Running title: invasions in heterogeneous lake landscapes
Jorge Salgado1,2,3,4,(Jorge.SalgadoBonnet@nottingham.ac.uk), Carl D. Sayer2 (c.sayer@ucl.ac.uk), Nigel Willby8(n.j.willby@stir.ac.uk), Ben Goldsmith2 (b.goldsmith@ucl.ac.uk), Thomas A. Davidson5 (thd@bios.au.dk), Suzanne McGowan3 (Suzanne.Mcgowan@nottingham.ac.uk), Ambroise G. Baker2, 6, 7(a.baker@tees.ac.uk), Patrik Bexell2 (potrik.potrik@googlemail.com), Ian R. Patmore2 (i.patmore@ucl.ac.uk), Beth Okamura1(b.okamura@nhm.ac.uk).
1 Department of Life Sciences, Natural History Museum, London, UK
2 Environmental Change Research Centre, Department of Geography, University College London, London, UK
3 School of Geography, University of Nottingham, Nottingham, UK
4 Facultad de Ingeniería, Universidad Católica de Colombia, Bogotá, Colombia
5 Lake Group and Arctic Research Centre, Department of Bioscience, Silkeborg, Aarhus University, Aarhus, Denmark
6 School of Health and Life Science, Teesside University, Middlesbrough, UK
7 National Horizons Centre, Teesside University, Darlington, UK.
8 Biological and Environmental Sciences, University of Stirling, Stirling, UK
Key words : beta diversity, boosted regression trees, connectivity, Elodea canadensis , invasive species, metacommunities, plant cover, shallow lakes, species richness, species abundance
Type of article : Letters
Number of words in Abstract (150), Number of words in text (4994), number of references (58); number of figures (6)
Corresponding author : Jorge Salgado (Jorge.SalgadoBonnet@nottingham.ac.uk)
Statement of authorship : JS conceived the ideas; JS, BG, TD, CS, IP, PB, and BO collected the contemporary and palaeo‐ data; JS analysed the data and wrote the first manuscript; BO, CS, AB, NW, TD, SM contributed essentially to the interpretation and wording of the final version.
Data accessibility statement : should the manuscript be accepted, the data supporting the results will be archived in an appropriate public repository (Dryad, Figshare or Hal) and the data DOI will be included at the end of the article.
Abstract
Successful plant invasions are hypothesised to be associated with close environmental matching or species poor communities. However, positive correlations between non-native abundance and native plant richness can also arise due to habitat heterogeneity (defined here as variation in abiotic and biotic conditions over space and time). We analysed survey and palaeoecological data for macrophytes in lakes covering a gradient of eutrophication and connectivity to partition the roles of environmental matching, macrophyte diversity and habitat heterogeneity in explaining abundance and invasibility of Elodea canadensis , a widely distributed non-native macrophyte in Europe. There was no association between invasibility and macrophyte species richness. Instead habitat heterogeneity variously enabled the coexistence of native macrophytes and E. canadensis in lake metacommunities over time. Invasion resistance was associated with high native macrophyte cover and unfavourable environmental conditions. We show how spatial and temporal scales can determine the relationship between habitat heterogeneity and invasibility in lake systems.