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Characterization Of Iron Sulfides Form Lake Victoria Gold Field, Jwa Kondoro, Ca Kiwanga Dec 1996

Characterization Of Iron Sulfides Form Lake Victoria Gold Field, Jwa Kondoro, Ca Kiwanga

Tanzania Journal of Science

Iron sulphides form the Lake Victoria gold field have been characterized using Mossbauer spectroscopy. Thirteen iron sulphide samples have been categorized into four groups depending on which of the following phases is dominant: monoclinic pyrrhotite, hexagonal pyrrhotite, pyrite or non sulphide phases. A discussion on the characterization of the different phases is given in the paper

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Dispersion Of Heavy Metals Along Msimbazi River Basin In Dar Es Salaam, Jwa Kondoro Dec 1996

Dispersion Of Heavy Metals Along Msimbazi River Basin In Dar Es Salaam, Jwa Kondoro

Tanzania Journal of Science

Several locations of Msimbazi River, a prominent river basin passing through the urban area of Dar es Salaam into the Indian Ocean were sampled for about six months. The sampled specimens of water and sediments were investigated for the extent of heavy metal pollution using atomic Absorption Spectrophotometry (AAS) and X-Ray Fluorescence analysis (XRF) techniques. The major elements of interest in this study were Pb, Cd, Zn, Cu and Cr. Water analysis showed low concentrations for most of the elements. However, sediments showed significant concentration level in various stretches of the river basin for certain elements. The report analyses distribution …

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Aerosol Composition As A Function Of Particles Size, Y. I. A. Koleleni, R. Van Grieken Dec 1993

Aerosol Composition As A Function Of Particles Size, Y. I. A. Koleleni, R. Van Grieken

Tanzania Journal of Science

Analysis of air particulate matter for various particle diameters 0.25-0.5 mm: 0.5-1 mm; 1-2 mm; 2-4 mm; and 4-8 were performed to investigate the contribution of both fine and coarse particles in environmental content. The abundance in the highest percentage concentration relative to particle diameters has shown interesting diagonal pattern with most of the elements ranging within 0-2%; 0.20%; 20-40%; 40-70%: and 70-100% respectively for different particle sizes. For the lowest percentage concentration range it is within 0-20%. In general the sum of elemental concentration provides a significant important result as far as pollution studies are concerned.

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The Use Of Rainfall Patterns In Predicting Population Densities Of Multimammate Rats, Mastomys Natalensis, H. Leirs, R. Verhagen, W. Verheyen Mar 1990

The Use Of Rainfall Patterns In Predicting Population Densities Of Multimammate Rats, Mastomys Natalensis, H. Leirs, R. Verhagen, W. Verheyen

Vertebrate Pest Conference Proceedings: 14th (1990)

During 3 years we studied a population of multimammate rats, Mastomys natalensis (Smith 1834), in Morogoro, Tanzania. Data were collected in both removal and capture-recapture schemes. We present evidence that patterns of growth and reproduction were related to onset and abundance of rains. This partially explains differences in densities. Additionally, we investigated available literature data and related them with climatological data. A scenario is presented which enables us to predict how densities of multimammate rats may evolve in the following year and whether there will be a risk of outbreaks. The use and implications of this scenario in planning control …

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Rodent Control In East Africa, William R. Smythe Mar 1986

Rodent Control In East Africa, William R. Smythe

Vertebrate Pest Conference Proceedings: 12th (1986)

The nations of East Africa consist of Ethiopia, Somalia, Kenya, Uganda, Tanzania, Malawi, Mozambique and Zimbabwe. They encompass a widely varied topography, from coral strands to snow-capped mountains, rain forests to deserts, and tropical to temperate. In all these areas where soil and rainfall patterns permit, agricultural crops are grown. For the most part farming is of a subsistence nature being small single family plots. These farms make up to 90% of the farming in most of the East African nations. There are large farms in Kenya and Zimbabwe generally confined to the temperate uplands. Elsewhere there are large government …

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The Influence Of Salinity On Larval Development And Population Dynamics Of Anopheles Merus Dönitz (Diptera: Culicidae), F. W. Mosha, C. M. Mutero Jan 1982

The Influence Of Salinity On Larval Development And Population Dynamics Of Anopheles Merus Dönitz (Diptera: Culicidae), F. W. Mosha, C. M. Mutero

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Variations in density of adults of Anopheles merus Dön. in Jimbo Village on the Kenya Coast were found to be correlated both with rainfall and with salinity at their breeding sites. Densities started to increase at the beginning of the rains when several breeding sites were formed. This was followed by a decline in numbers resulting mainly from the decrease in salinity in the semi-permanent breeding sites. A second rise occurred after the end of the rains, corresponding with an increase in salinity in the semi-permanent breeding sites due to evaporation. Peak density coincided with salinities of 30–50% sea water …

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The Role Of F.A.O. In Vertebrate Pest Problems, H.R. Shuyler Mar 1974

The Role Of F.A.O. In Vertebrate Pest Problems, H.R. Shuyler

Vertebrate Pest Conference Proceedings: 6th (1974)

Since 1947, when FAO began its involvement in vertebrate pest problems, its role has gradually expanded. Through short-term Consultants, Experts, Regional and Headquarters Officers, it advises Member Countries about vertebrate pest control needs and opportunities, fulfills requests for assistance suggesting needed modifications, and guides and reports on assistance rendered. Assistance may involve one or more international specialists for a few weeks up to national and regional projects of several years' duration. In cooperation with WHO it sponsors meetings of specialists, develops rodenticide specifications for international commerce, and has published rodent bibliographies covering 1950 to 1969.

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Elements Of Tanzanian Coastal Planning, James J. Griffin May 1973

Elements Of Tanzanian Coastal Planning, James J. Griffin

Marine Affairs Theses and Major Papers

The purpose of this paper is to examine aspects of a Coastal Zone Plan as it applies to the Republic of Tanzania with its differences from and similarities to, the United States coastal zone planning experience. Possibly, as a result, some feeling for the problem of organizational concepts and approaches, as well as the current need for Tanzanian coastal zone management will emerge.

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External States And The Indian Ocean: The Potential For Confrontation, James P. Cartwright May 1972

External States And The Indian Ocean: The Potential For Confrontation, James P. Cartwright

Marine Affairs Theses and Major Papers

A study of the common interests of internal and external states in the Indian Ocean and identification of the methods, and their potential for confrontation, employed by external powers in pursuit of their interests. The historical interests of external powers in the Indian Ocean are depicted. Common interests, which have commanded the attention of internal states and external powers during recent years, are identified. The Indian Ocean is divided into five regions, each region characterized by the aforementioned common interests. The assets, mutual relations and interests of the littoral states comprising each region are described. The interests and methods of …

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