Most studies focusing on the effects of urban land use on pollinators have compared urban sites with
one type of rural site. However, there is a lot of variation in the amount of natural habitats or intensive
agriculture in rural areas. The position of urban areas within that continuum in terms of pollinator communities
remains unclear. In this work, we studied bee and hoverfly communities (abundance, diversity,
and species composition) in three site types along two river systems crossing urban areas, rural areas
dominated by agriculture (termed rural-agricultural) and rural areas with high amounts of semi-natural
land use (termed rural-natural). Pollinators were caught in August 2011. Abundance and diversity were
highest in rural-natural sites for both taxonomic groups. Our data also indicate that hoverflies and bees
responded differently to the surrounding land use, with bee abundance and diversity only significantly
reduced in rural-agricultural sites but not in urban sites, and hoverfly abundance and diversity only
significantly reduced in urban sites but not in rural-agricultural sites. The observed differences in the
response of pollinators point out the importance of incorporating different types of rural land use and
clearly defining the rural end of an urban–rural gradient in getting a clear view on how urban land use
affects a specific pollinator group. Year-round sampling of these pollinators would, however, probably
enable a more accurate view on these responses.
Most studies focusing on the effects of urban land use on pollinators have compared urban sites withone type of rural site. However, there is a lot of variation in the amount of natural habitats or intensiveagriculture in rural areas. The position of urban areas within that continuum in terms of pollinator communitiesremains unclear. In this work, we studied bee and hoverfly communities (abundance, diversity,and species composition) in three site types along two river systems crossing urban areas, rural areasdominated by agriculture (termed rural-agricultural) and rural areas with high amounts of semi-naturalland use (termed rural-natural). Pollinators were caught in August 2011. Abundance and diversity werehighest in rural-natural sites for both taxonomic groups. Our data also indicate that hoverflies and beesresponded differently to the surrounding land use, with bee abundance and diversity only significantlyreduced in rural-agricultural sites but not in urban sites, and hoverfly abundance and diversity onlysignificantly reduced in urban sites but not in rural-agricultural sites. The observed differences in theresponse of pollinators point out the importance of incorporating different types of rural land use andclearly defining the rural end of an urban–rural gradient in getting a clear view on how urban land useaffects a specific pollinator group. Year-round sampling of these pollinators would, however, probablyenable a more accurate view on these responses.
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