Assessing non-ground dwelling arthropod diversity dynamics in Solenopsis invicta-invaded and non-invaded orchard-based agro-ecosystems by Malaise trap

The red imported fire ant (RIFA, <i>Solenopsis invicta</i>) presents a substantial threat to ecosystems, yet its impact on flying arthropods-based diversity within orchard environments remains insufficiently studied, especially using the Malaise trap approach. Although existing research frequently reports declines in native arthropod populations due to RIFA invasions, detailed assessments across various orchard habitats and studies employing Malaise traps are notably limited.This study examines the effects of RIFA invasion on arthropod community dynamics and diversity across guava and cherimoya orchards. Significant upward trends in RIFA worker ant abundance were observed in guava and cherimoya orchards, with peak activity in May 2023, while nest density remained stable across all orchards. Higher occurrence levels in cherimoya orchards suggest elevated invasion intensity and heightened susceptibility to RIFA impact. Analyses of arthropod diversity reveal that although invaded areas showed higher species abundance and family richness, diversity indices were generally higher in non-invaded areas, implying a potential minor negative influence of invasion on orchard-based ecosystem biodiversity. Correlation analysis indicated that temperature, precipitation, and humidity positively influence arthropod abundance and family richness, particularly in invaded areas, while atmospheric pressure has a suppressive effect. PCA and RDA analyses revealed distinct clustering patterns and ecological responses, with temperature as a key environmental factor shaping insect community structure. Hedges' g effect size analysis showed non-significant trends toward increased species abundance and minor changes in family richness in invaded areas, indicating minimal impact of RIFA invasion on these biodiversity measures. These findings underscore the nuanced effects of RIFA invasion on arthropod communities and highlight the importance of environmental factors in shaping community responses in orchard-based agro-ecosystems.