Vertebrate grazing can mitigate impacts of nutrient addition on plant diversity and insect abundance in a semi-natural grassland

Human-induced nutrient eutrophication is a major threat to grassland biodiversity, because it promotes the dominance of fast-growing plants. Negative impacts of fertilization on plant biodiversity may be offset by grazing by large vertebrate herbivores. However, whether grazers also mitigate impacts of nutrient addition on insects is less well understood. We use a field experiment to test how plant communities and abundances of pollinators and grasshoppers respond to nutrient addition and grazing by different assemblages of large herbivores, i.e., access by all herbivores (including cattle and horses), access by wild herbivores only (wild boar and deer), no access by large herbivores. Plant biomass increased, plant diversity decreased and community composition shifted towards lower forb cover in response to fertilization, but only in the absence of all herbivores. Flower visitation by Hymenoptera (bees and wasps), i.e., the most abundant pollinator group, was reduced by nutrient additio..., Study system: We set up a field experiment with nutrient addition and grazing treatments in a semi-natural grassland in the Veluwe area in the Netherlands (52.03 °N, 5.80 °E) (e.g., Kardol et al. 2006, Hannula et al. 2017, Veen et al. 2018). The field site is located on a loamy, sandy mineral soil (Kardol et al. 2006). The mean annual temperature was around 10.7°C and the mean annual precipitation was approximately 840 mm (Veen et al., 2018; Royal Netherlands Meteorological Institute (KNMI)). The field has been used for agriculture and was abandoned in 1982. Since then, it has been managed by Natuurmonumenten as nature reserve and has developed into a grassland with a Plantagini-Festucion plant community (Kardol et al. 2006). The grassland is visited by naturally occurring herbivores, including roe deer (Capreolus capreolus), mainly a browser, and red deer (C. elaphus), a mixed feeder, and wild boar (S. scrofa), a facultative herbivore. European hares and rabbits occur in the area, but ..., , # Vertebrate grazing can mitigate impacts of nutrient addition on plant diversity and insect abundance in a semi-natural grassland

[https://doi.org/10.5061/dryad.47d7wm3nf](https://doi.org/10.5061/dryad.47d7wm3nf)

## Description of the data and file structure

This dataset contains one file with five worksheets.

| **Worksheet: Plot and plant variables** |   |   |   | |
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