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Involvement Of Methyltransferases Enzymes During The Energy Metabolism Of The Anaerobic Archaeon Methanosarcina Semesiae Sp. Nov., Tj Lyimo
Tanzania Journal of Science
The methyl group transfer from dimethylsulfide (DMS), trimethylamine and methanol to 2-mercaptoethanesulfonic acid (coenzyme M) were investigated from cell extracts of Methanosarcina semesiae sp. nov. to evaluate whether the enzyme systems involved were constitutive or inductive. The extracts from cells grown on DMS exhibited methanogenic activity exclusively with DMS and methanethiol. Likewise when cells were pre-grown on trimethylamine or methanol the extracts only produced methane from the respective metaboilic substrate. Dimethylsulfide:methyl-coenzyme M transferase activity was dependent on ATP, but hydrogen did not stimulate activity. The fact that ATP could be replaced by the reductant Ti(III)-citrate indicates that reductive activation of …
Delineating The Jurassic To Mid Cretaceous Part Of The Pacific Apparent Polar Wander Path, Dcp Masalu
Delineating The Jurassic To Mid Cretaceous Part Of The Pacific Apparent Polar Wander Path, Dcp Masalu
Tanzania Journal of Science
The Jurassic to Mid-Cretaceous apparent polar wander path of the Pacific plate irrespective of ages have been delineated. Two poles have been established: one pole, which is relatively older than the other, is at 75.01°N/287.5°E (α = 6.9°) and the other pole is at 61.0°N°/304.7°E (!95 = 4.5°). These results indicate that the Pacific plate drifted southward during the Jurassic to Early-Cretaceous period. Additionally, the results demonstrate that there is an apparent consistent correspondence between changes of plate motion and significant shifts of the Jurassic to Mid-Cretaceous apparent polar wander path
Occurrence Of Digenean Larvae In Freshwater Snails In The Ruvu Basin, Tanzania, G. Nkwengulila, E. S. P. Kigadye
Occurrence Of Digenean Larvae In Freshwater Snails In The Ruvu Basin, Tanzania, G. Nkwengulila, E. S. P. Kigadye
Tanzania Journal of Science
A survey was carried out on digenean larvae infecting freshwater snails in five habitats in Dar es Salaam, Ruvu and Morogoro. 9424 snails belonging to 12 species from five families were examined for digenean infection from July 1996 – June 1997. 20 morphologically distinguishable cercariae were recovered. Multiple infections were not recorded. While the general prevalence of digeneans in snails was low (3.5%), variations occurred between seasons, among habitats and snail host species. Prevalence was high during the dry season but low in the rain season. Among habitats, highest prevalence was recorded at Kinondoni pond and lowest at Ruvu ponds, …
Abundance And Diversity Of Seagrass And Macrofauna In The Intertidal Areas With And Without Seaweed Farming Activities In The East Coast Of Zanzibar, Thomas J Lyimo, Esther F Mvungi, Yunus D Mgaya
Abundance And Diversity Of Seagrass And Macrofauna In The Intertidal Areas With And Without Seaweed Farming Activities In The East Coast Of Zanzibar, Thomas J Lyimo, Esther F Mvungi, Yunus D Mgaya
Tanzania Journal of Science
The diversity and abundance of seagrass and associated macrofauna were studied in transects with and without seaweed farms at Chwaka Bay and Jambiani, in the East Coast of Zanzibar. Eight seagrass species, namely Cymodocea rotundata, Cymodocea serrulata, Thalassia hemprichii, Thalassodendron ciliatum, Syringodium isoetifolium, Halodule uninervis, Halophila ovalis and Enhalus acoroides were recorded in the transects. The mean total biomass of seagrass at Chwaka Bay ranged from 142.4 ± 70.71 to 1652 ± 772.7 g dw/m2 and 212.9 ± 146.2 to 1829 ± 1692 g dw/m2 in station with and without seaweed farms, respectively. At Jambiani, the mean total biomass ranged …
Seed Longevity Of Dominant Plant Species From Degraded Savanna In Semi-Arid Tanzania, Hvm Lyaruu
Seed Longevity Of Dominant Plant Species From Degraded Savanna In Semi-Arid Tanzania, Hvm Lyaruu
Tanzania Journal of Science
