Invasive Chromolaena odorata Infestation Supports Increased Arthropod Diversity in Southern Nigeria

Background and Objective: The highly invasive Chromolaena odorata(Siam weed) is well recognized as a plant that alters ecosystem composition and trophic functionality. Although these changes are mostly deleterious to native plant species, little is known about their impact on associated arthropod communities. This study investigated how C. odorata invasion influences arthropod community assemblage. This study compared the diversity, richness and evenness of arthropods in sites without C. odorata (0% C. odorata-infested site) and with C. odorata (>50% C. odorata-infested sites). Materials and Methods: Pitfall traps and beating tray sampling techniques were used to sample both epigeal and arboreal arthropods, respectively and collected arthropods were identified at the family level. Diversity at the family level was analyzed using richness, Shannon and Simpson indices, calculated in PAST software (version 4.03). Results: The results suggest that sites with >50% C. odorata coverage supported higher arthropod family richness, diversity and evenness compared to the 0% C. odorata uninfested site, contradicting the initial expectations. Although a 51% Jaccard similarity index suggests a moderate overlap in family composition within the two study sites, this study contrasts the typical expectation of reduced arthropod diversity following the invasion of an aggressive plant species. Conclusion: The study uniquely demonstrates that C. odorata invasion may enhance certain aspects of arthropod community structure, providing new insights into the complexity of ecosystem responses to invasive species.