Flying insect biomass is negatively associated with urban cover in surrounding landscapes

Aim
In this study, we assessed the importance of local to landscape-scale effects of land cover and land use on flying insect biomass. Our main prediction was that insect biomass would be lower within more intensely used land, especially in urban areas and farmland. Location Denmark and parts of Germany.
Methods
We used rooftop-mounted car nets in a citizen science project (‘InsectMobile’) to allow for large-scale geographic sampling of flying insects. Citizen scientists sampled insects along 278 five km routes in urban, farmland and semi-natural (grassland, wetland and forest) landscapes in the summer of 2018. The bulk insect samples were dried overnight to obtain the sample dry weight/biomass. We extracted proportional land use variables in buffers between 50 and 1000 m along the routes and compiled them into land cover categories to examine the effect of each land cover, and specific land use types, on insect biomass.
Results
We found a negative association between urban cover and in...

研究目标
本研究旨在评估局地至景观尺度下土地覆盖（land cover）与土地利用（land use）对飞行昆虫生物量（flying insect biomass）的影响效应及其重要性。我们的核心预测为：人类开发强度越高的土地内，飞行昆虫生物量越低，尤以城市区域与农田最为显著。
研究区域
丹麦及德国部分区域。
研究方法
本研究依托名为"InsectMobile"的公民科学项目，采用车顶安装的昆虫采样网开展飞行昆虫的大尺度地理采样。2018年夏季，公民科学家在城市、农田以及半自然（草地、湿地与森林）景观中，沿278条5公里长的采样路线采集昆虫。将采集得到的混合昆虫样品进行过夜干燥处理，以获取样品干重（即生物量）。我们沿各采样路线在50米至1000米的缓冲区内提取土地利用比例变量，并将其归类为土地覆盖类别，以此分析各类土地覆盖类型与具体土地利用方式对昆虫生物量的影响效应。
研究结果
我们发现城市覆盖度与……呈负相关关联