Artificially buried seeds were followed by periodic exhumation and germination during 21 months in Kondoa Irangi Hills, central Tanzania. Viable seeds from thirteen selected species were buried in polythene envelopes at a depth of 15 cm below woodland vegetation. Lethal germination, fungal decay and insect infestation were singled out as the most important contributors to loss of viability among seeds. Hierarchical clustering based on a seed’s mean viability, seed shape and presence or absence of dispersal appendages, produced three distinct groups: (1) non-dormant seeds (2) seeds with enforced dormancy and (3) seeds with seed coat imposed dormancy. The low decay …
An Assessment Of Methods For Sampling Carabid Beetles (Coleptera: Carabidae) In A Montane Rain Forest, B. A. Nyundo, J. G. Yarro
An Assessment Of Methods For Sampling Carabid Beetles (Coleptera: Carabidae) In A Montane Rain Forest, B. A. Nyundo, J. G. Yarro
Tanzania Journal of Science
Pitfall trapping is the traditional method for sampling carabid beetles and other grounddwelling invertebrates. Tests were carried out in the Udzungwa Mountains National Park between March 1999 and July 2000. Results indicated that pitfall traps were less efficient compared to manual searching methods, both in terms of relative abundance and species richness of carabid beetles. The results are discussed in the context of biodiversity inventories in theEastern Arc Mountains.
Assessment Of Fecal Bacteria Contamination In Sewage And Non-Sewage Impacted Mangrove Ecosystems Along The Coast Of Dar Es Salaam, A. A. Abbu, Thomas J. Tj Lyimo
Assessment Of Fecal Bacteria Contamination In Sewage And Non-Sewage Impacted Mangrove Ecosystems Along The Coast Of Dar Es Salaam, A. A. Abbu, Thomas J. Tj Lyimo
Tanzania Journal of Science
Microbiological quality of the intertidal pool water was evaluated in sewage impacted (Mtoni Kijichi) and non-sewage impacted (Rasi Dege) mangrove forest sites along the coast of Dar es Salaam, Tanzania. The Most Probable Number method was used for estimating the total coliform (TC), fecal coliform (FC) and fecal enterococci (ENT) levels. In addition, physicochemical parameters (temperature, pH, salinity and nutrients) were measured. The results for microbial fecal indicators were compared to the World Health Organisation (WHO) and United States Environmental Protection Agency (USEPA) guidelines for marine recreational and shellfish harvesting waters. Fecal bacteria contamination was significantly higher at Mtoni Kijichi …
Characteristics And Dyes Biodegradation Potential Of Crude Lignolytic Enzymes From White-Rot Fungus Crepidotus Variabilis Isolated In Coastal Tanzania, G. Y. S. Gys Mtui
Characteristics And Dyes Biodegradation Potential Of Crude Lignolytic Enzymes From White-Rot Fungus Crepidotus Variabilis Isolated In Coastal Tanzania, G. Y. S. Gys Mtui
Tanzania Journal of Science
Lignocellulosic enzymes from Crepidotus variabilis collected from mangrove forests of coastal Tanzania were investigated by using standard methods, and their ability to degrade aromatic compounds were elucidated. The fungal crude enzyme filtrates had maximum laccase (Lac), lignin peroxidase (LiP) and manganese peroxidase (MnP) activities of 70 U/mL, 16 U/mL and 8, U/mL respectively. The crude enzyme extracts were able to oxidize rhemazol brilliant blue-R (RBB-R) dye, phenol, "-naphthol and pyrogallol. Also, they could remove up to 58% and 92% color from raw textile effluent and aromatic dyes, respectively, after 14 days of incubation at 30ºC and pH 4.5. Desalted and …
Chemical Constituents And Biological Activity Of Three Tanzanian Wild Mushroom Species, L.D. Baraza, C. C. Joseph, M. J. Moshi, M. H. H. Nkunya
Chemical Constituents And Biological Activity Of Three Tanzanian Wild Mushroom Species, L.D. Baraza, C. C. Joseph, M. J. Moshi, M. H. H. Nkunya
Tanzania Journal of Science
