Landcover data

For each site, we measured surrounding landcover data at multiple spatial scales using QGIS (v 3.30.3, QGIS Development Team). Landcover data was downloaded from the UKCEH Land Cover Map for 2021 at 10 m x 10 m spatial resolution (Marston et al., 2022). Buffer zones around each site were established at radii of 250 m, 500 m, 750 m, and 1000 m, representing the common dispersal and foraging distances of pollinator groups analysed in this study (Bates et al., 2011).Marston, C., Rowland, C.S., O’Neil, A.W., Morton, R.D. (2022) Land Cover Map 2021 (10m classified pixels, GB). NERC EDS Environmental Information Data Centre.26th July 2023.Bates, A.J., Sadler, J.P., Fairbrass, A.J., Falk, S.J., Hale, J.D. and Matthews, T.J. (2011) Changing bee and hoverfly pollinator assemblages along an urban-rural gradient. <i>PloS one</i>, <b>6</b>, e23459.针对每个样点，本研究借助QGIS（v3.30.3，QGIS开发团队）在多种空间尺度下对其周边土地覆被数据进行提取与测算。土地覆被数据源自2021年英国生态与水文中心（UK Centre for Ecology & Hydrology, UKCEH）土地覆被图，空间分辨率为10米×10米（Marston等，2022）。本研究为每个样点设置了半径分别为250米、500米、750米及1000米的缓冲区，这些尺度对应本研究分析的各类传粉昆虫类群典型的扩散与觅食距离（Bates等，2011）。 Marston, C., Rowland, C.S., O’Neil, A.W., Morton, R.D.（2022）《2021年土地覆被图（英国10米分辨率分类像素）》，NERC环境数据服务中心环境信息数据中心，2023年7月26日。 Bates, A.J., Sadler, J.P., Fairbrass, A.J., Falk, S.J., Hale, J.D. 与Matthews, T.J.（2011）沿城乡梯度分布的蜜蜂与食蚜蝇传粉类群组成变化，*PLoS ONE*，第6卷，e23459。