Floral visitor species present in flowers of the ground herb in the Andalusia olive groves

We sampled the abundance and diversity of flower-visiting insects in paired olive farms located in Andalusia. The surveys were carried out in 18 paired olive farms in 2018, and in 24 paired olive farms in 2020. On the one hand, each pair of olive farms is constituted by an olive farm with low-intensive herb cover management and an olive farm with intensive herb cover management. The low-intensive management consists of the maintenance of herb cover during most of the year being only removed in late spring by mechanic mowing or livestock grazing. Conversely, intensive management consists of removing the herb cover permanently by using pre-emergence and/ or post-emergence herbicides, sometimes in combination with ploughing the ground several times a year. On the other hand, the pair of farms in each locality is surrounded by the same landscape complexity. We classified each pair of farms into three categories of landscape complexity (simple, intermediate, and complex) according to the proportion of semi-natural area estimated within a 2 km radius buffer around the centroid of each pair of farms. Surveys were conducted in multi-specific floral stands. We selected two 10 m2 multi-floral stands per olive farm located inside the olive field matrix. They were carried out twice for 2018, and monthly from March to June for 2020 (3 sampling rounds in total), matching the peak flowering period of the ground herb cover. Sampling consisted of recording the abundance and diversity of flower-visiting insects in each floral patch for 15 minutes in the morning (until 13 h) and for 15 minutes in the afternoon (until 17 h) every sampling round. The diversity and abundance of insect floral visitor by transect was pooled by population/locality ('SUMMARY_Floral_visitors_pop.csv' file).

本研究针对安达卢西亚（Andalusia）地区的配对式橄榄园，开展访花昆虫的丰度与多样性采样调查。该调查于2018年覆盖18对橄榄园，2020年扩展至24对橄榄园。一方面，每对橄榄园由采用低强度草本覆盖管理模式的橄榄园与采用高强度草本覆盖管理模式的橄榄园共同组成；低强度管理模式指全年多数时间保留草本覆盖，仅在晚春通过机械刈割或放牧方式移除草本植被。与之相反，高强度管理模式则通过使用苗前除草剂和/或苗后除草剂永久清除草本覆盖，部分年份还会结合每年数次的土壤翻耕操作。另一方面，同一区域内的每对橄榄园所处的景观复杂度一致。本研究依据每对橄榄园中心点周边2公里缓冲区内的半自然生境占比，将所有橄榄园对划分为简单、中等、复杂三类景观复杂度等级。调查在多物种花卉斑块中开展，每个橄榄园内我们在橄榄种植区域内选取2个面积为10平方米的多花卉斑块作为采样点。2018年的调查共开展2次，2020年则于3月至6月每月开展1次（总计3轮采样），所有采样均与地表草本植被的盛花期相匹配。每轮采样中，我们于上午（至13时）和下午（至17时）分别在每个花卉斑块内耗时15分钟，记录访花昆虫的丰度与多样性。各样带的访花昆虫丰度与多样性数据将按种群/区域进行汇总，对应数据存储于"SUMMARY_Floral_visitors_pop.csv"文件中。