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International audience; Aim: Species introductions have reshaped island faunas for the last 200 years, often threatening native biodiversity. Approximately equal numbers of native and alien species currently co-occur in the New Zealand avifauna, but they show distinct habitat use. Antagonistic interactions, habitat affinities and legacies of introduction history may concur to explain their segregation along habitat gradients. To investigate these processes, we explored how habitat, ecological traits and introduction history relate with the current composition of bird assemblages.Location New Zealand, Taxon BirdsMethods: We analysed 917 bird point counts spread along habitat and elevation gradients in the Canterbury region, South Island and related 10 ecological traits to landscape composition using a three-table ordination method known as “RLQ analysis”, accounting for spatial autocorrelation and phylogeny. We tested whether alien species’ positions in the RLQ were related to proxies of introduction history.Results: Eighteen endemic, 11 native and 19 alien species were distributed along a gradient from forest to open-habitat assemblages, in relation to foraging mode, nesting site and body size. A second gradient segregated species between native and exotic forests according to territoriality, sedentarity and diet. Traits accounted for the separation of native and alien bird species in forests, but not in open habitats. Phylogenetic signals emerged from the separation of native and alien species by forest type, and spatial structures suggested a landscape-level, rather than regional or local determinism. These correlations were independent of introduction history, although open-habitat assemblages tended to host alien species introduced later in time.Main conclusions: Habitat type and resource availability explain the spatial partitioning of New Zealand bird assemblages between native and alien species more consistently than competitive exclusion. We conclude that trait-mediated ecological differences among species have likely played a predominant role in species’ segregation among landscapes, while maintaining endemic bird assemblages in native forests.

Schall et al. (2020) assessed how a combination of different forest management systems in managed forest landscapes dominated by European beech may affect the biodiversity (alpha, beta and gamma) of 14 taxonomic groups. Current forest policy and nature conservation often demand for combining uneven-aged managed and unmanaged, set-aside for nature conservation, beech forests in order to promote biodiversity. In contrast to this, Schall et al. (2020) found even-aged shelterwood forests, represented by different developmental phases, to support highest regional (gamma) diversity. By pointing out that unmanaged forests included in our study are not old-growth forests, Bruun and Heilmann-Clausen (2021) challenge our conclusion as not providing sound scientific advice to societies. It is true that the studied unmanaged forests are not representing old-growth forests as defined in the literature. However, we demonstrate the representativeness of our unmanaged forests for current beech forest landscapes of Central Europe, where managed forests were more or less recently set-aside in order to develop old-growth structures. We also show that the managed and recently unmanaged forests in our study already differ distinctively in their forest structures. We use this response to stress the role of forest reserves for promoting certain species groups, and to emphasise their importance as valuable research sites today and in the future. Synthesis and applications. We see two main conclusions from our study. First, unmanaged forests still matter. We agree with Bruun and Heilmann-Clausen (2021) on the general importance of unmanaged, old-growth or long-untouched forests, and we do not question the importance of set-aside forests for biodiversity conservation. However, a complete complementarity to managed systems may only reveal after many decades of natural development. Second, safeguarding biodiversity in largely managed forest landscapes should focus on providing a landscape matrix of different developmental phases with varying environmental conditions rather than on maximising the vertical structure within stands. Such landscapes can partly compensate for structures that are still missing in vital, dense and closed forests recently set-aside or for unsuitable phases that may occur due to a cyclic synchronisation of forest structures in unmanaged forests. © 2021 The Authors. Journal of Applied Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society

Strong declines of grassland species diversity in small and isolated grassland patches have been observed at local and landscape scales. Here, we study how plant–herbivore interaction webs and habitat specialisation of leafhopper communities change with the size of calcareous grassland fragments and landscape connectivity. We surveyed leafhoppers and plants on 14 small (0.1–0.6 ha) and 14 large (1.2–8.8 ha) semi-natural calcareous grassland fragments in Central Germany, differing in isolation from other calcareous grasslands and in the percentage of arable land in the surrounding landscape (from simple to complex landscapes). We quantified weighted trophic links between plants and their phytophagous leafhoppers for each grassland fragment. We found that large and well-connected grassland fragments harboured a high portion of specialist leafhopper species, which in turn yielded low interaction diversity and simple plant-leafhopper food webs. In contrast, small and well-connected fragments exhibited high levels of generalism, leading to higher interaction diversity. In conclusion, food web complexity appeared to be a poor indicator for the management of insect diversity, as it is driven by specialist species, which require high connectivity of large fragments in complex landscapes. We conclude that habitat specialists should be prioritized since generalist species associated with small fragments are also widespread in the surrounding landscape matrix. Supplementary Information The online version contains supplementary material available at 10.1007/s00442-020-04830-6.

We investigated the landscape epidemiology of a globally distributed mammal, the wild pig (Sus scrofa), in Florida (U.S.), where it is considered an invasive species and reservoir to pathogens that impact the health of people, domestic animals, and wildlife. Specifically, we tested the hypothesis that two commonly cited factors in disease transmission, connectivity among populations and abundant resources, would increase the likelihood of exposure to both pseudorabies virus (PrV) and Brucella spp. (bacterial agent of brucellosis) in wild pigs across the Kissimmee Valley of Florida. Using DNA from 348 wild pigs and sera from 320 individuals at 24 sites, we employed population genetic techniques to infer individual dispersal, and an Akaike information criterion framework to compare candidate logistic regression models that incorporated both dispersal and land cover composition. Our findings suggested that recent dispersal conferred higher odds of exposure to PrV, but not Brucella spp., among wild pigs throughout the Kissimmee Valley region. Odds of exposure also increased in association with agriculture and open canopy pine, prairie, and scrub habitats, likely because of highly localized resources within those land cover types. Because the effect of open canopy on PrV exposure reversed when agricultural cover was available, we suggest that small-scale resource distribution may be more important than overall resource abundance. Our results underscore the importance of studying and managing disease dynamics through multiple processes and spatial scales, particularly for non-native pathogens that threaten wildlife conservation, economy, and public health. Supplementary Information The online version of this article (10.1007/s10393-020-01508-6) contains supplementary material, which is available to authorized users.

International audience; Farmers' use of fungicides and insecticides constitutes a major threat to biodiversity that is also endangering agriculture itself. Landscapes could be designed to take advantage of the dependencies of pests, pathogens and their natural enemies on elements of the landscape. Yet the complexity of the interactions makes it difficult to establish general rules. In our study, we sought to characterize the impact of the landscape on pest and pathogen prevalence, taking into account both crop and semi-natural areas. We drew on a nine-year national survey of 30 major pests and pathogens of arable crops, distributed throughout the latitudes of metropolitan France. We performed binomial LASSO generalized linear regressions on the pest and pathogen prevalence as a function of the landscape composition in a total of 39 880 field x year x pest observation series. We observed a strong disequilibrium between the number of pests or pathogens favored (15) and disadvantaged (2) by the area of their host crop in the landscape during the previous growing season. The impact of the host crop area during the ongoing growing season was different on pests than on pathogens: the density of most pathogens increased (11 of 17, and no decreases) while the density of a small majority of pests decreased (7 of 13, and four increases). We also found that woodlands, scrublands, hedgerows and grasslands did not have a consistent effect on the studied spectrum of pests and pathogens. Although overall the estimated effect of the landscape is small compared to the effect of the climate, a territorial coordination that generally favors crop diversity but excludes a crop at risk in a given year might prove useful in reducing pesticide use. Short abstract We sought to identify general rules characterizing the impact of the landscape on the prevalence of pests and pathogens of arable crops. We showed that the host crop area is consistently correlated with increased pressure of the pests and pathogens the following growing season. Correlations of pests and pathogens with host crop areas in the same year or with semi-natural components of the landscape (grasslands, hedgerows and forests) are less consistent and depend on the functional traits of the organisms involved.

Arthropod communities dwelling in adjacent habitats are able to impact one another via shared natural enemies. In agricultural landscapes, drastic differences in resource availability between crop and non-crop habitats cause variation in insect herbivore densities over short distances, potentially driving inter-habitat effects. Moreover, the composition of the landscape in which the habitats are embedded likely affects realised attack rates from natural enemies via impacts on local arthropod community structure. Here, we examine indirect effects between herbivore species within and between habitat types by calculating the potential for apparent competition between multiple populations. Firstly, we aim to determine how disparities in resource availability impact the strength of the potential for apparent competition occurring between habitats, secondly to examine the impact of landscape composition upon these effects, and finally to couch these observations in reality by investigating the link between the potential for apparent competition and realised attack rates. We used DNA metabarcoding to characterise host-parasitoid interactions within two habitat types (with divergent nutrient inputs) at 11 locations with variable landscape composition within an agroecosystem context. We then used these interaction networks to estimate the potential for apparent competition between each host pair and to compare expected versus realised attack rates across the system. Shared natural enemies were found to structure host herbivore communities within and across habitat boundaries. The size of this effect was related to the resource availability of habitats, such that the habitat with high nutrient input exerted a stronger effect. The overall potential for apparent competition declined with increasing land-use intensity in the surrounding landscape and exhibited a discernible impact on realised attack rates upon herbivore species. Thus, our results suggest that increasing the proportion of perennial habitat in agroecosystems could increase the prevalence of indirect effects such as apparent competition among insect herbivore communities, potentially leading to enhanced population regulation via increased attack rates from natural enemies like parasitoid wasps.

