Invasive Species Echinochloa colona Reduces Abundance and Diversity of Resident Plant Communities in Tropical Wetland

Abstract

Although the relationship between invasive alien species (IAS) and pla nt community structure has attracted considerable interest, the impact s of IAS on abundance and diversity of resident plant communities in s pecies rich-ecosystems, such as tropical wetlands are poorly understoo d. Consequently, this has impeded development of improved management s trategies and successful restoration of invaded tropical wetlands. The refore, data on vegetation were collected from 60 plots of 20 × 50 m t o study the impacts of alien invasive grass Echinochloa colona (L.) Li nk abundance on plant community abundance, richness, evenness and dive rsity of resident plant species within grasslands of the Kilombero Val ley wetland, Tanzania. Moreover, the impacts of abundance of E. colona on plant functional groups (i.e. graminoids, forbs and shrubs) richne ss were also explored. Generalized linear models showed that community richness, evenness, diversity and abundance of resident species were negatively related to the E. colona abundance. There was a negative re lationship between richness of graminoids and shrubs and the abundance of E. colona. Similarly, the abundance of graminoids, forbs and shrub s is related negatively to the abundance of E. colona. Given that most of the community and functional group attributes of resident plants i s related negatively to E. colona abundance, improved management strat egies should be developed to minimize the abundance and further spread of E. colona to restore and conserve wetland biodiversity.