Status and impact assessment of invasive alien plant species (IAPS): a case study from Galyang Municipality, Syangja Nepal.
Invasive alien species are non-native species of plants or animals which spread and dominate new areas and are believed to cause harm to the environment, ecosystems and human well-being. Present study was conducted in Ward 11 of Galyang Municipality in Syangja district of Nepal to document the status of invasive alien plant species (IAPS) and find out the impact of such IAPS to local livelihoods through ecological assessment, household survey and regeneration survey in different land use types. A total of sixteen different IAPS were recorded, but were dominated by Ageratum houstonianum, Bidens pilosa, Chromolaena odarata. The present study showed that the diversity of IAPS was inversely proportional to altitude and dense forest stand. The regeneration density of desired species was found to be 5107/ha in invaded areas and 11556/ha in non-invaded areas. Fallow land and rangeland were observed to be most invaded land use types with greatest economic loss in rangeland. In case of forest, the impact on regeneration was high in open canopy and areas having high levels of grazing impact. Local people are responding to increasing invasion through hand removal and use of IAPS biomass as mulch and fuel wood for controlling the invasion in the study area.