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2004

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Short-Term Scheduling Of A Hydro-Thermal System Using Linear Programming Technique, A Kyaruzi Dec 2004

Short-Term Scheduling Of A Hydro-Thermal System Using Linear Programming Technique, A Kyaruzi

Tanzania Journal of Engineering and Technology (TJET)

The paper discusses the short term scheduling of Hydrothermal for Tanzania Electricity Supply Company (TANESCO) Power System. The problem is to determine on hourly interval the Hydro and Thermal generation. The scheduling keeps balance between production and consumption in a reliable and economical way during the study period. Linear programming (LP) mathematical model using MATL4B has been developed. The constraints are hydrological balance, thermal power plants limitations and load requirements. The result from LP solution gave low operation cost. Generation was mainly from hydro and all reservoirs elevation was high at the end ofplanning period.

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Hydrographic Aspect Of Chole Bay, Mafia Island, Alfonse Dubi Dec 2004

Hydrographic Aspect Of Chole Bay, Mafia Island, Alfonse Dubi

Tanzania Journal of Engineering and Technology (TJET)

Mafia has been a port on the monsoon trade routes from the Arabia to Sofala for almost 2000 years. The Island has not changed significantly since ancient times and retains a traditional culture of fishing and subsistence agriculture. By 1991, development of tourism on the Island seemed very slow. Factors limiting the number of visitors include lack of adequate travel connections between the island and the mainland, and inadequate and poor hotel services. Currently, accessibility to Mafia Island has improved. Mafia Island can now be reached by air in addition to the traditional sea travel. However, the Island does not …

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Participatory Evaluation And Improvement Of Cassava Processing Machines For The Eastern Zone Of Tanzania, V Silayo Dec 2004

Participatory Evaluation And Improvement Of Cassava Processing Machines For The Eastern Zone Of Tanzania, V Silayo

Tanzania Journal of Engineering and Technology (TJET)

Cassava processing machines previously introduced in Tanzania were chippers and graters of the International Institute Of Tropical Agriculture (IITA) design. Popularization of such machmes in Tanzania required thorough participatory testing with stakeholders. When tested with farmers in Muheza and Kibaha districts average throughputs were 11-18 kg/h, 752 kg/h and 270 kg/hfor the manual chipper, engine-powered chipper and the engine-powered grater, respectively. Despite their low throughputs the manual chipper and the grater were Veo difficult to operate, and therefore demanded improvement. Improvement on these machines included modifications on the design for increased throughput, ease of operation and safety. The improved machines …

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Aeration Efficiency Of A Three-Phase Fluidized Bed Bioreactor During Food Industry Wastewater Treatment, S Manyele Dec 2004

Aeration Efficiency Of A Three-Phase Fluidized Bed Bioreactor During Food Industry Wastewater Treatment, S Manyele

Tanzania Journal of Engineering and Technology (TJET)

The implementation Of a three-phase fluidized bed bioreaclor (TPFBB) in food- processing wastewater (FPW'W) treatment is reported. This study includes the modification Of the air distributor (plate design and gas-liquid mixing) for the bioreactor and resting of its aeration efficiency under different liquids. The aeration efficiency for wastewater samples collected from a soft drink processing industry and tannin processing industry (TANWA T) and tap water were compared. The aeration efficiency parameters studied include bed expansion, air holdup. volumetric oxygen mass transfer coefficient, and alpha factors. The variation of these parameters With air flow rates were studied at different liquid heights, …

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Usefulness Of Technology Life Cycle In Tanzania: The Case Of The Ipl Developed Technologies, Abdallah Chungu Dec 2004

Usefulness Of Technology Life Cycle In Tanzania: The Case Of The Ipl Developed Technologies, Abdallah Chungu

Tanzania Journal of Engineering and Technology (TJET)

