Plant Invasion Research in Nepal: A Review of Recent National Trends

Mohan Pandey, Khum Bahadur Thapa-Magar , Buddhi Sagar Poudel , Thomas Seth Davis and Bharat Babu Shrestha

Keywords:

Invasive Alien Plant Species, IAPS, Web of Science, research trends, research gaps

Abstract:

Research interests in Invasive Alien Plant Species (IAPS) have expanded globally, and nationally in Nepal, over the last few decades. Here we provide a systematic compilation and analysis of the scientific literature to explore research trends and identify research gaps in plant invasion biology in Nepal. We compiled and examined journal publications retrieved from Web of Science (WOS) and other databases (NepJOL, Google Scholar, and other bibliographies) using specific search keywords. The search yielded 86 research studies on IAPS, published between 1958 and 2020 (up to August 2020) that met our pre-determined criteria. The number of publications in national journals that focused on IAPS increased, starting in 2000, but this increase was not notable in international journals, until 2010. Nearly 91 % of the studies that appeared in international journals were published after 2010. A majority of the studies focus on biology, ecology, and ecological impact studies of a few selected IAPS, especially mile-a-minute (Mikania micrantha Kunth), parthenium weed (Parthenium hysterophorus L.), and crofton weed (Ageratina adenophora (Spreng.) R.M. King & H.Rob.), mostly in Nepal’s forest ecosystems. Eightyfour percent (84%) of field-based studies have been conducted in the central region of Nepal (Bagmati and Gandaki provinces together). Tribhuvan University, a Government-funded, National University of Nepal, was the largest contributor to IAPS related research and our analysis revealed that international grants were the primary funding sources for this research. We conclude that future regional research should be prioritized on thematic areas focusing on: (a) understudied phytogeographic regions, (b) impacts on protected areas, (c) under-studied invasive and naturalized species, (d) IAP dispersal mechanisms, and (e) economic impacts. Additional research in these priority areas will help to focus our understanding of IAPS in Nepal and will be important for mitigating ecological and economic damages from IAPS. Also, funding from government agencies for research, and incentives for graduate students to publish their theses, may improve the knowledgesharing aspects related to the above themes and reduce biases in areas that we identified in this review.