Primary production (PP) is a fundamental ecosystem function that influences several ecosystem services. However, little is known about how changes in landscape structure resulting from agricultural expansion affects forest and cropland production. We investigated the effect of landscape composition and configuration on the PP of forests and sugarcane crops in an old agricultural frontier of the Brazilian Atlantic forest. Using satellite images and a comprehensive dataset of vegetation indices that are proxies of PP (NDVI and EVI), we sampled 1201-km2 landscapes during the rainy and dry seasons of 2011–2016. In each landscape we quantified the indices, the percentage of sugarcane crops, the density of forest edges, and the number of forest patches. The NDVI and EVI of the entire landscape were negatively influenced by the percentage of croplands in both seasons and weakly affected by edge density and number of forest patches. When analyzing the NDVI of forests and croplands separately, both were negatively affected by the percentage of croplands. This indicates that forests and croplands are less productive in more deforested landscapes. The spatial variability of NDVI and EVI within the landscapes, estimated with coefficients of variation, was not affected by landscape attributes. Our findings indicate that landscape composition (i.e. forest cover) is more important than spatial configuration in determining the PP of forest and sugarcane crops, reinforcing the need to conserve forests in agricultural landscapes. We recommend reducing deforestation, restoring abandoned fields, protecting forest remnants and avoiding forest fragmentation to sustain more productive environmental-friendly agricultural landscapes.

Land clearing for agriculture results in fragmented landscapes with diminished resources for wildlife. Habitat loss and fragmentation are widespread problems; however, their impacts are rarely assessed simultaneously at multiple spatial and temporal scales. We used a focal site, multiscale design to examine how landscape characteristics that affect the probability of koala Phascolarctos cinereus presence varies over multiple spatial and temporal scales in a fragmented rural landscape in north-western New South Wales, Australia. We modelled the effect of variables representing landscape characteristics at three spatial extents – transect, patch and site – over three seasonal periods (mid-spring, late-spring and midsummer). Koala activity level (as determined by faecal pellets) varied between surveys, and identifies short-term seasonal changes in habitat use. Koala presence had the strongest association with patch scale variables (habitat suitability, soil fertility and patch area). Temporal variation in the effect of tree and landscape characteristics on koala presence highlights the limitations of surveys at a single point in time, and emphasizes that further research is needed to advance our understanding of what drives temporal variation in koala habitat use at multiple spatial scales. Our results show that to arrest declining koala populations in rural agricultural landscapes, conservation and management plans must consider landscape scale processes over a variety of time scales, and engage stakeholders across multiple properties and tenures, to conserve both disturbed and suitable habitat on private land.

Bees provide key pollination services for a wide range of crops. Accumulating evidence shows the effect of semi-natural habitats at the landscape level and local management practices on bee diversity in fields. However, most of the evidence is derived from studies in North America and Europe. Whether this paradigm is applicable in China, which is characterized by smallholder-dominated agricultural landscapes, has rarely been studied. In this study, we aimed to investigate how bee diversity affected apple production, and how landscape and local variables affected bee diversity and species composition on the Northern China Plain. The results showed that bees significantly increased apple fruit set compared to bagged controls. Wild bee diversity was positively related to apple seed numbers. Higher seed numbers reduced the proportion of deformed apples and thus increased fruit quality. Wild bee abundance was positively correlated with flowering ground cover, and both the abundance and species richness of wild bees were positively affected by the percentage of semi-natural habitats. We conclude that apple quality can benefit from ecological intensification comprising the augmentation of wild bees by semi-natural habitats and flowering ground cover. Future pollination management should therefore reduce the intensification level of management at both the local and landscape scales.

International audience; Context Nitrogen (N) and phosphorus (P) exports from rural landscapes can cause eutrophication of inland and coastal waters. Few studies have investigated the influence of the spatial configuration of nutrient sources-i.e. the spatial arrangement of agricultural fields in headwater catchments-on N and P exports. Objectives This study aimed to (1) assess the influence of the spatial configuration of nutrient sources on nitrate (NO3-) and total phosphorus (TP) exports at the catchment scale, and (2) investigate how relationships between landscape composition (% agricultural land-use) and landscape configuration vary depending on catchment size. Methods We analysed NO3- and TP in 19 headwaters (1-14 km(2), Western France) every two weeks for 17 months. The headwater catchments had similar soil types, climate, and farming systems but differed in landscape composition and spatial configuration. We developed a landscape configuration index (LCI) describing the spatial organisation of nutrient sources as a function of their hydrological distance to streams and flow accumulation zones. We calibrated the LCI's two parameters to maximise the rank correlation with median concentrations of TP and NO3-. Results We found that landscape composition controlled NO3- exports, whereas landscape configuration controlled TP exports. For a given landscape composition, landscape spatial configuration was highly heterogeneous at small scales (< 10 km(2)) but became homogeneous at larger scales (> 50 km(2)). Conclusions The spatial configuration of nutrient sources influences TP but not NO3- exports. An ideal placement of mitigation measures to limit diffuse TP export should consider both the hydrological distance to streams and flow accumulation zones.

International audience; Aim The spatio-temporal connectivity of forest patches in lowland agricultural landscapes and their age matter to explain current biodiversity patterns across regional as well as biogeographical extents, to the point that their effect exceeds the one of macroclimate for plant diversity in the understorey of temperate forests. Whether this remains true for other taxonomic groups is still largely unknown. Yet, this relative influence has important consequences for ecosystem functioning and the delivery of ecosystem services. Focusing on carabid beetle assemblages, we assessed the relative importance of macroclimatic, landscape and patch attributes in driving local species richness (alpha-diversity) and species dissimilarity between patches (beta-diversity).Location Deciduous forest patches in seven regions along a 2,100-km-long latitudinal gradient across the European temperate forest biome, from southern France to central Sweden.Methods We sampled 221 forest patches in two 5-km x 5-km landscape windows with contrasting management intensities. Carabid beetles were classified into four habitat-preference guilds: forest-specialist, forest-generalist, eurytopic and open-habitat species. We quantified the multi-level environmental influence using mixed-effects models and variation partitioning analysis.Results We found that both alpha- and beta-diversity were primarily determined by macroclimate, acting as a large-scale ecological filter on carabid assemblages among regions. Forest-patch conditions, including biotic and abiotic heterogeneity as well as patch age (but not patch size), increased alpha-diversity of forest species. Landscape management intensity weakly influenced alpha-diversity of forest species, but increased the number of non-forest species in forest patches. Beta diversity of non-forest species increased with patch heterogeneity and decreased with landscape management intensity.Main conclusions Our results highlight the leading role of broad macroclimatic gradients over local and landscape factors in determining the composition of local carabid communities, thereby shedding light on macroecological patterns of arthropod assemblages. This study emphasizes the urgent need for preserving ancient forest patches embedded in agricultural landscapes, even the small and weakly connected ones.

Farmland is one of the most important ecosystems in the world, providing foods and habitats for humans as well as many wild animals. However, biodiversity in farmlands has been substantially impacted by the intensification of agriculture and changes in landscape. Increasing either the area of natural and semi-natural habitat or the proportion of biodiversity-friendly crops could potentially mitigate the decline of biodiversity, but at the same time they would affect the agricultural economic output and were not widely applied. To date, some studies have focused on whether crops or cropland heterogeneity has a positive impact on biodiversity, but the results were inconsistent and it is difficult to summarize the relationship between farmland heterogeneity and farmland biodiversity in general. Meanwhile, few papers have studied the differences in bird diversity among small-scale agriculture in China. We conducted a year-long field survey on the Chengdu Plain to explore the relationships of landscape composition and the heterogeneity of cropland and non-cropland with bird diversity and community structure across different seasons. Using generalized linear models (GLM) and generalized least squares (GLS) for data analysis, our results showed that bird diversity is positively correlated with natural woodlands but negatively correlated with commercial forests. Both crop and non-crop landscape compositional heterogeneity affect bird diversity and community structure, especially during the non-breeding season, as many high-altitude birds come down to the farmland for foraging. Both bird diversity and community structure are influenced by cropland configurational heterogeneity, but seldomly influenced by non-cropland configurational heterogeneity. We propose to maintain the area of natural habitat and increase the area of mixed commercial forests by replacing monocultures. Diversified crop and non-crop types with a reasonable layout could conserve farmland biodiversity and maintain the stability of local ecosystems. More research on landscape heterogeneity in small-scale agriculture is needed to provide better understanding of the relationship between the agricultural landscape and bird diversity.

