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. 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. 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. Synthesis and applications. We show that the joint effort of preserving semi‐natural habitats and promoting crop diversity in agricultural landscapes is necessary to enhance communities of natural enemies and pollinators. Our results suggest that increasing the diversity of crop types can contribute to the conservation of service‐providing arthropod communities, particularly if the diversification of crops targets complex landscapes with a high proportion of semi‐natural habitats.

Loss and fragmentation of semi-natural grasslands have had negative consequences for grassland biodiversity, such as butterflies. Urban parks and other urban green spaces have so far largely been overlooked as suitable butterfly habitats, although they could potentially sustain diverse butterfly populations over time. We analysed the temporal change in butterfly species assemblages in urban green spaces in the city of Malmö, Southern Sweden. We studied changes in species richness and abundance of butterflies between 2006 and 2015 in 20 public urban green spaces, characterized by different management regimes. We sampled butterflies in traditional parks with intense grass cutting regimes, in semi-natural grasslands mowed only a few times per year, and in un-managed or irregularly managed ruderal sites. We found a slight increase in the total number of butterfly species in the study area, but a general decline in local species numbers in urban green spaces. Traditional urban parks had the greatest loss of species over time, and altogether the lowest number of species. In contrast, semi-natural parks and ruderal sites had higher numbers of butterfly species and also lost fewer species over time. Our study shows that intensive management strategies in urban green spaces have a negative impact on butterfly assemblages over time. We suggest that less intensive management strategies can be used to create high-quality areas for flower-visiting insects in urban green spaces, possibly in combination with planting larval host plant species, depending on the park type and design.

Biological control by natural enemies is a valuable ecosystem service. The predator community in a crop field is a combination of predators dwelling in the field and those moving into it from the surrounding landscape. The former is mainly affected by field management, the latter more by the composition of the surrounding landscape. Yet, separate and combined effects of local and landscape management on pest suppression have seldom been investigated. We set‐up mesocosms within an existing long‐term agricultural field experiment to investigate the effects of local management of organic manure or inorganic mineral fertilisation, and simulated the spillover from the surrounding landscape of different predator types: no predators, generalist predators (wolf spiders) and specialist predators (ladybirds). We examined whether aphid density was driven by top‐down or bottom‐up processes under different fertilisation treatments, and how the magnitude of pest suppression was affected by predator community composition. We found positive synergistic effects between manure fertilisation and predator spillover on the suppression of aphid growth. Top‐down suppression of aphids was more effective under manure fertilisation and in presence of specialist predators (ladybirds). Bottom‐up effects on the plant biomass growth dominated in inorganically fertilised plots. Organic and inorganic fertilisation gave the same yield, but through different mechanisms. The abundance of locally emerging predators in the manure treatment increased top‐down pest suppression yielding plant biomass levels comparable with inorganically fertilised plants, being the latter driven by bottom‐up effects. Synthesis and applications. Organic fertilisation enhanced local emergence of predators increasing top‐down pest suppression. In contrast, local predator communities were unable to suppress aphid populations in inorganic and no fertilisation treatments. Here, predator inflow from outside the crop field was essential for lowering aphid population growth. Managing landscapes to promote mobile predators emerges as particularly important for crop fields without manure amendments. We advise the active promotion of both local predators in the crop field and mobile predators in the landscape to secure the conservation of biological insect pest suppression.

Managing agricultural landscapes integrate production, biodiversity conservation and the flow of ecosystem services (ES) is of paramount importance to simultaneously meet production goals and environmental challenges. However, the response of farmland biodiversity and multiple ES to land‐use change at multiple spatial scales remains poorly understood. We explored the effects of land‐use at local (grassland vs. oilseed rape fields) and landscape scale (cover of permanent grasslands) on the provision of biodiversity (plants, arthropods, birds), five ES (pollination, pest control, soil fertility, carbon storage and water regulation) and overall ES‐multifunctionality. ES‐multifunctionality was higher in grasslands than in crop fields, by 25.2% above‐ground and by 106.1% below‐ground. Multiple threshold analyses highlighted a particularly poor level of performance for below‐ground functions in crop fields. This habitat type was however capable of providing numerous above‐ground functions simultaneously, although at low levels of performance when compared to the maximum values recorded in the study. Grasslands supported higher biodiversity and provision of pollination, soil fertility, carbon storage and water regulation. Landscape composition influenced the provision of multiple ES: a 10% increase in grassland cover in the landscape enhanced above‐ground ES‐multifunctionality by 11.0% in both habitats. In particular, grasslands cover in the landscape supported the provision of arthropod diversity, pollination and pest control provided by carabids. Synthesis and applications. The results of this field study show the key importance of preserving semi‐natural grasslands in agricultural landscapes for the conservation of farmland biodiversity, for the protection of soils and the delivery of multiple ES critical for crop production. Maximization of multifunctionality necessitates the integration at the landscape scale (0.5–2 km) of semi‐natural patches within the intensively farmed agricultural matrix. This would require not only the protection of existing grasslands, but also their restoration in simplified landscapes. The promotion of mixed farming (i.e., both crop and livestock production) might increase semi‐natural grassland cover at the landscape scale.

