Dissertation Research: Drivers of community composition, species interactions, and gene flow in urban landscapes

论文研究：城市景观中群落组成、物种相互作用和基因流动的驱动因素

• 批准号: 1701469
• 负责人: Shalene Jha
• 金额: $ 2.03万
• 依托单位: University of Texas at Austin
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1701469&HistoricalAwards=false
• 关键词: Dissertation; Research; Drivers; community; composition

Animals contribute to the pollination of 90% of all plant species; therefore they are essential for maintaining healthy ecosystems. Of these animals, bees are some of the most effective and important pollinators of wild plants and their service as pollinators to agricultural systems is worth hundreds of billions of dollars each year. In addition to the familiar domesticated European honeybee, there are at least 20,000 other species of wild bees worldwide. Many of these wild bee populations, however, are declining in number due to human-caused landscape changes, including urbanization. This research explores how urban landscapes alter the types of bee species found in cities, how urban bees use and pollinate native plants, and how different-sized bee species move through urban areas. As a part of this project, researchers will make recommendations to land owners to promote healthy pollinator communities. In addition, this project will enrich the scientific community by employing college and high school students from underserved communities as research assistants. The study will investigate the impacts of urban land use patterns on plant-pollinator interactions using a network analysis approach. The plant-pollinator networks across an urban gradient will be developed through observations of floral visits by bees and the examination of pollen diversity collected from bees found along a gradient of urbanization (40 sites ranging in urban coverage from 0-100 %). As previous observations indicate that urbanized areas contain fewer food resources than rural areas, the researchers predict that bees at urban sites may visit a greater variety of floral species, whereas bees in rural sites may be more specialized in their food choices. To investigate dispersal and colonization patterns within urban landscapes, this study will also examine the genetic make-up of two closely related carpenter bee species. These species are similar in nesting behavior, but vary in size and thus their dispersal potential. The researchers predict that the larger species (Xylocopa virginica) will show fewer genetic signatures of population isolation (ex. inbreeding) than the smaller species (Ceratina strenua) because they can disperse farther through urban areas. Ultimately, results from this study will allow inferences on how pollinators can persist in urban landscapes over time.

动物为90%的植物授粉，因此它们对维持健康的生态系统至关重要。 在这些动物中，蜜蜂是野生植物最有效和最重要的授粉者，它们作为授粉者为农业系统提供的服务每年价值数千亿美元。 除了常见的欧洲蜜蜂外，世界上还有至少20，000种其他野生蜜蜂。然而，由于人类引起的景观变化，包括城市化，许多野生蜜蜂种群数量正在下降。这项研究探讨了城市景观如何改变城市中发现的蜜蜂物种的类型，城市蜜蜂如何使用和授粉本地植物，以及不同大小的蜜蜂物种如何在城市地区移动。作为该项目的一部分，研究人员将向土地所有者提出建议，以促进健康的传粉者社区。此外，该项目还将通过雇用来自服务不足社区的大学生和高中生担任研究助理来丰富科学界。该研究将采用网络分析方法调查城市土地利用模式对植物-传粉者相互作用的影响。将通过观察蜜蜂的访花和检查从沿着城市化梯度（40个地点，城市覆盖率从0- 100%不等）发现的蜜蜂收集的花粉多样性，开发城市梯度上的植物-传粉者网络。由于先前的观察表明，城市化地区的食物资源比农村地区少，研究人员预测，城市地区的蜜蜂可能会访问更多种类的花卉物种，而农村地区的蜜蜂可能在食物选择上更专业。为了研究城市景观中的传播和殖民模式，本研究还将研究两种密切相关的木蜂物种的遗传组成。这些物种在筑巢行为上相似，但大小不同，因此它们的扩散潜力也不同。 研究人员预测，较大的物种（Xylocopa virginica）将显示出较少的种群隔离遗传特征（例如，近亲繁殖）比较小的物种（Ceratina strenua），因为它们可以通过城市地区传播得更远。最终，这项研究的结果将允许推断传粉者如何随着时间的推移在城市景观中持续存在。