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Ghana's economic development relies largely on the mining industry, but the ecological cost is very high, particularly for the small-scale sector. To ascertain and give an account of the ecological pressures from the small-scale gold mining sector, we quantified and appraised the ecosystems (land cover types) degradation due to mining land use along portions of the renowned Pra River basin of Ghana. The study classified and analysed high-quality Landsat image data to monitor processes and changes in the river basin and adopted the Ecosystem Service Value (ESV) model to quantify the forgone value in monetary term. The results revealed that the initial ESV of 17.69 million US$ in 1986 increased to 18.40 million US$ in 2002 for the study landscape with the small-scale mining sector accounting for 8.4% of the trade-off costs. The expansion of forest areas and its higher value coefficient (VC) was, however, prevalent and this resulted in a net positive change during this period. However, in 2016, out of the total ESV of 14.63 million US$ obtained, the small-scale mining activities accounted for 36.8% of the trade-off costs. The substantial increase in trade-off costs with a subsequent decrease in ESV in the study landscape, following the intensification of small-scale gold mining, indicates that their activities have been degrading the watershed ecosystem and are, therefore, unsustainable. The study affirms the need for policymakers/government to review the laws, particularly on post-mining monitoring schemes to deter illegal miners and support the registered small-scale miners who are willing to implement land rehabilitation activities.

Climate change represents a major potential threat to the viability of rural households’ livelihoods in sub-Saharan Africa. This study focused on the perceptions of climate change and adaptation strategies of local cotton farmers in Côte d'Ivoire, identified as particularly vulnerable to climate change. A survey was conducted among 355 smallholder farmers distributed in four departments of the cotton basin of Côte d'Ivoire (Korhogo, Boundiali, Ferkessédougou and Mankono). Using changes in weather pattern as indicators of climate change, the results showed that majority of respondents believe climate change is evident in the study area and has negative effects on their livelihoods. Respondents reported an increase in temperature and decrease in rainfall amount in Korhogo and Boundiali departments, which were consistent with the climate data. The main coping strategies implemented by the farmers were shifting of planting dates and timing of cultural activities, adopting new crop varieties, ploughing before planting, diversifying crops and making specific sacrifices to divine powers depending on the type of belief of the farmer. The farmers’ adoption of adaptation strategy depended on their perception of climate change and the available coping strategy. Lack of sufficient knowledge and government support were the major constraints that hindered cotton farmers to adapt effectively, leading to low cotton productivity in the study area. Therefore, policy implications will be crucial to help farmers make better adaptation choices in the face of climate change.

The role of forest plantations in carbon sequestration and biodiversity conservation is a topical issue among researchers and policymakers globally. This study compares understorey floristic diversity and carbon stock of a 15-year-old monoculture Tectona grandis plantation under intensive and poor management in a dry semideciduous ecological zone of Ghana. The study employed a nested plot design with twelve (12) 50 m × 50 m plots laid at 50 m intervals along a diagonal line transect on both study sites for the sampling of Tectona grandis trees. Understorey trees, shrubs, and climbers were sampled within 10 m × 10 m subplot, whilst grasses and herbs were sampled within 1 m × 1 m quadrats. The study revealed a significantly higher understorey species diversity in the intensively managed plantation (Shannon index; species richness) compared with that of the poorly managed plantation. Similarly, total biomass (189.80 ± 1.846 Mg/ha) and carbon stock (94.90 ± 0.92 Mg C/ha) in the intensively managed plantation were observed to be significantly higher than the poorly managed plantation (biomass: 138.54 ± 3.70 Mg/ha; carbon stock: 64.27 ± 1.85 Mg C/ha), whiles the species composition between the two sites was different (Sorenson’s similarity index: 0.47). The study, therefore, concludes that silvicultural forest management interventions improve the understorey floristic diversity and carbon stock in monoculture plantations. Consequently, the study recommends the adoption of silvicultural interventions in plantation management in Ghana to improve their contributions to carbon sequestration and floristic diversity conservation.

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