A survey of medicinal plants in BaVi National Park, Vietnam: Methodology and implications for conservation and sustainable use

Conservation of medicinal plant resources is a critical ecologic, cultural and economic issue in Vietnam, as with other parts of South-east Asia, and the tropics and sub-tropics generally. The paper describes the development and application of a survey methodology, using standard phytosociological techniques, for the quantitative inventory of medicinal plants in BaVi National Park, northern Vietnam. One hundred and twenty-six permanently marked transects, each 50 × 10 m, were established over the ranges of altitudes and characteristic vegetation structural types present in the Park. Over 200 medicinal plant species used by Dao people were sampled (of a documented total of about 300 species including introduced species grown in home gardens), in vegetation types ranging from closed evergreen forest at high altitude (> 1000 m), through secondary forest formations, bamboo thicket, open grassland and plantation, distributed generally along a declining altitude gradient. Forty-one of 44 economically important medicinal species were sampled also. Important medicinal plant species, half being vines, were concentrated particularly in more-or-less intact, late secondary closed forest habitats at higher elevations. The status of most important medicinal plant species was found to be rare or uncommon, and to exhibit scattered (as opposed to clumped) distributions. The paper discusses implications of the applied methodology and the assembled data for the inventory, conservation, and sustainable use of medicinal plants at local and broader regional scales.