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The genesis and characteristics of the gold mineralisation in the area between river Malaba and river Solo in Busia district, South Eastern Uganda.

(Makerere University, 2005-07) Mbonimpa, Alex

The present study was carried out in Busia district, in eastern Uganda and covered an area of about 100 km2. It involved rock, soil and stream sediment sampling and field observations (e.g. structures, terrain, etc.). The area has two types of gold deposits: quartz vein-hosted deposits and Banded Iron Formation (BIF) -hosted deposits. In the BIF-hosted deposit type, no ore minerals are visible to the naked eye and any gold mineralisation therein is perhaps disseminated. Thin section studies show that the rocks in the area are metabasalts, quartz diorites, quartz monzodiorites, monzodiorites, monzogranites syenogranites and banded quartzites (BIF). Polished sections of the quartz vein-hosted type were also studied by reflecting microscope and Electron Microprobe (EMP). The main ore minerals are pyrite, magnetite and ilmenite but pyrrhotite, chalcopyrite, covellite, galena and rutile are also present. EMP analyses of ore minerals indicate that gold in the Busia quartz vein deposits occurs as electrum or native gold inclusions in pyrite with fineness in the range of 451 – 863. It also occurs as invisible gold in the sulphide minerals. Pyrrhotite has the highest values of invisible gold (up to 4.33 wt % Au) but its volume proportion is insignificant. Invisible gold in pyrite however may contribute significantly to the total gold budget of the Busia quartz vein deposits since pyrite is abundant. Fluids intruding the basaltic country rocks through NW-trending fractures led to the formation of the quartz veins and the precipitation of the sulphides and the gold. This points to an epigenetic origin for the quartz vein hosted mineralisation. The Buteba granite is unlikely to be the source of the mineralising fluids. Isotope/ REE studies and age determination of the mineralisation need to be done to determine the genesis of the mineralising fluids. Stream sediment, soil and rock samples were analysed chemically by AAS and XRF methods. Of the three areas proposed for follow-up by Mroz et al. (1991), the Tira area has the first priority soil anomaly (up to 4.8 ppm Au) followed by the Osapiri area (up to 2.8 ppm Au). Stream sediment anomalies are found on rivers Nakola, Tira and Aget. Generally, the stream sediments have higher gold concentrations (up to 38.6 ppm Au) than the soil samples. Lead shows the distribution most similar to that of gold in the rock, soil and stream sediment samples and so is the best indicator element for gold.
Biomass and hydropower potential and demand in the Uganda Albertine Rift Region

(Makerere University, 2006-08) Cisirika, Katcho Karume

This study assessed the hydropower potential in the Albertine Rift Region and suggested electricity as an alternative to reduce the pressure on biomass. Hydrological and topographical conditions of the region were analyzed in GIS environment, in order to identify potential hydropower sites. River flow measurements were used to estimate capacity of each site in power generation. A total of 51 potential sites were identified with an aggregate minimum potential (river runoff) power generation capacity of 896 MW. This study also assessed the current trend of biomass consumption in Uganda Albertine Rift Region, and explored possible solutions for sustainable development of these resources in the future. The biomass trend was first assessed by analyzing satellite images (a total of 45 satellite images) for the years 1984, 1990 (taken as control point), 1995, 2000, and 2003. Results showed that under current conditions, Ugandan Rift Region biomass consumption rate may induce depletion of the resource to the minimum value around 2018. Sustainable resource management constraints biomass consumption to be proportional to the production before 2006 up to 2020 and constant afterwards. The biomass dynamics was investigated by solving Schaefer’s model improved by Holling’s model for Uganda Albertine Rift Region conditions, assuming that in absence of harvesting and at low densities, the biomass resources grow at the intrinsic rate. When the stock is at equilibrium, the surplus production is basically cut, while if the stock is growing, surplus production is consumption plus net growth of the biomass resource. Moreover, the behaviors of the consumers of the Ugandan Albertine Rift region biomass do mimic two effects proposed in the Supruce Budworm model with the use of Holling’s type III consumption equation. First, they tend to increase their dependence on the forests when the forest density increases and also the population of people depending on forests seems to grow when the forest densities increase. Holling (1959) disc equation assumes the principle of time budget, that is, consumers spend their time on two major activities; namely, searching for desirable species and processing their harvest. This equation was used to develop a model for the dynamics of biomass in the Uganda Albertine Rift Region. To avoid overdependence on biomass, a deliberate policy needs to be strengthened to take advantage of the abundant hydro-potential in the districts and other renewable energies. A shift in the present energy matrix towards renewable energy sources and measures to improve energy efficiency will greatly contribute to solving a broad range of issues. The low cost of some Small Hydropower schemes may prove more economic than extension of the existing Uganda national electric grid to isolated areas like in Uganda Albertine Rift Region. Liberalization policies should be encouraged so that the private sector is more involved in energy production and delivery. These hydropower plants are relatively cheap to develop in international terms. Key words: Biomass, consumption, growth rates, land-use, Uganda, environment, dynamics, hydropower, energy.
Earthquake data files

( 2006-09) Batte, Arthur Godfrey
Development of an appropriate solar radiation model for Uganda

