The role of woodlands in the diversity and resilience of pollinator communities in agricultural landscapes

林地在农业景观中传粉媒介群落多样性和复原力中的作用

• 批准号: 2575921
• 金额: --
• 依托单位: University of East Anglia
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2575921
• 关键词: role; woodlands; diversity; resilience; pollinator

Scientific backgroundIntensive agriculture is a key driver of declines in pollinating insect populations and pollination services. Ecological intensification to mitigate these effects has focused largely on restoring field-scale semi-natural habitat including flower strips and other habitat patches for grassland and wildflowers. The boost to floral resources provided by these agri-environment schemes typically span only a portion of the seasonal activity period for pollinating insect assemblages. Provision of pollination services on farmland is also dependent on wider landscape context, with relatively little attention being paid to the influence of woodland patches upon pollinator communities.Uncertainty remains over which plant species are the most valuable food resources for pollinator species, and how their relative value varies seasonally. While the benefits to bees of grassland-associated wildflowers is well-established, the complementary role of trees and woodland in buffering the provision of pollinator resources (nectar and pollen) is less well-studied in agricultural landscapes. Woodlands can provide among the highest levels of nectar production for a major UK habitat, and the use by pollinating insects of tree species may be disproportionate to the abundance of woodland in the landscape. Woodland tree species composition also influences other plants, with consequences for pollinators. Woodlands and woody corridors (hedgerows) in landscapes provide nesting and larval microsites for a range of pollinator species.Aims and objectivesThis project will investigate the role of woodland in the maintenance and resilience of pollinator insect communities in agricultural landscapes. Sampling of insects will be carried out in a selected study landscape in Norfolk spanning a range of densities of woodland patches and hedgerow networks. The project sets out to address the following key research questions:(1) How similar are pollinator assemblages that occur in woodland canopies compared with those that occur at ground level, in woodland interiors and in more open farmland habitats? We will investigate which pollinator species show the greatest proportional occurrence in woodland canopies relative to more open habitats, and test for correlation between canopy occurrences and availability of either pollen and/or nectar sources in woodland canopies. (2) Are pollinators found in or close to woodland canopies foraging on tree pollen resources? We will use molecular techniques to determine the identity of pollinator insect taxa, and their associated pollen, sampled from woodland canopies and at varying distance from woodland habitat. This work will establish which species of tree pollen, if any, are being used. We will test for circa 20 common woodland tree species, including some wind-pollinated species.(3) Do woodland areas promote seasonal stability in pollinator diversity and abundance in the surrounding landscape? The research design will focus on sampling within significant woodland patches within the study area, and at varying proximities to these patches within agricultural landscapes, including varying distances along hedgerows with and without trees. Repeat sampling in spring and summer will capture seasonal variations in pollinator assemblages. (4) What are the optimal woodland and woody corridor management recommendations for maintaining resilient pollinator communities, hence pollination services, in agricultural landscapes? Here we will focus on the role of woody corridors as linear features in the landscape, and how to optimise their role in connectivity of pollinator assemblages between woodland patches and cultivated landscapes and maintain pollination services.

科学背景集约化农业是授粉昆虫种群和授粉服务下降的关键驱动力。生态强化，以减轻这些影响，主要集中在恢复领域规模的半自然栖息地，包括花带和其他栖息地补丁的草地和野花。这些农业环境计划提供的花卉资源的提升通常只跨越授粉昆虫聚集的季节性活动期的一部分。农田授粉服务的提供也依赖于更广泛的景观背景，相对较少关注林地斑块对传粉昆虫群落的影响，仍然不确定哪些植物物种是传粉昆虫物种最有价值的食物资源，以及它们的相对价值如何随季节变化。虽然草地相关的野花对蜜蜂的好处是众所周知的，但树木和林地在缓冲授粉者资源（花蜜和花粉）提供方面的补充作用在农业景观中研究得较少。林地可以为英国的一个主要栖息地提供最高水平的花蜜生产，并且授粉昆虫对树种的使用可能与景观中林地的丰富程度不成比例。林地树种组成也影响其他植物，对传粉者产生影响。景观中的林地和木质走廊（灌木树篱）为一系列传粉昆虫物种提供了筑巢和幼虫的微生境。Aims and objectivesThis project will investigate the role of woodland in the maintenance and resilience of pollinator insects communities in agricultural landscapes.昆虫采样将在诺福克的一个选定的研究景观中进行，该景观涵盖了林地斑块和绿篱网络的密度范围。该项目旨在解决以下关键研究问题：（1）与发生在地面水平，林地内部和更开放的农田栖息地相比，发生在林地冠层中的传粉者组合有多相似？我们将调查哪些传粉昆虫物种表现出最大的比例发生在林地树冠相对于更开放的栖息地，并测试树冠发生和可用性的花粉和/或花蜜来源在林地树冠之间的相关性。(2)传粉者是否在林地树冠中或附近发现以树木花粉资源为食？我们将使用分子技术来确定传粉昆虫类群的身份，以及它们相关的花粉，从林地树冠和不同距离的林地栖息地采样。这项工作将确定哪些树种的花粉，如果有的话，正在使用。我们将测试大约20种常见的林地树种，包括一些风媒传粉的树种。(3)林地地区是否促进了周围景观中传粉者多样性和丰富度的季节稳定性？研究设计的重点是在研究区域内重要的林地斑块内取样，以及在农业景观内与这些斑块的不同接近程度，包括沿着有树和无树的沿着的不同距离。在春季和夏季重复采样将捕捉传粉者组合的季节性变化。(4)什么是最佳的林地和木本走廊管理的建议，以保持弹性授粉社区，因此授粉服务，在农业景观？在这里，我们将重点关注的作用，木质走廊的线性功能的景观，以及如何优化其作用，在林地斑块和耕地景观之间的传粉者组合的连接，并保持授粉服务。