Spatial and temporal diversity of service plant management strategies across vineyards in the south of France. Analysis through the Coverage Index

'Service plants' include spontaneous vegetation or sown species of cover crops associated with perennial crops in the rows or inter-rows with a high potential to provide ecosystem functions and services. In vineyards, service plants target specific services depending on the management strategy implemented by the winegrower, including the plant species, the surface covered, the plant growth control and destruction date. Understanding the management strategies linked to their associated target services at the regional scale is necessary to better help winegrowers, advisers and policy makers regarding an adapted use of service plants. To do this, we conducted a survey in 2016 among 334 winegrowers in Languedoc-Roussillon region in France, enquiring about their service plant management practices during the season 2014–2015. Given the diversity of the strategies of service plant management, we proposed a typology analyzing their spatial and temporal dimensions. Further, we present a Coverage Index (CI), which combines both temporal and spatial dimensions of the service plant management strategies. We conducted a multiple components analysis and clustering to create a vineyard typology and applied linear models to find correlations between the CI and specific vineyard characteristics. Three quarters of interviewed winegrowers sowed or maintained service plants in their vineyards; 41 % used a winter service plant strategy; 8.4 % a semi-permanent and 27.3 % a permanent service plant strategy. The preferred surface coverage strategy was full surface during grapevine dormancy and its reduction to half of the inter-rows after grapevine budburst. However, the diversity of surface coverage strategies during the grapevine vegetative period was remarkable. Lower water resources and specific soil characteristics were not linked to the service plant management strategies. Higher CI was associated with vineyards presenting quality labels (PDO and Organic), independent winemaking and lower target yields, showing that the added value of producing high quality wine plays an important role when implementing service plants in vineyards. Overall, our study showed: i) the popularity of spontaneous service plant strategies; ii) the spatial and temporal diversity of service plant management strategies and iii) the utility of the CI to study the implementation of service plants and to understand the motivations and constraints of their use.