This study sought to identify the adoption rate of technologv innovations developed by the Institute Of Production Innovation (IPI) at the University Of Dar-es-Salaam since 1984 to 1997 using a sigmoid shaped curve (S-shaped curves) to predict the life cycles of the respective technologies. Depending on the stimuli imparted to the specific technology, some of such technologies for instance, cinva ram and block making machines with hollow/spacer/louver exhibited longer life period as indicated by a series Of infer-connected S-curves. Other technologies including but nor limited to sunflower oil processing kit-winnowers, scorcher with one stove, seed roller, standard wheelbarrow, and manual …

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Energy Meter Reading And Tampering Protection Through Powerline Communication Channel, S Naiman Dec 2004

Energy Meter Reading And Tampering Protection Through Powerline Communication Channel, S Naiman

Tanzania Journal of Engineering and Technology (TJET)

POwer utility companies have suffered revenue losses due to uncollected bills and energy tampering for many years. The use of powerline communication to overcome the problems has been proposed. This needs tampering detection and transceivers capable of communicating data through poww•line channel. This paper identifies different methods Of tampering, presents simulated results for tampering detection scheme and proposes a Direct Sequence Spread Spectrum (DSSS) wilh Binary Phase Shift Keying (BPSK) transceiver design for energy metering as a solution to the problem. The choice of DSSS-BPSK modulation scheme is based on its robustness and its ability to spread signal inro wide …

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Comparative Study Of The Dynamics Of Circulating Fluidized Bed Riser And Downer Of Equal Diameters, Samwel V. Manyele Dec 2004

Comparative Study Of The Dynamics Of Circulating Fluidized Bed Riser And Downer Of Equal Diameters, Samwel V. Manyele

Tanzania Journal of Engineering and Technology (TJET)

The microscopic flow dynamics of the 100-mm internal diameter riser/downer circulating fluidized bed (CFB) unit were monitored using a solids concentration fiber optic probe. The comparison was conducted by comparing radial profiles Of the dynamic parameters derived from time-series analysis techniques (statistical and chaos analyses). The solids concentration signals used were recorded under similar operating conditions (gas velocity of 8.0 m/s and solids flux of 100 kg/m2s). Similar axial elevations were compared (entrance and fully developed sections of die reactors). A1 each loca!ion, the signals were sampled a! afrequency of 970 Hz for duration of 30 seconds. It was observed …

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Information And Communication Technology Applications In The Tanzanian Health Sector, M Victor Dec 2004

Information And Communication Technology Applications In The Tanzanian Health Sector, M Victor

Tanzania Journal of Engineering and Technology (TJET)

The potential role of Information and Communication Technology (ICT) in the health sector is to improve the delivery of health services and would also help to deal with major constraints in uplifting the health standards Of Tanzanians. ICT in heath can be used to facilitate remote consultation, diagnosis and treatment. The objective Of the study was exploratory in nature and aimed at determining the awareness level of the länzanian health sector on various ICT applications which could be used in the sector. The study also aimed ar establishing the challenges to the implementation of ICT in the Tanzanian health sector. …

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Levels Of Nitrate And Phosphate In Some Satellite Lakes Within The Lake Victoria Basin, Tanzania, Jj Kulekana Dec 2004

Levels Of Nitrate And Phosphate In Some Satellite Lakes Within The Lake Victoria Basin, Tanzania, Jj Kulekana

Tanzania Journal of Science

Levels of nitrates (NO3-N) and phosphates (PO4-P) in some satellite lakes within the Lake Victoria basin were determined in Kagera (Lake Burigi), in Mara (River Mara) and in Mwanza region (Lake Malimbe) during August/September 2002 (dry season) and January/February 2003 (wet season). Water samples were collected using a van Dorn water sampler at chosen points from both deep and shallow areas of the water bodies. Results of the two surveys revealed that deep and shallow areas of the lakes had varying nutrient levels. In deep waters, PO4-P values ranged between 0.171-0.225mg/l, 0.067-0.364mg/l, and 0.043-0.096 mg/l in Lake Malimbe, Burigi and …

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Zooplankton Communities Of Selected Stations Of Lake Victoria, Rk Waya, Ja Mwambungu Dec 2004

Zooplankton Communities Of Selected Stations Of Lake Victoria, Rk Waya, Ja Mwambungu

