Environmental heterogeneity influences plant resource use - A case study in a rural community of NE Brazil.

In regions of high environmental heterogeneity, it is important to observe if different landscape units are used differently by human populations, which can have consequences for the conservation of these units. Thus, the present study seeks to answer the following questions: (1) are different native vegetation units used for different purposes by the local population? (2) is there a difference between the conservation status of native vegetation units according to the local perception? The study was implemented in the rural community of Morrão de Cima, in the municipality of São Desidério (Northeast Brazil). Data were collected through semi-structured interviews and participatory workshops. The main native vegetation units recognized by the interviewees were Brejo, Mata Seca, Serra and Chapada. The community uses the different units of native vegetation for different purposes. The extraction of medicinal resources was important in the Chapada, while the exploitation of food resources was important in the Brejo, and the collection of wood resources was more substantial in Mata Seca and in Serra. We also found differences in the perceived conservation status of the native vegetation units. Our findings indicate the need of caution when proposing conservation strategies in heterogeneous environments, since each landscape unit may be undergoing specific processes, requiring different strategies.

The use of different indicators for interpreting the local knowledge loss on medical plants

ABSTRACT The increasing loss of local ecological knowledge may have negative impacts on the resilience of socio-ecological systems and may also negatively impact bioprospecting efforts, since local ecological knowledge is an important source of information for searching new drugs. Recent studies try to evaluate whether communities are experiencing loss of local ecological knowledge. However, some of them make conclusions which are erroneously based on specific analyses of a single indicator. We propose an integrative analysis of three indicators, namely: number of plants cited by young people and elders, therapeutic choices and people's connectance in terms of medicinal plant learning. The study was carried out in the community of Sucruiuzinho (Bahia, Brazil). We conducted semistructured interviews and a therapeutic recall with 24 local dwellers. We did not find evidence of local ecological knowledge loss in the studied community. Although younger people know fewer plants, they are well connected in terms of knowledge transmission. Moreover, in illness events, young people and adults have similar proportions of choice for plants when compared to allopathy. Concomitant use of the three indicators leads to a more realistic scenario of local ecological knowledge loss than the use of only one of them.