Background: The role of linear transportation infrastructures (roads, railways, oil and gas pipelines, power lines, rivers and canals) in fragmenting natural habitats is fully acknowledged. Up to now, the potential of linear transportation infrastructures verges (road and railway embankments, strips of grass under power lines or above buried pipelines, or waterway banks) as habitat or corridor for biodiversity, remains controversial. In a context of decreasing natural habitats, the opportunities of anthropogenic areas for contributing to wildlife conservation have to be considered. The present paper is the first synthesis of evidence about the potential of linear transportation infrastructure verges as corridor and/or habitat for insects in temperate landscapes. Methods:A systematic literature survey was made using two online publication databases, a search engine and by sending a call for literature to subject experts. Identified articles were successively screened for relevance on titles, abstracts and full texts using criteria detailed in an a priori protocol. We then used six specific questions to categorize and to critically appraise the retained studies. These questions encompassed the potential of verges as habitats and corridors for insects, and the effects of management and landscape context on these potentialities. A user-friendly database was created to sort the studies with low and medium susceptibility to bias. We used these studies to synthesize results of each specific question in a narrative synthesis. Finally, studies that met the meta-analysis requirements were used for a quantitative synthesis.Results: Our searches identified 64,206 articles. After critical appraisal, 91 articles that reported 104 studies were included in our review. Almost all of them had "control-impact" design, only two studies used "before-after-controlimpact" design, and one study used "before-after" design. In some cases, artificialization of transportation infrastructures lowered insect biodiversity while vegetation restoration had a moderate positive effect; the trend remained unclear for mowing/grazing practices. Urbanization and agriculture in the surroundings tended to lower the biodiversity hosted by verges, while natural and forested areas tended to promote it. No study dealt with the influence of management or surrounding landscape on insect dispersal along the verge. The small number of studies that compared the dispersal along verges and in habitats away from transportation infrastructures, together with the

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Background: Linear transportation infrastructures (roads, railways, oil and gas pipelines, powerlines and waterways) generate well documented fragmenting effects on species habitats. However, the potential of verges of linear transportation infrastructures (road and railway embankments, strips of grass under power lines or above buried pipelines, or waterway banks) as habitat or corridor for biodiversity, remains controversial. In a context of constant loss of natural habitats, the opportunities of anthropogenic areas for compensating the loss of biodiversity they generated have to be considered. This paper is the first synthesis of evidence addressing this topic for vertebrates (mammals, birds, amphibians and reptiles) in temperate ecosystems. Methods: We conducted a systematic literature survey using two online publication databases, three search engines, specialist websites, and by sending a call for literature to subject experts. We successively screened the articles for relevance on titles, abstracts and full texts using criteria detailed in an a priori protocol. We then used six specific questions to categorize the retained studies and to critically appraise them. These questions encompassed the potential of verges as habitats and corridors for vertebrates, and the effects of landscape and management on these potentialities. We critically appraised all studies to assess their risk of bias and created a database of the studies with low and medium risk of bias. We synthesized results for each specific question in narrative syntheses. Finally, studies that met meta-analysis requirements were used for quantitative syntheses. Results: Our initial searches identified 83,565 documents. After critical appraisal, we retained 119 documents that reported 128 studies. Most studies were conducted in Europe (49%) and in the United States of America (22%), and were about mammals (61%) and birds (20%). Results from the narrative synthesis and meta-analyses converged and revealed that the potential of linear transportation infrastructures verges to constitute a habitat for vertebrate species varies according to the infrastructure and the biological group considered. Especially, highway verges may be a refuge for small mammals but seems detrimental to birds. The potential also varied depending on the landscape considered, with urbanisation being related to lower biodiversity hosted by verges. We found a wide variety of verge

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29 Increasingly mechanized timber harvesting and the repeated use of skid trail 30 networks may affect ground vegetation differently at subsequent stages in the forest 31 rotation. At a fine scale, no studies have yet compared the influence of 32 micro-environmental factors and the effects of skid trail disturbance on ground flora 33 diversity. We investigated understory diversity patterns on skid trails in 30-, 50-and 34 63-year-old oak forests in the northern half of France. Subplots were placed on skid 35 trail center, wheel track, skid trail edge plus an off-trail control. At each subplot, we 36 measured soil moisture, soil compaction (penetration resistance and bulk density) and 37 photosynthetic active radiation and recorded the abundance of all vascular plants. The 38 richness and abundance of ground flora were calculated based on the classification of 39 their life form, seed bank persistence, light preference and moisture requirements. For 40 each ecological group, we found out its best diversity indicator from subplot location, 41 micro-environmental factors (soil moisture and compaction, light) and stand attributes 42 (stand type, basal area), then assessed the magnitude and negligibility of the effect of 43 the best indicator. 1) Higher soil compaction compared to controls was detected on 44 the tracks of skid trails in the 50-and 63-year-old stands. Neither soil moisture nor 45 light varied with subplot location whatever the stand type. 2) The best diversity 46 indicator that showed non-negligible effects included subplot location, and soil 47 moisture or soil compaction. Compared to controls, skid trails in the 50-and 48 63-year-old stands were richer in tree and short-term seed bank species, while skid 49 trails in the 30-year-old plots had no effect on ground flora. The abundance of tree 50 and shade-tolerant species was also higher on skid trails. Soil moisture was positively 51 correlated with the richness of low-and high-humidity species, shade-tolerant species 52 and transient seed bank species as well as with the abundance of short-term seed bank 53 species. Bulk density positively affected heliophilous species richness, while 54 penetration resistance was positively related to shrub abundance. Skid trails and soil 55 compaction in our research area had either no impact or a positive impact on ground 56 flora diversity. Longer-term studies of skid trail effects are needed to validate these 57 main findings.58 59

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1. The relative importance of local-and landscape-scale factors on butterfly diversity can depend on the quality, management intensity and landscape context of habitat patches. This study aims to disentangle these local and landscape effects on taxonomic and functional composition of butterfly communities within mosaic agricultural landscapes.2. We sampled butterflies in 144 grasslands and 142 linear elements (road verges and herbaceous strips between crops) in three regions in France. We analysed how local and landscape variables affected butterfly species richness, community composition and community-weighted mean traits.3. Local habitat variables explained more variation in butterfly richness and community composition than landscape-scale variables, both in grasslands and linear elements. Floristic composition was the most important predictor of butterfly community composition. In sites with tall vegetation and low biomass removal, butterfly communities were more dominated by species with long larval development, low fecundity and low mobility.4. Landscape variables were proportionally more influential in linear elements than in grasslands. Increasing landscape heterogeneity, by favouring agricultural mosaics with semi-natural grasslands and woodlands, appeared to be beneficial for butterflies, especially for specialist species.5. Agri-environmental schemes aiming at preserving butterfly diversity should thus primarily provide incentives to conserve or restore grasslands with low management intensity, while promoting at the same time landscape heterogeneity.