Wild bumblebees are key pollinators of crops and wild plants that rely on the continuous availability of floral resources. A better understanding of the spatio-temporal availability and use of floral food resources may help to promote bumblebees and their pollination services in agricultural landscapes. We placed colonies of Bombus terrestris L. in 24 agricultural landscapes with various degrees of floral resource availability and assessed different parameters of colony growth and fitness. We estimated pollen availability during different periods of colony development based on detailed information of the bumblebee pollen diet and the spatial distribution of the visited plant species. Total pollen availability did not significantly explain colony growth or fitness. However, when using habitat maps, the weight gain of colonies, the number of queen cells, and colony survival decreased with increasing distance from the forest. The better explanation of bumblebee performance by forest proximity than by (plant-inferred) pollen availability indicates that other functions of forests than pollen provision were important. The conservation of forests next to agricultural land might help to sustain high populations of these important wild pollinators and enhance their crop pollination services. Combining different mapping approaches might help to further disentangle complex relationships between B. terrestris and their environment in agricultural landscapes.

Habitat fragmentation threatens plant and pollinator communities, as well as their interactions. However, the effects of landscape fragmentation on the pollination of wild plant species are not well understood yet, partly because there are many correlated features in fragmented landscapes (e.g., decreased patch size, increased isolation, and patch complexity) whose influences are difficult to disentangle. Using a structural equation modeling approach, we assessed the direct and indirect effects of landscape fragmentation (patch size, isolation and complexity, percentage of surrounding land in forest) on the abundance, functional‐group richness, and evenness of pollinators of 24 habitat fragments within an agricultural landscape in Southern Norway. In addition, we studied how these variables affected visitation rates (visits per flower) and seed production (seed set, seed mass) in the four most abundant plant species in the area. Flower abundance was higher in larger and complex patches and decreased with the percentage of forest in the surroundings, while flower richness increased with patch complexity. We found a direct negative relationship between patch complexity and the overall number of pollinator visits that the habitat fragments received. Apart from this direct landscape effect, pollinator visits were mostly affected by the floral communities, with overall flower abundance and richness increasing both total number of pollinator visits and pollinator‐group richness, and flower richness having an additional negative influence on pollinator‐group evenness. Interestingly, we did not find any direct link between visitation rates and reproductive success for any of the study plant species. Instead, several landscape variables directly affected species seed production, although the effects of landscape on seed production were highly species specific. Patch complexity had a negative effect on seed production in two of the four focal species, while other components of the landscape had species‐specific effects. Increasing fragmentation of agricultural landscapes affects pollination interactions at the community level and the reproduction of wild plants. However, understanding the effects of fragmentation on seed production requires going beyond estimating visitation rates, since landscape effects on plant reproduction are not always related to overall interaction frequencies., This study was supported by the projects 170532/V40 and 11551017, financed by the Norwegian Research Council and the Norwegian University of Life Sciences, respectively. During the writing of this manuscript AL was supported by a Ramón y Cajal (RYC‐2015‐19034) contract from the Spanish Ministry of Science, Innovation and Universities, the Spanish State Research Agency, European Social Funds (ESF invests in your future) and the University of the Balearic Islands, and by project CGL2017‐89254‐R, financed by the Spanish Ministry of Economy and Competitiveness, Feder funds and the Spanish Research Agency.

1. Increasing landscape heterogeneity by restoring semi-natural elements to reverse farmland biodiversity declines is not always economically feasible or acceptable to farmers due to competition for land. We hypothesized that increasing the hetero-geneity of the crop mosaic itself, hereafter referred to as crop heterogeneity, can have beneficial effects on within-field plant diversity .2. Using a unique multi-country dataset from a cross-continent collaborative project covering 1,451 agricultural fields within 432 landscapes in Europe and Canada, we assessed the relative effects of compositional and configurational crop heteroge-neity on within-field plant diversity components. We also examined how these relationships were modulated by the position within the field. 3. We found strong positive effects of configurational crop heterogeneity on within-field plant alpha and gamma diversity in field interiors. These effects were as high as the effect of semi-natural cover. In field borders, effects of crop heterogeneity were limited to alpha diversity. We suggest that a heterogeneous crop mosaic may overcome the high negative impact of management practices on plant diversity in field interiors, whereas in field borders, where plant diversity is already high, landscape effects are more limited. 4. Synthesis and applications. Our study shows that increasing configurational crop heterogeneity is beneficial to within-field plant diversity. It opens up a new effec-tive and complementary way to promote farmland biodiversity without taking land out of agricultural production. We therefore recommend adopting manipulation of crop heterogeneity as a specific, effective management option in future policy measures, perhaps adding to agri-environment schemes, to contribute to the con-servation of farmland plant diversity. Natural Sciences and Engineering Research Council of Canada; German Ministry of Research and Education; Agence Nationale de la Recherche, Grant/Award Number: ANR-11-EBID-0004; Canada Foundation for Innovation; German Research Foundation; Spanish Ministry of Economy and Competitiveness; Agriculture and Agri-Food Canada; French National Research Agency, Grant/Award Number: ANR-11-EBID-0004; UK Government Department of the Environment, Food and Rural Affairs; Environment Canada (EC)

In Europe, agri-environmental schemes (AES) have been unsuccessful in halting biodiversity declines to any great extent. Two particular shortcomings of AES include the low farm uptake and the modest efficacy of many AES options. Partly in response to these shortcomings, initiatives encouraging farmers to take an active role in biodiversity conservation have gained in popularity. However, almost no evaluations of such initiatives exist. 2. We evaluated uptake of conservation advice on farms in the Swedish Volunteer & Farmer Alliance, a BirdLife Sweden-coordinated project aimed at farmland bird conservation, and the response of farmland birds to those actions using farm-level survey data, in a before-after implementation assessment. 3. Uptake was higher for unsubsidised (i.e. non-AES) measures than for AES options, and depended on farmers’ interest in nature, farm size (higher uptake on larger farms) and production type (higher on organic farms). 4. In general, abundances of non-crop nesting and field-nesting bird species declined between inventory years (median interval 3 years). Decreases were more marked in agriculturally marginal regions than in more arable-dominated regions, and declines were stronger on organic than conventional farms. 5. Negative abundance trends among non-crop nesting species were reduced by an increasing number of conservation measures at the farm, but only in the more arable-dominated landscapes. Changes in other non-crop species and in field-nesting species did not significantly relate to implemented measures, but the power to detect such effects was generally small due to the small sample size of high-uptake farms as well as high inter-farm variability. 6. Implications: Our results suggest that Volunteer Farmer Alliances and the addition of unsubsidised measures may be successful in changing the local number of non-crop nesting farmland birds at the farm level, and especially so in intensively managed agricultural landscapes. Thus, unsubsidised measures can be a useful addition to the set of agri-environment tools, although their effects on breeding bird numbers are (as with AES) dependent on landscape context, as well as on ensuring high on-farm uptake of different interventions.

Complex landscapes with high resource availability can support more diverse natural enemy communities and better natural pest control by providing resources and facilitating organism dispersal. Moreover, in agricultural landscapes, local agroecosystem management can support biodiversity maintenance and pest control by adding resources in less complex landscapes with fewer resources. However, we lack an understanding of how local and landscape factors interact to affect natural enemy communities and their site fidelity to agroecosystems in urban landscapes (i.e., cityscapes). To better understand how local and landscape factors influence natural enemies in urban agroecosystems, we used urban community gardens as a model system to test if and how local resource manipulation and differences in cityscape quality affect natural enemy (ladybird beetles, parasitoid wasps) communities and their fidelity to urban habitats. We performed two manipulations. First, we added local floral resources in 6 of 12 gardens situated in different cityscapes to measure differences in natural enemy biodiversity. Second, in those 12 gardens, with and without resource additions, we manipulated populations of a common natural enemy, Hippodamia convergens, to assess fidelity to the gardens. Floral resource additions increased parasitoid abundance and changed community composition, but had little effect on ladybeetle abundance, richness or site fidelity. Rather, ladybeetle fidelity to gardens was lower in gardens in low quality cityscapes with high impervious cover. Cityscape quality influences natural enemies in and fidelity to gardens. Landscape-moderated biodiversity patterns observed in rural landscapes likely differ from urban contexts with implications for pest control.

International audience; Edge contrast, is one of the main determinants of edge effects. This study examines the response of plant and pollinatordiversity (bees and butterflies) to forest edge contrast, i.e. the difference between forests and adjacent open habitats withdifferent disturbance regimes. We also investigated a potential cascading effect from plants to pollinators and whether edgestructure and landscape composition mediate the relationship between edge contrast and beta diversity of pollinators. Wesampled 51 low-contrast edges where forests were adjacent to habitats showing low levels of disturbance (i.e. grey dunes,mowed fire-breaks, orchards, grasslands) and 29 high-contrast edges where forests were adjacent to more intensively disturbedhabitats (i.e. tilled firebreaks, oilseed rape) in three regions of France. We showed that plant diversities were higher in edges thanin adjacent open habitat, whatever the edge contrast. However, plant beta diversity did not differ significantly between low andhigh-contrast edges. While we observed higher pollinator diversities in adjacent habitats than in low-contrast edges, there wereno significant differences in pollinator beta diversity depending on edge contrast. We did not observe a cascading effect from plants to pollinators. Plant and bee beta diversities were mainly explained by local factors (edge structure and flower cover)while butterfly beta diversity was explained by surrounding landscape characteristics (proportion of land cover in grassland).

