Gembloux Agro-Bio Tech (GxABT)
Gembloux Agro-Bio Tech (GxABT)

Prédiction des zones favorables à l'installation de l'espèce exotique envahissante Ambrosia artemisiifolia L. en région wallonne

Delforge, Adrien ULiège
Promotor(s) : Monty, Arnaud ULiège
Date of defense : 27-Aug-2020 • Permalink :
Title : Prédiction des zones favorables à l'installation de l'espèce exotique envahissante Ambrosia artemisiifolia L. en région wallonne
Author : Delforge, Adrien ULiège
Date of defense  : 27-Aug-2020
Advisor(s) : Monty, Arnaud ULiège
Committee's member(s) : Mahy, Grégory ULiège
Fayolle, Adeline ULiège
Cornelis, Jean-Thomas ULiège
Branquart, Etienne 
Language : French
Number of pages : 70
Keywords : [en] ragweed
[en] ambrosia artemisiifolia
[en] Species distribution model
[en] invasive species
[en] Maxent
[en] walloon region
[en] ecological niche model
Discipline(s) : Life sciences > Environmental sciences & ecology
Target public : Researchers
Professionals of domain
Institution(s) : Université de Liège, Liège, Belgique
Degree: Master en bioingénieur : gestion des forêts et des espaces naturels, à finalité spécialisée
Faculty: Master thesis of the Gembloux Agro-Bio Tech (GxABT)


[en] The common ragweed (Ambrosia artemisiifolia L.) is an invasive alien species native to North America that has conquered Europe since the turn of the 20th century. Despite various observations in Belgium, the species has few presence data and is not very well-known in the Walloon region. The species causes extensive health and economic damage, as it is highly allergenic cultivated weed. Spatial modelling of areas favourable to the installation would allow better sensitization, as well as targeting of samples and management of the species.
This study brings together different modeling methods used in the literature in order to better understand the issues encountered by modeling invasive species. Using the presence points and the Worldclim bioclimatic rasters of the native area, a first modeling was carried out by extrapolation over the Walloon territory. A temporal extrapolation was also performed on the model, to point the impact of climate change on the potential distribution of common ragweed. A second modeling was carried out using environmental data from ‘Lifewatch Ecotope’ and the Walloon presence data, despite their poor robustness. The model was validated with the AUC index, and the results of the two models showed favorable areas over a large part of the Walloon territory in the provinces of Hainaut, Namur, Brabant Wallon and Liège.
The variables constraining the extrapolated model the most are summer temperatures and precipitation as well as the variation in precipitation. The variables constraining the independent model the most are the minimum winter temperatures, the distance to the railways and the presence of soils with average drainage. The temporal extrapolation has shown that almost all of the Walloon territory will be favorable to the colonization of the common ragweed, with the exception of the east of the province of Luxembourg and the east of the province of Liège. The independent model performed less well than the extrapolated model, mainly because of the weakness of the data set used.
It is important to remain attentive to the proliferation of common ragweed in the Walloon region. While it is not yet very harmful in the region, the potential damage it can cause is enough to raise as much awareness as possible among those involved in the introduction of the species and its management. It is essential to increase the number of observation points in the Walloon region in order to better understand the distribution of the species and to better fight against it in the future.



Access MEMOIRE_DelforgeAdrien.pdf
Size: 3.07 MB
Format: Adobe PDF


  • Delforge, Adrien ULiège Université de Liège > Gembloux Agro-Bio Tech


Committee's member(s)

  • Mahy, Grégory ULiège Université de Liège - ULiège > Département GxABT > Biodiversité et Paysage
    ORBi View his publications on ORBi
  • Fayolle, Adeline ULiège Université de Liège - ULiège > Département GxABT > Gestion des ressources forestières et des milieux naturels
    ORBi View his publications on ORBi
  • Cornelis, Jean-Thomas ULiège Université de Liège - ULiège > Département GxABT > Echanges Eau-Sol-Plantes
    ORBi View his publications on ORBi
  • Branquart, Etienne
  • Total number of views 142
  • Total number of downloads 594

All documents available on MatheO are protected by copyright and subject to the usual rules for fair use.
The University of Liège does not guarantee the scientific quality of these students' works or the accuracy of all the information they contain.