Tanzania Journal of Science

Species composition and diversity of zooplankton communities of Lake Victoria (Tanzanian waters) were studied. In the shallow waters zooplankton were collected between March and April, and between August and December 2000. In deeper waters zooplankton were collected in August 2001. Overall, 20 genera and 29 species of zooplankton were observed in the shallow waters whereas 12 genera and 20 species of zooplankton were encountered in the deeper waters. The highest abundance was recorded in the deeper waters (2,481,633-2). In the shallow waters the cyclopoid copepods dominated the zooplankton community, the common species being Thermocyclops emini and Thermocyclops neglectus. In the …

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The Diversity Of Benthic Mollusks Of Lake Victoria And Lake Burigi, Ja Mwambungu Dec 2004

The Diversity Of Benthic Mollusks Of Lake Victoria And Lake Burigi, Ja Mwambungu

Tanzania Journal of Science

Molluscan diversity, abundance and distribution in sediments of Lake Victoria and its satellite lake, Lake Burigi, were investigated. The survey was carried out in January and February 2002 for Lake Victoria and in March and April 2002 for Lake Burigi. Ten genera were recorded from four zones of Lake Victoria while only three genera were recorded from Lake Burigi. In Lake Victoria the most diverse zone was Mara zone. The mollusca communities comprised of Bellamya, Gabbiella, Melanoides, Bulinus, Biomphalaria and Cleopatra (Gastropoda) and Corbicula, Eupera (Byssanodonta), Caelatura and Sphaerium (Bivalvia). Lake Burigi comprised of Melanoides, Bulinus and Biomphalaria. Melanoides tuberculata …

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Phytoplankton And Nutrients Studies In Magu Bay, Speke Gulf, Lake Victoria, (Tanzania) Following The 2001 Principal Rain Season, Jf Machiwa, C Lugomela, Ann Muzuka Dec 2004

Phytoplankton And Nutrients Studies In Magu Bay, Speke Gulf, Lake Victoria, (Tanzania) Following The 2001 Principal Rain Season, Jf Machiwa, C Lugomela, Ann Muzuka

Tanzania Journal of Science

Phytoplankton abundance and species composition in relation to some physico-chemical parameters were studied in Magu Bay, Lake Victoria, in May 2001. Investigations on the influence of Simiyu River on the biological and physical characteristics of the Bay were carried out. Surface and bottom currents flowed in the northeast direction close to the river mouth but were completely reversed after about 1.5 km from the river mouth. Most suspended particles brought in by the river were deposited within 0.5 km after entering the lake. Nutrient concentrations were generally high towards the eastern part of the bay as compared to the rest …

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Species Composition And Biomass Estimates Of Zooplankton In Some Water Bodies Within Lake Victoria Basin, Rk Waya, Ai Chande Dec 2004

Species Composition And Biomass Estimates Of Zooplankton In Some Water Bodies Within Lake Victoria Basin, Rk Waya, Ai Chande

Tanzania Journal of Science

Zooplankton communities were identified and their abundance and biomass estimated in some selected satellite lakes and Mara River in Lake Victoria basin, during wet and dry seasons in 2002. Samples were collected from eight water bodies. Three stations were sampled from each water body using a plankton net (40 µm mesh size) hauled vertically through the water column. The zooplankton community comprised mainly crustacea and rotifers. The results show that the number of species collected during the wet and dry seasons was 31 species and 28 species, respectively. The Shannon wiener diversity indices were not significantly different (Mann-Whitney U Test …

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Spatial Distribution Of Parasites Along The Gut Of The Catfish Clarias Gariepinus (Burchell, 1822) (Clariidae) From The Mwanza Gulf, Lake Victoria, G Nkwengulila, C Mwita Dec 2004

Spatial Distribution Of Parasites Along The Gut Of The Catfish Clarias Gariepinus (Burchell, 1822) (Clariidae) From The Mwanza Gulf, Lake Victoria, G Nkwengulila, C Mwita

