Community-level impacts of plant invasion in tropical forests of Northeast India

Abstract

Invasive plants disrupt ecosystems by influencing species interactions, aiding co-invader integration, and worsening competition for native plants. Successful forest invasive species management relies on grasping these interaction patterns at the community level. This study aims to assess the community attributes of invasive plants in tropical forests of Northeast India, examining their dominance in various habitats, elucidating their influence at the community level and some species-specific effects on associated co-invaders and non-invasive groups. The present investigation recorded 101 invasive plant species mostly of neotropical origin, comprising of grasses, sedges, forbs, shrubs, trees, and vines. The findings revealed both positive and negative effects of invasive species richness and their percentage at community level and throughout different habitats. However, the presence of dominant invasive species caused a substantial decrease in species diversity of plant community in the study area, depicting a significant negative association with the non-invasive group and a notable positive association with the co-invasive group. These findings offer valuable insights by specifying the community-level impacts of exotic invaders on the natural plant population which will be very helpful in devising effective management plans to counter biotic invasion in the biodiversity rich tropical forested landscapes.