regensburg, Regensburg, Germany

2. Maximilian Pichler

   Bangor University · University of Regensburg

   Affiliation as printed

   Theoretical Ecology, University of Regensburg, Universitätsstr. 31, 93053 Regensburg, Germany

   Molecular Ecology and Evolution Group, School of Natural and Environmental Sciences, Bangor University, Bangor, Gwynedd, UK

3. Simon Creer

   Bangor University · Water Research Institute · National Research Council

   Affiliation as printed

   Molecular Ecology and Evolution Group, School of Natural and Environmental Sciences, Bangor University, Bangor, Gwynedd, UK

   National Research Council of Italy (CNR), Water Research Institute (IRSA), Verbania Pallanza, Italy

4. Alejandro Martínez

   Water Research Institute · National Research Council · University of Palermo

   Affiliation as printed

   National Research Council of Italy (CNR), Water Research Institute (IRSA), Largo Tonolli 50, 28922, Verbania Pallanza, Italy

   National Biodiversity Future Center (NBFC), Palermo, Italy

   National Research Council of Italy (CNR), Water Research Institute (IRSA), Verbania Pallanza, Italy

5. Diego Fontaneto Aachen Naturalis Biodiversity Center

   Naturalis Biodiversity Center · Water Research Institute · National Research Council · University of Amsterdam

   Affiliation as printed

   National Biodiversity Future Center (NBFC), Piazza Marina 61, 90133 Palermo, Italy

   National Research Council of Italy (CNR), Water Research Institute (IRSA), Largo Tonolli 50, 28922, Verbania Pallanza, Italy

   Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, the Netherlands

   Naturalis Biodiversity Center, Marine Biodiversity, Leiden, the Netherlands

6. - WILLEM RENEMA Aachen Naturalis Biodiversity Center Department of Environmental Biology Institute of Environmental Sciences (CML)

   Leiden University · Naturalis Biodiversity Center · University of Amsterdam

   Affiliation as printed

   Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands

   Naturalis Biodiversity Center, Marine Biodiversity, Darwinweg 2, 2333 CR Leiden, The Netherlands

   Department of Environmental Biology, Institute of Environmental Sciences (CML), Leiden University, Leiden, the Netherlands

   Naturalis Biodiversity Center, Marine Biodiversity, Leiden, the Netherlands