Effects of Crop Rotation Diversification and Livestock Integration on Above-Ground Arthropod Dynamics Under Conservation Agriculture.

Diversification through integrating diverse crop species and livestock is key to enhancing above-ground arthropod diversity and promoting the sustainability of cropping systems within conservation agriculture (CA) in South Africa. This study compared two crop rotation treatments, A (Wheat-Wheat-Wheat-Wheat) and G (Canola-Medics-Wheat-Medics), as part of a long-term CA trial conducted in a wheat-producing region of South Africa. For crop rotation system G, each phase of the rotation sequence was represented in separate plots annually. Surface-dwelling arthropods were sampled using pitfall traps, while plant-dwelling arthropods were captured through sweep-net sampling. These methods comprehensively assessed above-ground arthropod diversity 90 days after crop emergence. The results showed that crop rotation diversification positively influenced arthropod diversity, though the effects varied depending on the arthropod group and sampling position. Ground-dwelling arthropods exhibited less pronounced differences between crop rotation systems, whereas plant-dwelling arthropods displayed more crop-specific variations. Analysis of individual arthropod orders revealed that the effects of crop rotation diversification varied across different arthropod groups. Our findings emphasize the importance of examining multiple arthropod groups to understand diversification's impacts fully within CA farming systems.