Charcoal Production Drives Forest Degradation and Biodiversity Loss in a Miombo Woodland: Insights from Mwekera National Forest Reserve, Zambia

Abstract

This study evaluated the ecological impacts of charcoal production on forest structure and species composition in the Mwekera National Forest Reserve, a representative miombo woodland in Zambia’s Copperbelt Province. Thirty systematically established plots (20 m × 20 m) were surveyed to assess species richness, diversity, evenness, and structural attributes. A total of 54 woody species were recorded, with a Shannon–Wiener Diversity Index (H') of 3.313 (effective species number = 27.463) and Pielou’s Evenness Index (J') of 0.855, indicating moderate diversity and relatively even species distribution. Despite this, results showed a marked decline in the dominant miombo genera, Brachystegia, Julbernardia, and Isoberlinia, which were selectively harvested for charcoal. In some plots, these species were entirely absent, reflecting intense harvesting pressure. Larger trees, particularly those with greater diameter at breast height (DBH) and height, were disproportionately removed, as indicated by a strong positive DBH–height correlation. Consequently, the residual forest is increasingly dominated by smaller, less valuable trees, leading to simplified structure and reduced biodiversity. The study concludes that unsustainable charcoal production significantly alters miombo composition and weakens ecosystem resilience. It recommends research on soil and faunal impacts, promotion of alternative livelihoods, and strengthening of community-based forest management to curb degradation.