The three Tanzanian wild mushroom species Termitomyces letestui, Lactarius edulis and Agaricus sp. aff. arvensis yielded ergosterol, 5,8-peroxyergosterol and ergosta-5,22-dien-3β-ol, and a mixture of ergosterol, ergosta-7,22-dien-3β-ol and ergosta-7-en-3β-ol whose composition was deduced from gas chromatography/mass spectroscopic (GC/MS) analysis of the trimethysilylated mixture. GC/MS analysis of the lipid fraction from T. letestu revealed the presence of linoleic (C18:2), stearic (C18:0), oleic (C18:1), palmitic (C16:0), pentadecanoic (C15:0) and myristic (C14:0) acid. Polar T. letestui and L. edulis fractions yielded α,α,1'trehalose andmannitol. Some of the crude extracts from the three mushroom species showed mild antimicrobial, mosquito larvicidal and cytotoxic activities. The chemical composition …
Effect Of High Pressurized Carbon Dioxide On Escherichia Coli, I. P. Bateebe, O Kibazohi
Effect Of High Pressurized Carbon Dioxide On Escherichia Coli, I. P. Bateebe, O Kibazohi
Tanzania Journal of Science
Carbon dioxide at high pressure can retard microbial growth and sometimes kill microorganisms depending on values of applied pressure, temperature and exposure time. In this study the effect of high pressurised carbon dioxide (HPCD) on Escherichia coli was investigated. Culture of E. coli was subjected to high pressurised carbon dioxide at 15, 25 and 35 bar, and varying exposure times of 20, 40, 60 and 90 minutes at room temperature (27 oC). Microbial inactivation increased with pressure and exposure time. For the first 20 minutes reduction of viable microbial cells was 18%, 30% and 36% at 15, 25 and 35 …
Impact Of Small Scale Gold Mining On Soils Of The Wetland Forests In East Usambara, Tanzania, C. Kweyunga, R. B. M. Rbm Senzota
Impact Of Small Scale Gold Mining On Soils Of The Wetland Forests In East Usambara, Tanzania, C. Kweyunga, R. B. M. Rbm Senzota
Tanzania Journal of Science
Soil pits in disturbed and natural wetland forests of East Usambara were excavated and soil profile samples collected and analysed for physical and chemical properties. Their physical and chemical characteristics were found to be sharply different from those of the surrounding hills. Differences included lack of A Horizon, water saturation, presence of very high organic matter, very low pH and hence very poor in basic cations, and low microbial activity. Nutrient recycling, especially nitrogen and phosphorus, tended to shift from mineralization to immobilization. Effects of soil disturbance on both physical and chemical characteristics of the soils were also very vivid. …
Preparation And Nucleophilic Substitution Of The 2,4,6-Triphenylpyridinium Salts, Diazonium Intermediates And N,N-1,2-Benzenedisulfonylimides Of Chiral Amino Acids, S. A. Said
Tanzania Journal of Science
Three methods for preparation of D-amino acids by nucleophilic substitution on derivatives of their L-antipodes have been attempted. Nucleophilic substitution on optically active phenylalanine ethyl ester triphenylpyridinium salt yielded partial inverted azide products. The N,N-disulfonylimide intermediate of the same ester was synthesized in high yield and optical purity, but the substitution reaction on this compound was not achieved. Diazotization of amino acid ammonium chlorides and tosylates in solution of sodium azide in aprotic solvents gave optically active chloro and tosyl compounds instead of the intended azide products. Alternative methods to circumvent the problem of the competing ammonium salt counterions duringdiazotization …
Varietal Role In The Management Of The Larger Grain Borer, Prostephanus Truncatus (Horn) In Stored Maize, C. P. Rugumamu
Varietal Role In The Management Of The Larger Grain Borer, Prostephanus Truncatus (Horn) In Stored Maize, C. P. Rugumamu
Tanzania Journal of Science
The study determined the amount of haemolymph vitellogenin (Vg) of the Larger Grain Borer (LGB), Prostephanus truncatus (Horn) vitellogenic females reared on different maize varieties. The varieties were ZM 521, ZM 421, ECAVL1-DLN, WEEVIL A, LOCAL 1 and LOCAL 2. Sodium Dodecyl Sulphate-Polyacrylamide Gel Electrophoresis (SDS - PAGE) was conducted on the insect haemolymph. F1 LGB adults from each variety were used to determine Indices of Susceptibility (IS) of the varieties to the insect pest attack. Percentages of Vg from female insects and IS were in the order ZM 521>ZM 421> ECAVL1-DLN>WEEVIL A >LOCAL 1>LOCAL 2. Weight …
