Habitat heterogeneity enables spatial and temporal coexistence of native and invasive macrophytes in shallow lake landscapes

J. Salgado* (Corresponding author), C.D. Sayer, N. Willby, A.G. Baker, B. Goldsmith, S. McGowan, T.A. Davidson, P. Bexell, I.R. Patmore, B. Okamura

*Corresponding author for this work

Research output: Contribution to journal/periodicalArticleScientificpeer-review

Abstract

Macrophyte invasive alien species (IAS) fitness is often hypothesised to be associated with beneficial environmental conditions (environmental matching) or species-poor communities. However, positive correlations between macrophyte IAS abundance and native plant richness can also arise, due to habitat heterogeneity (defined here as variation in abiotic and native biotic conditions over space and time). We analysed survey and palaeoecological data for macrophytes in satellite lakes along the Upper Lough Erne (ULE) system (Northern Ireland, UK), covering a gradient of eutrophication and connectivity to partition how environmental conditions, macrophyte diversity and habitat heterogeneity explained the abundance of Elodea canadensis, a widely distributed non-native macrophyte in Europe. E. canadensis abundance positively correlated with macrophyte richness at both the within- and between-lake scales indicating coexistence of native and invasive species over time. E. canadensis was also more prolific in highly connected and macrophyte-rich lakes, but sparser in the more eutrophic-isolated ones. Partial boosted regression trees revealed that in eutrophic-isolated lakes, E. canadensis abundances correlated with water clarity (negatively), plant diversity (positively), and plant cover (negatively) whereas in diverse-connected lakes, beta diversity (both positively and negatively) related to most greatly E. canadensis abundance. Dense macrophyte cover and unfavourable environmental conditions thus appear to confer invasibility resistance and sufficient habitat heterogeneity to mask any single effect of native biodiversity or environmental matching in controlling E. canadensis abundance. Therefore, in shallow lake landscapes, habitat heterogeneity variously enables the coexistence of native macrophytes and E. canadensis, reducing the often-described homogenisation effects of invasive macrophytes. © 2021 The Authors. River Research and Applications published by John Wiley & Sons Ltd.
Original languageEnglish
Pages (from-to)1387-1399
Number of pages13
JournalRiver Research and Applications
Volume38
Issue number8
DOIs
Publication statusPublished - 2022
Externally publishedYes

Keywords

  • boosted regression trees
  • connectivity
  • Elodea canadensis (Michx.)
  • eutrophication
  • metacommunities
  • paleolimnology

Fingerprint

Dive into the research topics of 'Habitat heterogeneity enables spatial and temporal coexistence of native and invasive macrophytes in shallow lake landscapes'. Together they form a unique fingerprint.

Cite this