IMPACT OF Lantana camara L. INVASION ON VEGETATION DIVERSITY AND SOIL MICROBIAL POPULATION IN DHADING, CENTRAL NEPAL

Abstract

Lantana camara L. a plant from Verbenaceae family is one of the 100 worst invasive plant. This present study was conducted to assess the impact of Lantana camara L. on vegetation and soil microbes in Dhunibesi municipality, Dhading, Nepal. Random stratified sampling method was used with two categories: Invaded and Non-invaded. Total of 100 quadrates, 50 quadrates in each category of 10×10m were laid and inside of each plot three sub-plots of 5×5m for shrubs and 1×1m for herbs were laid in each category. Vegetation and soil attributes were studied in each category. A total of 159 species (103 in invaded and 139 in non-invaded sites) belonging to 73 families were recorded from the study sites. The density and frequency of other plant species were decreased in the area invaded by L. camara as compared to the non-invaded sites. Plant density, Simpson's diversity (D), Concentration of dominance, Shannon-wiener index (H), Species richness and evenness varied significantly (t-test, p<0.05) among the categories. These variables were lowest in invaded sites and highest in non-invaded sites. Analysis of similarity index showed the significant change, (p<0.05) in vegetation composition among the invasion and non invasion condition for all growth forms. pH of soil was found higher in invaded sites than the non-invaded sites but the change in pH was not significant. Invasion of L. camara also influenced the soil microbe population. Population of bacteria and fungi were found significantly higher in non-invaded sites and lower in invaded sites. A total of 34 species (29 from non-invaded and 22 from invaded sites) of fungi were recorded from the soil of study sites. The species richness of fungi was found significantly higher in non-invaded sites. The study concludes that the invasion of L. camara changes the vegetation density, frequency, species diversity, evenness and species composition along with soil pH, soil microbe population and fungal species composition. The significant differences in these parameters suggest that L. camara is changing the vegetation and soil microbe composition and diversity in Dhunibesi so required to manage and remove the L. camara for the protection of species diversity.