Evaluating The Performance Of Leucaena Accessions For Agroforestry In Sub-Humid Environment, Southern Tanzania, A. E. Majule
Evaluating The Performance Of Leucaena Accessions For Agroforestry In Sub-Humid Environment, Southern Tanzania, A. E. Majule
Tanzania Journal of Science
The performance of Leucaena accessions on acid soils in eastern coast Tanzania for agroforestry was evaluated for three years. Plant tree parameters assessed were fodder yield and plant stem height, stem girth, the number of total branches and poles production. Also, Leucaena psyllid, a common pest threatening the plants was also counted. Soil parameters assessed were pH organic carbon, total nitrogen, exchangeable calcium and magnesium. Result showed significant difference in growth between Leucaena accessions. Leucaena leucocephal cv K8 and Leucaena diversifolia were able to grow fast reaching 4.7 and 3.3 m respectively within a period of three years. Leucaena diversifolia …
Species Richness And Abundance Of Large Mammals In Zaraninge Forest, Coast Region, Tanzania, H. Y. D. Kiwia
Species Richness And Abundance Of Large Mammals In Zaraninge Forest, Coast Region, Tanzania, H. Y. D. Kiwia
Tanzania Journal of Science
A study on the large mammals of Zaraninge Forest was conducted using the line transect method between 1995 and 2001. They comprised 16 species from 7 families, including Bovidae (5), Canidae (1), Cercopithecidae (4), Felidae (1), Galagonidae (2), Orycteropodidae (1) and Suidae (2). Only nine species of primates and antelopes were encountered frequently enough for densities to be estimated. A total of 404 sightings from 40 counts were recorded, the majority being for blue monkey (34.9%) and Angolan colobus (26.0%). For galagos, 210 sightings from 58 counts were recorded, the majority being for Rondo galago (62.2%). Absolute density (individuals km-2) …
Species Richness And Abundance Estimates Of Small Mammals In Zaraninge Coastal Forest In Tanzania, H. Y. D. Kiwia
Species Richness And Abundance Estimates Of Small Mammals In Zaraninge Coastal Forest In Tanzania, H. Y. D. Kiwia
Tanzania Journal of Science
A study on small mammals (<2 kg) was conducted in Zaraninge Forest, Coast Region, Tanzania, in the dry and wet seasons from 1994 to1996. The forest was found to harbour 11 small mammal species from 11 genera and seven families. There was high similarity in the number of species caught during the two seasons (Sørensen Coefficient (CCs)=0.92), implying there to be minimal migration of the species in the area. A total of 159 individuals were caught during the dry season, rodents accounting for 89.3% of the total catch and insectivores 10.7%. The most common species were Cricetomys gambianus and Grammomys dolichurus that had trap successes of 2.83 and 1.11 respectively. During the wet season 185 animals were caught, rodents accounting for 92.4% of the total catch and insectivores 7.6%. Cricetomys gambianus was significantly more abundant during the dry season. Graphiurus murinus was not caught in this season and no trend in abundance was detected for the other species. Forest specialist species included Paraxerus palliatus and Petrodromus petersi. No species was endemic to the forest, near-endemic species that occur in coastal and Eastern Arc forests included P. petersi and Beamys hindei. B. hindei also occurs in a few other East African forests. Threatened species are B. hindei and P. palliatus that are vulnerable and P. petersi that is endangered. Lepus capensis is in Appendix I of CITES list and Hystrix cristata and Mellivora capensis in Appendix III. The forest, though small is in good health and fairly well protected, therefore the species are not in danger of being locally extinct in the near future.