International audience; Context Agroecosystems are dynamic, with yearly changing proportions of crops. Explicit consideration of this temporal heterogeneity is required to decipher population and community patterns but remains poorly studied. Objectives We evaluated the impact on the activity-density of two dominant carabid species (Poecilus cupreus and Anchomenus dorsalis) of (1) local crop, current year landscape composition, and their interaction, and (2) inter-annual changes in landscape composition due to crop rotations. Methods Carabids were sampled using pitfall-traps in 188 fields of winter cereals and oilseed rape in three agricultural areas of western France contrasting in their spatial heterogeneity. We summarized landscape composition in the current and previous years in a multi-scale perspective, using buffers of increasing size around sampling locations. Results Both species were more abundant in oilseed rape, and in landscapes with a higher proportion of oilseed rape in the previous year. P. cupreus abundance was negatively influenced by oilseed rape proportion in the current year landscape in winter cereals and positively by winter cereal proportion in oilseed rape. A. dorsalis was globally impacted at finer scales than P. cupreus. Conclusions Resource concentration and dilution-concentration processes jointly appear to cause transient dynamics of population abundance and distribution among habitat patches. Inter-patch movements across years appear to be key drivers of carabids’ survival and distribution, in response to crop rotation. Therefore, the explicit consideration of the spatiotemporal dynamics of landscape composition can allow future studies to better evidence ecological processes behind observed species patterns and help developing new management strategies.

Landscape transformations have been a central topic in landscape ecology due to their influence on ecosystem services and biodiversity conservation. Landscape dynamics can be very complex and one o...

1. In agricultural landscapes, arthropods provide essential ecosystem services such as biological pest control and pollination. Intensified crop management practices and homogenization of landscapes have led to declines among such organisms. Semi-natural habitats, associated with high numbers of these organisms, are increasingly lost from agricultural landscapes but diversification by increasing crop diversity has been proposed as a way to reverse observed arthropod declines and thus restore ecosystem services. However, whether or not an increase in the diversity of crop types within a landscape promotes diversity and abundances of pollinating and predaceous arthropods, and how semi-natural habitats might modify this relationship, are not well understood. 2. To test how crop diversity and the proportion of semi-natural habitats within a landscape are related to the diversity and abundance of beneficial arthropod communities , we collected primary data from seven studies focusing on natural enemies (carabids and spiders) and pollinators (bees and hoverflies) from 154 crop fields in Southern Sweden between 2007 and 2017. 3. Crop diversity within a 1-km radius around each field was positively related to the Shannon diversity index of carabid and pollinator communities in landscapes rich in semi-natural habitats. Abundances were mainly affected by the proportion of semi-natural habitats in the landscape, with decreasing carabid and increasing pollinator numbers as the proportion of this habitat type increased. Spiders showed no response to either crop diversity or the proportion of semi-natural habitats.

Context Landscape and local habitat traits moderate wild bee communities. However, whether landscape effects differ between local habitat types is largely unknown. Objectives We explored the way that wild bee communities in three distinct habitats are shaped by landscape composition and the availability of flowering plants by evaluating divergences in response patterns between habitats. Methods In a large-scale monitoring project across 20 research areas, wild bee data were collected on three habitats: near-natural grassland, established flower plantings and residual habitats (e.g. field margins). Additionally, landscape composition was mapped around the research areas. Results Our monitoring produced a dataset of 27,650 bees belonging to 324 species. Bee communities on all three habitats reacted similarly to local flower availability. Intensively managed grassland in the surrounding landscape had an overall negative effect on the studied habitats. Other landscape variables produced diverging response patterns that were particularly pronounced during early and late season. Bee communities in near-natural grassland showed a strong positive response to ruderal areas. Flower plantings and residual habitats such as field margins showed a pronounced positive response to extensively managed grassland and woodland edges. Response patterns regarding bee abundance were consistent with those found for species richness. Conclusion We advise the consideration of local habitat type and seasonality when assessing the effect of landscape context on bee communities. A reduction in the intensity of grassland management enhances bee diversity in a broad range of habitats. Moreover, wild bee communities are promoted by habitat types such as ruderal areas or woodland edges., publishedVersion

More than 30% of global crop plants rely on pollinators to set fruit or seed. While several studies have documented the negative effects of habitat degradation and distance from natural habitats on pollinator diversity in tropical areas, such studies have focused on single crops in particular areas without examining entire plant-pollinator communities. Here, we compared the plant-pollinator network structure between mixed fruit orchards that were near to (7 km) tropical forests and further investigated the effect of landscape composition in surrounding areas on plant-pollinator network structure. Our ten pairs of orchards were in Thailand and grew a range of tropical fruits pollinated by insects, birds and bats. The average number of visitor-flower interactions was higher at sites near the forest. Similarly, network robustness (the resistance of the network to losing species as a result of primary species removal) and interaction evenness (evenness of interactions among species) were higher at the sites closer to the forest. Robustness was strongly positively influenced by the proportion of lowland mosaic within a 1 km radius, while interaction evenness was positively affected by the proportion of urban area and montane mosaic within a 4 km radius of each site. Conservation of (semi-) natural habitats is therefore important for maintaining the diversity of wild pollinators and agricultural production.

1. Forest management greatly influences biodiversity across spatial scales. At the landscape scale, combining management systems that create different stand properties might promote biodiversity due to complementary species assemblages. In European beech forests, nature conservation and policy advocate a mixture of unmanaged (UNM) forests and uneven-aged (UEA) forests managed at fine spatial grain at the expense of traditionally managed even-aged shelterwood forests (EA). Evidence that such a landscape composition enhances forest biodiversity is still missing. 2. We studied the biodiversity (species richness 0D, Shannon diversity 1D, Simpson diversity 2D) of 14 taxonomic groups from bacteria to vertebrates in ‘virtual’ beech forest landscapes composed of varying shares of EA, UEA and UNM and investigated how γ-diversity responds to landscape composition. Groups were sampled in the largest contiguous beech forest in Germany, where EA and UEA management date back nearly two centuries, while management was abandoned 20–70 years ago (UNM). We used a novel resampling approach that created all compositional combinations of management systems. 3. Pure EA landscapes preserved a maximum of 97.5% γ-multidiversity (0D, 1D) across all taxa. Pure and mixed UEA/UNM landscapes reduced γ-multidiversity by up to 12.8% (1D). This effect was consistent for forest specialists (1D: −15.3%). We found only weak complementarity among management systems. 4. Landscape composition significantly affected γ-diversity of 6–9 individual taxa, depending on the weighting of species frequencies with strongest responses for spiders, beetles, vascular plants and birds. Most showed maximum diversity in pure EA landscapes. Birds benefited from UNM in EA-dominated landscapes. Deadwood fungi showed highest diversity in UNM. 5. Synthesis and applications. Our study shows that combining fine-grained forest management and management abandonment at the landscape scale will reduce, rather than enhance, regional forest biodiversity. We found an even-aged shelterwood management system alone operating at intermediate spatial scales and providing stands with high environmental heterogeneity was able to support regional biodiversity. However, some taxa require certain shares of uneven-aged and unmanaged forests, emphasizing their general importance. We encourage using the here presented resampling approach to verify our results in forest landscapes of different composition and configuration across the temperate zone., publishedVersion

Intensively managed flowering crops like canola (Brassicales: Brassicaceae) (oilseed rape, OSR) provide significant short-term nectar resources for pollen consumers. They may also play important roles as annual “service strips” in temporarily promoting predatory invertebrates. We set out to test this assumption by comparing overall and functional group-specific species richness, activity density, and assemblage composition of carabids (Coleoptera: Carabidae) and spiders (Araneae), in three types of service strips—OSR, woody, and grassy strips established in direct vicinity to cropland. OSR strips were found to harbor the highest carabid species richness and activity density of small carabids. The activity density of carabids overall and of omnivorous species, the species richness and activity density of spiders across size classes and feeding strategies were all significantly reduced in woody strips. The percentage of seminatural habitat in the wider landscape was positively linked to the activity density of spiders overall, ground hunting and large spiders, whereas in carabids, positive effects were limited to large species occurring in grassy strips. Habitat type was the main predictor of both carabid and spider assemblage composition. Our results indicate that carabid and spider activity density across functional groups responded more strongly to changes in the landscape composition than the diversity of individual taxonomic groups. For agricultural landscape management, the establishment of habitat mosaics that include regular OSR could promote abundant, species-rich predatory invertebrates particularly in early spring. In contrast, structurally homogenous woody strips represent limited value in promoting the investigated biological pest control agents.

