查看文章

Biological invasion has been considered as an important component of global environmental changes (Vitousek et al. 1997) and a leading cause of decline and/or loss of native biodiversity (Ricciardi et al. 1998, Kohli et al. 2004) and ecosystem services (Pejchar and Mooney 2009). With steady increase in human movement and global trade, the intensity of biological invasion has been increasing in all ecosystems and landscapes. The negative impact of invasive species is further exacerbated by ongoing climate change because the later has been projected to increase both frequency and intensity of biological invasion (Simberloff 2000). The problem of invasive species is prevalent both in developed as well as developing countries, but their impact is likely to be higher in developing countries like Nepal due to lack of expertise and limited resources available for their management. Nepal lies at the cross-road of six floristic provinces of Asia (Sino-Japanese, Southeastern Asiatic, Indian, Sudano-Zambian, Irano-Turranean and Central Asiatic) and the floral elements of all provinces are represented in Nepal (Dobremez 1976, as cited in TISC 2002). With the widest elevation gradient and heterogeneous geomorphology, organisms from anywhere of the world may find suitable habitat and climatic condition in Nepal. There are at least 219 alien species of flowering plants (Tiwari et al. 2005, Siwakoti 2012, Sukhorukov 2014) and 64 species of animals (Budha 2015) that are naturalized in Nepal. An assessment of invasive alien plant species (IAPS) was undertaken for the first time by IUCN Nepal during 2002-2003 and reported 21 naturalized (ie alien …