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Information on water quality and pollution is generally buried in private files and records and hence inaccessible to the general public. Poor organisation of reports in many departmental libraries makes the situation worse.
University theses are only available at the university and have proved less readily available to people outside the university community.
2. 7 Recommendations for future work
2.7.1 Methods quality, comparability
As mentioned earlier, the methods used in the different studies are generally accepted as of good quality. However, it is important to ensure comparability of results from different researcherslaboratories. This can only
be achieved by standardising analytical techniques. In this regard, the following are recommended.
• All laboratories use internationally accepted standard analytical techniques.
• To eliminate systematic errors, regular inter-calibration exercises should be conducted in the
country. Such exercises can be internal between a number of scientists in a laboratory or can be between laboratories.
• The use of internationally recognised reference standards where available. This will eliminate errors
that can arise from use of locally prepared standards.
2.7.2 Geographical Subject coverage and duration of studies
Geographical coverage has been discussed in detail above. Obviously however, some guidance is needed to direct research in areas where gaps in knowledge exit. TCMP is obviously better placed to lead such efforts.
With regard to subject coverage, there is a need for studies on other water contaminants such as pesticides, fertilisers, toxic chemicals and sediments. These have so far received only minimal attention. Agricultural
chemicals in particular, could be important contributor to water pollution in coastal waters that are recipient of input from farm lands, through rain and river run-offs.
To start with, priority should be given to filling gaps in areas where there little or no data available before embarking on long term studies. Consequently short-term, studies should take priority over monitoring programs.
However, this should be decided on a case by case basis, as there are areas that urgently require monitoring of both pollution inputs and its effects on natural environment. Because of the severity of the situation in such areas
as Tanga and Dar es Salaam, these areas qualify for long term monitoring of water quality.
With regard to instrumentation and techniques of sampling, priority should be given to the later as poor sampling techniques and sampling regimes can lead to unnecessary errors as well as render results very difficult to interpret
and hard to relate to management decisions.
2.7.3 Sampling frequency and duration and data analysis
Adequacy of sampling is a prerequisite of any scientific investigation. Most of the studies synthesised in this report had relatively short sampling frequency. This is may be due to the nature of these studies, mostly being
short-term consultancies and students’ projects. It is recommended that in future work more rigorous sampling should be adopted to ensure good representation of the process or aspect under study. However, one should
always be mindful of the logistics involved in taking the samples and their subsequent handling. Sampling frequency is also dependent on the nature of the investigation. For example, a study the water quality of a lagoon
would have a different sampling regime as that of a mangrove region and much more different to that of a point
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source such as a sewage outfall. Moreover, sampling frequencies will depend on whether the study is looking at tidal, seasonal, or even annual variations.
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2.8 REFERENCES
1. Ak’habuhaya, J., 1988: Metal pollution of River Msimbazi, Tanzania.Environment International. 146: 511- 514.
2. Akhabuhaya, J.L., 1989: Pesticides pollution in Tanzania. In Symposium on Environmental Pollution and its Management in Eastern Africa
. Faculty of Science, University of Dar es Salaam. 11- 14 September 1989, pp. 193-194.
3. Allawi, J., Ame, A., Juma, S. and Y.S. Kombo, 1994: Report on communal washing dips study. Unguja Island communal washing dips. Department of Environment, Zanzibar, 6p.
4. Anderson, B., 1994: An environmental monitoring approach to sewage pollution issues along the west coast of Zanzibar. SIT Marine Ecology Tanzania. 31p.
5. Anon., 1994: Inventory of polluted water sources in Tanzania: Pangani water basin. National Environment Management Council NEMC, Dar es Salaam, 16p.
6. Bjork, M., S.M. Mohammed, Bjorklund, M., and A. Semesi, 1995: Corraline algae, important coral reef builders threatened by pollution. Ambio, 24 7-8: 502-503.
7. Bjork, M., S.M. Mohammed, M. Bjorklund, M., and I. Naaslund, 1996: Distribution of coral associated algae at four locations near Zanzibar Town, Tanzania. In M. Bjork, A.K. Semesi, M. Pedersen and B. Bergman,
eds. Current Trends in Marine Botanical Research in the East African Region. Proceedings of the Symposium on the Biology of Microalgae, Macroalgae and Seagrasses in the Western Indian Ocean
. 3-10 December, 1995. University of Mauritius, pp. 347-357.
8. Bliss-Guest, P., 1983: Environmental stress in East Africa, Ambio, 12: 290-295. 9. Bryceson, I., 1983: Pollution of Dar es Salaam Coastal environments by industrial and domestic effluents. In:
Status and Problems of Marine Resources Development in Tanzania. Recommendations and selected papers from the workshop on “The Current State and Development of Marine Sciences in Tanzania.” Zanzibar, 2-8
April, p. 32-41.
10. Bryceson, I., 1984: Phytoplankton and zooplankton production in Tanzanian waters. In the Proceedings of
the NORAD-Tanzania Seminar to Review The Marine Fish Stocks and Fisheries in Tanzania. Mbegani, Tanzania, 6-8 March, p. 9-18.
11. Bryceson, I. and B. Mwaiseje, 1980: An assessment of the ecological impact on the marine environment of
the present and proposed sewerage systems in Dar es Salaam. Report to Howard Humphreys and Partners, 22p.
12. Bryceson, I., 1981: A review of some problems of tropical marine conservation with particular reference to
the Tanzanian coast. Biological Conservation, 20: 163-171. 13. Bryceson, I., 1982: Pollution of Dar es Salaam coastal environments by industrial and domestic effluents. In
Proceedings of the Workshop on the Current State and Development of Marine Sciences in Tanzania .
Institute of Marine Sciences, Zanzibar. 2-8 April, 1982, pp. 32-41. Bryceson, I., 1990: State of the marine environment in the Eastern African Region. UNEP Regional Seas Reports and Studies No. 113.
14. Bryceson, I., T.F. De Souza, I. Jehangeer, M.A.K. Ngoile, and P. Wynter, 1990: State of the marine environment in the Eastern African region. UNEP Regional Seas Reports and Studies No. 113.
