Bees increase seed set of wild plants while the proportion of arable land has a variable effect on pollination in European agricultural landscapes
Background and aims – Agricultural intensification and loss of farmland heterogeneity have contributed to population declines of wild bees and other pollinators, which may have caused subsequent declines in insect-pollinated wild plants. Material and methods – Using data from 37 studies on 22 pollinator-dependent wild plant species across Europe, we investigated whether flower visitation and seed set of insect-pollinated plants decline with an increasing proportion of arable land within 1 km. Key results – Seed set increased with increasing flower visitation by bees, most of which were wild bees, but not with increasing flower visitation by other insects. Increasing proportion of arable land had a strongly variable effect on seed set and flower visitation by bees across studies. Conclusion – Factors such as landscape configuration, local habitat quality, and temporally changing resource availability (e.g. due to mass-flowering crops or honey bee hives) could have modified the effect of arable land on pollination. While our results highlight that the persistence of wild bees is crucial to maintain plant diversity, we also show that pollen limitation due to declining bee populations in homogenized agricultural landscapes is not a universal driver causing parallel losses of bees and insect-pollinated plants. ; EU FP5 QLRT-2001-01495 ; Swiss Federal Office for Science and Technology (01·0524-2) ; FORMAS ; Estonian Ministry of Education and Research IUT (IUT20-33) ; Internal Grant Agency of the Faculty of Environmental Sciences Czech University of Life Sciences Prague 42900/1312/3166 ; MC-CIG BeeFun project: PCIG14-GA-2013-631653 ; DAFM ; IRC ; Formas (2018-01466) ; German Ministry of Research and Education (FKZ: 01LC1104A) ; NKFIH project (FK123813) ; NKFIH (KKP 133839) ; European Union in the 7th Framework Programme (grant 244090), ; MTA Bolyai Fellow ; Peer reviewed