Ethnomedicinal landscape: distribution of used medicinal plant species in Nepal.

BACKGROUND: The risk of losing traditional knowledge of medicinal plants and their use and conservation is very high. Documenting knowledge on distribution and use of medicinal plants by different ethnic groups and at spatial scale on a single platform is important from a conservation planning and management perspective. The sustainable use, continuous practice, and safeguarding of traditional knowledge are essential. Communication of such knowledge among scientists and policy makers at local and global level is equally important, as the available information at present is limited and scattered in Nepal. METHODS: In this paper, we aimed to address these shortcomings by cataloguing medicinal plants used by indigenous ethnic groups in Nepal through a systematic review of over 275 pertinent publications published between 1975 and July 2021. The review was complemented by field visits made in 21 districts. We determined the ethnomedicinal plants hotspots across the country and depicted them in heatmaps. RESULTS: The heatmaps show spatial hotspots and sites of poor ethnomedicinal plant use documentation, which is useful for evaluating the interaction of geographical and ethnobotanical variables. Mid-hills and mountainous areas of Nepal hold the highest number of medicinal plant species in use, which could be possibly associated with the presence of higher human population and diverse ethnic groups in these areas. CONCLUSION: Given the increasing concern about losing medicinal plants due to changing ecological, social, and climatic conditions, the results of this paper may be important for better understanding of how medicinal plants in use are distributed across the country and often linked to specific ethnic groups.

Medicinal plants and ethnomedicine in peril: a case study from Nepal himalaya.

The impacts of climate change were severe on indigenous medicinal plant species and their dependent communities. The harvesting calendar and picking sites of these species were no longer coinciding and the changes were affecting harvesters' and cultivators' abilities to collect and use those species. Secondary sites: road-heads, wastelands, regenerated forests, and so forth, were being prioritized for collection and the nonindigenous medicinal plant species were being increasingly introduced into the medical repertoire as a substitution and to diversify the local medicinal stock. Acceptance and application of nonindigenous species and sites for livelihood and ethnopharmacopoeias with caution were considered as an important adaptation strategy. Findings on species and site specific accounts urged further researches on medicinal plants, ethnomedicine, and their interrelationship with impacts of climate change.