(Makerere University, 2006-09) Mubiru, James

Sizing of solar energy systems is necessary in order to optimize their output. This requires a database of solar radiation for locations for which the systems are being assessed. Solar radiation data is also required in modeling a building’s thermal performance, as input into ecological and crop models and evaluation of long-term effects of climatological changes. Solar radiation data can be provided through measurements. In Uganda, measurements of total solar radiation and its two components (diffuse and direct) have been carried out for a few locations, such as in Kampala, Entebbe and Gulu. It is difficult to have measurements from all locations of interest because the measuring instruments are expensive to purchase and install. An alternative to obtaining solar radiation data is to estimate it either by use of an appropriate solar radiation model or interpolation of the few existing records. Interpolation results into solar radiation maps. This study had an overall objective of developing an appropriate solar radiation model for Uganda. This was achieved through measurement of diffuse and direct solar irradiation and subsequent computation of total solar irradiation at four selected locations in Uganda; investigation of relationship between total, diffuse, direct solar irradiation and a selection of meteorological and geographical parameters, which lead to an appropriate solar radiation model for Uganda; prediction of total, diffuse and direct solar irradiation using this model; interpolation of measured and predicted total, diffuse and direct solar irradiation and subsequent drawing of solar radiation maps for Uganda. The uncertain nature of solar radiation and the modeling abilities of Artificial Neural Networks (ANN) have inspired the application of ANN techniques to predict solar radiation. ANN are intelligent systems that have the capacity to learn, memorize and create relationships among data. They are ideal for modeling non-linear, dynamic, noise-ridden and complex systems. A survey on existing literature shows limited usage of the ANN method to predict total, diffuse and direct solar radiation. Much of the work on the prediction of solar radiation has been done using the empirical method. Estimation of total solar radiation using ANN has been done for locations in North and South America, Europe, Asia, Middle East and some parts of northern and southern Africa. Solar radiation predictions using ANN in eastern and central Africa are non-existent. Therefore the study utilized the ANN method to predict total solar irradiation and its two components. The data from the four measurement sites in Uganda were split into two such that the dataset from three stations, that is, Mbarara, Lira and Tororo, was used for training Neural Networks and formulating empirical models. The dataset from the Kampala station was reserved for validating both the ANN and empirical models. A typical neural network is made up of input, hidden and output layers. The present study utilized meteorological parameters as inputs and solar radiation as output from the neural network. A feedforward back-propagation neural network was used in this study with six input variables for the prediction of total solar irradiation, which included: sunshine hours, cloud cover and maximum temperature, together with latitude, longitude and altitude. The diffuse component had as input the following variables: latitude, longitude, altitude, total solar irradiation, sunshine hours, average temperature, relative humidity and cloud cover; whereas the direct component had: latitude, longitude, altitude, total solar irradiation, sunshine hours and maximum temperature. There was a challenge in determining which transfer function and training algorithm to use in training the neural networks, and also determining the number of hidden layers and number of neurons in the ANN structure. Total, diffuse and direct solar irradiation values were estimated for eight other stations in Uganda where measurements of solar radiation were not made. This was done using the appropriate ANN models. Consequently, a pool of measured and estimated values of solar irradiation was created and used for the interpolation task. Moving Average interpolation method was used for interpolating total solar irradiation and its two components. The ANN architecture designed was a feedforward back-propagation with one hidden layer and tangent sigmoid, as the transfer function. The output layer utilized a linear transfer function and Levenverg-Marquardt as the training algorithm. The number of neurons in the hidden layer was fifteen for total solar irradiation, eighteen for diffuse solar irradiation and six for direct solar irradiation. The ultimate part of the design process of the ANN model was the variation of the inputs to the network and evaluation of the corresponding ANN model in pursuit of the most appropriate prediction model. The evaluation involved correlation and error analysis using mean bias error (MBE) and root mean square error (RMSE). The appropriate ANN model for prediction of total solar irradiation was one which had the following input variables: latitude, longitude, altitude, sunshine hours, maximum temperature and cloud cover. The model yields predictions with MBE=0.069MJm-2 and RMSE=0.504MJm-2. The appropriate ANN model for prediction of diffuse solar irradiation was one which had the following input variables: latitude, longitude, altitude, total solar irradiation, sunshine hours, average temperature, cloud cover and relative humidity. The model yields predictions with MBE=0.018MJm-2 and RMSE=0.268MJm-2. The appropriate ANN model for prediction of direct solar irradiation was one which had the following input variables: latitude, longitude, altitude, total solar irradiation, sunshine hours and maximum temperature. The model yields predictions with MBE=0.005MJm-2 and RMSE=0.197MJm-2. A pool of measured and estimated values of total solar radiation and its two main components have been interpolated, successfully. The results are three sets of solar radiation maps for Uganda, with normalized percentage root mean square errors of 2.5%, 3.0% and 1.8% for the interpolation of total, diffuse and direct solar irradiation, respectively.
Assessing the impact of biological control in the Rivers Kagera, Mara, Pangani and Sigi.

(Makerere University, 2007-07) Katagira, F.

Water hyacinth Eichhornia crassipes (Martius) Solms-Laubach, is considered to be the worst aquatic weed worldwide. Biological control using Neochetina weevils was initiated in Tanzania in1995; however this control mechanism was successful in Lake Victoria where water hyacinth was reduced by 80%, but failed in some water bodies (Rajabu et al., 2000; LVEMP, 2001). Studies were conducted during 2003 to 2005 to assess the impact of biological control in the rivers Kagera, Mara, Pangani and Sigi and to evaluate potential effect of nitrogen, phosphorus and silt on weevil establishment in greenhouse conditions at Kyaka near Kagera river in Kagera region, Tanzania. The objectives were achieved by studying the following aspects: (i) The status of water hyacinth and Neochetina weevils in fresh water rivers (Kagera, Mara, Pangani and Sigi rivers) of Tanzania; (ii) Effect of nitrogen and phosphorus on weevil establishment and damage on water hyacinth; (iii) Effect of silt on establishment and performance of Neochetina weevils on water hyacinth; and (iv) Effect of water quality on weevil establishment and damage on water hyacinth. The study on rivers involved sampling of water hyacinth and determination of population densities and growth. Weevil densities, stages of development and feeding scars were also determined. Results showed that Kagera river had the highest water hyacinth densities (44.2 plants m-2) followed by Mara (32.8 plants m-2), Pangani (27.2 plants m-2 ) and least in Sigi (22.8 plants m-2). Plant height was highest in Mara (51.04 cm), followed by Kagera, Pangani and the least height in Sigi (28.6 cm). Other plant parameters namely, leaf length and width and root length followed the same trend. Kagera river had the highest number of ramets per plant (1.13) followed by Mara, Sigi and Pangani (0.69). The number of adult weevils per plant was highest in Sigi (1.93) and Pangani (1.78) and lowest in Kagera and Mara (0). The number of weevil feeding scars per plant was highest in Pangani (22.1) and Sigi (17.81). Overall Mara (1.4) and Kagera (0.21) had the lowest. Water hyacinth growth suppression and population reduction was only evident in Pangani and Sigi rivers and was associated with abundance and feeding by weevils. On the other hand, the weed continued to proliferate in Kagera and Mara rivers in Lake Victoria basin despite monthly weevil releases. The effect of N and P on water hyacinth growth and Neochetina weevil establishment and efficacy was conducted under greenhouse conditions. It consisted of 0 (control), 50 mg N L-l , 100 mg N L-l, 42.5 mg P L-l and 85 mg P L-l and their combinations. Weevil damage was suppressed at higher N (100 mg N L-l) but not high P application rates. Plants fed with high levels of N had low counts of adult weevils and pupae. On the other hand, growth of water hyacinth was limited in low N by 40%, yet weevil numbers, eggs, larvae and pupae per plant as well as weevil damage, increased at low N. Similarly, the number of adult weevil feeding scars per plant was higher (P<0.01) in lower N than at high levels. However, P concentration had no significant effect on number of weevil feeding scars per plant. Total plant N and P varied among nutrient application rates and N uptake depended on P availability; and plant N content increased with increase in P application rate. There was a significant positive correlation (P<0.001) between number of eggs and larvae per plant. The number and length of roots per plant increased with P application while application of N resulted to significant reduction in number and length of roots per plant. Water quality in the Kagera, Mara, Pangani and Sigi rivers differed. The highest total nitrogen was found in Kagera (0.99 mg N L-l) while the lowest was in Sigi (0.12 mg N L-l). Similary, total phosphorus was highest in Kagera (0.36 mg P L-l), while the lowest was in Sigi (0.12 mg P L-l). Likewise, electrical conductivity was highest in Kagera (969.8 µscm-l) follwed by Mara while Pangani and Sigi had the lowest indicating pollution loads in Kagera and Mara rivers. Water temperature was high in Pangani (30.39 oC) and Sigi (29.4 oC), while Mara had (26.2 oC) and Kagera had the lowest (26.23 oC). Air temperatures and relative humidity followed the same trend. It was concluded that high N and P levels might be partly responsible for poor weevil damage on water hyacinth in eutrophic habitat such as in Kagera and Mara rivers. On addition, the low temperatures and relative humidity may have contributed by limiting the weevil activities. The study on the effect of silt on the water hyacinth and weevil development and efficacy consisted of control (no silt applied) and silt at levels 17 kg, 51 kg and 85 kg in 50 litres of water applied in order to achieve distances of 20, 10 and 0 cm between the root tips and silt topmost level/surface. Silt and water for the experiments was from Lake Victoria and Kagera river. There was reduced weevil reproduction in treatments with silt as evidenced by low numbers of eggs, larvae, pupae and adult weevils. In contrast water hyacinth plant populations, leaf length and number of ramets were significantly enhanced (P<0.05) by silt application. Water hyacinth grown in water and silt from Kagera river, had higher weevil feeding scars per plant were 32.2 at low silt (17 kg) and 8.7 at 85 kg silt level indicating reduced weevil damage at high silt. A significant and positive relationship (r = 0.881, P < 0.01) was obtained between water hyacinth leaf length and lamina width. Silt levels appear to directly affect different life stages of the weevil, thereby reducing the ability of the insects to multiply to populations that can suppress growth of water hyacinth. Sediment loads in Kagera and Mara rivers may have contributed to poor establishment of Neochetina weevils and favoured water hyacinth proliferation.
The molecular biology of sulfadoxine-pyrimethamine drug resistance of plasmodium falciparum strains in Uganda