Tanzania Journal of Science

The diversity, abundance and spatial distribution of parasites in the alimentary tract of Clarias gariepinus from the Mwanza Gulf were investigated. Ten parasite species were recovered; the Trematoda, Cestoda and Nematoda were each represented by three species while Dolops ranarum was the only crustacean recovered from the posterior part of the buccal cavity. Parasites diversity was highest in the small intestine and the stomach. Although the gut community of C. gariepinus studied was rich in intensity and individual numbers of helminth species, helminth infection in most sections of the gut comprised of monospecific infection and thus cohabiting interspecific interaction was …

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Phytoplankton Species Diversity And Abundance In Satellite Lakes Of Lake Victoria Basin (Tanzanian Side), Bc Sekadende, Ase Mbonde, S Shayo, Tj Lyimo Dec 2004

Phytoplankton Species Diversity And Abundance In Satellite Lakes Of Lake Victoria Basin (Tanzanian Side), Bc Sekadende, Ase Mbonde, S Shayo, Tj Lyimo

Tanzania Journal of Science

Studies on phytoplankton species diversity and abundance were carried out in 8 selected satellite lakes within the Lake Victoria basin during two wet seasons (March-April 2002 and January-February 2003) and one dry season (August-September 2002). Higher species richness (76 species) of phytoplankton species was recorded in rain season than in dry season (47 species). The observed species represents six classes, cyanophytes, chlorophytes, cryptophytes, basillariophytes, euglenophytes and dinophytes, of fresh water algal flora. Species diversity was generally low, with diversity indices (H\') ranging from 0.21 for Lake Kyarano to 0.09 for Lake Ikimba. On the contrary, Lake Katwe was richer in …

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Diurnal Feeding Patterns And Food Habits Of Lates Niloticus In The Speke Gulf, Lake Victoria, Ha Mhitu, Ai Chande Dec 2004

Diurnal Feeding Patterns And Food Habits Of Lates Niloticus In The Speke Gulf, Lake Victoria, Ha Mhitu, Ai Chande

Tanzania Journal of Science

Twenty four hour sampling sessions were conducted to investigate the feeding patterns and food habits of Lates niloticus in the Speke Gulf, Lake Victoria during January/February, July/August and December 2002. Feeding activity was more pronounced during daytime mostly in morning hours than during the night. The most dominant food item was haplochromines. There was a significant difference in the occurrence of food items in the gut of L. niloticus with time. However, there was no significant difference in the occurrence of food items in the habitat at different times. The study concludes with a recommendation for fishermen to set their …

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Relationship Between Water Transparency And Species Richness Of Surviving Haplochromines In Selected Habitats In Mwanza Gulf - Lake Victoria, Hdj Mrosso, Bs Msuku, O Seehausen Dec 2004

Relationship Between Water Transparency And Species Richness Of Surviving Haplochromines In Selected Habitats In Mwanza Gulf - Lake Victoria, Hdj Mrosso, Bs Msuku, O Seehausen

Tanzania Journal of Science

Several of the surviving haplochromine species have been recorded in habitats of different water transparencies within the Mwanza Gulf. Sampling for the haplochromines was carried out in muddy, rocky, sandy and vegetated habitats. All of the recorded species had been reported previously. Fewer species were encountered than previously reported in the same sampling stations. There was evidence for positive correlation between species richness and water transparency that was reinforced with data on ecological differentiation. Further exploration and conservation measures of diversity have been suggested for Lake Victoria haplochromines.

