Impact of tobacco-soybean intercropping on ground-dwelling arthropod communities under different planting schemes

Intercropping has the potential to enhance crop yields by modifying the farmland ecosystem. However, its influence on ground-dwelling arthropod communities, especially in disturbance-sensitive environments, such as karst areas, remains inadequately understood. To address this knowledge gap, we conducted a study from April to September 2023, in a karst area to evaluate the impacts of tobacco-soybean intercropping on ground-dwelling arthropods and soil properties. Trapping methods were used to examine arthropod communities under 5 crop planting schemes: tobacco monoculture (CK1), soybean monoculture (CK2), soybean ridge and furrow intercropping (T1), soybean single-sided ridge intercropping (T2), and strip intercropping with alternate soybean and tobacco furrows (T3). Formicidae were the predominant taxa across all planting schemes, with more shared taxa than unique taxa among the planting schemes. Arthropod community composition was stable among the planting schemes, but notable variation was observed among tobacco growth stages. Although intercropping schemes did not significantly impact arthropod density and diversity, these metrics were lower during the seedling stage compared with other growth stages. The densities of herbivores and detritivores under CK2 were significantly higher than those observed under the other planting schemes. Predator and omnivore densities were not affected by the intercropping scheme. Total phosphorus content and soil compaction were critical soil properties that influenced arthropod communities, suggesting that these variables play a crucial role in shaping the trophic structure of the community under intercropping regimes. These findings highlight the potential for optimization of intercropping strategies to enhance ground-dwelling arthropod biodiversity and promote sustainable agricultural practices in karst regions.