(Makerere University, 2007-08) Sendagire, Hakim

In November of 2000, Uganda changed its anti-malarial policy to replace chloroquine (CQ) with a combination of CQ and sulphadoxine–pyrimethamine (SP) as the first line agents. The idea of the combination was to delay the development of malaria resistance to either drug when used alone. Information was limited on the efficacy of either drug yet SP resistance was increasing in East Africa. SP resistance has been associated with point mutations in Dihydrofolate reductase (DHFR) and Dihydopteroate Synthase (DHPS) in vitro, but correlations with in vivo outcomes are less clear. Four separate studies were done over a four-year period, to monitor and evaluate the rate of development of resistance using both clinical and molecular methods. In 1999 in Kampala, Uganda, adults and children with uncomplicated falciparum malaria were treated with SP (1.25 mg/kg pyrimethamine, 25 mg/kg sulfadoxine) and assessed using WHO clinical and parasitological criteria. Analysis of DHFR/DHPS mutations was done using PCR and restriction endonuclease digestion methods. Clinical treatment failure was 11% at 14 days, increasing to 30% at 28 days, after excluding new infections. Mutations in DHFR 108-Asn (94%) and 51-Ile (91%) were very common. All infections with less than two DHFR/DHPS mutations were successfully treated. The prevalence of DHFR 59-Arg (57%), DHPS 437-Gly (58%) and 540-Glu (66%) was lower, with many samples showing a mixed wild-type and mutant profile. DHFR 59-Arg, DHPS 437-Gly and 540-Glu showed clinical significance mostly at day 28 {DHFR 59 (0.061 by day 14 and 0.003 by day 28), DHPS 437 (0.072 and 0.015) and 540 (0.031 and 0.0007) on days 14 and 28 respectively for each codon}. Combining them, 59-Arg + 540-Glu had the strongest association with clinical outcome at 28 days (p=0.002). To examine the theory that increasing resistance is associated with increasing number of mutations, there was a 50% risk of treatment failure in patients with 5 mutations than 0-4 mutations (p=0.0001). The second study was designed to provide baseline information on the efficacy of SP and the prevalence of molecular markers that are associated with SP resistance in Kasangati. Blood samples were collected on Whatman’s filter paper from 169 consenting patients who were diagnosed with malaria. Patients were treated with SP and followed for 14 days. SP monotherapy was efficacious for 140 of 163 (85.9%) treated patients. We found a high level of mutations in alleles that have previously been reported to be associated with SP resistance, but there was no statisticall significant relationship between clinical outcomes and molecular markers (P. value 0.106). With the exception of codon S108 in DHFR (DHFR S108N was at 94.9%), frequencies of DHPS mutant and mixed alleles combined (A437G 89% and K540E 83.9%) were higher than those of DHFR (N51I 58.4%, C59R 31.3%). The last two studies were done to evaluate the national anti-malarial policy drugs and assist evidence based national policy guidelines. We compared the clinical, parasitological and molecular findings of one study with treatment arms of CQSP, amodiaquine (AQ) plus SP (AQSP) done in 2003 with a study done 1 year earlier (2002) using SP alone There was a notable decrease in adequate clinical response (ACR) by day 14 from 92.7% with SP to 80% with the combination CQSP, a year later. AQSP combination was found to have the best effect (ACR 94.3% compared to CQSP 80%, p. value 0.008). There were no early treatment failures in the AQSP group. Treatment failures were recorded at 20% on day 14 and 43% on day 28 for CQSP treatment and 5.7% by day 14 and 28.8% by day 28 in the AQSP group. The number of mutations that are associated with SP resistance increased from 2002 to 2003 at all loci monitored, from 83.8 to 100% at codon 108, 58.7 to 76% at codon 59 in the DHFR gene, and from 58.8 to 86% at codon 437 and 33 to 43% at codon 540 in the DHPS gene. We conclude that there has been a rapid development of resistance since the introduction of new policy guidelines. AQSP was found to be a superior drug combination compared to CQSP and could be used as a low cost alternative to co-artem at the moment.
Phytochemical and bio-activity evaluation of Commicarpus plumbagineus standl: A medicinal plant used traditionally in reproductive health care in Uganda

(Makerere University, 2007-09) Ojok, Miriam Fiona

Commicarpus plumbagineus Standl. (Nyctaginaceae) is a traditional medicinal plant used to treat a variety of diseases including urinary tract infections, prevention of miscarriages, purification and improvement of blood texture, fibroids, dysmenorrhoea, hypermenorrhoea and coagulation of blood. However, no scientific validation on the claimed cure of diseases by C. plumbagineus had been carried out and as such; the chemical profile and bioactivity were not known. This research was carried out to upgrade herbal medicine through scientific validation and evidence-based research on bioactivity. The leaf and stem of C. plumbagineus were collected, dried and extracted in diethyl ether, ethanol and water. The tests carried out included; uterine motility, phytochemical screening, antimicrobial (disc diffusion method) and whole blood and ELISA assays for immunology. Phytochemical results revealed that saponins, glycosides, sugars, oleanolic acid, blue terpenoids, steroids, phytosterols, carboxylic acid and nitrogen containing compounds were abundant as in other species found in Nyctaginaceae. Antimicrobial tests showed that the plant was inactive at 50% (0.05g/ml) on both Candida albicans and Staphylococcus aureus therefore did not show antimicrobial activity. Immunology tests revealed that the stem and leaf aqueous extracts induced higher IFN-gamma (responsible for antibody production) as compared to IL-10 (associated with successful pregnancies) even after stimulation with PHA (mimics an infection). The plant is therefore an immune booster. Uterine motility results showed that the leaf aqueous extract caused uterine relaxation at 10% (0.01g/ml) through to 80% (0.08g/ml) and the stem extract caused uterine relaxation at 80% (0.08g/ml). The relaxing effect on the uterine muscle by C. plumbagineus supports the prevention of miscarriages, dysmenorrhoea and hypermenorrhoea. There is need for more research in the areas of dosage, toxicity, invitro tests and broad spectrum antimicrobial activity.
Characterization of anthocyanins from selected plant species in Uganda

