Impact of an invasive tree on arthropod assemblages in woodlots isolated within an intensive agricultural landscape

Abstract

AbstractAimLandscape simplification and the spread of invasive species are considered beyond the main threats to global biodiversity. It is well recognized that non‐crop habitats bring complexity to farmland and provide refuge for a wide range of organisms, including arthropods. However, knowledge about the effects of invasive trees on arthropods in non‐crop habitats in intensive agricultural landscapes is still weak. Therefore, we examined differences in the arthropod assemblages between woodlots formed by the invasive black locust (Robinia pseudoacaciaL.) and by native deciduous tree species in the intensive agricultural landscape.LocationCzech Republic, Central Europe.MethodsWe used a multi‐taxonomic approach to record arthropod assemblages using various sampling methods. The impacts of woodlot habitat structure were investigated across 13 arthropod taxa from different trophic levels.ResultsTotal abundance and species richness of all arthropods and the majority of the herbivore taxa were lower inR. pseudoacaciawoodlots, likely due to losses of the forest canopy specialists. The forest specialists were associated with the native woodlots with more developed canopy and shrub layers. The impoverished diversity of the forest specialists and canopy herbivores in theR. pseudoacaciawoodlots was partly compensated by the higher presence of species exploiting a well developed herb layer and open‐habitat specialists, including threatened species.Main conclusionsNative woodlots and those formed byR. pseudoacaciadiffer in vegetation structure and host different assemblages of arthropods. Therefore, parallel presence of both types of woodlots supports arthropod diversity in otherwise simplified agricultural landscapes through creating more complex mosaic of habitats.