Data from: Wildflower strip establishment supports beneficial ground-dwelling arthropods and pest control but has limited effects on weed seed control and spillover to adjacent fields

Recent arthropod declines in agricultural landscapes can threaten
biodiversity and the provision of ecosystem services. Wildflower strips
(WFS) represent popular measures to support biodiversity. Most studies
investigated their effects on pollinators, whereas ground-dwelling
arthropods are less studied. In addition, time after WFS establishment is
a relevant factor, but most experiments are performed in a single season.
Here, we evaluated the effects of WFS on ground-dwelling arthropods
(carabids, spiders, and myriapods) and ecosystem services (pest and weed
seed predation) across three years. Using a standardised experimental
design with paired control and WFS margins in 12 fields, we sampled before
and up to the first two years after WFS establishment while also assessing
spillover into adjacent fields. Our analyses revealed that spiders, as
well as total pest predation and predation by rodents, were enhanced in
two-year-old WFS, whereas similar but weaker patterns were observed for
carabid and myriapod species richness. Spillover patterns were weak, and
only carabid species richness was enhanced in parts of the field
neighbouring WFS. These results reinforce the important role of perennial
WFS in supporting beneficial ground-dwelling arthropod groups while also
highlighting that taxon-specific responses can hinder the design of
general measures to support biodiversity on arable land.