Assessment Of The Status Of Lates Stappersii (Centropomidae) Stock In Lift-Net Fishery In Lake Tanganyika, Kigoma, Tanzania, I. A. Kimirei, Y. D. Mgaya
Assessment Of The Status Of Lates Stappersii (Centropomidae) Stock In Lift-Net Fishery In Lake Tanganyika, Kigoma, Tanzania, I. A. Kimirei, Y. D. Mgaya
Tanzania Journal of Science
An assessment of the status of Lates stappersii (Boulenger, 1914) stock in the lift-net fishery in Lake Tanganyika, Kigoma area, was carried out from January to December 2003. Results indicated that breeding is seasonal with peaks in February, July-August and December, and so was catch composition, with peaks in March, May and July–August that followed the abundance of its prey, Stolothrissa tanganicae. Catch per unit effort was similar between wet and dry seasons and peaked synchronously at all study sites probably as an indication of its abundance during those months; but also it could mean that the fishes were caught …
Masking Material As A Form Of Food Storage In Tiarinia Cornigera And Micippa Platipes (Brachyura, Majidae), J. Kyomo
Tanzania Journal of Science
Masking or decorating, which means attaching materials to the body, was investigated in two spider crabs Tiarinia cornigera and Micippa platipesin the subtropical waters of Okinawa, Japan. This life strategy was compared between sites over a period of time. All crabs of different ages and sizes attached materials, in one combination or the other, on their bodies proportionate to their carapace sizes. Older or larger crabs had their carapaces more completely covered with the materials than young or smaller crabs. Similar materials were found at all sites and had equal selective precedences by crabs. Red algae, particularly Gelidiella sp, was …
Genetics And Inheritance Of Seed Dormancy Inflicted By Seed- Coat Factors In Rice (Oryza Sativa L.), Z. L. Kanyeka
Genetics And Inheritance Of Seed Dormancy Inflicted By Seed- Coat Factors In Rice (Oryza Sativa L.), Z. L. Kanyeka
Tanzania Journal of Science
The study was undertaken to investigate the genetic mode of inheritance of dormancy imposed by the hull (seed coat) in rice seeds. Freshly harvested seeds of parents, F1 and F2 populations of a cross between a dormant cultivar Kisegese and non-dormant strain K2004 were used. Germination test of the de-hulled (without seed coat) and un-dehulled (whole or with seed coat) seeds were conducted at 10 days intervals starting at 15 days after harvesting (15DAH) for 65 days. The seeds were sown in petri dishes. Numbers of germinated and un-germinated seeds were recorded at 7 days after sowing. Germination of seeds …
Pathogenecity Of Two Strains Of Rice Yellow Mottle Virus On Aromatic Rice Cultivars, Z. L. Kanyeka
Pathogenecity Of Two Strains Of Rice Yellow Mottle Virus On Aromatic Rice Cultivars, Z. L. Kanyeka
Tanzania Journal of Science
Development of rice cultivars with resistance to rice yellow mottle virus (RYMV) requires characterization of pathogenecity of existing strains against susceptible cultivars. The pathogenecity of two RYMV strains; S4 and S“New” identified in Tanzania were assessed against seven local and introduced rice genotypes including cultivars Zambia, ITA173 and TXD 88. The two virus strains showed similar effects on the rice cultivar Zambia killing all the plants at 25d after inoculation. The strains significantly reduced the plant height, panicle length, and number of tillers per pot and total dry matter of all the two cultivars. In another trial, the pathogenecity of …
Diversity And Abundance Of Small Mammals In The Serengeti Kopjes, Tanzania, C. D. Timbuka, J. D. Kabigumila
