The Effect of <i>Miscanthus</i> Cultivation on the Biodiversity of Ground Beetles (Coleoptera: Carabidae), Spiders and Harvestmen (Arachnida: Araneae and Opiliones)

In-crop invertebrate biodiversity of the perennial rhizomatous biomass crop Miscanthus was compared to the in-crop invertebrate biodiversity of adjacent agricultural land-uses.Ground beetles and arachnids (spiders and harvestmen) were used as indicators of invertebrate biodiversity and caught using pitfall traps over two years.Biodiversity measurements used were species richness, biomass, abundance, Simpson's Index, and rarity values.The Miscanthus plantation had a significantly lower ground beetle and arachnid species richness, biomass and abundance than an adjacent mixed-use arable field and a significantly lower ground beetle biomass and abundance than an adjacent grassland.Reduced weed vegetation and lack of insects that feed on Miscanthus are likely to be significant factors.The findings contradict the conclusions of a previous study of Miscanthus impact on butterflies.This is the first major study to assess the in-crop biodiversity of an established plantation and shows that Miscanthus invertebrate biodiversity is poor in established plantations, when compared to adjacent conventional agricultural land-uses.