title: Ecological Intensification Through Pesticide Reduction: Weed Control, Weed Biodiversity and Sustainability in Arable Farming.
abstract: Amongst the biodiversity components of agriculture, weeds are an interesting model for exploring management options relying on the principle of ecological intensification in arable farming. Weeds can cause severe crop yield losses, contribute to farmland functional biodiversity and are strongly associated with the generic issue of pesticide use. In this paper, we address the impacts of herbicide reduction following a causal framework starting with herbicide reduction and triggering changes in (i) the management options required to control weeds, (ii) the weed communities and functions they provide and (iii) the overall performance and sustainability of the implemented land management options. The three components of this framework were analysed in a multidisciplinary project that was conducted on 55 experimental and farmer's fields that included conventional, integrated and organic cropping systems. Our results indicate that the reduction of herbicide use is not antagonistic with crop production, provided that alternative practices are put into place. Herbicide reduction and associated land management modified the composition of in-field weed communities and thus the functions of weeds related to biodiversity and production. Through a long-term simulation of weed communities based on alternative (?) cropping systems, some specific management pathways were identified that delivered high biodiversity gains and limited the negative impacts of weeds on crop production. Finally, the multi-criteria assessment of the environmental, economic and societal sustainability of the 55 systems suggests that integrated weed management systems fared better than their conventional and organic counterparts. These outcomes suggest that sustainable management could possibly be achieved through changes in weed management, along a pathway starting with herbicide reduction.
authors.affiliation: INRA, UMR1347 Agroécologie, BP 86510, 21000, Dijon, France. sandrine.petit2@dijon.inra.fr.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Petit
authors.affiliation: INRA, UMR1347 Agroécologie, BP 86510, 21000, Dijon, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Munier-Jolain
authors.affiliation: Centre d'Etudes Biologiques de Chizé, UMR 7372, CNRS - Université de La Rochelle, 79360, Villiers-en-Bois, France.|LTER «Zone Atelier Plaine & Val de Sèvre», Centre d'Etudes Biologiques de Chizé, CNRS, 79360, Villiers-en-Bois, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Bretagnolle
authors.affiliation: INRA, UMR1121, BP 20507, 68021, Colmar, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Bockstaller
authors.affiliation: INRA, UMR1347 Agroécologie, BP 86510, 21000, Dijon, France.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Gaba
authors.affiliation: INRA, UMR1347 Agroécologie, BP 86510, 21000, Dijon, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Cordeau
authors.affiliation: INRA, UMR1347 Agroécologie, BP 86510, 21000, Dijon, France.
authors.forename: Martin
authors.initials: M
authors.lastname: Lechenet
authors.affiliation: INRA, UMR1347 Agroécologie, BP 86510, 21000, Dijon, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Mézière
authors.affiliation: INRA, UMR1347 Agroécologie, BP 86510, 21000, Dijon, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Colbach
mesh_terms: D000383:Agriculture / Q000379:methods*; D044822:Biodiversity; D003247:Conservation of Natural Resources; D018556:Crops, Agricultural; D004463:Ecology; D006540:Herbicides; D057685:Plant Weeds / Q000502:physiology; D058728:Weed Control / Q000379:methods*
chemical_list: D006540:Herbicides
keywords: Agroecology; Biotic interactions; Crop production; Cropping system; Herbicide; Indicators