Continental-wide functional responses of a native and an invasive macrophyte to local environmental conditions

Freshwater biodiversity and ecosystem functioning are threatened by invasive macrophytes, which degrade habitat structure and disrupt key ecological processes. To support effective management and conservation, we need to identify how local, freshwater-specific drivers shape the distribution and performance of these species. Here, we present the first results from the project “Predicting DIVErsity of INvasive aquatic plants”, which investigates the mechanisms driving invasion performance in aquatic plants. We sampled 53 populations of the invasive Elodea nuttallii and 55 populations of the native Trapa natans (with invasive potential) across broad geographic and environmental gradients in Europe. For each population, we quantified leaf traits related to resource-use strategies (leaf area, specific leaf area, leaf dry matter content, pigment concentrations and nutrient content) and measured water and sediment variables. Using multivariate models, we describe trait-environment relationships, highlighting which conditions trigger a more performative response for these species. Therefore, our findings reveal habitats that are particularly vulnerable and where conservation or management actions should be prioritized. These continental-scale trait–environment relationships provide a baseline for the next phase of the project, in which we will compare species’ responses between native and invasive ranges by sampling and analysing the same species in North America.

Presentation Preference: Standard Oral (12 Minutes)

Primary Presenter: Alice Dalla Vecchia, University of Parma (alice.dallavecchia@unipr.it)

Authors:

Alice Dalla Vecchia, University of Parma  (alice.dallavecchia@unipr.it)

Lars Iversen, McGill University  (lars.iversen@mcgill.ca)

Roger Mormul, State University of Maringá  (roger@nupelia.uem.br)

Rossano Bolpagni, University of Parma  (rossano.bolpagni@unipr.it)