Can medicinal use protect plant species from wood uses? Evidence from Northeastern Brazil.

Several ethnobotanical studies have attempted to understand the criteria for the differential use of plant resources. However, we need more effort to understand the interaction between local uses: how using a species for a given purpose may affect its use for another purpose. Thus, we hypothesize that high importance species in a more specialized category of use may have their use reduced for other categories with a more generalist nature. We have conducted the study in three rural communities in northeastern Brazil, set in seasonally dry tropical forest areas. We applied the free-list technique to identify woody species used for medicinal and/or wood purposes (fuelwood, construction and technology). Respondents rated the species according to their efficiency for wood purposes and their local availability. We performed a multiple regression to assess the effects of medicinal popularity, perceived availability, and perceived efficiency for wood uses over the species popularity for wood uses. Our results showed that medicinal use has a significant protective effect against wood uses. Perceived availability and efficiency were significant explanatory variables for wood use. Maintaining the medicinal importance of certain species can be a powerful tool in protecting their populations against more harmful uses.