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Fish Species Composition, Size Structure And Distribution In Non-Trawlable Areas Of Lake Victoria (Tanzania) With Emphasis On Mwanza Gulf And Mori Bay, Jdr Bayona, B Msuku, S Mzighani Dec 2004

Fish Species Composition, Size Structure And Distribution In Non-Trawlable Areas Of Lake Victoria (Tanzania) With Emphasis On Mwanza Gulf And Mori Bay, Jdr Bayona, B Msuku, S Mzighani

Tanzania Journal of Science

Fish diversity studies in littoral non-trawlable areas of Lake Victoria (Tanzania) were undertaken during six systematic surveys (November 2000 to December 2002). Information on fish species composition, size structure as well as spatial and temporal distribution was generated from gill-netting, beach-seining and electric fishing. Lates niloticus, indicated a declining trend in composition from 78.9% in March 2001 to 5.1% in July 2002. The species, however, increased to 40.6 % in catch composition as of December 2002, exhibiting somewhat inverse trends in distribution with Oreochromis niloticus and haplochromines in the lake fisheries. The surveys identified over 50 species for which 42 …

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Diel Vertical Migration Of Zooplankton In The Tanzanian Waters Of Lake Victoria, Rk Waya Dec 2004

Diel Vertical Migration Of Zooplankton In The Tanzanian Waters Of Lake Victoria, Rk Waya

Tanzania Journal of Science

The diel vertical migration of zooplankton was studied in the Southern part of Lake Victoria in January and July 2002. A van dorn water sampler was used to collect zooplankton. In January 2002, zooplankton showed a pronounced diel vertical migration whereby zooplankton were moving upward at around sunset and swimming downward at sunrise. In July 2002 zooplankton showed diel vertical migration, but at around midnight Thermodiaptomus galeboides, Thermocyclops emini, Tropocyclops tenellus, cyclopoid copepodites, nauplius larvae and some rotifers showed downward movement. The diel vertical migration of zooplankton seems to be influenced by food, predation and light.

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Preparations Of Spherical Polymeric Particles From Tanzanian Cashew Nut Shell Liquid By Suspension Polymerization, L L Mkayula, Y M M Makame, T H Matechi Dec 2004

Preparations Of Spherical Polymeric Particles From Tanzanian Cashew Nut Shell Liquid By Suspension Polymerization, L L Mkayula, Y M M Makame, T H Matechi

Tanzania Journal of Science

Spherical Polymeric Particles (SPP) have been prepared from Tanzanian Cashew Nut Shell Liquid (CNSL) by suspension polymerization technique involving either step-growth or chain- growth polymerization mechanisms. The sizes of the SPP, which ranged from 0.1 to 2.0 mm were strongly influenced by the amounts of stabilizers in polymerization recipes used. The particles showed variable surface areas, indicative of the presence of pores in some of the preparations and the highest surface area recorded was about 260 m2g-1. The particles were found to exhibit Langmuir-type adsorption isotherms with saturation capacity of about 9.0 and 44.2 mg/g for Na+ and Ca2+, respectively. …

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Total Mercury Concentration In Common Fish Species Of Lake Victoria, Tanzania, J F Machiwa Dec 2004

Total Mercury Concentration In Common Fish Species Of Lake Victoria, Tanzania, J F Machiwa

Tanzania Journal of Science

Total mercury (THg) concentration was analysed in muscles of common fish species of Lake Victoria in the eastern and southern parts of the lake using cold vapour Atomic Absorption Spectrophotometric technique. Mercury concentration in all fish species was generally lower than the WHO maximum allowable concentration (500 ng/g ww) in edible fish parts. The maximum concentration of THg in Lates niloticus samples was 396 ng/g ww. Samples of Oreochromis niloticus had THg concentration ranging between <0.01 and 419 ng/g ww. Clarias gariepinus had THg concentration ranging between 1.2 and 239.1 ng/g ww. All less common fish species, such as, Labeo victirianus, Synodontis victoriae, Oreochromis leucostictus, Schilbe intermedius, Brycinus jacksonii, B. sadleri, Tilapia rendalii, Tilapia zilii and Haplochromines had THg concentration below the WHO maximum allowable limit (500 ng/g ww). The study showed that Hg from small-scale gold mining activities in Lake Victoria basin is not transported to the lake by fluvial discharge. Other possible pathways of Hg input to Lake Victoria are discussed.