(Makerere University, 2008-10) Byamukama, Robert

Different plant species were collected from different parts of the country in the period 2003 to 2007. Extraction of the plant material collected was done using methanol acidified with various amounts of trifluoroacetic acid depending on the anthocyanins present in each particular plant species. Purification of the crude methanol extracts was done by partition (several times) against solvents, ethyl acetate and petroleum spirit of boiling range 40-600C. Further purification and separation was performed using ion exchange resins (amberliteXAD-7 and sephadex LH-20) and toyopearl LW- 40, packed in chromatographic columns. Final separations of the anthocyanins were achieved by preparative High Performance Liquid Chromatography. The anthocyanins were identified by a combination of Thin Layer, High Performance Liquid Chromatography (HPLC), online UV spectroscopy, one Dimensional and two Dimensional (1H &13C) Nuclear Magnetic Resonance spectroscopy (NMR) techniques and Liquid Chromatography-Mass spectrometry (LC-MS). The quantitative determination of anthocyanins was accomplished with Analytical HPLC using reference samples isolated under the same conditions. The colors of the Hippeastrum cultivars were described by the CIELab coordinates L* (lightness), C* (chroma) and hab (hue angles). Twelve plant species, which included; Rubus pinnatus, Rubus rigidus, Carissa edulis, seven Hippeastrum cultivars, Acalypha hispida and Ricinus communis, were analysed. Ten structures of anthocyanins including four novel ones were characterised in this study and five papers (Paper I –V) (attached in Part II) have been published.
Restoration potential of species in the degraded forested sites in Kibale National Park, Uganda.

(Makerere University, 2009-02) Omeja, Aria Patrick

Introduction: Kibale National Park (KNP), like most protected areas in Uganda has had many challenges over the years. In 1971, illegal destruction and encroachment occurred in the game corridor which linked Kibale National Park with Queen Elizabeth National Park, but ended in 1992. Kibale National Park, currently managed by the Uganda Wildlife Authority (UWA), was under the Forest Department before to 1993. One of the management objectives of Forest Department then was sustained production of wood and timber. To achieve this, plantations of exotic tree species were established in 1950 –60s (Osmaston 1959). When UWA took over management of these areas, the management objective changed, and plantations of exotic tree species were clear-felled and the areas left to regenerate naturally. In the southern boundary of the park at Mainaro where elephant grass and Lantana camara had suppressed tree regeneration, intensive reforestation has been undertaken. Since areas of the park are now recovering from historic human impact, there is a need to examine the effectiveness of different management schemes to restore the forest cover. This is a subject that has not been much studied in Kibale or elsewhere, but is required to guide natural forest planning and management, hence, the need for this study. Objectives: The general objective of the study was to evaluate the restoration of woody tree biomass and tree species richness that occur through different land use and management options in Kibale National Park (KNP) and the specific objectives were: (i) To develop a general above ground allometric equation that can be used to calculate overall above ground biomass of standing trees in the disturbed areas of Kibale National Park; (ii) To determine the amount of biomass accumulation and species richness in an abandoned former pine plantation; (iii) To determine the significance of enrichment planting using indigenous tree species after pine plantation establishment and removal; (iv) To evaluate how successful the restoration efforts conducted in Kibale have been, and in comparison to other areas around the tropics; and (v) To find out the most cost efficient approach to promote restoration in the degraded sites in KNP. Methods: Most published allometric relations are typically site-specific, reflecting the original objective for which they were developed (Girgal & Kernik 1984; Pastor et al. 1984) and are not developed for regenerating forest. Since, this study was conducted in an area that was a young regenerating forest, an allometric regression equation of biomass accumulation of woody trees species for this specific area was developed by selecting a sample of early successional trees of varying sizes for harvest and determining their dry weight. This follows methods that rely on the combination of regression equations to produce either species-specific allometry or allometry for groups of species (Jenkins et al. 2003; Keith et al. 1999; Lwanga 2003). Trees in forest lands that were adjacent to the park were identified, and their stem diameter were measured at 0.3 m and 1.3 m above the ground hereafter referred to as diameter at ground height (DGH) and diameter at breast height (DBH) respectively. The trees were then cut and their total lengths measured. Individual trees that were of similar size to those regenerating in the study area (i.e., DBH 1.1 – 10.0 cm and DGH 1.6 – 11.0 cm; within the weights of 0.25 – 10 kg; n = 200) were selected. The choice of tree species for biomass estimation was made based on survey of the vegetation of common tree species in the study area. In total, 200 stems (20 stems per species) were harvested. The species included Albizia grandibracteata Taub., Bridelia micrantha Baill., Celtis africana Burm. f., Celtis durandii Engl., Clausena spp, Maesa lanceolata Forssk., Funtumia latifolia Stapt, Milletia dura Dunn., and Trema orientalis Blume. First, the branches were removed and the total weight of stems and leaves determined. Second, the tree stems were cut into smaller sections and air dried in the laboratory until constant mass was attained. Once all components had reached a constant dry weight, the total weight of the tree was estimated. Findings: The most pressing issue in many regions including Kibale has been the need to assemble information on detailed above ground biomass allometric relationship for the woody tree species on degraded areas. This study has made the first move towards providing such information for this region. The results from this work do not only enhance our understanding of the effects of anthropogenic activities on the forest ecosystem, but also provide much needed information that will facilitate planning, development, and management of forest resources in the degraded areas. It is worth noting that, over the last two decades, there has been a great deal of clearing of forested areas driven by the need for more agricultural land, fuel wood, and building materials for the rapidly expanding human population in the region (Chapman & Chapman, 2003). In 1997, National Environment Management Authority estimated that wood fuel provided 99.2% of energy used for cooking in Kabarole district of Uganda that hosts over 50% of the 795 km2 of KNP. However, comparison of results of the present study and those from Lwanga (2003) and Naughton & Chapman (2002) indicated a significant change in tree species composition and woody tree biomass of KNP, a change that is attributed to a large extent to the recovery of the tree species after disturbance. Other studies within KNP have discovered a number of pits for storing grain and an array of potshards in an area that have traditionally been considered undisturbed forest (Lang Brown and Harrop 1962). It therefore seems likely that in tropical forests, such as Kibale, human activities have altered forest composition for a considerable period of time. Differences in tree biomass and forest composition between areas may reflect the period of time that the area has had to recover from human induced disturbance. However, based on what is known about the life history of the canopy trees in Kibale, distinguishing an area that had been disturbed 1,000 years ago from one that had been disturbed 400 years ago would be a very difficult task. Conclusion: (i) The following allometric equation can be used to estimates the above ground as an indication of forest restoration: y=2.053x + 2.056: (R2 = 0.653, n =200); (ii) Restoration efforts conducted in Kibale and elsewhere around the globe all appear to be successful, based on a long term-time frame. This highlights the resilience of tropical forest systems to recover from disturbance; (iii) Given the three restoration projects evaluated within Kibale, fire protection for 12 years resulted in the biomass accumulation of 2,858 kg/ha/year. The effect of pine establishment and their harvest resulted in the rate of biomass accumulation of between 1,735-2,720 kg/ha/year. The enrichment planting resulted in biomass accumulation of 1,306 kg/ha/year, and fire control after 32 years resulted in the accumulation of 933 kg/ha/year. These amounts of biomass accumulated indicate that the forest is being restored and will play a significant role in atmospheric carbon absorption; (iv) Enrichment planting after pine plantation establishment and removal does not contribute significantly to biomass accumulation, counter to earlier reports presented to UWA. This suggests that UWA should more strongly request that the long-term researchers of Kibale provide data or impressions about future management plans; (v) Given the level of biomass accumulation in the different treatments considered, it can be said that fire protection is the most cost efficient approach to promote restoration in this region and it provides suitable incentives for the involvement of local communities. Recommendations: (i) Both the prevention of fires and the enrichment planting, such as that conducted at Mainaro, appear to provide positive social benefits for the local communities. However, in the future, the research community (anthropologists or sociologists) working in conjunction with UWA and international conservation biologists should evaluate if the benefits to the local communities (e.g., employment) result in more positive impressions of the park by the local community and if this potential positive impression translates into reduced illegal practices conducted by the local community; (ii) Given the extensive cover of Lantana camara, in the restoration compartments in the south of Kibale and its potential to negatively influence restoration in the future, an assessment on the value that L. camara removal would have on tree regeneration should be a priority for future research.
The effects of fire on the regeneration of acacia species in Lake Mburo National Park, Uganda

