Multiple invasions exert combined magnified effects on native plants, soil nutrients and alters the plant-herbivore interaction in dry tropical forest

Background

Globalization has resulted in a higher number of species invasions, which have had detrimental impacts on ecosystem biodiversity, functions, and services. Assessment and management of all invasive species is based on knowledge of a small number of species. Management is also focused on single-species invasions rather than multiple simultaneous invasions. India has a high level of species invasions and minimal resources to control them.

Research Goals and Methods

This study aims to highlight the importance of the interactive effects of multiple simultaneous species invasions. Lantana camara and Pogostemon benghalensis are the focal species of this study. This study was conducted in the core region of the Kanha Tiger Reserve where both the independent and combined effects of both species invasions were measured. The authors predicted that the combined effects of two invasive species at once would have greater detrimental impacts on native plants, soil nutrients, and herbivory than would the effects of a single invasive species.

Conclusions and Takeaways

The authors determined that plant invasions in a seasonally dry tropical forest of India correlates with decline in native plant abundance and species richness, increase in soil potassium, decrease in native plants, and increased herbivory pressure on native plants. Overall, these impacts were magnified in areas where co-invasion by the two species occurred. L. camara had heavier impacts alone than did P. benghalensis. The authors state that based on their results, regular thinnings of L. camara and P. benghalensis should be done to promote the growth of native species. Removal should be done in the summer months when the plants shed their leaves, allowing more sunlight to penetrate the forest crown and reach native species. Authors state that determining areas of prioritization and customizing management techniques to species and region will result in more effective invasive species control.