Beneficial insects play a key role in maintaining ecosystem functioning and biodiversity in agricultural landscapes by providing essential ecosystem services such as pollination and biological pest control. This study investigates spatial and seasonal patterns in the abundance and community composition of selected groups of beneficial arthropods across agricultural landscapes in Germany.
Insect sampling was conducted in four regions representing different landscape structures and management intensities (Hesse, Brandenburg, Baden-Württemberg, and Saxony). Standardized sampling grids were established in each region, and insects were collected using malaise traps and pitfall traps, which were deployed for two-week sampling periods across multiple seasons. Samples were preserved in ethanol and processed in the laboratory, with a focus on key beneficial arthropod groups, including bees (Hymenoptera: Apidae), parasitoid wasps (Hymenoptera: Parasitica), hoverflies (Diptera: Syrphidae), and ground beetles (Coleoptera: Carabidae).
Due to the labor-intensive nature of insect identification and counting, statistical analyses in this report were restricted to samples collected in Brandenburg and Baden-Württemberg during the 2024 sampling season.
Non-parametric statistical analyses were used to assess differences in arthropod abundance and community composition across spatial and temporal scales.
The results indicate that seasonality was a dominant factor influencing both arthropod abundance and community composition. While total arthropod abundance showed limited variation among sampling grids, clear regional differences and taxon-specific spatial patterns were observed, particularly for Carabidae. Multivariate analyses further revealed pronounced seasonal shifts in arthropod community composition. Although based on first-year data, these findings provide a valuable baseline for understanding temporal and spatial variability of beneficial arthropods in agricultural landscapes.