Pollinator data from transect walks - bees and hoverflies in agroforestry and monoculture systems

Data on bee and hoverfly observations during transect walks, used for the analysis presented in Varah, A., Jones, H., Smith, J., & Potts, S. G. (2020). Temperate agroforestry systems provide greater pollination service than monoculture. Agriculture, Ecosystems & Environment, 301, 107031. https://doi.org/10.1016/j.agee.2020.107031.This data was collected on standardised transect walks between 2011-2013 at six agroforestry sites in the UK. Details of methodology are given in the publication. All farmers gave approval for data collection at their sites.Columns A-AA give details of sites, dates of visits, position on transect, and environmental variables.Columns AB-AP give abundance counts for bees and hoverflies. Bumblebees were recorded at the level of individual species (columns AB-AN), apart from Bombum terrestris and Bombus lucorum which were recorded as one aggregate species. Solitary bees and hoverflies were not identified to species.Where columns of abundance counts have NA values this is because the data for that species or taxon was not used in the analysis. Reasons for exclusions are given in the paper. Full data without exclusions is available on request.Below are details of column names where their content is not immediately obvious:visit - we sequentially numbered visits to each site. At site WAF there is no visit 8 because the data from that visit was not used in the analysis. Reasons for this are given in the paper.jdate - number of days since 1st Marchstarttime / enddime - the start and end of the transect. Where it was necessary to stop to catch and identify a bee, the transect walk was paused. This means that transects are not all of equal time length, although time actually spent walking and searching for pollinators was standardised.landuse - p, pasture; a, arabletreatment - AF, agroforestry; MC, monoculturealleywidth - distance between tree rows, in metersalleylength - the length of tree rows, in metershedg.dist - the shortest distance between the transect and the nearest hedgerowboundSR.all - plant species richness in field boundaries (both hedges and margins)boundSR.ip - the species richness of insect-pollinated plants in field boundaries (both hedges and margins)bound.area - the area covered by the field boundariesn.hedg.bound - the number of hedged field boundariesn.hedg.trees - the number of trees in field boundariessnh - the percentage of semi-natural habitat (SNH) in a 1 km buffer around field perimeterstran.pos - whether that part of the transect was at the edge or the centre of an alleytran.dist - each transect was separated into 25 meter sections, and this variable specifies the sectionsun - the percentage of the transect that was sunny (time estimated during transect)beeact - a subjective indication of how active bees were during the transect ('low', 'medium' or 'high' activity)wind - how windy it was during the transect, using Beaufort scale values

本数据集包含样带行走（Transect Walk）过程中观测到的蜜蜂与食蚜蝇（Hoverfly）相关数据，用于支撑Varah等人2020年发表的分析研究：Varah, A., Jones, H., Smith, J., & Potts, S. G. (2020). Temperate agroforestry systems provide greater pollination service than monoculture. Agriculture, Ecosystems & Environment, 301, 107031. https://doi.org/10.1016/j.agee.2020.107031.
本数据集采集自2011至2013年间，针对英国境内6处农林业（Agroforestry）样地开展的标准化样带行走调查。所有样地农户均已批准在其地块开展数据采集工作，研究方法细节已在上述发表论文中详述。
A至AA列用于记录样地信息、调查批次日期、样带位置及环境变量；AB至AP列则记录蜜蜂与食蚜蝇的丰度计数。其中，熊蜂（Bumblebee）按物种级别记录（AB至AN列），但熊蜂属的Bombus terrestris与Bombus lucorum合并为一个复合物种进行统计。独居蜂与食蚜蝇未鉴定至物种水平。
丰度计数列中出现的NA值，代表对应物种或类群的数据未纳入本次分析，剔除原因已在论文中说明。未经过剔除的完整数据集可通过申请获取。
以下为部分含义不直观的列名说明：
visit：对每个样地的调查批次按顺序编号。其中WAF样地无第8次调查数据，因该批次数据未纳入分析，具体原因详见论文。
jdate：距当年3月1日起的天数。
starttime / endtime：样带调查的开始与结束时间。若调查过程中需停下捕捉并鉴定蜜蜂，样带行走将暂停。因此各调查样带的总时长并不一致，但实际用于行走与访花昆虫搜寻的时长均已标准化。
landuse：用地类型，p代表牧草地（Pasture），a代表耕地（Arable）。
treatment：处理类型，AF代表农林业（Agroforestry），MC代表单作种植（Monoculture）。
alleywidth：树行间距，单位为米。
alleylength：树行长度，单位为米。
hedg.dist：样带至最近树篱的最短距离。
boundSR.all：田块边界（含树篱与边际带）的植物物种丰富度。
boundSR.ip：田块边界（含树篱与边际带）中虫媒授粉植物的物种丰富度。
bound.area：田块边界覆盖的总面积。
n.hedg.bound：树篱型田块边界的数量。
n.hedg.trees：田块边界内的树木数量。
snh：田块周边1km缓冲区内半自然生境（Semi-natural Habitat, SNH）所占百分比。
tran.pos：样带区段所处位置，分为树带边缘与树带中心两类。
tran.dist：每条样带被划分为25米的区段，该变量用于指定所属区段编号。
un：样带区段内受日照的时长占比（基于调查过程中的实际时间估算）。
beeact：蜜蜂活动活跃度的主观评定结果，分为低、中、高三个等级。
wind：调查期间的风力等级，采用蒲福风级（Beaufort Scale）标准。