Quistberg Robyn D, Bichier Peter, Philpott Stacy M
1Environmental Studies Department, University of California, Santa Cruz, 1156 High St., Santa Cruz, CA 95064 (
2Ecology and Evolutionary Biology Department, University of California, Santa Cruz, 1156 High St., Santa Cruz, CA 95064, and.
Environ Entomol. 2016 Jun 1;45(3):592-601. doi: 10.1093/ee/nvw025.
Urban gardens may preserve biodiversity as urban population densities increase, but this strongly depends on the characteristics of the gardens and the landscapes in which they are embedded. We investigated whether local and landscape characteristics are important correlates of bee (Hymenoptera: Apiformes) abundance and species richness in urban community gardens. We worked in 19 gardens in the California central coast and sampled bees with aerial nets and pan traps. We measured local characteristics (i.e., vegetation and ground cover) and used the USGS National Land Cover Database to classify the landscape surrounding our garden study sites at 2 km scales. We classified bees according to nesting type (i.e., cavity, ground) and body size and determined which local and landscape characteristics correlate with bee community characteristics. We found 55 bee species. One landscape and several local factors correlated with differences in bee abundance and richness for all bees, cavity-nesting bees, ground-nesting bees, and different sized bees. Generally, bees were more abundant and species rich in bigger gardens, in gardens with higher floral abundance, less mulch cover, more bare ground, and with more grass. Medium bees were less abundant in sites surrounded by more medium intensity developed land within 2 km. The fact that local factors were generally more important drivers of bee abundance and richness indicates a potential for gardeners to promote bee conservation by altering local management practices. In particular, increasing floral abundance, decreasing use of mulch, and providing bare ground may promote bees in urban gardens.
随着城市人口密度的增加，城市花园可能会保护生物多样性，但这在很大程度上取决于花园的特征以及它们所处的景观环境。我们调查了当地和景观特征是否是城市社区花园中蜜蜂（膜翅目：蜜蜂科）数量和物种丰富度的重要相关因素。我们在加利福尼亚州中部海岸的19个花园中开展研究，并用空中网和诱虫盘对蜜蜂进行采样。我们测量了当地特征（即植被和地被植物），并使用美国地质调查局的国家土地覆盖数据库对我们花园研究地点周围2公里范围内的景观进行分类。我们根据筑巢类型（即洞穴、地面）和体型对蜜蜂进行分类，并确定哪些当地和景观特征与蜜蜂群落特征相关。我们发现了55种蜜蜂。一种景观因素和几个当地因素与所有蜜蜂、洞穴筑巢蜜蜂、地面筑巢蜜蜂以及不同体型蜜蜂的数量和丰富度差异相关。一般来说，在更大的花园、花卉丰富度更高、覆盖物更少、裸地更多且草地更多的花园中，蜜蜂数量更多且物种更丰富。在2公里范围内被更多中等强度开发土地环绕的地点，中型蜜蜂数量较少。当地因素通常是蜜蜂数量和丰富度的更重要驱动因素，这一事实表明园丁有可能通过改变当地管理做法来促进蜜蜂保护。特别是，增加花卉丰富度、减少覆盖物使用以及提供裸地可能会促进城市花园中的蜜蜂数量增加。