There has been a growing concern for the urbanization induced local warming, and the underlying mechanism between urban thermal environment and the driving landscape factors. However, relatively little research has simultaneously considered issues of spatial non-stationarity and seasonal variability, which are both intrinsic properties of the environmental system. In this study, the newly proposed multi-scale geographically weighted regression (MGWR) is employed to investigate the seasonal variations of the spatial non-stationary associations between land surface temperature (LST) and urban landscape indicators under different operating scales. Specifically, by taking Wuhan as a case study, Landsat-8 images were used to achieve the LSTs in summer, winter and the transitional season, respectively. Landscape composition indicators including fractional vegetation cover (FVC), albedo and water percentage (WP) and urban morphology indicators covering building density (BD), building height (BH) and building volume density (BVD) were employed as potential landscape drivers of LST. For reference, the conventional geographically weighted regression (GWR) and ordinary least squares (OLS) regression were also employed. Results revealed that MGWR outperformed GWR and OLS in terms of goodness-of-fit for all seasons. For the specific associations with LST, all six indicators exhibited evident seasonal variations, especially from the transition season to winter. FVC, albedo and BD were observed to possess great spatial non-stationarity for all seasons, while WP, BH and BD tended to influence LST globally. Overall, FVC exhibited certain positive effect in winter. The negative effect of WP was the greatest among all indicators, although it became the weakest in winter. Albedo tended to influence LST more complicatedly than simple cooling. BD, with a consistent heating effect, was testified to have a greater influence on LST than BH for all seasons. The BH-LST association tended to transfer into positive in winter, while the BVD-LST association remained negative for all seasons. The results could support the establishment of season- and site-specific mitigation strategies. Generally, this study facilitates our understanding of human-environment interaction and narrows the gap between climate research and city management.

Biological diversity is influenced by many environmental factors, which can act either at a local scale (e.g. quality and quantity of feeding and nesting resources, habitat type) or at a landscape scale (e.g. habitat fragmentation, composition and configuration of landscape features). To effectively manage or promote biodiversity in heterogeneous environments such as intensive agrosystems, a thorough knowledge of the spatial and temporal scale of ecological factor effects is required. This study investigates the effects of ecological correlates on local wild bee diversity in semi-natural farmland habitats, and predicts changes in species richness according to local-scale and landscape-scale correlates to further guide bee conservation practices. Local floral richness, the proportion of semi-natural habitats in the landscape (1000 m radius) and the type of semi-natural habitats influenced bee richness at a field scale. However, the magnitude of the effect varied seasonally and according to local bee abundance. Model predictions showed that increasing floral richness on farms had a greater effect on bee richness than increasing the proportion of semi-natural habitats. While increasing the number of semi-natural habitats would be a more effective strategy for promoting bee diversity at the landscape scale, it may not be feasible in intensive farming systems. Fil: Rollin, Orianne. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural - Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Unité Mixte Technologique. Protection des Abeilles dans l’Environnement; Francia Fil: Pérez Méndez, Néstor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural - Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Institut de Recerca i Tecnologia Agroalimentàries; España Fil: Bretagnolle, Vincent. Centre National de la Recherche Scientifique; Francia. Université de la Rochelle; Francia Fil: Henry, Mickaël. Unité Mixte Technologique. Protection des Abeilles dans l’Environnement; Francia. Institut National de la Recherche Agronomique; Francia

Alterations in the composition and configuration of land uses during urbanization exert significant impacts on variations in soil phosphorus (P). Here, we analyzed the concentrations of soil total P and P fractions in 75 soil samples from vegetated lands with different urbanization intensity (UI) in western Chengdu, China. Characteristics of land use spatial pattern were investigated in 300 m buffer zones around each soil sample location according to five landscape metrics. The relationships between soil P variations and land use spatial patterns were analyzed by stepwise multiple regression. The results show that land uses exhibited highly fragmented, complex and heterogeneous features with increasing UI; concentrations of soil total P and P fractions, except for residual P, displayed accumulated trends. The built-up land and traffic green land predominated in medium- and high-UI landscapes and showed positive relationships with the soil P. By contrast, the cultivated land, forest land and industrial green land were more commonly distributed in low-UI landscapes and showed negative correlations with soil P. Furthermore, park green land, residential green land and public green land occupied small proportions of the study area and exhibited varied associations with soil P in landscapes with varied UI. The main factors affecting the soil P variations were the proportion of forest land, patch shape and landscape dispersion in a low-UI landscape. Soil P variations in medium-UI landscapes were controlled by the proportions of built-up land and residential green land, landscape dispersion and diversity. Additionally, soil P variations in high-UI landscapes only were regulated by the proportions of built-up land and public green land. The results reveal that the development of a variety of landscape planning schemes for different UI landscapes can be pivotal to maintaining or improving soil P balance, obtaining functional soil ecosystems, and securing a low environmental risk in urbanized areas.

Significant attention has recently been given towards understanding the hydrological effects of landscape structures. However, few studies have quantified the relationships between landscape structures and river water quality at different spatial scales. Here, we evaluated the influence of landscape structures, including structural composition and spatial configuration, on river water quality at scales ranging from riparian zones to entire regions. Water quality parameters (pH, Cl−, SO42−, DO, NO3−−N, NH4+−N, TP, and heavy metals) were determined from 38 sample sites in August 2018 during the wet season and January 2019 during the dry season. Landscape structures explained more of the water quality variation (ranging from 7% to 36%) in the near-distance buffer zones (100, 300, and 500 m), but slightly less (ranging from 2% to 27%) in the long-distance buffer zones (1000 m and entire regions). Landscape structures had the greatest impact on water quality at the 300-m buffer zone, and of all explanatory variables of landscape, joint effects between landscape composition and landscape configuration accounted for more than half of the variation in water quality. Moreover, different regional division methods considerably impacted the measured correlation between landscape structures and water quality. Compared with zonal division, a larger basin area division of sub-basin enhanced the correlation and associated significance between landscape composition and water quality. Concomitantly, the input of exogenous pollutants weakened the influence of mean dendritic stream length on the relationships between landscape structures and water quality. Overall, this study provides new insights into the relationships between landscape structures and river water quality. In future studies, selecting an appropriate regional division method is critical for revealing the effects of landscape structures on water quality. Furthermore, strengthening land-use management in the buffer zones near river banks is critical for protecting river water quality.

Conserving biodiversity on farmland is an essential element of worldwide efforts for reversing the global biodiversity decline. Common approaches involve improving the natural component of the landscape by increasing the amount of natural and seminatural habitats (e.g., hedgerows, woodlots, and ponds) or improving the production component of the landscape by increasing the amount of biodiversity‐friendly crops. Because these approaches may negatively impact on economic output, it was suggested that an alternative might be to enhance the diversity (compositional heterogeneity) or the spatial complexity (configurational heterogeneity) of land cover types, without necessarily changing composition. Here, we develop a case study to evaluate these ideas, examining whether managing landscape composition or heterogeneity, or both, would be required to achieve conservation benefits on avian diversity in open Mediterranean farmland. We surveyed birds in farmland landscapes of southern Portugal, before (1995–1997) and after (2010–2012) the European Union's Common Agricultural Policy (CAP) reform of 2003, and related spatial and temporal variation in bird species richness to variables describing the composition, and the compositional and configurational heterogeneity, of the natural and production components of the landscape. We found that the composition of the production component had the strongest effects on avian diversity, with a particularly marked effect on the richness of farmland and steppe bird species. Composition of the natural component was also influential, mainly affecting the richness of woodland/shrubland species. Although there were some effects of compositional and configurational heterogeneity, these were much weaker and inconsistent than those of landscape composition. Overall, we suggest that conservation efforts in our area should focus primarily on the composition of the production component, by striving to maximize the prevalence of biodiversity‐friendly crops. This recommendation probably applies to other areas such as ours, where a range of species of conservation concern is strongly associated with crop habitats.

Landscape dynamics are common phenomenon in the human‐dominated environments whereby it can be observed that the composition and configuration between landscape elements change over time. This dynamism brings about habitat loss and fragmentation that can greatly alter ecosystem services at patch, class, and landscape levels. We conducted a study to examine composition and configuration of forested landscape in the central highlands of Ethiopia using satellite images of over a period of four decades, and FRAGSTAT raster dataset was used to analyze fragmentation. Our result showed five land use/land cover (LULC) types in the study area. Cultivated land and settlement land increased at the expense of forestland, shrubland, and grassland. Fragmentation analysis showed the number of patches increased for all LULC types, indicating the level of fragmentation and interspersion. Juxtaposition increased for shrubland, grassland, and cultivated lands and decreased for settlement and forestland resulting in the fragmentation and isolation of patches. The study of LULC along with fragmentation at the landscape level can help improve our understanding of the pace at which conversion of landscape elements is happening and the impacts on ecosystem services as studies of LULC are courser in nature and would not show how each land use is reducing in size, proximity and shape among other things that determine ecosystem services. Such type of studies in rural landscapes are very vital to consider appropriate land management policies for the landscape level by taking into account the interaction between each element for sustainable development. We recommend land managers, conservationists, and land owners for observing the roles of each patch in the matrix to maximize the benefits than focusing on a single element.