(Makerere University, 2009-06) Badaza-Nakileza, Rose Susan

The thesis investigated the effect of fire on the regeneration of Acacia species in Lake Mburo National Park, Uganda. The mechanism that cause the effects and the manner in which the effects are influenced by fire are also discussed. The study was carried out in Lake Mburo National Park between 1997 and 1998. To explain the relationship between the incidence of herbivory and the height and position of the sprouts, the effects of fire and cutting were investigated. All sprounts were monitored for incidence of herbivory. Results of fire experiments in five sites in Lake Mburo National Park showed that the quantity and quality of fuels available for fire varied widely in relation to weather but also in relation to the degree of use by man and herbivores. The amount of phytomass available was an important factor in determining the fire intensity, scorch height and char height. Furthermore, the intensity of fire also depended on the season and frequency of burning. Wet periods which foster shrub establishment also promoted abundant grass growth. However, frequent burning prevented the building up of fuel load sufficient to support a high intensity fire. Although fire induced the germination of all Acacia species in the study, the ability of seeds to germinate depended on the fire intensity and the seed size. Low fire intensities induced the germination of Acacia hockii seeds. However, these positive effects of fire on seed germination were short lived and only 20% of the seedlings got established. The population structure of Acacia species was investigated and non- uniform population structure was found. The results indicated that population structures differed widely among stands and changes in population structures after fire varied from site to site depending on the fire intensity and Acacia species. Although Acacia hockii was found to be dominant, most individuals were trapped in the lower height size classes. While fire intensity was the prime factor influencing the effects of fire on Acacia species, increase populations of species can also be attributed to frequent burning and increased human activities in and around Lake Mburo National Park. The results of this study indicated that frequent burning and the subsequent low intensity fires experienced in Lake Mburo National Park favoured the proliferation of Acacia hockii. The factors that enhanced the ability of Acacia species to escape being forced back by fire were also investigated. In all instances, the escape height varied among species with Acacia hockii escaping at the lowest height and Acacia polyacantha had the heighest escape height. In this study, the capacity for Acacia species to escape fire depended on the fire intensity, bark thickness, height and diameter of individual plants at the time of burning. Sprouts from Acacia sieberriana and Acacia gerrardii were most preferred by the browsers. Although the incidence of herbivory decreased with increase in height of the sprouts, the position of the sprouts did not determine palatability of all Acacia species. Only sprouts from the base of Acacia sieberriana were browsed whereas for Acacia gerrardii all sprouts were browsed irrespective of the position. The study also showed that cutting down of Acacia species for charcoal burning and building poles was a major factor in determining the tree structure and the sprouts density. All individuals of the different species in the study area sprouted after cutting irrespective of the size class and the position of the sprouts was correlated to the size of the original tree. Small individuals sprouted at the base and as the size increased, the position of the sprouts changed. Burning of the stumps after cutting had more negative effects on Acacia gerrardii compared to other Acacia species where only individuals in 4.00- 4.99m height size class retained the capacity to sprout. Fire was also seen to increase the flowering capacity of the Acacia species. Acacia hockii had the shortest individuals flowering whereas Acacia polyacantha started flowering after attaining a height of 4m. There was a positive correlation (r = 0.974, n = 4, P < 0.05) between the minimum height of flowering and the maximum height an individual could attain. Sprouts from burning and or cutting treatments were also monitored for flowering and only sprouts of Acacia hockii were able to flower the next flowering season after treatment and produced more seeds.
Characterization of selected pesticide residues in sediments of the Ugandan side of Lake Victoria

(Makerere University, 2009-06) Wasswa, John

This study investigated the role of biogeochemical processes in influencing bio-availability and biodegradation of selected pesticides in Lake Victoria. Due to the hydrophobicity nature of most pesticides, sediments which serve as sink to the less water soluble chemicals were selected as a matrix of study. To achieve the set objective, an inventory of the pesticides use in the Ugandan side of Lake Victoria catchments was made, seasonal variability of pesticide concentrations in sediments were determined, followed by sorption and pesticide degradation studies within the lake sediments. Information on the pesticides used was gathered using questionnaires and professional interviews. Surface sediment samples were collected using a corer, extracted for pesticide residues using solid dispersion methods and extracts cleaned up using gel permeation chromatograph – GPC. Analysis for pesticide residues in extracts was done using a temperature programmed Gas Chromatograph equipped with a Nitrogen Phosphorous Detector and an Electron Capture Detector. External and inter-laboratory confirmatory tests were done using a dual column and dual detector approach coupled with a sulphuric acid treatment method of selected extracts. Validation of selected samples was done using a Gas Chromatograph equipped with a Mass Selective Detector. Sorption experiments were conducted in mixed solvents (methanol-water) systems and sorption coefficients in aqueous systems were obtained using the theory of the Solvophobic model. Degradation experiments to determine the kinetics of pesticide transformation by different microbial communities were defined in terms of the extractable concentrations based on method extraction efficiency. The presence of microbial communities within the lake sediment was established using a DNA screening technique. Results from the survey indicate the major challenges associated with pesticide use in Uganda as being use of un-registered pesticides, inappropriate packaging, storage, disposal and human exposure due to poor handling of the pesticides and their containers. A total of eighteen pesticide residue/metabolites have been identified and quantified within Lake Victoria sediments with chlorpyrifos recording the highest mean value of 4.18 μg/kg (dry weight) and endosulfan sulfate being the most frequently detected (42%) pesticide residue. The study has also detected residues of pesticides which are not registered for use in Uganda. Sorption studies have indicated that sorption on containers can cause grave errors in the estimation of sorption coefficients, especially for those chemicals with very low water solubility. Chlorpyrifos has been found to have a higher affinity to the lake sediment than both the β- endosulfan and α- endosulfan in that order. Degradation studies indicate that α-endosulfan, β-endosulfan and chlorpyrifos degrade faster in unsterilized than in sterilized sediment samples of Lake Victoria, suggesting that microorganisms contribute to the degradation processes of the three pesticides within the lake sediment. A DNA screening for the presence of bacteria that degrade pesticides within Lake Victoria has indicated presence of microbes in the lake environment that are capable of degrading phenyl derived pesticides, toluene derived pesticides and xylene derived pesticides. The fate of pesticide residues within Lake Victoria has been described using the "Quantitative Water Air Sediment Interaction" (QWASI) model. With this model, it has been predicted that the residence times (years) of chlorpyrifos, α –endosulfan, β- endosulfan, endosulfan sulfate, pp- DDT, HCHgamma, and chlordane within the lake system are; 3.3 , 6.3, 6.1, 3.2, 0.4, 14.0 and 1.7, respectively.
The feeding ecology, ontogeny and larval feeding in Labeo Victorianus Boulenger 1901 (Pisces: Cyprinidae)

