A history of change: causes of miombo woodland decline in a protected area in Malawi.
Abstract
Analysis of aerial photographs showed measurable conversion of closed canopy miombo woodland to sparse woodland (<50% canopy cover) during 1982-90 at Chembe and Msaka villages within Lake Malawi National Park. A study was conducted during 1993-94 to investigate the possible contributions to these changes by local use of domestic fuelwood, construction poles and fuelwood for commercial fish smoking. Domestic fuelwood use was measured in 30 households over an 11-month period, domestic fuelwood comprising mainly of dead wood and small branches over a wide species range. Mean total annual domestic fuelwood consumption by the total enclave population was less than half the mean annual production of fallen dead wood in the Park, estimated from 3 quadrats harvested monthly over the same period. Construction poles were mostly small and came from a broad species range. Eucalyptus trees were commonly grown for poles. Construction pole use was sustainable and showed signs of substitution. The 305 commercial fish smoking stations in the enclaves used less fuelwood annually than domestic fuelwood users. However, the men who undertake this activity target large branches and logs from a narrow species range, involving destructive felling of canopy species. 95% of men collecting fuel for fish smoking used cutting tools and the scale, size classes and species involved indicated that this activity may drive the observed degradation of closed canopy to sparse woodland. Commercial fish smoking was introduced relatively recently by immigrants, along with gill netting that harvests larger fish requiring smoking for preservation. Currently, management targets and penalises domestic fuelwood collectors, but it is concluded that while seeking to reduce demand and provide alternative fuelwood sources, law enforcement and forestry extension should be re-orientated to address the extraction of fuelwood for fish smoking.