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Abstract: Satellite remote sensing offers a cost‐effective method for monitoring fire occurrence in savannah systems, for proper fire management. However, the ability of satellite fire products to detect active fire is known to vary depending on the terrestrial ecosystems and sensor characteristics. In this study, the overall accuracy, kappa coefficient of agreement and true skill statistic (TSS) were used to assess the accuracy of two MODIS fire products (MOD14A1 and MCD14ML) to detect active fire at two savannah woodland sites dominated by Baikiaea plurijuga and Brachystegia spiciformis in Zimbabwe. In both sites, MOD14A1 with a coarse spatial resolution of 1 km had a poor index of agreement with ground fire data (kappa = 0, TSS = 0 and overall accuracy ≤ 0.4). By contrast, a moderate to strong agreement between MCD14ML and active fires measured on the ground was observed at both study sites (overall accuracy ≥ 0.7, kappa ≥ 0.6 and TSS ≥ 0.6; Table  ). It was therefore concluded that MCD14ML, with a spatial resolution of 375 m, is a more suitable product for detecting active fires in both Baikiaea plurijuga and Brachystegia‐dominated savannah woodlands of southern Africa compared to MOD14A1. [ABSTRACT FROM AUTHOR]

Some imported guitars and others made in Zambia exhibit poor sound quality and properties. Zambia grown timbers were evaluated for their suitability as tonewoods. Pinus kesiya was suitable for soundboard as it had brighter appearance and best radiation coefficient 7.3 m4 s-1 kg. Its lower impedance 2733 Nmm2 s m3 gives better sustain. Pterocarpus angolensis was used for the back and sides as it was very stable, volumetric shrinkage 5.4%, and low impedance, 2,298 Nmm2 s m3 which reduced loudness. This species was also used for the neck. Baikiaea plurijuga was employed in fretboard and bridge construction as it was appreciably hard with Brinell hardness rating of 6.05 kN. A guitar made using the selected timbers was tested qualitatively. The Reference and the Experimental guitar attained the same score demonstrating improvements attributable to systematic wood selection. The study established that the quality of locally made guitars could be improved significantly if luthiers adopt appropriate wood selection criteria. [ABSTRACT FROM AUTHOR]

Communal households in Zimbabwe are no different to other areas of the developing world when it comes to harvesting natural forest resources. A range of forest resources is harvested from protected forests and woodlands for direct home consumption and for sale. In Zimbabwe only a few studies have attempted to describe and characterise the dynamics of forest product use by communities living adjacent to protected forests. This study was conducted in the Baikiaea plurijuga forests in Fuller Forest, western Zimbabwe, protected since 1943. The study explored the characteristics and dynamics of forest resource use by communities surrounding this protected forest. Results indicated that all households, rich and poor, were harvesting at least some forest resources from the protected forest. The most frequently harvested resources being firewood, wood for curios, thatch grass, wild fruits, timber for construction and fencing and those who owned livestock used the forest for livestock grazing. The extraction and use of 23 different products was recorded across five villages. The top five harvested forest products in terms of the mean proportion of households using them were fuelwood, building poles, thatch grass, wild fruits and broom grass. Forest products were harvested both for own consumption and for sale. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize hollows found in selected tree species (in Cawston Ranch in Zimbabwe) as a potential habitat for small mammals because cavities are important as resources for wildlife: for foraging, shelter, roosting and nesting purposes. Four vegetation types were chosen for analysis: Baikiaea plurijuga, Colophospermum mopane, Combretum molle and Commiphora mollis according to abundance and dominance in the plots they occurred. Transect sampling was done to collect vegetation data. The total number of living trees and stags were recorded in each plot. Trees in a plot were thoroughly inspected for hollows. The following dimensions were measured on cavity trees: hollow size (diameter), hollow location and diameter at breast height. The results indicate that the rate of hollow formation and utilization is significantly dependent on tree species. There was a significant difference in the provision of hollows in stem and crown of a tree in each of the vegetation classes analysed. B. plurijuga hollows had the highest utilization whilst C. molle had the least utilization. Hollows are utilized irrespective of their location as long as the animal finds a niche, and stags at advanced stages of decay are not important in providing habitats for animals. [ABSTRACT FROM AUTHOR]

Human-induced fires are a major disturbance in Baikiaea plurijuga woodland savannas that are economically important for timber production. Most fires occur during the late dry season, when they may severely damage woody plants. Prescribed burning during the early dry season is a management strategy to reduce fuel loads and thus the incidence of intense fires during the late dry season. There is, however, little information on fire behaviour characteristics of early dry season fires. We studied the relationship between experimental fuel conditions and fire behaviour by lighting 15 fires during the early dry season in a Baikiaea woodland. Fire intensity ranged from 25 to 1341 kW m-1, while rate of spread of fire varied between 0.01 and 0.35 m s-1. Fire intensity and rate of spread were positively related to flame height, leaf-scorch height and proportion of the area burnt. The relationships suggest that fire characteristics can be retrospectively determined using a variable such as scorch height. The grass fuel load, wind speed, relative humidity and to a lesser extent fuel moisture were important predictors of rate of spread, flame height, leaf-scorch height and proportion of the area burnt, with no impact due to the lifter fuel load. The grass fuel load and wind speed had a positive effect on rate of spread, whereas relative humidity and fuel moisture had a negative effect. These findings indicate that managers can predict the likely damage to woody plants during an early dry season burn by assessing the grass fuel load and weather conditions at the time of burning. [ABSTRACT FROM AUTHOR]