Easy Access to Biomedicine and Knowledge about Medicinal Plants: A Case Study in a Semiarid Region of Brazil.

We aimed to evaluate how proximity to urban areas interferes with the relationship between socioeconomic variables and various aspects of medicinal plant knowledge. The study was conducted in six communities of the Catimbau National Park (PARNA Catimbau) in the state of Pernambuco. Eighty participants were interviewed. The communities were divided into two groups according to their distance from the nearest urban center. Socioeconomic data and information on medicinal plants were collected through semistructured interviews. Subsequently, generalized linear models were generated to verify the influence of the interaction between the variables on medicinal knowledge. We observed that proximity to the urban center influenced the relationship between the level of education and the knowledge of body systems treated by medicinal plants. We concluded that environmental variables can generate a differentiated effect on the influence of socioeconomic factors on one's knowledge of medicinal plants.

Local Knowledge and Conservation Priorities of Medicinal Plants near a Protected Area in Brazil.

We investigated the influence of socioeconomic factors (age, gender, and occupation) on the local knowledge of medicinal plants in the Araripe National Forest, Brazil, and the priority of conservation of the species as perceived by people. Additionally, priority species for in situ conservation were identified by calculating conservation priority (CP). Initially, free lists were developed with 152 informants in order to identify the plants known and used by them. Based on the most cited plants in these lists, a salience analysis was performed to identify the ten most prominent tree species. In a second moment, through a participatory workshop, these ten species were classified by the perception of local experts as to their environmental availability and intensity of exploitation. Then, the population size of the forest plant species was quantified through a phytosociological sampling and the conservation priority index (CP) of the species was calculated. A total of 214 ethnospecies were cited by the informants, which were identified in 167 species. Local knowledge was influenced by socioeconomic factors, with positive correlation between age and local knowledge and difference in knowledge among professions. Among the ten most prominent tree species in terms of their medicinal importance, Hancornia speciosa was highlighted as a priority for conservation in the experts' perception because it has low environmental availability and a high exploitation rate. The ten species were ordered by the CP differently from the ordering made by the local experts' perception, indicating that people's perception of species conservation status may not correspond to the actual situation in which they are found in the forests. Conservationist measures based on the perception of informants need complementary ecological studies on the species accessed.

Caryocar coriaceum (Caryocaraceae) diaspore removal and dispersal distance on the margin and in the interior of a Cerrado area in Northeastern Brazil.

The seed dispersal process is a crucial stage in plant regeneration and maintenance of forest biological diversity. While the number of removed seeds is quantitative, the distance to which a seed is removed from its origin is qualitative, because it affects the probability that a seed will germinate and recruit to the next life stage. However, the creation of forest margins can negatively affect the seed dispersal process, especially for large-diaspore plant species. In this study, the diaspore removal and dispersal distance of Caryocar coriaceum, a tree with large diaspores that is in danger of extinction, were analyzed. The study was conducted for two consecutive years in a protected forest in Northeastern Brazil. Each year, 1 200 diaspores with a nylon wire and a satin tape yellow were used and equally distributed in 120 experimental stations established on the forest margin and in the interior. During the first year of the study, no differences in diaspore removal and dispersal distance were found among the investigated environments. However, for the second year of the study, the number of removed diaspores differed significantly; nevertheless, the dispersal distance was not different between the forest margin and the interior. The low diaspore removal percentages suggest that species recruitment may be compromised because the diaspore accumulation close to the relatives enables higher fungi and insect attack. In addition, most of the few removed diaspores were found at short distances from their sources (up to 5 m), which can lead to low genetic variability. Virtually no diaspore was found buried by hoarding rodents, and no diaspore was found preyed upon by these animals. Evidence found in this study suggests the local loss of species dispersers, which can compromise the maintenance of forest biological diversity.

Post-fire regeneration of vegetation on sandy oligotrophic soil, in Itabaiana, Sergipe, Brazil / Regeneração vegetacional pós-queimada em solos arenosos oligotróficos, Itabaiana, Sergipe, Brasil

Two models of post-disturbance regeneration of vegetation in areas of oligotrophic soils have been proposed for temperate regions. The first model is characterized by rapid recovery of the floristic composition, due to the fire resistance of plants; while in the second model, the fire causes extensive mortality and the recovery occurs by recruitment from the seed bank. Since these models have been rarely tested in tropical oligotrophic environments, we applied them in the analysis of floristic compositions in three areas with different post-fire regeneration times in Sergipe State, Brazil. The regeneration followed the seed bank recruitment model in places of bare ground, with a progressive increase in plant density and changes in the relative abundance and dominance of the populations along the successional process. The parameters that best allowed the succession evaluation were the floral similarity, plant height and density, which increased as regeneration progressed. The stem diameter and tillering were inconclusive as parameters for assessing the regeneration progress.

