Relative importance of region, seasonality and weed management practice effects on the functional structure of weed communities in French vineyards

Winegrowers have diversified their weed management practices over the last two decades changing structure and composition of communities. Complementary to taxonomic studies, trait-based approaches are promising ways for a better understanding community responses environmental agronomic filters. In present study, impacts climate, soil characteristics, seasons (chemical weeding, tillage mowing) were assessed on communities from 46 plots in three French wine-growing regions (Champagne, Languedoc Rhône valley). These agro-environmental gradients structuring according combinations traits highlighted using multivariate analysis (RLQ). The these filters Community Weighted Means (CWM) Variance (CWV) analysed mixed null modelling. Our results showed that spatio-temporal practice variables explained 13% 48% total variance CWM (specific leaf area, maximum height, seed mass, flowering onset duration lateral spread). Region, seasonality 53%, 28% 19% marginal variance, respectively. Weed impacted CWV through main gradients: (i) disturbance gradient with high mechanical tilled low chemically weeded (ii) vegetation cover abundance mowed compared barer soils plots. Languedoc, chemical weeding filtered ruderal strategy trait values (low small-stature) while more competitive (higher higher stature lower SLA). Champagne, favoured mass increases viability buried seeds spread associated ability resprout after tillage. This study demonstrated can be successfully applied perennial cropping systems such as vineyards, order understand assembly guide practices.