Larson Diane L, Simanonok Michael, Landsman Andrew, Larson Jennifer L, Davies Cora, Otto Clint R V
U.S. Geological Survey Northern Prairie Wildlife Research Center Jamestown North Dakota USA.
National Park Service Chesapeake & Ohio Canal National Historical Park - CHOH Williamsport Maryland USA.
Ecol Evol. 2024 Dec 17;14(12):e70719. doi: 10.1002/ece3.70719. eCollection 2024 Dec.
National Park Service units in the United States play a large role in providing habitat for native pollinators. In parks that are established to preserve cultural landscapes, park managers recognize an opportunity to improve pollinator habitat while maintaining historically accurate conditions. In this study, we document floral resources and native bees within managed park grasslands, with the goal of providing information to managers to help them maximize pollinator habitat while meeting other management objectives. The study was performed on 37 grassland properties in the mid-Atlantic region of the eastern United States, distributed across four parks; each property was managed with one of three management types: cool-season hayed, cool-season pasture, or warm-season meadows managed with multiple approaches. We surveyed bees and open flowers on 50-m transects twice each year in 2021 and 2022. Repeated-measures ANOVA models revealed that mean bee abundance, richness, evenness, and diversity did not vary among sites or management types. This finding was further supported by a principal coordinates analysis that showed that bee community composition was similar across management types. Nonetheless, we found evidence to indicate that the three management types did not produce equivalent habitat for bees. Species accumulation curves showed that the effective number of flower species was consistently lower in cool-season pastures, relative to the other two management types. Furthermore, we detected positive correlations between bee and flower diversity metrics in one of the 2 years, indicating that floral metrics are associated with bee communities, at least under certain conditions. Collectively, our study suggests that cool-season fields that are hayed and warm-season meadows have higher floral diversity than cool-season pastures within national park units of the mid-Atlantic region, and this higher diversity of forbs has the potential to benefit native bee diversity.
美国国家公园管理局的各单位在为本土传粉者提供栖息地方面发挥着重要作用。在那些为保护文化景观而设立的公园中，公园管理者认识到在维持历史准确风貌的同时改善传粉者栖息地的机会。在本研究中，我们记录了管理的公园草地内的花卉资源和本土蜜蜂，目的是向管理者提供信息，帮助他们在实现其他管理目标的同时最大限度地增加传粉者栖息地。该研究在美国东部中大西洋地区的37处草地进行，分布在四个公园；每个地块采用三种管理类型之一进行管理：冷季割草、冷季放牧或采用多种方法管理的暖季草地。我们在2021年和2022年每年两次在50米长的样带上调查蜜蜂和开放花朵。重复测量方差分析模型显示，蜜蜂的平均丰度、丰富度、均匀度和多样性在不同地点或管理类型之间没有差异。主坐标分析进一步支持了这一发现，该分析表明不同管理类型的蜜蜂群落组成相似。尽管如此，我们发现有证据表明这三种管理类型并没有为蜜蜂产生同等的栖息地。物种累积曲线表明，相对于其他两种管理类型，冷季牧场的花卉物种有效数量一直较低。此外，我们在两年中的一年检测到蜜蜂和花卉多样性指标之间存在正相关，表明花卉指标与蜜蜂群落相关，至少在某些条件下是这样。总体而言，我们的研究表明，在中大西洋地区的国家公园单位内，冷季割草地和暖季草地的花卉多样性高于冷季牧场，而这种更高的草本植物多样性有可能使本土蜜蜂多样性受益。