Dois modelos de regeneração pós-distúrbio em vegetação sobre solos oligotróficos têm sido propostos para as regiões temperadas. O primeiro modelo caracteriza-se pela rápida recuperação da composição florística, devido à resistência das plantas ao fogo; enquanto no segundo modelo, o fogo provoca grande mortalidade e a recuperação ocorre por meio do recrutamento do banco de sementes. Uma vez que estes modelos têm sido raramente testados em ambientes oligotróficos tropicais, nós os aplicamos a análises de composição florística em três áreas com diferentes tempos de regeneração pós-fogo em Sergipe, Brasil. Como resultados, identificou-se que a regeneração seguiu o modelo de recrutamento do banco de sementes em locais de solo desnudo, com um aumento progressivo na densidade de plantas e mudanças na abundância relativa e dominância das populações ao longo do processo sucessional. Os parâmetros que melhor permitiram uma avaliação da sucessão foram a similaridade florística, altura e densidade, que aumentou com o progresso da sucessão. Diâmetro do caule e o número de perfilhamentos foram inconclusivos como parâmetros para avaliar o progresso de regeneração.

The ecological apparency hypothesis and the importance of useful plants in rural communities from northeastern Brazil: an assessment based on use value.

The ecological apparency hypothesis in ethnobotanical studies predicts that the apparent plants (i.e., the most easily found in the vegetation) would be the most commonly collected and used by people. To test this hypothesis, it has been used the concept of use value (VU), which measures the relative importance of useful plants for a group of people. However, the use value has got some limitations, including the fact that it does not distinguish "current use" (plants which are effectively used) from "potential use" (well known plants, however not used). Therefore, this study has tested whether the obtained results through three different use value calculations could be useful in testing the ecological apparency hypothesis. These calculations have included the current use value, the potential use value, and the general use value. It has been carried out a vegetation survey and an interview for residents from the rural communities from Barrocas and Cachoeira (Soledade, Paraíba, Brazil). It has been used Spearman's coefficient to correlate phytosociological and ethnobotanical data. It has been observed that phytosociological parameters in Cachoeira were not correlated with any of the use values calculations, except the relationship between the current use value and the relative dominance (r(s) = 0.57; p < 0.05). In Barrocas, every use value calculation was correlated with the basal area and the relative dominance. When each category of use is analyzed separately, it has been observed that there was no correlation between the use value and the phytosociological parameters, except for the construction category, in which the current use value in Cachoeira was correlated with the relative dominance (r(s) = 0.63; p < 0.05), importance value (r(s) = 0.67; p < 0.01), relative frequency (r(s) = 0.71; p < 0.05), and relative density (r(s) = 0.72; p < 0.01). In Barrocas, the UVc for the construction category was correlated with relative frequency (r(s) = 0.69; p < 0.05) and relative density (r(s) = 0.66; p < 0.01). These results have suggested that, the use value calculation, which takes into consideration just the current use of the species, is the one that best fits in the ecological apparency hypothesis.

Dynamics of medicinal plants knowledge and commerce in an urban ecosystem (Pernambuco, Northeast Brazil).

Given the importance of markets and fairs for the commerce of medicinal plants, an ethnobotanical study was undertaken at the Caruaru Fair (Pernambuco, northeastern Brazil) to compare the richness of species sold and their values of relative importance (RI) using two datasets collected with a 4-year interval. The seasonality of these plants' supplies was also analyzed. The Caruaru Fair is located in the 18 de Maio Park. It covers an area 40,000 m(2) and is used by merchants who sell several types of products, such as supplies, handicrafts, clay and aluminum utensils, shoes, clothes and medicinal plants. Semistructured interviews were carried out with the vendors who agreed to take part in the study in order to record which plants were sold and their respective indications. The plants were collected, and the species were determined. The information was analyzed with quantitative tools. A total of 169 plants were identified from both surveys, which were significantly different with regard to species richness (p < 0.05) but did not vary in relation to species' Relative Importance (p > 0.05). In relation to the seasonality of the plant supply, habit may explain the lack of some species during certain periods of the year, as most of the absent plants are herbaceous. In terms of the species most sold locally, it was found that spontaneous tree species are well known and extensively commercialized.

Bark regeneration and tannin content in Myracrodruon urundeuva Allemão after simulation of extractive damages--implications to management.

Due to the current exploitation and consequent extinction of native medicinal plants around the world, new strategies have been proposed to address the sustainable use of this resource. Accordingly, the goal of this study is to assess the speed of bark regeneration of Myracrodruon urundeuva Allemão and to compare the tannin content before and after tissue regeneration. Twenty individuals from an area of Caatinga in Caruaru, Pernambuco State (NE Brazil), were selected. To evaluate the speed of bark regeneration, four treatments were established, according to the area of bark removed (10 × 2, 6 × 5, 8 × 5 and 10 × 5 cm), with five replicates (five individuals of M. urundeuva Allemão) and three treatments of tannin content (bark removed before damage, as regenerated tissue, and non-impacted bark or control). At the end of 23 months of monitoring the regeneration, we found that only seven of the 20 individuals analyzed did not fully heal. No significant correlation between the monthly percent regeneration and average monthly precipitation was found. The tannin content varied according to the quantified tissue (after damage, regenerated and control) as well as between damage classes (20 cm(2)-41.64 to 63.53 mg; 30 cm(2)-49.25 to 67.54 mg; 40 cm(2)-31.69 to 67.44 mg; 50 cm(2)-34.08 to 48.53 mg). Despite the variations found, there was no significant difference between the measurement periods (p > 0.05) or damage classes (p > 0.05). The results showed that the regeneration rate was higher in individuals belonging to the 10 × 2 and 10 × 5 cm groups and that there is no correlation between precipitation and regeneration speed. Tannin levels did not vary significantly in the tissues before damage and after regeneration.