(Makerere University, 2009-06) Owori, Wadunde Akisoferi

Labeo victorianus was one of the most popular commercial fish of Lake Victoria highly cherished by all communities within the lake basin. The fish was over fished and by the early 1960s it had virtually disappeared from the catches of the lake. There has been growing interest by both biodiversity conservators and fish consumers to restore the population of Labeo victorianus. It was identified in the Lake Victoria Environmental Management Project (LVEMP) as one of the species for restoration. Several investigations were carried out in the current study to provide the scientific knowledge that will facilitate the domestication of Labeo victorianus as a way of restoring its declined population. Ripe L. victorianus broodstocks were collected from the spawning grounds and induced under culture conditions using fresh extracts of the pituitary gland of the mirror carp (Cyprinus carpio) following a method used by Hecht et al. (1997) for catfish. The ontogenetic developmental of its digestive system were noted to provide the knowledge required for designing its diets and larval feeding program. This information would facilitate commercial production for Labeo victorianus seed fro aquaculture. An experimental investigation of the most suitable larval diets for L. victorianus was also carried out. Several diet types ranging from zooplankton, phytoplankton and dry diet were tested as starter diets for L. victorianus larvae. Suitability of the diets was compared on the basis of survival and growth. In another part of the study, the structure of the digestive system of Labeo victorianus was studied with the aim of determining the functional adaptability to the feeding ecology. By comparing the results with adaptations of similar structures of fish species of known feeding ecology, inference was made on the feeding ecology of Labeo victorianus. Results of this work were expected to provide clues on the feeding habits of this fish. The last investigation analyzed the composition of the gut content of Labeo victorianus to provide a better understanding of the diets and feeding habits of this fish. The analyses were carried out on gut contents collected throughout an annual cycle to see if there was seasonality in the feeding habits. The gut contents were isolated by food type and organisms identified. They were quantified using both the point and the frequency of occurrence methods to determine their importance in the diets. Labeo victorianus larvae hatch out with undeveloped digestive system and unable to start feeding. They rely on the yolk sac for at least 3 days before they area able to start feeding, although the yolk sac lasts up to 5 days. Therefore, feeding of the larvae can not start until 3 days post hatch. By Time 2 (T2), the mass of larvae was significantly higher in fish fed on either cladocerans or a combination of cladocerans and dry feed (Scheffe post-hoc tests, P < 0.05) (Fig. 2.9). Fish fed cladocerans exhibited the second highest mass, but it was not significantly greater (p > 0.5) than the dry feed or rotifer treatments. Survival was lower (P < 0.5) for L. victorianus larvae supplied with micro-algae than those supplied with either zooplankton alone or a combination of zooplankton and microalgae soon after the onset of exogenous feeding (at day 20). The fish fed on zooplankton exhibited a significantly higher mass than fish fed on micro-algae and the combination (Scheffe post hoc tests, P < 0.05). By this time survivorship in the dry feed treatment (70±6.0% of the original number) was lower than in the other three food treatments (posthoc tests, P < 0.05), but there was no difference in survivorship among the cladoceran, rotifer, and cladoceran/dry feed combination (88.7±9.0%, 86±9.2% and 91±7.8% of their original numbers, respectively) (post-hoc tests, P > 0.05). It was concluded that cladocerans and a combination of dry diet were the most suitable starter diets for L. victorianus larvae. The R. Sio and R. Kagera populations of L. victorianus did not differ significantly (p > 0.001) in all the morphotypes investigated, meaning that these two populations are very similar in their feeding adaptation. However, in the morphotypes that determine the normal position in the water column, L. victorianus was less (P < 0.5) adapted for benthic habitat than (C. gariepinus and B. docmak) but not as pelagic (p < 0.5) as the Nile tilapia. It was therefore concluded that L. victorianus was adapted for substrate habitats in relatively shallow waters. In its feeding ecology, all samples of L. victorianus collected at night (1900 hrs) and dawn (0500hrs) had empty guts. This indicates that this fish does not feed at night. This fish feeds on a diverse range of diet types ranging from detritus, plant parts, zooplankton, diatoms, and insect parts. By both the point and the frequency of occurrence methods the most dominant five items that were found in the guts of the R. Sio population were detritus, fine sand particles, cladocerans, Baciliophyta (diatoms), and Cyanophyta, in that order, and they contributed 84.6% of the gut content. The most dominant five items found in the guts of the R. Kagera population were detritus, fine sand, plant tissue, Chlorophyta, and Baciliophyta, in that order, and they contributed 90.5% of the gut content. In both of these cases there was no evidence of the nutritional value of sand, and it was concluded that it was probably ingested by accident during feeding on rocks. The most dominant diet types, that could be categorized as epiphytes, tend to grow on surfaces of objects (substrates). This finding suggests that L. victorianus could be grown on periphyton, such as the ‘acadja’ system. The implications of the findings of the current study for commercial aquaculture are discussed.
Role of Acacia and Erythrina trees in forest regeneration by vertebrate seed dispersers in grasslands of Kibale National Park, Uganda

(Makerere University, 2009-09) Kiwanuka, Majid

The central question of this study was ‘Do fire-resistant savanna trees such as Acacia sieberiana and Erythrina abyssinica and frugivorous vertebrates influence forest regeneration in the fire-prone grasslands of Kibale National Park, Uganda?’ In order to address the above question, seed rain and species richness and abundance of seedlings/saplings of forest trees were estimated both below and ten meters away from the crowns of these savanna trees for a period of six months (August 2007- March 2008). In addition, the rate of seed removal by seed predators in both areas below and ten meters away from crowns was estimated. Both areas, below and ten meters away from crowns, received seed rain and contained seedlings/saplings similar to those of the trees in the nearby forest. Species richness and abundance were significantly higher below than ten meters away from the crowns. However this was not the case with regards to seed rain. Although distance from the forest edge had a negative influence on species richness and abundance of seedlings/saplings, crown sizes of savanna trees had a positive influence. It was also found that there was no significant correlation between seed rain and distance from the forest edge. Furthermore the rate of seed removal by seed predators below and ten meters away from the crowns of savanna trees was not significantly different. The results from this study therefore demonstrate that forest regeneration is possible below the crowns of Acacia sieberiana and Erythrina abyssinica trees in the grasslands of Kibale National park. Key words: frugivorous vertebrates, seed rain, savanna trees, seed dispersal, seed predation, forest regeneration.
The prevalence of Crustacean parasities on Nile Perch (Lates niloticus) and Nile Tilapia (Oreochromis niloticus) in Lake Kyoga, Uganda.

