Database of plant-flower visitor interactions from Ireland

Beneficial insects provide valuable services upon which we rely, including
pollination. Pollinator conservation is a global priority, and a
significant concern in Ireland, where over half of extant bee species have
declined significantly in recent decades. As flower-visiting insects rely
on flowering plants, one way to conserve and promote pollinator
populations is to protect high-quality habitat. We analysed the structure
of insect-flower interactions from multiple habitat categories in a large
database of interactions from Ireland. Our primary goals were to compare
spatial and temporal variation in Irish network structures, compare Irish
networks to published networks from other countries, and provide
evidence-based recommendations for pollinator conservation in Ireland by
identifying well-visited plant species that may promote high pollinator
diversity, abundance, and functional complementarity. Habitat types within
Ireland differed substantially: semi-natural grasslands had the highest
pollinator species richness and largest number of unique pollinator
species, while intensively-managed habitats exhibited negative asymmetry
(more plant than pollinator species). This negative asymmetry is notable
because most plant-pollinator networks exhibit a positive asymmetry.
Within intensively-managed habitats, agricultural and urban habitats
differed. Urban habitats had the highest number of non-native plant
species while agricultural habitats had the lowest pollinator species
richness. We also found Irish networks varied across the growing season,
where July had the highest plant and insect species richness. When
comparing Irish networks to published networks from other countries, we
found Irish networks had a higher ratio of plant species to pollinator
species, and that this difference was most evident in agricultural
habitats. This ratio means the typical network asymmetry (more pollinator
than plant species) was flipped (more plant than pollinator species) in
the Irish network. We conclude that conserving semi-natural grasslands in
Ireland will be an essential component of pollinator conservation and
identify thirty-five plant species important for restoring semi-natural
habitats.

益虫可为人类提供赖以生存的宝贵生态服务，其中便包含授粉（pollination）服务。授粉昆虫保护是全球优先推进的生态议题，在爱尔兰同样备受重视——近几十年来，该国现存蜂类物种中有逾半数已出现显著衰退。由于访花昆虫依赖显花植物生存，保护并促进授粉昆虫种群的关键途径之一，便是守护高质量栖息生境。我们对爱尔兰境内大型昆虫-植物互作数据库中不同生境类群的互作网络结构开展了系统性分析。本研究的核心目标包括三方面：其一，对比爱尔兰境内授粉网络的空间与时间变异特征；其二，将爱尔兰的互作网络与其他国家已发表的同类网络进行对比分析；其三，通过筛选可有效提升授粉昆虫多样性、种群丰度及功能互补性的、频繁被授粉昆虫访问的植物物种，为爱尔兰的授粉昆虫保护工作提供循证决策建议。爱尔兰境内的生境类型差异显著：半自然草地的授粉昆虫物种丰富度最高，特有授粉昆虫物种数量也最多；而集约化管理生境则呈现负不对称性特征，即植物物种数多于授粉昆虫物种数。这一负不对称性特征值得关注，因为绝大多数已报道的植物-授粉昆虫互作网络通常表现为正不对称性。在集约化管理生境中，农业生境与城市生境亦存在明显差异：城市生境的外来植物物种占比最高，而农业生境的授粉昆虫物种丰富度最低。此外，我们还发现爱尔兰的互作网络随生长季呈现动态变化，其中7月的植物与昆虫物种丰富度均达到峰值。将爱尔兰的互作网络与其他国家已发表的同类网络进行对比后发现，爱尔兰网络的植物物种与授粉昆虫物种的比例更高，且这一差异在农业生境中表现得最为突出。该比例反转了典型植物-授粉昆虫互作网络的不对称性特征：常规网络通常表现为授粉昆虫物种数多于植物物种数，而爱尔兰网络则呈现出植物物种数多于授粉昆虫物种数的反转态势。本研究最终得出结论：保护爱尔兰境内的半自然草地是推进授粉昆虫保护工作的核心举措，并筛选出35种对恢复半自然栖息生境具有重要价值的植物物种。