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Pollinators experience large spatiotemporal fluctuations in resource availability when mass-flowering crops are rotated with resource-poor cereal crops. Yet, few studies have considered the effect this has on pollinator population stability, nor how this might be mitigated to maintain consistent crop pollination services. We assess the potential of boundary features (standard narrow 1 m grassy margins, hedgerows and wide 4 m agri-environment margins) to support and stabilise pollinator populations and pollination service in agricultural landscapes under crop rotation. Assuming a 6-year rotation, we use a process-based pollinator model to predict yearly pollinator population size and in-crop visitation rates to oilseed rape and field bean across 117 study landscapes in England with varying amounts of boundary features. We model both ground-nesting bumblebees and solitary bees and compare the predictions including and excluding boundary features from the landscapes. Ground-nesting bumblebee populations, whose longer-lifetime colonies benefit from continuity of resources, were larger and more stable (relative to the no-features scenario) in landscapes with more boundary features. Ground-nesting solitary bee populations were also larger but not significantly more stable, except with the introduction of wide permanent agri-environment margins, due to their shorter lifetimes and shorter foraging/dispersal ranges. Crop visitation by ground-nesting bumblebees was greater and more stable in landscapes with more boundary features, partly due to increased colony growth prior to crop flowering. Time averaged crop visitation by ground-nesting solitary bees was slightly lower, due to females dividing their foraging time between boundary features and the crop. However, despite this, the minimum pollination service delivered was higher, due to the more stable delivery. Synthesis and applications. Field boundary features have an important role in stabilising pollinator populations a

To address the decline in farmland birds across agricultural landscapes a key approach under agri-environment schemes has been the widespread creation of perennial grass-only buffer strips along field boundaries. However, despite a high dependency on these strips to enhance biodiversity in agricultural landscapes, it appears that benefits for farmland birds during the breeding season have been limited. We investigated the provision of plant and invertebrate resources for farmland birds in buffer strips that were established with three different seed mixes, including the standard grass-only habitat. We hypothesised that resource provision would differ between seed mix types due to differences in original composition. We also investigated three different types of management aimed at influencing sward composition and habitat structure, namely cutting, scarification and the application of graminicide. These approaches were used to influence the accessibility of structurally complex swards to farmland birds. We hypothesised that the abundance of plant and invertebrate resources and access to these resources would be directly related to management type. The abundance of plant resources and sward structure were determined using quadrats and the drop disc method respectively, whilst the invertebrates were assessed using suction sampling. The study demonstrated the value of including forbs (herbaceous plant species) in seed mixes used to establish buffer strips by increasing plant resources for farmland birds, although this was not coupled with an increase in beetle abundance and mass. However, grass-only buffer strips managed with annual cutting were shown to provide similar levels of invertebrate resources to farmland birds as with the more complex seed mixes, but it is likely that access to these resources was restricted by tall homogenous swards and a limited amount of bare ground. The study demonstrated that novel buffer strip management techniques can strongly influenc