(Makerere University, 2009-09) Mutaaye, Stephen

A study to investigate the prevalence and distribution of crustacean ectoparasites on the commercial fish species, Nile perch and Nile tilapia in Lake Kyoga, Uganda, was conducted through a survey for six months starting from February 2007 and ending July 2007. Crustacean ectoparasites are common parasites of fresh water fish and are known to cause detrimental effects to their hosts. Therefore the study particularly sought to provide information on the identity and intensity of the crustacean parasites infesting major commercial fish from Lake Kyoga of which little has been done and documented. Data was collected from inshore and offshore of each of the following sampling stations: Iyingo, Bukungu and Lwampanga once a month. A total of one thousand two hundred and seventy (1270) fish were sampled and examined for copepod ectoparasite. Six hundred and twenty nine (629) fish were Nile tilapia and six hundred forty one (641) were Nile perch. The findings showed that Oreochromis niloticus from Lake Kyoga was highly infested by crustacean ectoparasites of genus Lernaea and insignificantly infested with Dolops spp. However, Nile perch was found free of those parasites. The Lernaea parasites mostly occurred on the skin surface and rarely found on the inner lining of the operculum, gills and fins. Generally, incidence and intensity of infestation increased with size of the host. Size class of 30 - 34.9 cm (TL) was found to be the most infested followed by size class 25 - 29.9 cm (TL). Immature fish (juveniles) were free from any ectoparasite. There was no significant difference in the levels of infestation between the fish samples taken from inshore and offshore waters, different sampling stations or in different sexes. The study concluded that there was high parasite infestation of fish in Lake Kyoga where Oreochromis niloticus was mostly infested with crustacean ectoparasite, Lernaea sp. The level of infestation was comparable in both sexes of fish. The study recommends that the level of infestation by Lernaea and Dolops on fish in Kyoga be monitored and environmental friendly measures be adopted to control incidence of the parasites in the lake. It also recommends that the effects of these crustaceans on fish and on public health be investigated.
Biogeographical examination of the butterfly fauna in selected West Albertine Rift Forests

(Makerere University, 2009-09) Kasangaki, P.

This study was conducted with the main aim of evaluating the factors that may influence butterfly species richness and distribution (i.e. forest size, altitude, forest disturbance, average rainfall, temperature and distance from the supposed Pleistocene refugium) in 17 West Albertine rift forests (WARF’s), Uganda. Butterflies which were collected by the Forest Department (now National Forests Authority, NFA) and preserved at the Makerere University Museum were used for this study. Relevant biodiversity reports prepared by the Forest Department were reviewed to gather information on the physical and environmental attributes of the forests. A list of 630 butterfly species was complied for the 17 forests. Cluster, Principal component, Canonical correspondence and regression analyses were done to relate and compare butterfly species richness among the forests in order to establish the relationship between the butterfly species richness and the environmental and physical variables. These analyses helped in identifying the most important variables influencing the butterfly species richness and distribution in the forests. Forests with similar physical and environmental conditions had similar species richness. The environmental and physical variables which seemed to influence the species richness and distribution in the forests were forest size, number of plant species, altitude and levels of forests disturbance. Plant species richness appeared to be the most significant factor accounting for 49% of the butterfly species richness in the forests. Distance from the supposed Pleistocene refugium also seemed to have been responsible for species richness in the forests although not significantly. However, more research/survey should be done to involve population analysis (number of individuals other than only the number of species should be recorded) to ascertain the effect of forest disturbance on the butterfly species richness and population densities.
Post-harvest handling practices and physico-chemical characteristics of shea (Vitellaria paradoxa) fruit in Uganda

(Makerere University, 2009-11) Omujal, Francis

This study assessed the post harvest handling practices and physico chemical characteristics of shea butter in the parkland areas of Uganda. To investigate post harvest practices of shea butter (Vitellaria paradoxa) fruit, a total of 275 respondents were interviewed between July 2007 and January 2008. The collected socio-economic data were coded, entered in SPSS computer programme and analysed. In the same period, fresh shea fruit pulps were collected, dried and analyzed for proximate and mineral compositions. The shea butter oil extracted from the shea kernels of the shea fruit were also analysed for variability in physico chemical characteristics and fatty acid profile extracted by n-hexane solvent, traditional boiling and mechanical cold pressing methods. The proximate analysis showed that the shea fruit pulp, crude oil, crude fibre, crude protein, total carbohydrate, vitamin C and caloric value contents ranged between 1.5-3.5%, 10-15%; 3.1-4.2%, 61-64%, 85.59-124.86mg/100g and 248-256 Kcal/100g, respectively. The mineral composition of the shea fruit pulp consisted of calcium 35.18-95.58 mg/100g, potassium 42.04-63.55 mg/100g, magnesium 18.14-24.21mg/100g, sodium 7.07-18.12 mg/100gm and iron 3.41-3.76 mg/100g. The shea seed kernel butter/oil content ranged between 41-54% and the physico chemical characteristics such as colour, refractive index, viscosity, acid value, peroxide value, saponification value, iodine value and α- tocopherols ranged between orange to orange–yellow, 1.670-1.690, 2.4-2.8cP, 2.3-12.59mgKOH/kg, 2.10-2.50meq/kg, 160- 192mgKOH/g, 39.21-41.37 I2g/100g and 26.3-44.4mg/100g, respectively. The shea butter fatty acid profile: palmitic , stearic, oleic, linoleic and arachidic acid fatty acids ranged between 6.52-8.12%, 28.65-30.94%, 55.54-57.63%, 6.18-7.79% and 0.65-0.90%, respectively. The physico-chemical characteristics of shea butter extracted by n-hexane solvent extraction, traditional boiling and cold pressing methods for the colours, refractive index, viscosity, acid value, peroxide value, saponification value, iodine value and α tocopherols ranged between yellow-orange to yellow-red; 1.468-1.469, 2.4-2.8cP, 2.3-6.9mgKOH/kg, 2.2-5.09mEq/kg, 145-192mgKOH/kg, 36-38 I2/100, 34.4-45.5mg/100g while the fatty acid profile: palmitic , stearic, oleic, linoleic and arachinic acid fatty acids ranged between 6-8%, 29-31%, 55-57%%, 6-8%and0.65-0.98%, respectively. While the proximate and mineral composition of the shea fruit pulp makes shea fruits a potential nutritious fruit in the parklands, the physico-chemical characteristics and fatty acid profile of shea butter on the other hand make it a suitable raw material for food, cosmetic and pharmaceutical products. The quality of shea butter oil is also comparable to other edible oils such as soya bean oil (Glycine max). The indigenous post harvest handling practices of shea butter in Uganda is appropriate, however, there is a need to investigate further their influence on quality of shea butter..
Iodisation of Lake Katwe salt, Kasese District

