Agricultural intensification, with its associated habitat loss and fragmentation, is among the most important drivers of the ongoing pollination crisis. In this quasi-experimental study, conducted in intensively managed vineyards in southwestern Switzerland, we tested the separate and interdependent effects of habitat amount and fragmentation on the foraging activity and reproductive performance of bumblebee Bombus t. terrestris colonies. Based on a factorial design, we selected a series of spatially replicated study sites across a dual gradient of habitat amount (area of ground-vegetated vineyards) and fragmentation (density of ground-vegetated vineyard fields) in a landscape predominantly consisting of vineyards with bare grounds. The foraging activity of individual bumblebees was measured using the radio frequency identification (RFID) technology, and we assessed final colony size to measure reproductive performance. We found an interactive effect of habitat amount and fragmentation on colony size. More specifically, the degree of fragmentation had a negative effect on bumblebee colony size when the amount of habitat was low, while it had a weak positive effect on colony size in landscapes with high amounts of habitat. At the level of individual vineyard fields, ground vegetation cover exerted a positive effect on bumblebee colony size. Fragmentation, but not habitat amount, significantly influenced foraging activity, with more foraging trips in sites with lower degrees of fragmentation. Our results emphasise the importance of studying the separate and interdependent effects of habitat amount and fragmentation to understand their influence on pollinators, providing guidance for optimising the spatial configuration of agricultural landscapes from a biodiversity viewpoint.

中文翻译：

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栖息地数量介导了破碎对传粉者繁殖性能的影响，但对它的觅食行为没有影响。

农业集约化及其相关的栖息地丧失和破碎化，是持续进行的授粉危机的最重要驱动因素之一。在瑞士西南部的集约化管理葡萄园中进行的这项准实验研究中，我们测试了栖息地数量和碎片化对大黄蜂Bombus t觅食活动和生殖性能的相互独立影响。陆地植物殖民地。基于因子设计，我们在主要由裸露的葡萄园组成的景观中，选择了一系列在生境数量（地上葡萄园的面积）和破碎（地上葡萄园的密度）的双重梯度上进行的一系列空间复制研究地点理由。使用射频识别（RFID）技术测量了单个大黄蜂的觅食活动，并且我们评估了最终的菌落大小来衡量繁殖性能。我们发现栖息地数量和碎片化对菌落大小的相互作用。更具体地说，在生境数量少的情况下，破碎程度对大黄蜂菌落的大小有负面影响，而在有大量生境的景观中，碎裂的程度对土蜂的大小没有积极影响。在单个葡萄园田地上，地面植被覆盖对大黄蜂菌落的大小产生了积极影响。破碎而不是栖息地的数量会严重影响觅食活动，在破碎程度较低的地点会有更多的觅食行程。