Effect of artisanal gold mining on woody plant diversity in Western Burkina Faso

Abstract

Although artisanal gold mining strongly contribute to enhance people incomes in West Africa, this activity can lead to habitat fragmentation and loss of woody species. Therefore, studying the impact of artisanal gold mining on woody plant diversity is needed for efficient management of forest resources. In this study, we investigated the impact of artisanal gold mining on woody plant diversity and dynamics in the Kari classified forest in Western Burkina Faso. Forest inventories were carried out at two sites including a gold panning site and a control site, following a systematic sampling design. We identified all woody species and measured all woody species with a diamtere at breast height ≥5 cm. A total 60 plots of 900 m² were surveyed. Diversity indices and dendrometric parameters were calculated and compared between the two sites. The results showed a higher species richness (59 woody species distributing in 39 genera and 18 families) in the control site compared to the gold panning site (38 species distributing in 25 genera and 12 families). The mean values of the number of species per plot and the Shannon diversity index were higher in the control site (15.50 ± 8.80; 2.16 ± 0.43, respectively) than in the artisal mining site (5.47 ± 2.71; 1.40 ± 0.53, respectively), showing that the control site is more diverse than the site that is under gold panning. The control site also had the highest density (683.33 ± 262.99 ft/ha) and stable woody stands compared to the less gold panning site (137.41 ± 102.31 ft/ha) where unstable woody stands were found. While the gold-panning site was characterised by biophysical impacts such as destruction of the plant cover and soil excavation, no visible impact was observed at the control site.Theses findings highlight the negative impact of artisanl gold mining on woody species diversity and structure. The study provides essential information for decision-making on sustainable forest management in the context of mining boom in Burkina Faso's.