Abstract
The main river supplying Lake Naivasha, Kenya, the Malewa, drains a catchment given over to largely subsistence cultivation and animal husbandry. The lake itself is the focus for an intensive horticultural industry based upon irrigation from the lake. The Malewa, however, is relatively independent of the impact of industry, and so its contribution to eutrophication of the lake was evaluated. Two periods of study, a very wet-dry and a `normal' wet-dry season showed that the river contribution of phosphorus led to a total phosphorus loading of 1.4 g m−2 lake surface ann−1 in the very wet period compared to 0.2 in the `normal'. Chlorophyll `a' in the open water of the lake was significantly related to soluble reactive phosphorus. The lake is now eutrophic by normal limnological criteria.
Similar content being viewed by others
References
Ahlgren, I., T. Frisk & L. Kamp-Nielsen, 1988. Empirical and theoretical models of phosphorus loading, retention and concentration vs. lake trophic state. Hydrobiologia 170: 285–303.
Biswas, S., 1972. Ecology of phytoplankton of the Volta lake. Hydrobiologia 39: 277–288.
Boar, R. R., D. M. Harper & C. Adams, 1999. Biomass allocation in Cyperus papyrus in a tropical wetland, Lake Naivasha, Kenya. Biotropica 31: 422–421.
Bootsma, H. A., 1993: Spatio-temporal variation of phytoplankton biomass in Lake Malawi, Central Africa. Verh. int. Ver. Theor. Angew. Limnol. 25: 882–886.
Carlson, R. E., 1977. A trophic state index for lakes. Limnol. Oceanogr. 22: 361–368.
Cronberg, G., 1997. Phytoplankton in Lake Kariba 1989–1990. In Moreau, J. (ed.), Advances in the Ecology of Lake Kariba. Univ. of Zimbabwe Publication, Harare: 66–101.
Cooke, G. D., E. B. Welch, S. A. Peterson & P. R. Newroth, 1993. Restoration and Management of Lakes and Reservoirs, 2nd edn. Lewis Publishers Boca Raton: 548 pp.
Eccles, D. H., 1974. An outline of the physical limnology of Lake Malawi (Lake Nyasa). Limnol. Oceanogr. 19: 730–742.
Gaudet, J. J., 1979. Seasonal changes in nutrients in tropical swamp water. J. Ecol. 67: 953–981.
Hecky, R. E., 1993. The eutrophication of lake Victoria. Verh. int. Ver. Theoret. Angew. Limnol. 25: 39–48.
Hinga, G., 1973. Phosphate sorption capacity in relation to properties of several types of Kenyan soil. East African Agricultural and Forestry Journal 38: 400–404.
ILEC, 1994. Data book of the World Lakes Environments 2 Africa and Europe. International Lake Environment Committee (ILEC), Kosatu, Japan 852.
Jenkin, P. M., 1936. Reports on the Percy Sladen Expedition to some Rift Valley lakes in Kenya 1929. VII. Summary of the ecological Results. Ann. Magazine Nat Hist 9: 133–181.
Jones, R. A. & G. F. Lee, 1982. Recent advances in assessing impact of phosphorus loads on the eutrophication related water quality. Wat. Res. 16: 503–515.
Kalff, J., 1983. Phosphorus limitation in some tropical African Lakes. Hydrobiologia 138: 161–176.
Kalff, J. & S. Watson, 1986. Phytoplankton and its dynamics in two tropical lakes: a tropical and temperate zone comparison. Hydrobiologia 138: 161–176.
Kalff, J. & D. Brumelis, 1993. Nutrient loading, wind speed and phytoplankton in a tropical African lake. Verh. int. Ver. Theor. Angew. Limnol. 25: 860.
Kilham, P. & S. S. Kilham, 1990. Endless summer: internal loading processes dominate nutrient cycling in tropical lakes. Freshwat. Biol. 23: 379–389.
Kratzer, C. R. & P. L. Brezonik, 1981. A Carlson-type trophic state index for nitrogen in Florida lakes. Wat. Res. Bull. 17: 713–717.