Questions: Secondary succession in the tropics can follow alternative pathways. Land-use history is known to engender alternative successional communities, but the underlying mechanisms driving and sustaining divergence remain unclear. In this study we aim to answer the following questions: (1) does previous land use act as a filter for species composition in secondary forests; and (2) what are the relative roles of management practices, soil properties and landscape composition in determining species composition?. Location: Central Amazon, Brazil. Methods: We sampled trees, shrubs and palms (≥1cm diameter) in 38 early secondary forests (5 yr after abandonment) located along gradients of land-use intensity in five shifting cultivation landscapes. We measured the diameter and height of each sampled plant, identified it to species or morpho-species level and checked if it was resprouting or not. At each secondary forest we also collected soil samples for chemical and physical analyses and estimated the amount of old-growth forest surrounding it (landscape composition). Results: We found that previous land-use intensity determined species composition. With increasing land-use intensity, management practices of cut-and-burn and associated reduction in soil quality filtered out seed-dependent species and favoured strong sprouters and species that can cope with low nutrient availability. Landscape composition had a weak effect on species assemblages. We found specific species assemblages and indicator species associated with different levels of previous land-use intensity. As a consequence of these local filters, species α- and β-diversity decreased and therefore early successional communities became more similar to each other. Conclusion: Species composition of successional forests is strongly determined by different land-use intensities. Dispersal limitation has a limited effect on determining the composition of the dominant species. Filtering effects of management practices and soil quality determine the species dominating the canopy at early stages of succession and narrow down the range of species able to colonize and establish. This study highlights how land use shapes successional communities and suggests that alternative successional pathways are determined at early stages of succession. Therefore, accounting for land-use history is crucial to improve the understanding of tropical secondary succession. We present a list of indicator species for different levels of previous land-use intensity that can be used to support conservation and restoration decisions in the Amazon. © 2016 The Authors. Journal of Vegetation Science published by John Wiley & Sons Ltd on behalf of Internation Association of Vegetation Science

Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were negatively related to the cover of MFCs in the landscape. In SNHs, densities of bumblebees declined with increasing cover of MFCs but densities of honeybees increased. The densities of all pollinators were generally unrelated to the cover of SNHs in the landscape. Although MFC fields apparently attracted pollinators from SNHs, in landscapes with large areas of MFCs they became diluted. The resulting lower densities might negatively affect yields of pollinator-dependent crops and the reproductive success of wild plants. An expansion of MFCs needs to be accompanied by pollinator-supporting practices in agricultural landscapes., The study was funded by the EU FP7 project “Status and Trends of European Pollinators” (244 090, www.STEP-project.net) and Biodiversa‐FACCE project “Enhancing biodiversity‐based ecosystem services to crops through optimised densities of green infrastructure in agricultural landscapes” (PCIN‐2014‐048, http://www.cec.lu.se/research/ecodeal). JPGV and MV acknowledge support from the Severo Ochoa Program for Centres of Excellence in R+D+I (SEV‐2012‐0262), and FLORMAS (CGL 2012‐33801). JBW, VJW, SGP and SPMR acknowledge the support of Insect Pollinators Initiative research funded jointly by a grant from BBSRC, Defra, NERC, the Scottish Government and the Wellcome Trust, under the Living with Environmental Change Partnership. HGS and RB were supported by the Swedish Research Council FORMAS. JS and DK were supported by the Dutch Ministry of Economic Affairs (BO‐11‐011.01‐011 and KB‐14‐003‐006), AH and ISD were supported by the DFG Collaborative Research Centre 1047 Insect timing, and ISD and MD through the 2013–2014 BiodivERsA/FACCE – JPI project Ecodeal with national funding from BMBF.

Bees provide important pollination services for crops, but pollination limitation is a common problem in agricultural landscapes worldwide. To promote ecological intensification in fruit production, more knowledge is needed concerning the interacting effects of insect pollination services and soil fertility on crop quality and quantity. We investigated the effects of three pollination treatments (open, self and hand pollination) on apple quantity and quality parameters. We also analyzed the effects of bee abundance (wild bees and managed honeybees (Apis mellifera)) and soil nitrogen on fruit quantity and quality, and the responses of bee abundance and species richness to landscape metrics. Apple fruit set and yield of open pollinated flowers increased by 57 % and 25 t/ha (compared to bagged controls), respectively. Hand pollination further enhanced yields by 7 t/ha (compared to open pollination; i.e. to 39 t/ha), indicating pollination limitation in the orchards. Seed number was highest in open pollinated fruits, and increased with bee abundance if soil nitrogen was low, but decreased with bee abundance at high nitrogen levels, possibly due to higher flower density resulting in pollinator dilution effects. Higher seed numbers reduced the proportion of deformed apples and thus increased fruit quality. The percent of surrounding semi-natural habitats positively affected species richness of wild bees in apple orchards. We conclude that yield and quality of apples may benefit from ecological intensification comprising the augmentation of wild bees by semi-natural habitat and lowering of fertilizer inputs.

Discerning potential effects of insecticides on honey bee colonies in field studies conducted under realistic conditions can be challenging because of concurrent interactions with other environmental conditions. Honey bee colony models can control exposures and other environmental factors, as well as assess links among pollen and nectar residues in the landscape, their influx into the colony, and the resulting exposures and effects on bees at different developmental stages. We extended the colony model BEEHAVE to represent exposure to the insecticide clothianidin via residues in pollen from treated cornfields set in real agricultural landscapes in the US Midwest. We assessed their potential risks to honey bee colonies over a 1‐yr cycle. Clothianidin effects on colony strength were only observed if unrealistically high residue levels in the pollen were simulated. The landscape composition significantly impacted the collection of pollen (residue exposure) from the cornfields, resulting in higher colony‐level effects in landscapes with lower proportions of semi‐natural land. The application of the extended BEEHAVE model with a pollen exposure‐effects module provides a case study for the application of a mechanistic honey bee colony model in pesticide risk assessment integrating the impact of a range of landscape compositions. Environ Toxicol Chem 2019;38:423–435. © 2018 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC., Overview of pollen exposure‐effects module added to BEEHAVE. © 2018 SETAC

Biodiversity conservation and agricultural production are often seen as mutually exclusive objectives. Strategies for reconciling them are intensely debated. We argue that harmonization between biodiversity conservation and crop production can be improved by increasing our understanding of the underlying relationships between them. We provide a general conceptual framework that links biodiversity and agricultural production through the separate relationships between land use and biodiversity and between land use and production. Hypothesized relationships are derived by synthesizing existing empirical and theoretical ecological knowledge. The framework suggests nonlinear relationships caused by the multifaceted impacts of land use (composition, configuration, and intensity). We propose solutions for overcoming the apparently dichotomous aims of maximizing either biodiversity conservation or agricultural production and suggest new hypotheses that emerge from our proposed framework.

Although increasing landscape complexity is often advocated as a key intervention to sustain pest biocontrol, little is known on how increasing semi-natural habitats surrounding the crop can directly affect the density and damage of generalist pests. Our aim was to test how semi-natural habitats in the landscape influences the density and the impact of spotted wing drosophila (SWD) on sweet cherry. SWD is invasive pest native of South-East Asia that causes severe yield losses in several crops worldwide. We selected 32 conventional cherry orchards in NE Italy surrounded by landscapes with different proportions of forest and we quantified both pest density and crop damage using sentinel fruits. We observed a larger attack density in orchards surrounded by higher forest cover. The same trend was observed for female adult density. Forest habitats may provide ideal microclimatic conditions and alternative host plants that can promote population growth. The effect size of forest cover on both adult density and crop damage, despite the very large tested forest gradient (0–60%), suggests that a reduction of forest cover does not seem to be a viable option for controlling SWD. Indeed, semi-natural habitats can deliver multiple fundamental ecosystem services to the crops (e.g. biocontrol). However, current integrated pest management should take into account landscape composition and interventions should be particularly timely in forested landscapes where SWD can quickly attack the crop at higher density.

Managing landscape connectivity is a widely recognized overarching strategy for conserving biodiversity in human-impacted landscapes. However, planning the conservation and management of landscape connectivity of multiple and ecologically distinct species is still challenging. Here we provide a spatially-explicit framework which identifies and prioritizes connectivity conservation and restoration actions for species with distinct habitat affinities. Specifically, our study system comprised three groups of common bird species, forest-specialists, farmland-specialists, and generalists, populating a highly heterogeneous agricultural countryside in the southwestern Iberian Peninsula. We first performed a comprehensive analysis of the environmental variables underlying the distributional patterns of each bird species to reveal generalities in their guild-specific responses to landscape structure. Then, we identified sites which could be considered pivotal in maintaining current levels of landscape connectivity for the three bird guilds simultaneously, as well as the number and location of sites that need to be restored to maximize connectivity levels. Interestingly, we found that a small number of sites defined the shortest connectivity paths for the three bird guilds simultaneously, and were therefore considered key for conservation. Moreover, an even smaller number of sites were identified as critical to expand the landscape connectivity at maximum for the regional bird assemblage as a whole. Our spatially-explicit framework can provide valuable decision-making support to conservation practitioners aiming to identify key connectivity and restoration sites, a particularly urgent task in rapidly changing landscapes such as agroecosystems.

