ANR (2019 - 2023) : GAMBAS

Generating Advances in Modeling Biodiversity And ecosystem Services (GAMBAS) : statistical improvements and ecological relevance of joint species distribution models

(official website)

Team involved : BIOM
Coordinator : Frédéric Mortier (Cirad, Montpellier)
Contact person LECA : Tamara Münkemüller (LECA, CNRS)

Abrupt climate change, land-use changes and other human-made disturbances are triggering species extinctions and range shifts, and are altering ecosystem functioning and services. Effective conservation strategies to mitigate these threats should build on a good understanding of how global changes affect biodiversity distribution and ecosystem services. In the last decades, much research has focused on a single (or at best a few) species at a time, its specific functional characteristics (i.e. traits) or ecosystem services, neglecting biotic interactions between species as well as synergies and trade-offs between traits and ecosystem services. However biodiversity is not merely the sum of species or their traits, but is the result of multiple interactions and feedbacks at various spatial and temporal scales, thus resulting in constrained species assemblages with characteristic trait distributions as well as bundles of ecosystem services. Global change studies that ignore these dependencies are prone to provide erroneous projections. Addressing these gaps requires a multi-scale approach that spans different fields of ecology and statistics with input from stakeholders and policymakers to ensure the results from the academic research can realistically be implemented.

Summary : Recently, a new generation of joint species distribution models has been proposed. These models can provide a better understanding and more accurate predictions of species distributions based on environmental variables while taking into account the effects of all other co-occurring species (e.g. competition). However, as promising as these models are in predictive ecology, the extensive use of JSDMs is still hampered by several limitations both on the ecological and statistical fronts. Our project GAMBAS aims to overcome these limitations with input from stakeholders and policy makers to ensure that the results from the theoretical research can realistically be implemented.
GAMBAS proposes significant advances to JSDMs and their use in ecology. We will overcome their most serious limitations and develop them towards a unified framework for modelling global change responses of biodiversity and ecosystem services by improving hand-in-hand their statistical features, their ecological interpretability and their applicability for policy makers. To ensure generality, we will test and apply our proposed novel developments to species, trait and ecosystem service data from a comprehensive collection of datasets comprising benchmark datasets (simulated data for which all true underlying interdependencies are known and two well-studied case-studies for which independent estimators of interdependencies are available) and three large-scale datasets from different ecosystems (terrestrial and water, temperate and tropical).
GAMBAS develops along three objectives :
– The first objective (O1, coordinated by T. Münkemüller) is to establish a classification of JSDMs to facilitate communication between researchers, to better understand the limitations and advantages of the models and thus their proper use.
– The second aim (O2, coordinated by F. Mortier) is related to mathematical developments that will strengthen and improve JSDMs.
– The third major objective (O3, coordinated by F. Gosselin) is dedicated to investigating the use of JSDMs through different ecological and practical prisms, in the context of defining conservation priority areas and adapting or developing biodiversity indicators.

 

Partners :

  • CIRAD, Montpellier (Forêts et Sociétés)
    – Mortier, Frédéric
    – Benedet, Fabrice
    – Cornu, Guillaume
    – Denis, Marie
    – Herault, Bruno
  • LECA - CNRS - Université Grenoble Alpes - Université Savoie Mont Blanc
    – Münkemüller, Tamara
    – Thuiller, Wilfried
    – Poggiato Giovanni
    – Bystrova Daria
    – Guéguen, Maya
    – Renaud, Julien
  • IRSTEA, Nogent sur Vernisson (Ecosystèmes Forestiers)
    – Gosselin, Frédéric
    – Laroche, Fabien
    – Piffady, Jérémy
  • MNHN, Paris (CESCO)
    – Jiguet, Frédéric
    – Fontaine, Benoît
    – Le Viol, Isabelle
  • Universite de Montpellier
    – Trottier, Catherine
    – Bry, Xavier
    – Toulemonde, Gwladys
  • Universite de Paris Sud
    – Coron, Camille

 

PhD Student at LECA :
– Giovanni Poggiato