Dynafor présent à la conférence conjointe de la NSO-GfÖ 2026

Romain Carrié, chercheur au laboratoire Dynafor actuellement en détachement pour 2 ans à l’Université de Lund en Suède a présenté ses recherches sur la gestion des adventices pour gérer le compromis entre production et biodiversité, au sein de la conférence conjointe de la NSO-GfÖ (Société Nordique d’Ecologie, Nordic Society Oikos ; Société Germanophone d’écologie, Gesellschaft für Ökologie) qui s'est tenue du 13 au 17 septembre 2026. Il y a présenté une communication orale dans la session thématique « Beyond Pesticides: When and How Diversity Regulates Pests in Agroecosystems ». intitulée: "Managing weeds in diversified farming systems, from the field to the landscape scales".

 Abstract:

Herbicides are among the most purchased pesticides in the EU, highlighting weeds as one of the most problematic pests for farmers. Although widely used in European cropping systems, herbicides pose significant threats to farming activities (herbicide resistance), the environment (water and air pollution) and to biodiversity (plant and insect decline). These negative externalities call for alternatives to manage weeds while preserving the environment. Due to the apparent immobility of weed species, weed management has focused on field-scale interventions involving practices with direct lethal effect such as herbicides and mechanical control. However, alternative practices, based on ecological knowledge of weed communities and their spatiotemporal drivers, can be implemented across a diversity of scales. Drawing on multiple studies we conducted, combining experimental and observational designs within a multiscale framework, we demonstrate how harnessing agronomic and ecological processes can support the design of weed-suppressing agricultural systems while minimizing environmental impacts. First, focusing on organic farming as a system particularly vulnerable to weed dynamics, we investigated the diversity of weed management strategies and how their interact with both weed pressure and weed diversity. We then experimentally manipulated organic farm management to examine ecological interactions underlying relationships between weed pressure, weed diversity and crop yield. Second, building on these weed pressure-diversity interactions, we explored how the multiscale implementation of extensive practices, such as organic farming or crop diversification, contributes to landscape-scale processes shaping species diversity in weed communities. Based on our findings, we identified key agroecological processes, linking agricultural management with biodiversity conservation, that can support the agroecological transition of agricultural systems.