International audience; Efficient management of agricultural management should consider multiple services and stakeholders. Yet, it remains unclear how to guarantee ecosystem services for multiple stakeholders' demands, especially considering the observed biodiversity decline following reductions in semi-natural habitat (SNH), and global change. Here, we use an ecosystem service model of intensively-managed agricultural landscapes to derive the best landscape compositions for different stakeholders' demands, and how they vary with stochasticity and the degree of pollination dependence of crops. We analyse three groups of stakeholders assumed to value different ecosystem services most-individual farmers (crop yield per area), agricultural unions (landscape production) and con-servationists (biodiversity). Additionally, we consider a social average scenario that aims at maximizing mul-tifunctionality. Trade-offs among stakeholders' demands strongly depend on the degree of pollination dependence of crops, the strength of environmental and demographic stochasticity, and the relative amount of an ecosystem service demanded by each stakeholder. Intermediate amounts of SNH deliver relatively high levels of the three services (social average). Our analysis further suggests that the current levels of SNH protection lie below these intermediate amounts of SNH in intensively-managed agricultural landscapes. Given the worldwide trends in agriculture and global change, current policies should start to consider factors such as crop type and stochasticity, as they can strongly influence best landscape compositions for different stakeholders. Our results suggest ways of managing landscapes to reconcile several actors' demands and ensure for biodiversity conservation and food production.

With climate change, the effect of global warming on snow cover is expected to cause range expansion and enhance habitat suitability for species at their northern distribution limits. However, how this depends on landscape topography and sex in size-dimorphic species remains uncertain, and is further complicated for migratory animals following climate-driven seasonal resource fluctuations across vast landscapes. Using 11 years of data from a partially migratory ungulate at their northern distribution ranges, the red deer (Cervus elaphus), we predicted sex-specific summer and winter habitat suitability in diverse landscapes under medium and severe global warming. We found large increases in future winter habitat suitability, resulting in expansion of winter ranges as currently unsuitable habitat became suitable. Even moderate warming decreased snow cover substantially, with no suitability difference between warming scenarios. Winter ranges will hence not expand linearly with warming, even for species at their northern distribution limits. Although less pronounced than in winter, summer ranges also expanded and more so under severe warming. Summer habitat suitability was positively correlated with landscape topography and ranges expanded more for females than males. Our study highlights the complexity of predicting future habitat suitability for conservation and management of size-dimorphic, migratory species under global warming.

International audience; Farmland biodiversity and its associated ecosystem services are affected by agricultural activities at multiple spatial scales. Among these services, the regulation of weeds by invertebrate seed predators has received much attention recently but little is known about the relative effect of local management and landscape context of fields on this process. We monitored seed predation on four common weed species and carabid communities in 28 winter-cereals fields during five consecutive weeks in spring 2010. These fields were situated in contrasted landscape contexts and varied in terms of intensity of pesticide treatments and soil tillage regimes. Weed seed predation was strongly and positively related to the Shannon diversity of (strictly) granivorous carabids and to the activity-density of omnivorous carabids but negatively to the richness of omnivorous carabids. Weed seed predation and granivore diversity were positively related to landscape diversity and the proportion cover of temporary grassland within a 1000m radius around focal fields and were negatively affected by the intensity of local pesticide treatments. No-till systems sheltered higher diversity of granivorous carabids but did not show higher seed predation rates. We showed that landscape composition factors had a higher relative influence than local practices factors on weed seed predation service. Consequently, weed management strategies should not only consider the management of single fields but also the surrounding landscape to preserve carabid biodiversity and enhance weed seed predation service.

SPEGESTADCT3EACT4SUPDAT INRA; Assuring future crop yields whilst minimising impacts of agriculture on the environment requires that we adopt managements that replace pesticides by fostering pest regulation. However, large-scale empirical evidence for in-field and landscape properties supporting natural enemy abundance and their regulation of pests, as an ecosystem service in agriculture, is scarce. Using data from 67 arable fields, we examined whether the duration of adoption of in-field conservation agricultural practices (CA) and the landscape context of those arable fields explains the levels of in-field weed seed predation. Our results indicate that landscape and CA, in interaction, do indeed explain a large proportion of the observed variation in weed seed predation in-field. CA practice maintains high in-field abundances of carabids, but only after a period of four years of adoption. Prior to this, carabid abundance was only high for fields in landscapes with high percentage cover of arable crops and/or permanent grassland. Our work shows that the effect of landscape composition is conditional on local in-field management and that both local and landscape scales can be used to enhance the abundance of carabid beetles and the amount of seed predation in arable fields.

Cixiid planthoppers are considered of major economic importance, as they can transmit phytoplasmas responsible for many plant diseases. While thorougly studied in vineyards, the epidemiology of stolbur phytoplasma, transmitted by Hyalesthes obsoletus Signoret, was rarely investigated on minor crops as lavender, where it leads to ‘yellow decline’ disease and large economic losses. The objective of this paper is to understand the effect of the local landscape characteristics on the presence and density of H. obsoletus in the ‘Plateau de Valensole’, southern France. Potential host plants of H. obsoletus were surveyed in three contrasted zones (in terms of crops and disease intensity), by uprooting plants and capturing adults in emergence traps. The localization and potential movements of H. obsoletus from the host plants towards lavandin (infertile hybrid of lavender) were determined using yellow sticky traps. Clary sage plants were found as major hosts of H. obsoletus. Flying insects were also caught in fields of lavandin, although emergence traps and plant uprooting did not confirm this crop as a winter host, i.e., as a reservoir for the insect. Based on one zone, we showed that attractiveness may depend on crop (clary sage or lavandin) and on its age, as well as on the distance to the supposed source field. These results suggest that clary sage could be an important host of H. obsoletus, whose density largely varies between zones. Genetic studies would be required to confirm the role of clary sage in the dissemination of yellow decline of lavandin.

Aim: Biodiversity is rapidly disappearing at local and global scales also affecting the functional diversity of ecosystems. We aimed to assess whether functional diversity was correlated with species diversity and whether both were affected by similar land use and vegetation structure drivers. Better understanding of these relationships will allow us to improve our predictions regarding the effects of future changes in land use on ecosystem functions and services. Location: The Netherlands. Methods: We compiled a dataset of c. 3 million observations of 66 out of 106 known Dutch butterfly species collected across 6,075 sampling locations during a period of 7 years, together with very high-resolution maps of land use and countrywide vegetation structure data. Using a mixed-effects modelling framework, we investigated the relationship between functional and species diversity and their main land use and vegetation structure drivers. Results: We found that high species diversity does not translate into high functional diversity, as shown by their different spatial distribution patterns in the landscape. Functional and species diversity are mainly driven by different sets of structural and land use parameters (especially average vegetation height, amount of vegetation between 0.5 and 2 m, natural grassland, sandy soils vegetation, marsh vegetation and urban areas). We showed that it is a combination of both vegetation structural characteristics and land use variables that defines functional and species diversity. Main conclusions: Functional diversity and species diversity of butterflies are not consistently correlated and must therefore be treated separately. High functional diversity levels occurred even in areas with low species diversity. Thus, conservation actions may differ depending on whether the focus is on conservation of high functional diversity or high species diversity. A more integrative analysis of biodiversity at both species and trait levels is needed to infer the full effects of environmental change on ecosystem functioning.

Weed management is a critical issue as it is faced with a daunting set of challenges linked to crop productivity and farmland biodiversity. Developing new strategies for weed management requires a clear understanding of the relative role of local management and landscape heterogeneity on weeds. Yet few studies have investigated the combined effect of these factors on a variety of weed metrics that reconcile agronomical and ecological aims. Here, we analyzed the relative role of local management intensity and landscape heterogeneity according to the distance to field margin on four weed metrics (species richness, density, biomass and seed rain) and community composition in 257 fields (beet, maize, spring and winter rape fields) across Great Britain. Generalized mixed effect models followed by a model averaging procedure were applied on weed metrics and permutational multivariate analyses of variance were applied on weed species composition. Our analysis confirmed the overriding role of the distance to field margin on weeds. Although weed density and seed rain negatively responded to local management intensity, they did not respond in the same way to landscape configurational heterogeneity, namely the field size. We found interactions between management intensity and landscape heterogeneity but only in relation to weed biomass in beet and spring rape fields and to seed rain in beet fields. The relative importance of local management intensity and landscape heterogeneity varied depending on the distance to field margin, which can be attributed to spatial heterogeneity in management practices. We recommend that not only species richness but also a wide range of metrics should be considered in weed studies as they did not responded in the same way to local and landscape factors. We conclude that weed management strategies should be thought by integrating a multi-level approach as the combined effects of local management and landscape heterogeneity are likely to both reduce weed infestation whilst enhancing biodiversity.

The expansion of pollinator-dependent crops, especially in the developing world, together with reports of worldwide pollinator declines, raises concern of possible yield gaps. Farmers directly reliant on pollination services for food supply often live in regions where our knowledge of pollination services is poor. In a manipulative experiment replicated at 23 sites across an Ethiopian agricultural landscape, we found poor pollination services and severe pollen limitation in a common oil crop. With supplementary pollination, the yield increased on average by 91%. Despite the heterogeneous agricultural matrix, we found a low bee abundance, which may explain poor pollination services. The variation in pollen limitation was unrelated to surrounding forest cover, local bee richness and bee abundance. While practices that commonly increase pollinators (restricted pesticide use, flower strips) are an integral part of the landscape, these elements are apparently insufficient. Management to increase pollination services is therefore in need of urgent investigation.

