Habitat age affects beetle diversity in wildflower areas

Abundance, species richness, diversity and evenness of beetles inhabiting the vegetation layer in twenty 1–4 year old wildflower areas and winter wheat fields were compared to investigate the role of habitat age for biodiversity. Total beetle abundance and also abundance of economically important pest beetles decreased significantly with age of wildflower areas, showing that wildflower areas did not promote large populations with habitat age. Beetle species richness was significantly higher in 2–4 year old wildflower areas than in wheat. Diversity and evenness increased significantly with habitat age. Beetle species composition of wheat differed clearly from that in wildflower areas. Beetle assemblage was significantly associated with plant species richness, vegetation structure and plant biomass, accounting for 11.75, 10.73 and 9.71% of the total variance, respectively. It is therefore recommended to maintain a mosaic of wildflower areas of different age to conserve high beetle diversity in agroecosystems.

► Beetle species richness, diversity and evenness increase with advancing age of wildflower areas. ► Economically important beetles are not enhanced by wildflower areas. ► Establishing wildflower areas is recommended to further beetle diversity.