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Contamination Of Water And Sediments By Obsolete Pesticides At Vikuge Farm, Kibaha Distric, Tanzania, M J Mihale, M A Kishimba Dec 2004

Contamination Of Water And Sediments By Obsolete Pesticides At Vikuge Farm, Kibaha Distric, Tanzania, M J Mihale, M A Kishimba

Tanzania Journal of Science

Sediments and water from Vikuge State Farm, Coast Region, Tanzania, where, in 1986, a “donation” of 170 m3 of partially expired pesticides were stored in an open shed- which eventually collapsed, were analysed for 80 different pesticide residues and metabolites. DDT and HCH, two of the most persistent organochlorines pesticides, were the most dominant pesticides found in both matrices. In sediments the levels were up to 99,620 mg/kg dry weight of ΣDDT and up to 7,400 mg/kg dry weight of ΣHCH. The mean total HCH concentrations were 0.95 μg/l in tap water, 0.28 mg/l in surface water and 3.09 μg/l …

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Studies On The Fisheries And Biology Of Oreochromis Urolepsis (Pisces: Cichilidae) In The Mtera Resorvoir (Tanzania), F M M Chale Dec 2004

Studies On The Fisheries And Biology Of Oreochromis Urolepsis (Pisces: Cichilidae) In The Mtera Resorvoir (Tanzania), F M M Chale

Tanzania Journal of Science

The fisheries and some aspects of the biology of Oreochromis urolepis of the Mtera Reservoir (Tanzania) were examined in August 2002. It was observed that there was no proper management of the reservoir's fisheries. Beach seine fishing dominated the fishery. Nearly all the O. urolepis caught by this type of gear were juveniles. The number of fish caught by the beach seines was very high, some times up to 4,000 fish per haul. The beach seines also destroy the spawning sites for the tilapias. Mean total lengths of O. urolepis caught in gillnets of legal mesh sizes (ranging from 88 …

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Performance Analysis Of Cdma-Based Wireless Communication Systems Using The Simplified Improved Gaussian Approximation Method, H N Kundaeli Dec 2004

Performance Analysis Of Cdma-Based Wireless Communication Systems Using The Simplified Improved Gaussian Approximation Method, H N Kundaeli

Tanzania Journal of Science

The limitations initially prevalent in CDMA-based systems have been gradually solved thereby making CDMA a very promising access mode for future communication systems. Following the move towards higher data transmission rates, however, a number of other problems have emerged that need to be tackled. As a result, current world-wide research on CDMA-based systems is geared towards high speed, highly mobile multimedia communication applications. In this paper, the performance of a multi-user DS-CDMA communication system operating in a Rayleigh fading environment is investigated. Performance expressions are derived and the variation of the performance with various system parameters is presented.

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Changes In Population Structures Of The Major Species In Selected Satellite Lakes Around Lake Victoria Following Changes In Fishing Effort, E F B Katunzi, M A Kishe Dec 2004

Changes In Population Structures Of The Major Species In Selected Satellite Lakes Around Lake Victoria Following Changes In Fishing Effort, E F B Katunzi, M A Kishe

Tanzania Journal of Science

This paper evaluates the impacts of reduction in effort, increase in mesh sizes, and prohibition of illegal fishing gears in selected satellite lakes around Lake Victoria. The study was carried out in six satellite lakes by making investigations on fish collected from experimental and artisanal fisheries. The fishes were analysed for length frequencies, weight and numbers caught to determine the population structure of the fishes. Indiscriminate fishing by deploying illegal gears and increased fishing effort due to open access policy, the catch and diversity of the species in these lakes has declined. Establishment of Conservation Management Units (CMUs) as an …

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A Comparison Of Shell Size And Meat Weight Between Population Of The Bivalve Anadara Antiquata (Linnaeus 1758) From Four Sites Experiencing Different Levels Of Exploitation Pressure In Zanzibar, J P Shunula Dec 2004

A Comparison Of Shell Size And Meat Weight Between Population Of The Bivalve Anadara Antiquata (Linnaeus 1758) From Four Sites Experiencing Different Levels Of Exploitation Pressure In Zanzibar, J P Shunula

