Mixed plant and arthropod biodiversity responses to solar park establishment on former agricultural lands

Abstract Ground‐mounted solar parks in Europe are often implemented in agricultural landscapes on fields with agricultural history. The subsequent decrease in management intensity presents opportunities for biodiversity development, which might especially be interesting for arthropods and their resources, given their ongoing biodiversity losses in agricultural landscapes. While several studies suggest that solar parks have the potential to enhance pollinator biodiversity, impacts on other arthropods remain unclear and there is limited knowledge on how these shifts compare to pre‐conversion biodiversity and the potential of solar parks to contribute to biodiversity conservation. In this study, we used field surveys and insect trapping to compare flower resources, vascular plant diversity, pollinator diversity and soil‐emergent arthropod diversity in Dutch solar parks to previous land use (i.e. intensive agricultural grasslands) and semi‐natural conditions (i.e. extensively managed grasslands). Flower and nectar plant availability, wild bee and hoverfly abundance, but not butterfly abundance, were significantly higher in solar parks than in intensive grasslands. Vascular plant diversity was similar in solar parks and extensive grasslands, and higher than in intensive grasslands. Overall soil‐emergent arthropod richness was similar across all habitat types, yet biomass and abundance were lower in solar parks than in the other habitats. Community composition differed between habitat types across all studied arthropod groups. Synthesis and applications . Our results suggest that while biodiversity can increase in solar parks post‐conversion compared to previous land use, not all taxonomic groups benefit from the land use change. Potential benefits for certain groups (particularly for butterflies and soil‐emergent arthropods) are likely lost due to disturbance during land conversion and solar panel presence. As a result, our study indicates that solar parks have the potential to combine biodiversity conservation on the surfaces not covered by solar panels, but that more insight is needed in the solar park design (e.g. conversion process and row width) and management, particularly to improve butterfly and soil‐emergent arthropod biodiversity.