Pollinators benefit from increasing floral resources in agricultural landscapes, which could be an underexplored co‐benefit of mass‐flowering crop cultivation. However, the impacts of mass‐flowering crops on pollinator communities are complex and appear to be context‐dependent, mediated by factors such as crop flowering time and the availability of other flower resources in the landscape. A synthesis of research is needed to develop management recommendations for effective pollinator conservation in agroecosystems. By combining 22 datasets from 13 publications conducted in nine temperate countries (20 European, 2 North American), we investigated if mass‐flowering crop flowering time (early or late season), bloom state (during or after crop flowering) and extent of non‐crop habitat cover in the landscape moderated the effect of mass‐flowering crop cover on wild pollinator abundance and species richness in mass‐flowering crop and non‐crop habitats. During bloom, wild bee abundance and richness are negatively related to mass‐flowering crop cover. Dilution effects were predominant in crop habitats and early in the season, except for bumblebees, which declined with mass‐flowering crop cover irrespective of habitat or season. Late in the season and in non‐crop habitats, several of these negative relationships were either absent or reversed. Late‐season mass‐flowering crop cover is positively related to honeybee abundance in crop habitats and to other bee abundance in non‐crop habitats. These results indicate that crop‐adapted species, like honeybees, move to forage and concentrate on late‐season mass‐flowering crops at a time when flower availability in the landscape is limited, potentially alleviating competition for flower resources in non‐crop habitats. We found no evidence of pollinators moving from mass‐flowering crop to non‐crop habitats after crop bloom. Synthesis and applications: Our results confirm that increasing early‐season mass‐flowering crop cover dilutes wild pollinators in crop habitats during bloom. We find that dilution effects were absent late in the season. While mass‐flowering crop cultivation alone is unlikely to be sufficient for maintaining pollinators, as part of carefully designed diverse crop rotations or mixtures combined with the preservation of permanent non‐crop habitats, it might provide valuable supplementary food resources for pollinators in temperate agroecosystems, particularly later in the season when alternative flower resources are scarce.

Pest management is essential to maintain agricultural production, but recent shifts in policies and the development of insecticide resistance have restricted the availability of insecticides for pest suppression. Identifying the landscape‐level resource requirements of pests to complete their life cycles might unveil new sustainable solutions to regulate their populations and prevent crop damage. We assessed the effects of landscape composition and configuration at different spatial scales on flea beetle densities and crop damage in 56 spring oilseed rape fields sampled over 5 years in Sweden. We considered the cover of non‐crop habitats as an aspect of landscape composition and the distances to the host crop and an alternative host crop in the previous year, edge density and crop diversity as aspects of landscape configuration. The distance from spring oilseed rape in the previous year reduced flea beetle densities and crop damage across most species and spatial scales. Edge density reduced the densities of two flea beetle species, predominantly at the 500 m radius landscape scale. The cover of forests and permanent pastures as well as crop diversity in the previous year increased the densities of different species at several, mostly larger (1000–2000 m) spatial scales. Increasing permanent pasture cover at the 500 m scale also increased crop damage. Synthesis and applications: We find that there is no one fits all approach in designing landscapes for flea beetle regulation as habitat use and scales of effect are species‐specific for these pests. However, increasing the spatiotemporal isolation of host crop fields is a promising and potentially more general means of disrupting pest populations and reducing crop damage. Considering the ecological traits of the pest species is a possible next step to optimise landscape‐based pest management.