Diversity And Abundance Of Small Mammals In The Serengeti Kopjes, Tanzania, C. D. Timbuka, J. D. Kabigumila
Tanzania Journal of Science
Diversity and abundance of small mammals in the Serengeti kopjes were studied between November 2000 and February 2002. From 22,500 trap-nights and 3,300 bucket-nights, 4,903 small mammals in 18 species, 14 genera, 6 families and 3 orders were recorded. Muridae was the most dominant family with nine species. The highest number of species was recorded in the Maasai (14), Mbuzi Mawe (13) and Seronera (12) kopjes. The least number of species recorded in the Simba, Barafu and Wogakuria kopjes, with eight species each. Species diversity was highest in the Maasai kopjes (H'=2.337) and lowest in the Wogakuria kopjes (H'=1.794), with …
Chemical Constitutents And Cytotoxicity Of Some Tanzanian Wild Mushrooms, V. Nyigo, L. D. Baraza, M. H. H. Nkunya, S. J. M. Mdachi, C. C. Joseph, A. Waziri
Chemical Constitutents And Cytotoxicity Of Some Tanzanian Wild Mushrooms, V. Nyigo, L. D. Baraza, M. H. H. Nkunya, S. J. M. Mdachi, C. C. Joseph, A. Waziri
Tanzania Journal of Science
The sterol ergosterol and ergosta-4,22-diene-3β,7α-diol, together with 4-hydroxybenzaldehyde were isolated from the mushroom species Polyporus molluscensis, Cantharellus isabelinus, C. symoensii and a Podaxis species. Their structures were established on the basis of spectroscopic data. The ethanol extracts of mushroom samples of Agaricus sp. and Termitomyces letestui also showed cytotoxicity against the brine shrimp larvae.
Influence Of Fructose On The Mechanisms For Ethanol-Induced Hypertriglyceridaemia, I. Onyesom
Influence Of Fructose On The Mechanisms For Ethanol-Induced Hypertriglyceridaemia, I. Onyesom
Tanzania Journal of Science
Twelve adult albino rabbits with an average weight of 1.42 kg were purchased and divided equally into the normal saline, ethanol and ethanol+fructose-treated groups. The ethanol-treated group orally received 1.5 g (40%) ethanol/kg body weight as single daily dose, while the ethanol +fructose-treated animals also received the same ethanol dose, but were given in addition, 0.25 gfructose/kg body weight after about 10 min of the ethanol administration. The normal saline-treated rabbits were given the equivalent amount of normal saline in lieu of ethanol. The animals were exposed to these various treatments along with their usual feeding pattern for a regular …
Performance Of A Sisal Fibre Fixed-Bed Anaerobic Digester For Biogas Production From Sisal Pulp Waste, A. Mshandete, A. K. Kivaisi, M. S. T. Rubindamayugi, L. Björnsson, B. Mattiasson
Performance Of A Sisal Fibre Fixed-Bed Anaerobic Digester For Biogas Production From Sisal Pulp Waste, A. Mshandete, A. K. Kivaisi, M. S. T. Rubindamayugi, L. Björnsson, B. Mattiasson
Tanzania Journal of Science
A single stage anaerobic digester employing a sisal fibre waste fixed bed was studied for biogas production from sisal pulp waste. The fibre was colonized by microorganisms involved in biogas production. The sisal pulp waste to be digested was fed from the top and was sprinkled intermittently with recirculating leachate from the material. Organic loading rates of 0.1-10 kg volatile solids (VS) m-3d-1 could be applied and methane yields in the range of 0.13-0.48 m3 CH4 kg-1 VS added were obtained. The average methane content in the biogas produced from sisal pulp waste was 55%, and the biogas production rate …
The Influence Of Quantization Process On The Performance Of Global Entropic Thresholding Algorithms Using Electrical Capacitance Tomography Data, A. J. Mwambela
The Influence Of Quantization Process On The Performance Of Global Entropic Thresholding Algorithms Using Electrical Capacitance Tomography Data, A. J. Mwambela
