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International audience; Global forest loss and fragmentation have strongly increased the frequency of forest patches smaller than a few hectares. Little is known about the biodiversity and ecosystem service supply potential of such small woodlands in comparison to larger forests. As it is widely recognized that high biodiversity levels increase ecosystem functionality and the delivery of multiple ecosystem services, small, isolated woodlands are expected to have a lower potential for ecosystem service delivery than large forests hosting more species. We collected data on the diversity of six taxonomic groups covering invertebrates, plants and fungi, and on the supply potential of five ecosystem services and one disservice within 224 woodlands distributed across temperate Europe. We related their ability to simultaneously provide multiple ecosystem services (multiservice delivery potential) at different performance levels to biodiversity of all studied taxonomic groups (multidiversity), forest patch size and age, as well as habitat availability and connectivity within the landscape, while accounting for macroclimate, soil properties and forest structure. Unexpectedly, despite their lower multidiversity, smaller woodlands had the potential to deliver multiple services at higher performance levels per area than larger woodlands of similar age, probably due to positive edge effects on the supply potential of several ecosystem services. Biodiversity only affected multiservice delivery potential at a low performance level as well as some individual ecosystem services. The importance of other drivers of ecosystem service supply potential by small woodlands in agricultural landscapes also depended on the level of performance and varied with the individual ecosystem service considered. Synthesis and applications. Large, ancient woodlands host high levels of biodiversity and can therefore deliver a number of ecosystem services. In contrast, smaller woodlands in agricultural landscapes, especially ancient woodlands, have a higher potential to deliver multiple ecosystem services on a per area basis. Despite their important contribution to agricultural landscape multifunctionality, small woodlands are not currently considered by public policies. There is thus an urgent need for targeted policy instruments to ensure their adequate management and future conservation in order to either achieve multiservice delivery at high levels or to maximize the delivery of specific ecosystem services.

Fragmentation strongly shapes the distribution of organisms within forest patches through contrasting environmental conditions between the edge and interior habitat. Edge-to-interior distribution patterns are, however, poorly studied for litter- and soil-dwelling fauna, such as terrestrial gastropods, despite their high densities and significant impact on ecosystem processes, as both herbivores and detritivores. Therefore, we investigated edge-to-interior abundance patterns of terrestrial gastropods in 224 fragmented forest patches across Western Europe. Catching over 15,000 gastropods, we found that slug abundance is reduced in forest edges, while snail abundance shows no response on the edge effect. We hypothesize that these patterns could be explained by higher drought tolerance of snails, since forest edges have reduced air and soil humidity and elevated temperatures compared to forest interiors. Reduced slug abundance in forest edges potentially has ecological consequences for herbivory in and outside forest patches and nutrient cycling.