Assigning Medicinal Plant Value and Estimating Traditional Environmental Knowledge in Ghana, Africa Using Ethnobotanical Measures.

Abstract

Over the past 15 years, the West African country of Ghana has lost roughly 25% of its forest cover, leading to a decline in both traditional environmental knowledge and species. This research contributes to the literature by exploring how to best assess knowledge loss and identify important species that provide incentives for conservation. I apply and evaluate ethnobotanical measures to meet the objectives of 1) documenting knowledge of medicinal plants, 2) identifying the most locally important medicinal plants, and 3) assessing current level and distribution of traditional plant knowledge. I assign plant importance by several measures (including frequency cited, number of uses, and informant consensus), while developing and testing three new applications of the informant consensus method.

Medicinal plant knowledge is well established in the area, and identified important plants are confirmed by literature as being effective. There is no difference between sexes or ages in the number of medicinal plants named (suggesting little knowledge loss), but there is a difference in which species are named (suggesting knowledge change and potential for future losses). Accessibility to and use of western medicine drives the traditional knowledge loss, and thus, I recommend the encouragement of sustainable use to conserve knowledge. An informant consensus measure, which uses a logarithmic function to assign value to plant use, is identified as the most appropriate estimator of plant importance.