Tanzania Journal of Science
In measuring component fraction in multiphase flows using tomographic techniques, it is desirable to use a high speed tomography system capable of generating 100 tomograms per second. The electrical capacitance tomography system in this regard is considered to be the best among the available tomographic techniques. However, due to its inherent limitations the system generates distorted reconstructed tomograms necessitating the use of extra signal processing techniques such as thresholding to minimize these distortions. Whilst thresholding technique has been effective in minimizing distortions, the additional computation associated with the process limits the speed of tomogram generation desired from the system. Further, …
Influence Of Simultaneous Infestations Of Prostephanus Truncatus And Sitophilus Zeamaison The Reproductive Performance And Maize Damage, C P Rugumamu
Tanzania Journal of Science
This study examined the combined effect of Prostephanus truncatus and Sitophilus zeamais infestations on their reproductive performance and on the damage they cause to maize variety ZM 621 with 12.5% moisture content. The specific objective was to determine the number of the insect pests at F1 and F2 and the grain weight losses caused by the simultaneous pests\' infestations of shelled maize in the search for a control strategy. The results showed a change in adult insect numbers from F1 to F2. During single infestation the change in P. truncatus was 47.54% while in simultaneous infestations it was 41.66%. The …
Distribution And Abundance Of The Edible Orchids Of The Southern Highlands Of Tanzania, Ams Nyomora
Distribution And Abundance Of The Edible Orchids Of The Southern Highlands Of Tanzania, Ams Nyomora
Tanzania Journal of Science
All orchids have showy flowers and many are therefore popular as exotic houseplants as well as contributing significantly to eco-tourism. A special attribute of some orchid genera is the production of edible tubers, an attribute that can contradict eco-tourism if harvesting is not done sustainably. Such is the case in the Southern Highlands where for example, Kitulo Plateau has been gazetted to be a National Park but where edible orchid harvesting is a serious conservation problem. Botanically, unsustainable harvesting can mean the loss of important germplasm even before some species are known to exist. A field survey was undertaken for …
Comparative Analysis Of Mercury Content In Human Hair And Cosmetic Products Used In Dar Es Salaam, Tanzania, C P Kinabo
Comparative Analysis Of Mercury Content In Human Hair And Cosmetic Products Used In Dar Es Salaam, Tanzania, C P Kinabo
Tanzania Journal of Science
Total mercury (T-Hg) concentrations were analysed in human hairs and cosmetic products sold in Dar es Salaam Tanzania. The average total mercury (T-Hg) concentrations in the scalp hair of females using mercury based cosmetic creams and soaps ranged from 7.0 ± 0.4 to 880 ± 12 ppm. Highest T-Hg concentrations were found in females who work in beauty hair salons and the lowest concentrations were found among students. The average values in non-cosmetic users were found to be lower, with mercury ranging from 0.57 ± 0.07 to 8.29 ± 1.22 ppm. Analysis of cosmetic products indicated high values, ranging from …
Zooplankton Communities Of Selected Stations Of Lake Victoria, Rk Waya, Ja Mwambungu
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 …
Species Composition And Biomass Estimates Of Zooplankton In Some Water Bodies Within Lake Victoria Basin, Rk Waya, Ai Chande
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 …