Lee, G. F., R. A. Jones & W. Rast, 1980. Availability of phosphorus to phytoplankton and its implications for phosphorus management strategies. In Loehr R. C., C. S. Martin & W. Rast (eds), Phosphorus Management strategies of Lakes. Ann Arbor Science, Ann Arbor: 259–308.
Lehman, J. T., 1996. Pelagic food webs of the East African Great Lakes. In Johnson T. C. & E. O. Odada (eds), The Limnology, Climatology, and Paleoclimatology of the East African Lakes. Gordon & Breach Amsterdam: 281–301.
Lennox, S. D., R. H. Foy, R. V. Smith & C. Jordan, 1997. Estimating the contribution from agriculture to the phosphorus load in surface water. In Tunney H., O. T. Caton, P. C. Brookes & A. E. Johnston (eds), Phosphorus Loss from Soil to Water. CAB International: 55–75.
Mackereth, F. J. H., J. Heron & J. F. Talling, 1989. Water analysis. Freshwater Biological Association, Windermere, U.K.: 120 pp.
McDougall, B. K. & G. E. Ho, 1991. A study of eutrophication of North lake Western Australia. Wat. Sci. Technol. 23: 163–173.
Melack, J.M., 1976. Limnology and Dynamics of Phytoplankton in Equatorial African Lakes. PhD thesis, Duke University, Durham: 453 pp.
Moyo, N. A. G., 1997. Lake Chivero: a Polluted Lake. Harare: IUCN & University of Zimbabwe Publications.
OECD, 1980. Eutrophication of Waters: Monitoring, Assessment and Control. Organisation for Economic Co-operation and development. Paris: 154 pp.
Nyandat, N., 1981. The primary minerals in some Kenya's topsoil and their significance to inherent soil fertility. East Africa Agriculture and Forestry Journal 46: 71–76.
Payne, I., 1984. Tropical Lakes and Rivers. Butterworths, London.
Ryding, S. O. & W. Rast, 1989. The Control of Eutrophication of Lakes and Reservoirs. Vol. 1. Man and the Biosphere series, UNESCO, Paris.
Talling, J. F., 1966. The annual cycle of stratification and phytoplankton growth in Lake Victoria (East Africa). Int. Rev. ges. Hydrobiol. 51: 545–621.
Talling, J. F., 1986. The seasonality of phytoplankton in African lakes. Hydrobiologia 138: 139–160.
Talling, J. F. & I. B. Talling, 1965. The chemical composition of African Lakes waters. Int. Rev. ges. Hydrobiol. 50: 421–463.
Talling, J. F., 2001. Environmental controls on the functioning of shallow tropical lakes. Hydrobiologia 458: 1–8.
Thornton, J. A. & W. K. Nduku, 1982. Lake McIlwaine. Dr W. Junk Publishers, The Hague: 251 pp.
Thornton, J. A., 1987a. Nutrients in African lake ecosystems: do we know all? Journal of Limnological Society of South Africa 12: 25–43.
Thornton, J. A., 1987b. Aspects of eutrophication management in tropical/sub-tropical regions. Journal of the Limnological Society of South Africa 13: 25–43.
Toerien, D. F., 1975. South African eutrophication problems: a perspective. Water Pollution Control 74: 134–142.
Twinch, A. J., 1986. The phosphorus status of sediments in a hypereutrophic impoundment. (Hartbeespoort Dam): implications for eutrophication management. Hydrobiologia 135: 23–34.
UNEP-IETC, 1999. Planning and Management of Lakes and Reservoirs: An Integrated Approach to Eutrophication. Technical Publication Series Issue 11, Osaka/Shiga: 375 pp.
Vollenweider, R. A., 1968. Scientific Fundamentals of Eutrophication of Lakes and Flowing Waters, with Particular Reference to Nitrogen and Phosphorus as Factors in Eutrophication. OECD Paris, DAS/C31/68.27.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kitaka, N., Harper, D.M. & Mavuti, K.M. Phosphorus inputs to Lake Naivasha, Kenya, from its catchment and the trophic state of the lake. Hydrobiologia 488, 73–80 (2002). https://doi.org/10.1023/A:1023362027279
Issue Date:
DOI: https://doi.org/10.1023/A:1023362027279