Conservation of medicinal plants for managing HIV/AIDs opportunistic infections in Rungwe district, Mbeya region, Tanzania.

Abstract

The application of medicinal plants in primary health care for people living with HIV/AIDS is well acknowledged in Tanzania. However, the conservation status of medicinal plants is questionable. This study aimed at assessing the conservation status of medicinal plants used to manage HIV/AIDS opportunistic infections in Rungwe District, Mbeya Region, Tanzania. Specifically, this study sought to: identify and document medicinal plant species used to manage HIV/AIDS opportunistic infections in the study area, explore indigenous knowledge of conserving medicinal plants in the study area, assess the wild population status of medicinal plant species used to manage HIV/AIDS opportunistic infections and to propose a conservation framework for medicinal plant species in the study area. This study employed a cross sectional research design through which data were collected at a single point in time. Ethnobotanical data were collected using questionnaires, key informants’ interviews, focus group discussions and field observations. Furthermore, the inventory was conducted to collect data on the wild population status of priority medicinal plant species. While quantitative data were analysed using descriptive and inferential statistics, qualitative data were analysed using content analysis method. Logistic regression models were developed to analyse the influence of socio-demographic factors of the respondents on ethnobotanical knowledge. Preference ranking method was used to obtain priority medicinal plant species used to manage HIV/AIDS opportunistic infections in the study area. Analysis of inventory data was done by using Microsoft Excel and QGIS software version 2.18 to analyse spatial data gathered on assessment of wild population status of priority medicinal plant species. Inventory data were further analysed for species structure and density. It was revealed that a total of 31 medicinal plant species belonging to 23 families were used to manage HIV/AIDS opportunistic infections in the study area. Compositae and Rosaceae were themostly extracted plant families (15%). With regards to plant parts, the study indicated that leaves were mostly extracted for medicine (44%) than others. Of the cited HIV/AIDS opportunistic infections, Tuberculosis utilized the largest share of the medicinal plant species (60%). The ethnobotanical knowledge of the respondents was independent of age and sex, but was significantly influenced by ethnic background and education levels of the respondents (p=0.00). In relation to indigenous knowledge on conservation, the study indicated that up to nine indigenous conservation practices were recorded. Out of the nine indigenous conservation practices, selective harvesting was the most popular to 94% of the respondents. Moreover, the study revealed that indigenous knowledge on conservation was significant among males than females (p=0.031) and adults than youth respondents (p=0.002). The study revealed up to seven priority medicinal plant species used by communities to manage HIV/AIDS opportunistic infections in the study area. The assessment of the wild population status of medicinal plant species was carried out on two species (Hagenia abyssinica and Myrica salicifolia). The findings on population status of priority medicinal plant species indicated that, both species were mostly distributed within 1950-2050 meters above sea level in the Poroto forest reserve and were linearly distributed adjacent rivers. The population structure of priority medicinal plant species showed J-shaped curves, most species were dominant in (>10cm) size class and few in the lowest size class (<10cm) for Hagenia abyssinica while there were no species of the lowest size class found for Myrica salicifolia. With regards to stem density, the findings revealed that Hagenia abyssinica had a total of 200 stems/ha whereas only 28 stems/ha density were found in Myrica salicifolia. Further, it was indicated that arable farming, logging, and animal grazing inside the forest reserve interfered the sustainability of medicinal plant species. To address those conservation challenges the respondents suggested approaches such as ex-situ (32%) and in-situ (23%). The findings from all objectives were scrutinized to arrive at proposing aconservation framework suitable for medicinal plant species. The aim of the conservation framework is to attain sustainability of medicinal plants and ensuring improvement of health of the people. The framework proposed encompasses many variables such as: legal and institutional frameworks ex-situ and in-situ conservation and conservation knowledge (formal and/or indigenous). Other variables include suitable site selected for ex-situ conservation from which the properly prepared seeds/seedlings will be planted. With regards to in-situ conservation, it is required that seedlings for restoring the wild are properly prepared and they are left to grow under proper managed and protected environment. In conclusion, the communities in the study area are rich in ethnobotanical knowledge. This study recommends for preservation and transmission of ethnobotanical knowledge across generations by the elders to the youth. Based on the study findings, there is a necessity of taking urgent measures to address conservation challenges and safeguarding the medicinal plant species. The implementation of the proposed conservation framework requires government’s responsible institutions such as the Tanzania Forest Service Agency (TFS), Tanzania Forest Research Institution (TAFORI) together with academic and other research institutions, environmental policy makers and conservationists, local authorities and all stakeholders interested in the medicinal plants sector to work cooperatively.