Traditional knowledge in medicinal plants and intermedicality in urban environments: a case study in a popular community in southern Brazil

Background: Ethnobotanical studies have demonstrated the ability of different social groups to maintain and diversify plant knowledge in urban environments. This study characterizes the traditional knowledge about medicinal plants in a popular community in Porto Alegre metropolitan city, Brazil. Methods: Semi-structured interviews were carried out with 28 people, four of whom were healers. Data were collected regarding the uses, ways of obtaining the plants, the origin of the interviewees and their knowledge. The mentioned species value of relative importance was calculated. Relationships between traditional and scientific medical knowledge (intermedicality) were characterized and discussed. Results: The study identified a total of 237 plant species, most of them native to Brazil. The family with the highest number of representatives was Asteraceae (38), followed by Lamiaceae (17). Native and ritualistic species showed high values of relative importance. The main form of learning found was vertical, with mothers and grandmothers being the main ones responsible for teaching. Traditional knowledge is influenced by scientific medical care practices and the most significant use of herbs refers to the digestive system, followed by the respiratory system. The collection is the leading way of obtaining the plants. Conclusions: The high number of species used, and the substantial knowledge repertoire, reflect the local sociocultural and environmental diversity and the vital role of women and healers in producing and transmitting this knowledge. Deepening ethnobotanical studies with healers and women is a way of enhancing traditional medicines in urban environments. Keywords: urban ethnobotany, ethnomedicine, native species, ritualistic use, urbanization