Browsing by Author "Ernest, S"

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Characterization of some typical soils of the miombo woodland ecosystem of Kitonga Forest Reserve, Iringa, Tanzania: physico-chemical properties and classification
(Sokoine University of Agriculture, Tanzania., 2014-03) Shelukindo, H. B; Msanya, B; Mwangoli, S; Ernest, S; Munishi, P; Singh, B
Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanzania. The current study was carried out to map and classify soils of Kitonga Forest Reserve, which is a typical miombo woodland ecosystem, in order to generate relevant information for their use and management. A representative study area of 52 km2 was selected and mapped at a scale of 1:50,000 on the basis of relief. Ten representative soil profiles were excavated and described using standard methods. Soil samples were taken from genetic soil horizons and analyzed in the laboratory for physico-chemical characteristics using standard methods. Using field and laboratory analytical data, the soils were classified according to the FAO-World Reference Base (FAO-WRB) for Soil Resources system as Cambisols, Leptosols and Fluvisols. In the USDA-NRCS Soil Taxonomy system the soils were classified as Inceptisols and Entisols. Topographical features played an important role in soil formation. The different soil types differed in physico-chemical properties, hence exhibit differences in their potentials, constraints and need specific management strategies. Texture varied from sandy to different loams; pH from 5.1 to 5.9; organic carbon from 0.9 g/kg to 20 g/kg; and CEC from 3 cmol/(+)kg to 24 cmol/(+)kg. Sustainable management of miombo woodlands ecosystem soils requires reduced deforestation and reduced land degradation.
Height-diameter allometry for tree species in Tanzania mainland
(Hindawi, 2019-02) Mugasha, W A; Mauya, E W; Njana, A M; Karlsson, K; Malimbwi, R E; Ernest, S
Total tree height (H) and diameter at beast height (D) are important independent variables in predicting volume, biomass, and other forest stand attributes. However, unlike D measurement, which is easy to measure with high accuracy, H measurement is laborious. This study, therefore, developed H-D relationships for ten different forest types in Tanzania Mainland. Extents in which climate and forest stand variables explain the variation in H-D allometry were also assessed. A total of 31782 sample trees covering miombo woodlands, humid montane, lowland forests, bushlands, grasslands, mangroves, cultivated land, wetlands forests, and pines and Eucalyptus species plantations were used for model development. The H estimating model without climate and forest stand variables referred herein as “base model” was first developed followed by “generalized model” which included climate and stand variables. All the data were fitted using nonlinear mixed effect modelling approach. Results indicated that generalized H estimating models had better fit than the base models. We therefore confirm a significant contribution of climate and forest structure variables in improving H-D allometry. Among the forest structure variables, basal area (BA) was far more important explanatory variable than other variables. In addition, it was found that the mean tree H tends to increase with the increase of mean precipitation (PR A ). We therefore conclude that forest specific generalized H model is to be applied when predicting H. When forest type information is not available, generalized regional model may be applied. Base model may be applied when forest stand or climate information are missing.
Nicotine contents in honey from tobacco and non tobacco growing areas in Kigoma region, Tanzania
(Tanzania Forestry Research Institute (TAFORI) and Tanzania Forest Fund (TaFF)", 2018) Balama, C; Kagosi, P; Tewele, C; Mbwambo, L.; Laswai, F; Msalilwa, U; Ernest, S
Nicotine content in honey is currently the major issue of concern to honey quality in Tanzania. This study was carried out to determine nicotine content in honey from tobacco and non-tobacco growing areas in Kigoma Region, Tanzania. Specifically, the study determined nicotine contents in honey and bee fodder samples. Fresh honey samples were collected from beehives within tobacco and non-tobacco growing areas and from vendors for laboratory tests. Results showed that nicotine content in the fresh honey which was collected from beehives located within tobacco growing areas is significantly higher than that collected from non-tobacco growing areas (0.46µg/g vs. 0.26µg/g, p <0.05). The honey samples from vendors in town and villages had nicotine contents of 0.41µg/g and 2.98µg/g, respectively. It was observed that most of the bee fodder tree species in Miombo woodland had traces of nicotine. Among the most important bee fodder tree species with the highest amount of nicotine were Brachystegia spiciformis (20.966µg/g), and Julbernardia globiflora (13.168µg/g). Meanwhile Vernonia colata, Combretum collinum and Combretum mole had the lowest nicotine contents of 0.836µg/g, 0.006µg/g, and 0.004µg/g, respectively. Generally, honey samples which were collected from all sources contained different amounts of nicotine. However, these contents were perceived to be tolerable for human health. The sampled bee forage tree species were also observed to have nicotine, which is associated with nicotine in the honey. The study recommends for the establishment of the national standards indicating the allowable amount of nicotine in honey for human consumption. Further research needs to be done in other areas and vegetation types in order to address this concern country- wise