Tanzania Journal of Science

A comparative study on the shell size and meat weight between Anadara antiquata populations harvested from four intertidal mud flats subjected to varying exploitation pressure in Zanzibar was undertaken between August and December 2000. An analysis of the data from the four study locations Mazizni, Mbweni, Kisakasaka, and Jambiani showed that much smaller sized Anadara , with low meat weights were being harvested from Mazizini and Mbweni in comparison to those harvested from Kisakasaka and Jambiani. The first two sites were areas in which there was heavy exploitation of the animals in comparison to the last two. Mazizini and Mbweni …

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Elemental And Isotopic Compositions Of Organic Carbon And Nitrogen Of Recently Deposited Organic Matter In Empakai Crater And Its Implication For Climatic Changes In Northern Tanzania, A N N Muzuka Dec 2004

Elemental And Isotopic Compositions Of Organic Carbon And Nitrogen Of Recently Deposited Organic Matter In Empakai Crater And Its Implication For Climatic Changes In Northern Tanzania, A N N Muzuka

Tanzania Journal of Science

A 29 cm long core recovered from a water depth of 5 m in a small closed lake located in the Empakai crater northern Tanzania, is used to document the contents of organic carbon and nitrogen, stable isotopes composition of organic carbon and nitrogen, and C/N ratios and to infer climatic changes from these data. The δ 13C and δ15N values for this core, which averages - 16.5±2.1l and 11.0±5.6l respectively, show a general downcore decrease below 5 cm. However, within this general trend, two peaks enriched in 13C are observable at about 8 cm and 13 cm. The peak …

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Can Ports Contribute To The Economic Development Of The Regions They Serve? : An Examination Of The Potential, If Any, Of Using The Kenya Ports Authority As An Engine For Kenya's Economic Recovery And Development, Stanley Ndenge Chai Dec 2004

Can Ports Contribute To The Economic Development Of The Regions They Serve? : An Examination Of The Potential, If Any, Of Using The Kenya Ports Authority As An Engine For Kenya's Economic Recovery And Development, Stanley Ndenge Chai

World Maritime University Dissertations

No abstract provided.

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Parasites Of Clarias Gariepinus (Burchell, 1822) (Pisces: Clariidae) From The Mwanza Gulf, Lake Victoria, C Mwita, G Nkwengulila Dec 2004

Parasites Of Clarias Gariepinus (Burchell, 1822) (Pisces: Clariidae) From The Mwanza Gulf, Lake Victoria, C Mwita, G Nkwengulila

Tanzania Journal of Science

Seventeen species of parasites were recovered from 1071 Clarias gariepinus examined from the Mwanza Gulf of Lake Victoria. The parasite fauna comprised of four ectoparasites, a Monogenea, Hirudinea, crustacean and a Digenea; and fourteen endoparasites, five nematodes, five trematodes and three cestodes. Twelve parasite species were adults and five were larval forms. Ten were identified to species, six to genus and one to family level. Many species recorded are common to C. gariepinus, a few, e.g. Tylodelphys species is a first record in fish of Africa, thus represents a new host record. Spinitectus petterae is reported for the first time …

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Phytoplankton Species Diversity And Abundance In The Near Shore Waters Of Tanzanian Side Of Lake Victoria, Ase Mbonde, S Shayo, Bc Sekadende, Tj Lyimo Dec 2004

Phytoplankton Species Diversity And Abundance In The Near Shore Waters Of Tanzanian Side Of Lake Victoria, Ase Mbonde, S Shayo, Bc Sekadende, Tj Lyimo

Tanzania Journal of Science

The survey was carried out in January/February and July/August 2002 to investigate phytoplankton species diversity, spatial distribution, numerical abundance and total biomass (chlorophyll a concentration) in 10 selected stations on the Tanzanian side of Lake Victoria. At each station, samples for diversity data were collected by plankton net, which was towed at the surface water, while those for spatial distribution and abundance were collected using a 1 l Van Dorn water sampler. A total of 113 species belonging to 52 different genera were identified. Cyanobacteria were the most diverse group in both seasons. The concentration of chlorophyll a ranged from …

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