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Agricultural intensification is a leading cause of global biodiversity loss, which can reduce the provisioning of ecosystem services in managed ecosystems. Organic farming and plant diversification are farm management schemes that may mitigate potential ecological harm by increasing species richness and boosting related ecosystem services to agroecosystems. What remains unclear is the extent to which farm management schemes affect biodiversity components other than species richness, and whether impacts differ across spatial scales and landscape contexts. Using a global metadataset, we quantified the effects of organic farming and plant diversification on abundance, local diversity (communities within fields), and regional diversity (communities across fields) of arthropod pollinators, predators, herbivores, and detritivores. Both organic farming and higher in‐field plant diversity enhanced arthropod abundance, particularly for rare taxa. This resulted in increased richness but decreased evenness. While these responses were stronger at local relative to regional scales, richness and abundance increased at both scales, and richness on farms embedded in complex relative to simple landscapes. Overall, both organic farming and in‐field plant diversification exerted the strongest effects on pollinators and predators, suggesting these management schemes can facilitate ecosystem service providers without augmenting herbivore (pest) populations. Our results suggest that organic farming and plant diversification promote diverse arthropod metacommunities that may provide temporal and spatial stability of ecosystem service provisioning. Conserving diverse plant and arthropod communities in farming systems therefore requires sustainable practices that operate both within fields and across landscapes., EML and DC were supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, under award number 2014‐51106‐22096. BMF was supported by the National Council for Scientific and Technological Development‐CNPq, Brasília, Brazil #305062/2007‐7. SGP and MO were supported by the Felix Trust and STEP Project (EC FP7 244090).

1. Habitat fragmentation is thought to threaten biodiversity, but the response of pollinators to fragmentation is still poorly understood, and research seldom includes pollinator nesting requirements. 2. We investigated pollinator community composition in a highly fragmented oak-savannah ecosystem in south-western British Columbia, Canada. We sampled pollinators in 19 fragments ranging from 0.3 to 31 ha and surrounded by a variety of land-use types, including forest, low-density suburban, and urban neighbourhoods. Pan-trapping and netting surveys captured 4464 bees, flies, and wasps in 138 species and 48 genera. 3. Contrary to expectations, overall species richness did not increase with fragment size. However, ground-nester abundance (not diversity) and cavity-nester diversity (not abundance) were higher in larger fragments, as expected. Floral richness and abundance did not foster pollinator diversity for either guild. Brood parasite responses were complex: host availability (ground-nesting bees) was generally important, richness and abundance increased in fragments with high surrounding road density, and abundance also increased in fragments with other habitat fragments nearby. 4. Responses of different nesting guilds to fragmentation may be related to their use of the landscape surrounding habitat fragments. Some common cavity nesters can nest in fences and gardens, but urban land use may be less hospitable for ground nesters. Brood parasites apparently respond both to host availability and landscape characteristics associated with movement among fragments. 5. Consideration of nesting requirements of pollinators provided some insight into their response to habitat loss in our analysis and should be considered in future studies of fragmentation impacts on pollinator biodiversity.

Bees provide essential pollination services that are potentially affected both by local farm management and the surrounding landscape. To better understand these different factors, we modelled the relative effects of landscape composition (nesting and floral resources within foraging distances), landscape configuration (patch shape, interpatch connectivity and habitat aggregation) and farm management (organic vs. conventional and local-scale field diversity), and their interactions, on wild bee abundance and richness for 39 crop systems globally. Bee abundance and richness were higher in diversified and organic fields and in landscapes comprising more high-quality habitats; bee richness on conventional fields with low diversity benefited most from high-quality surrounding land cover. Landscape configuration effects were weak. Bee responses varied slightly by biome. Our synthesis reveals that pollinator persistence will depend on both the maintenance of high-quality habitats around farms and on local management practices that may offset impacts of intensive monoculture agriculture. Bees provide essential pollination services that are potentially affected both by local farm management and the surrounding landscape. To better understand these different factors, we modelled the relative effects of landscape composition (nesting and floral resources within foraging distances), landscape configuration (patch shape, interpatch connectivity and habitat aggregation) and farm management (organic vs. conventional and local-scale field diversity), and their interactions, on wild bee abundance and richness for 39 cropsystems globally. Bee abundance and richness were higher in diversified and organic fields and in landscapes comprising more high-quality habitats; bee richness on conventional fields with low diversity benefited most from high-quality surrounding land cover. Landscape configuration effects were weak. Beeresponses varied slightly by biome. Our synthesis reveals that pollinator persistence will depend on boththe maintenance of high-quality habitats around farms and on local management practices that may offsetimpacts of intensive monoculture agriculture.