Multifunctionality of agroecological vineyards: Complex interactions between functional and taxonomic diversity of service crops and ecosystem services

Agroecological practices in vineyards can enhance agroecosystems multifunctionality, by reducing pesticides use and their adverse effects on human health and the environment. However, growers remain concerned about potential negative impacts of plant diversification on grapevine performance, and existing literature report conflicting findings. This study employs both taxonomic and functional approaches to characterize weed communities in inter-rows of agroecological vineyards and assesses the effects of different plant diversification strategies-tillage (Tviti), service crop (Aviti), service crops and agroforestry (Dviti)- on soil quality, grapevine performance, and natural regulation processes over a two-year period in the south of France. Management practices shaped weed communities functional traits, with high tillage (Tviti) favoring acquisitive strategies plant communities. Those traits directly affected several of the indicators of services: service crops competed for soil resources, particularly nitrogen, affecting negatively grapevine yield and vigor. However, in 2023, more diverse systems (Aviti, Dviti) exhibited improved soil aggregate stability and increased natural enemy diversity. However, results varied significantly across years, highlighting the importance of environmental factors. Finally, no clear agroforestry effect was observed, likely due to the young age of the trees. A deeper understanding of the relationships between functional diversity and multiple ecosystem services in vineyards could help mitigate potential trade-offs associated with plant diversification. Furthermore, adapting management practices to local abiotic conditions and growers’ requirements is essential for optimizing both vineyard productivity and ecological sustainability. • Agroecological practices shaped the taxonomic and functional diversity of service crops. • Service crops improved soil structure and natural enemies' abundance. • Service crops reduced soil fertility and limited grapevine growth and yield. • Adaptive management is needed to limit grapevine–service crop competition.