(Makerere University, 2009-11) Loum, Janani

The raw rock salt was analysed for chemical composition, refined and then iodised. The selected species determined are those known to hinder iodine retention in edible salt, namely; sulphates 20.7 % w/w, carbonates 31.7 % w/w, zinc 18 ± 4 ppm magnesium 945 ± 3 ppm, iron 168 ± 2 ppm and calcium 74 ± 3 ppm as ionic species were determined. The total amount of chloride was 1.54 % w/w. Purification was by fractional crystallization, precipitation, and adsorption techniques. This yielded 85 % w/w salt as sodium chloride. The impurities were reduced markedly with sulphate 3.83 % w/w, carbonate 1.42 % w/w, zinc 4.22 ± 0.15 ppm, magnesium 7.64 ± 2 ppm, iron 7.40 ± 0.25 ppm and calcium 4.40 ± 0.3 ppm. Iodisation of the salt was done by addition of potassium iodate ( 0.378 g ) to the refined salt ( 200 g ) to give 100 ppm of iodine. Iodine retention was determined by iodometric titration conducted on the salt sample for two weeks. The quantity of iodine retained in the salt varied between 82.3 ± 3.8 ppm and 99.8 ± 9.0 ppm.. The salt can be profitably exploited if attention is focused to the manufacture of other products alongside salt e.g. fertilizers, carbonates, bicarbonate, stearate, and sulphate salts. This will subsidise on operation costs and reduce on the cost of the salt produced.
Habitat utilization and reproductive biology of Nile Tilapia (Oreochromis Niloticus) in Albert Nile, Nebbi District

(Makerere University, 2009-12) Nyakuni, Liverious

Some aspects of habitat utilization (distribution, abundance, size classes, condition factor) and reproductive biology (sex ratio, size at first maturity, fecundity) of O. niloticus were examined in Albert Nile in Nebbi District between January and July 2007 with an aim to understand the extent of habitat utilization and reproductive potential of the species among habitat types of Albert Nile. A total of 596 fish samples were collected from four major habitat types namely Vossia cuspidata, Eichhornia crassipes, Phragmites mauritianus dominated shores and open water areas using experimental gill nets of mesh size range 37.5mm to 125mm and small seine net operated from a boat or beach. The study established that the inshore areas of Albert Nile were characterized by diverse habitat types ranging from open water areas to various vegetation types (V. cuspidata, E. crassipes, and P. mauritianus) that provided suitable habitats for fish. The habitats were further characterized by shallow, slow flowing, warm water of average temperature 28.4ºC, and high dissolved oxygen with mean concentration of 6.4 mg/l, and pH oscillating around neutral value (7.04) which makes it suitable environment for fish habitation. Oreochromis niloticus was found in all habitat types but the relative abundance varied among habitats with highest number recorded in V. cuspidata (35.1%) followed by open water (27.5%) and the least in P. mauritianus habitat (14.9%). The mean length of O. niloticus captured in all the habitat types in Albert Nile was 16.4 cm TL. High abundance of juveniles of sizes ≤ 20 cm TL were found in V. cuspidata and E. crassipes habitats while mature individuals were more abundant in the open waters, indicating the importance of macrophytes as critical habitats for fish breeding, nursery grounds and providing shelter for protection against enemies. The condition factor (K) for O. niloticus in all the habitat types varied from 1.56 to 2.48 and the differences among habitats were significant (F= 6.4312, p < 0.05) with highest mean value among fish from open water (K= 2.19) and least in V. cuspidata (K= 1.92) which indicates that the habitats occupied by O. niloticus were not the same in terms of food availability, seasonality and other environmental factors that support fish life. Sex ratios were different among habitat types but in V. cuspidata and E. crassipes the differences from the hypothetical 1:1 were significant (χ2 = 4.36, p < 0.05 & χ2 = 3.18, p < 0.05 respectively). The overall sex ratio (male: female) of the pooled population of O. niloticus in this part of Albert Nile was 1:1.29 which was not significantly different from the hypothetical 1:1 (χ2 = 7.42, p < 0.05) but generally females were more abundant than males in the study area which is a good indication of high potential for replacement of stocks and sustainability of the fisheries resources in the river. The mean length at first maturity was 22.4 cm and 23.0 cm TL in females and males respectively while the number of eggs produced per female ranged from 412 to 2380 and the overall mean fecundity was 854 eggs per fish. The relationships of fecundity with body length and body weight were found to be linear and increasing with increasing fish length and body weight. Fecundity correlated more closely with body length (r = 0.88, p < 0.01) than body weight (r = 0.73, p < 0.01) but in both cases the relationship was significant (p < 0.01).
Discovery and verification of osteopontin and Beta-2-microglobulin as promising markers for staging Human African Trypanosomiasis

(The American Society for Biochemistry and Molecular Biology, 2010) Matovu, Enock ; Enyaru, John ; Tiberti, Natalia,

Human African trypanosomiasis, or sleeping sickness, is a parasitic disease endemic in sub-Saharan Africa, transmitted to humans through the bite of a tsetse fly. The first or hemolymphatic stage of the disease is associated with presence of parasites in the bloodstream, lymphatic system, and body tissues. If patients are left untreated, parasites cross the blood-brain barrier and invade the cerebrospinal fluid and the brain parenchyma, giving rise to the second or meningoencephalitic stage. Stage determination is a crucial step in guiding the choice of treatment, as drugs used for S2 are potentially dangerous. Current staging methods, based on counting white blood cells and demonstrating trypanosomes in cerebrospinal fluid, lack specificity and/or sensitivity. In the present study, we used several proteomic strategies to discover new markers with potential for staging human African trypanosomiasis. Cerebrospinal fluid (CSF) samples were collected from patients infected with Trypanosoma brucei gambiense in the Democratic Republic of Congo. The stage was determined following the guidelines of the national control program. The proteome of the samples was analyzed by two-dimensional gel electrophoresis (n= 9), and by sixplex tandem mass tag (TMT) isobaric labeling (n= 6) quantitative mass spectrometry. Overall, 73 proteins were overexpressed in patients presenting the second stage of the disease. Two of these, osteopontin and β-2-microglobulin, were confirmed to be potential markers for staging human African trypanosomiasis (HAT) by Western blot and ELISA. The two proteins significantly discriminated between S1 and S2 patients with high sensitivity (68% and 78%, respectively) for 100% specificity, and a combination of both improved the sensitivity to 91%. The levels of osteopontin and β-2-microglobulin in CSF of S2 patients (µg/ml range), as well as the fold increased concentration in S2 compared with S1 (3.8 and 5.5 respectively) make the two markers good candidates for the development of a test for staging HAT patients.
Gasification of biochar from empty fruit bunch in a fluidized bed reactor

(MDPI AG, 2010) Nsamba, Hussein Kisiki ; Salleh, M. A. Mohd ; Yusuf, H. M. ; Ghani, W. A. Wan Ab Karim

A biochar produced from empty fruit bunches (EFB) was gasified in a fluidized bed using air to determine gas yield, overall carbon conversion, gas quality, and composition as a function of temperature. The experiment was conducted in the temperature range of 500–850 °C. It was observed that biochar has the potential to replace coal as a gasification agent in power plants. Hydrogen gas from biochar was also optimized during the experiment. High temperatures favor H2 and CO formation. There was an increase of H2 over the temperature range from 500–850 °C from 5.53% to 27.97% (v/v), with a heating value of 30 kJ/g. The C conversion in the same temperature range increased from 76% to 84%. Therefore, there are great prospects for the use of biochar from EFB as an alternative fuel in power plants, as a renewable energy providing an alternative path to biofuels. Results from this work enable us to better understand syn gas production under high treatment temperatures.

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