International audience; Human activities may generate geometrical landscape (i.e. composed of rectilinear and repetitive landscape units) structures that can significantly influence the spatial distribution of birds. While bird distribution in various landscape types has been extensively studied, the role played by landscape configuration and composition in different facets of bird diversity remains unclear. Here, these two main components of landscape characteristics (i.e. configuration and composition) are disentangled and their relative influence on three different facets of bird assemblages: taxonomic and functional characteristics, and the presence of rare species, is tested. We chose four large coastal salinas ofWestern France as a relevant model of geometrical and human-dominated landscapes where each landscape unit can be easily identified and mapped. The landscape characteristics of these sites were mapped and quantified. Then, terrestrial breeding birds were sampled in 172 point-counts using a standardized protocol. 69 diurnal terrestrial bird species were detected and considered in analyses (waterbirds and owls excluded). Landscape composition was found to have a higher influence on bird communities than landscape configuration, which fits with the “landscape composition hypothesis”. More specifically, the most “extreme” landscapes — those with low terrestrial surface areas, low landscape richness and diversity, low cohesion, and very patchy landscapes with complex geometrical shapes — host the lowest bird taxonomic abundance, richness and diversity and functional richness, but are characterized by the presence of rare species (mainly wetland specialist species, e.g. Reed Bunting Emberiza schoeniclus and species with restricted ranges e.g. Bluethroat Luscinia svecica namnetum). Our results suggest that conservation plans in such geometrical and human-dominated habitats should not only focus on one aspect of landscape characteristics or one aspect of biological diversity but also consider the adverse effects of landscape characteristics on these different facets.; [Krajobrazy o bardzo uproszczonej strukturze charakteryzują się niską różnorodnością taksonomiczną i funkcjonalną ptaków, ale przyciągają gatunki rzadkie]Działalność człowieka może prowadzić do upraszczania krajobrazu i nadawania mu struktury geometrycznej, tj. zbudowanej z prostoliniowychi powtarzalnych jednostek (np. pola uprawne). Podczas gdy rozmieszczenie ptaków w różnych krajobrazach jest często badane, znacznie mniej uwagi poświęca się znaczeniu samej konfiguracji krajobrazu i jego struktury. Jako strukturę należy rozumieć relatywną reprezentację różnych środowisk w danym krajobrazie, zaś konfiguracja to ich przestrzenne ułożenie oraz geometria poszczególnych płatów. W pracy badano wpływ tych dwóch komponentówkrajobrazu — tj. struktury i konfiguracji na trzy różne aspekty zgrupowań ptaków: ich charakterystykę taksonomiczną i funkcjonalną, oraz obecność rzadkich gatunków. Badania prowadzono na terenie czterech salin — obszarów, na których pozyskuje się sól poprzez odparowanie wody z solanki pochodzącej zmorza (Fig. 1). Wybór takiego typu krajobrazu wynikał z faktu, że na tych zmienionych przez człowieka terenach każda jednostka krajobrazujest łatwa do zdefiniowania i opisania, a także dlatego, że struktura tego typu krajobrazu nie ulegała zmianom przez stulecia, w związku zczym badane zależności pomiędzy cechami krajobrazu i bioróżnorodnością nie mogą być tłumaczone przez zmiany które zaszły w ostatnimczasie. Dla każdego z terenów opisywano 12 różnych środowisk (Tab. 1, Apendyks 1). Zgrupowania ptaków zostały scharakteryzo - wane na podstawie liczeń punktowych (łącznie 172 punkty). W analizach uwzględniono wyłącznie gatunki dzienne związane ze środowiskami lądowymi. Dla każdego z punktów, w których liczone były ptaki, obliczono następu jące wskaźniki — dla struktury krajobrazu: całkowitą powierzchnię obszarów lądowych (TA), ogactwo środowisk (liczba różnych środowisk, LR), różnorodność środowisk (na podstawie wskaźnika Shannona, LD); dla konfiguracji krajobrazu— liczbę płatów środowisk lądowych (PU), kształt płatów (PS) oraz zwartość płatów (CO) (Tab. 2). Zgrupowania ptaków opisano za pomocą:liczebności, bogactwa gatunkowego i różnorodności gatunkowej oraz udziału gatun ków rzadkich i pospolitych. Dodatkowo określo noróżnorodność funkcjonalną na podstawie trzech wskaźników: bogactwa (FRic), równomier ności (FEve) i dywergencji (FDiv). Do analizy różnorodności funkcjonalnej wzięto pod uwagę 21 cech historii życia stwierdzonych gatunków ptaków (Apendyks 2). We wszystkich liczeniach punktowych stwierdzono łącznie 69 gatunków ptaków (Apendyks 3). Struktura krajobrazu miała znacz nie silniejszy wpływ na zgrupowania ptaków niż jego konfiguracja (Fig. 2). Nie stwierdzono natomiast wpływu powierzchni badań (Fig. 2). Krajobrazy najbardziej nieprzyja zne — z małą powierzchnią terenów lądowych, niskim bogactwem i różnorodnością środowisk oraz niską zwartością płatów, oraz środowiska bardzo pofragmen to wane ze złożonym układem płatów, charaktery zowały się najniższym bogactwem gatunkowym, różnoro dnością taksonomiczną i funkcjonalną. W śro do wiskach tych występowały jednak gatunkirzadkie — przystosowane do życia w środowiskach podmokłych (jak potrzos) czy takie, mające ograniczone zasięgi (jak podróżniczek).

Landscape composition and physiognomy affect community structure and species distribution across space and time. The pine processionary moth (PPM) (Thaumetopoea pityocampa Den. & Schiff., Lepidoptera, Notodontidae) is a common pine defoliator throughout southern Europe and Mediterranean countries. We surveyed the spatiotemporal distribution of the PPM in a pine plantation forest in southwestern France and used the density of the winter nests as a proxy for population density. The study spanned 4 years (2005–2008) and showed a high temporal variability in nest density. We found a strong edge effect with nest densities at stand edges more than twice as large as within-stand densities. At the landscape scale, the spatial distribution of the moth exhibited a significant spatial autocorrelation in 3 out of 4 years of our study. The spatial scales of the autocorrelation ranged from ca. 2 km to more than 22 km. We found a positive correlation between spatial distributions corresponding to certain sampling years, but the relationship was not systematic. Landscape configuration appeared to be an important driver of the PPM spatial pattern. Bivariate Moran’s I correlograms showed that patch richness density as well as the percentage of local landscape covered by various land uses were correlated with population density. The study showed that accounting for landscape characteristics may be important in order to understand forest insect pest distribution, even in cases where the host species is abundant and homogeneously distributed throughout the study area, e.g., pure plantation forests.

International audience; Vole demographics are often modified close to wooded environments. Population monitoring in such settings reveals substantial edge effects, although these have seldom been quantified. This study compares the abundance of common vole Microtus arvalis (Pallas, 1778) populations at various distances from three types of wooded environment (hedgerow, copse and forest) and in two types of habitat (temporary and permanent grassland). In temporary grassland, substantial edge effects were detected along the boundaries of forests and hedgerows. At 100 m from the forest edge, voles were twice more abundant than at 50 m, four times more than at 25 m and eight times more than at 5 m. In permanent grassland, the edge effect was such that voles were practically absent up to 100 m from the forest edge. For both types of grassland, the edge effect was more pronounced for forest habitat than for hedgerows, that is, for elements with a large surface area of wooded environment. Our results suggest that landscape context may greatly affect the local abundance of voles. Given the considerable damage done by M. arvalis, the presence of wooded patches in grassland areas leads to lower vole densities in adjacent areas and this might be an alternative method to control M. arvalis as a pest species.

International audience; Recent studies suggest that weed seed predation by carabid beetles may partly substitute for chemical weed control in agriculture. Promoting this weed regulation service would require enhancement of the in-field abundance of seed-eating carabids, yet, the diversity of the habitat, trophic requirements and spatial scales of response of different species are complex and our understanding of how management at different spatial scales affects the abundance of seed-eating carabids is limited. Using data collected in 161 arable fields and four crop types across the UK, the factors affecting the abundance of nine common seed feeding carabid species at three spatial scales (local, neighboring, landscape) were investigated using GLMMs. Locally, crop type strongly affected the abundance of individual species, in a species-specific manner and the intensity of field management had a negative effect on the abundance of several species, irrespective of their trophic guild. The occurrence of oilseed rape and grasslands in the neighborhood was found to decrease the abundance of generalist seed-eating carabids but was the main factor positively affecting the abundance of the mainly granivorous Amara aenea, which occur almost exclusively in our sampled oilseed rape fields. At the landscape scale, a generally positive effect of the cover of grassland and oilseed rape demonstrated that in-field carabid abundance responds to the spatial distribution of agricultural land-use in the wider landscape. These findings suggest that management options could be implemented at multiple spatial scales to promote weed seed predation in arable fields.