Medicinal Plants in the Broad-Leaf Mixed Coniferous Forest of Tshothang Chiwog, Bhutan: Floristic Attributes, Vegetation Structure, Ethnobotany, and Socioeconomic Aspects

Abstract

The Himalayan Kingdom of Bhutan, located in one of the global biodiversity hotspots, is endowed with abundant floral wealth, including a wide array of medicinal plants (MPs). However, over-exploitation of these resources is widespread, and only a few studies have assessed the richness and diversity of Bhutanese forests and in particular about the MP resources. A vegetation survey was conducted in Tshothang Chiwog, south-eastern Bhutan to characterize the floristic structure of the broad-leaf mixed coniferous forests with a special focus on MPs. A questionnaire survey involving 40 farmers was also conducted to assess the ethnobotanical and socioeconomic aspects of MP extraction. A total of 157 plant species (38 trees, 19 shrubs, 85 herbs and ferns, and 15 climbers), representing 74 families and 137 genera were identified from the study area, of which 69 species (14 trees, 10 shrubs, 38 herbs and ferns, and seven climbers), belonging to 41 families and 69 genera were medicinally important. The most species-rich families of medicinal plants were: Asteraceae (eight spp.), Apiaceae (four spp.), Polygonaceae, Brassicaceae, Zingiberaceae, and Urticaceae (three species each). Herbaceous flora exhibited the highest diversity (Simpson diversity index, D = 0.97 and Shannon-Weiner index, H ′ = 5.82), followed by trees and shrubs (D = 0.95 and 0.92 and H ′ = 4.86 and 3.97, respectively). All but one herb showed abundance-to-frequency ratio (A/F) ≥0.05, signifying a contagious distribution pattern (large aggregated distribution). Girth class distribution of trees followed an inverse J-shaped pattern. Results of the ethnobotanic study documented 55 MPs. MP collection, as reported by the interviewees, generally improved the socioeconomic status of the people of Tshothang Chiwog. Apart from improving the livelihood security of the local people, aspects relating to health care and culture are also important. Respondents were also concerned about the declining MP wealth of the Chiwog over the years, due to over-exploitation. Monitoring the plant resources and adopting conservation programmes in the Chiwog, in their opinion, may improve the MP wealth of the locality. The lessons learned from the study may have applicability over the south-eastern part of Bhutan and other regions with similar eco-climatic features.

The Diversity of Medicinal Plants of the Himalayan Kingdom of Bhutan

“…Drakpa et al [3] prepared a field guide for the Ugyen Wangchuck Institute for Conservation and Environmental Research with 108 species of medicinal plants found in Bumthang Dzongkhag. Jamba & Kumar [11] published a list of 69 species belonging to 69 genera and 41 families from Tshothang Chiwog, Samdrup Jongkhar, Bhutan. The study was part of the first author's M.Sc.…”

“…A list of medicinal plants along with their uses was prepared, referring to Lama et al [14]; Wangchuk [24], Wangchuk et al [30], Wangchuk et al [29], Wangchuk et al [26], Lakey & Dorji [13], Wangchuk et al [27], Thomas [21], Wangchuk et al [31], Yeshi et al [36], Chetri et al [2]; Drakpa et al [3], Jamba & Kumar [11], Chetri [1]; FoTM [4,5], Penjor et al [16], Wangchuk et al [32]; Tenzin & Tendar [20], Yangzom et al [33], and Nepal [15].…”

Wetland Medicinal Plants of Eastern Himalayan Highlands of Gasa District, Bhutan

“…Ever since the government officially recognized traditional medicines in the country, unsustainable harvesting like poaching and illegal trade of important medicinal plants has taken placed, threatening these plant species [8]. The other common threat includes deforestation, overgrazing, overexploitation, soil erosion, habitat fragmentation, and tourist upsurge [12,6,8,15]. The loss of these plants resources will not only extinct ethno-medical and ethnobotanical practices, but will also affect the health care system and the ecosystem of the nature.…”

“…Reduces fever arising from poisoning and heals wounds, mumps and body swelling[7,34]. Used in eye diseases, diarrhea, jaundice, skin diseases, syphilis, chronic rheumatism, urinary disorders, diabetes, jaundice, gastrointestinal problem [29,35], malaria fever, in relieving pyrexia, as a wash for ulcer sores, as an eye lotion in conjunctivitis [36,37], allays chronic cough and cold[15,34]. Treatment of abscess, boils, malaria, for treatment of insect, snake and bug bites, edema, laryngitis, sore throats, acute tonsillitis, otitis media, in nose bleeding [40], boils, burns, and itches[11,39].…”