The physico-chemical characteristics of ten permanently flowing rivers from Kahuzi Biega National Park (Democratic Republic of Congo) were examined in July 2007. Water samples were collected from ten sites between 1800 and 3200 m asl and analyzed for the following chemical parameters: biological oxygen demand, total and carbonate hardness, alkalinity, total phosphorus, nitrogen, nitrate, and ammonia. Discharge, current velocity, temperature, and oxygen saturation were analyzed on site. In general, the chemical parameters revealed relatively low concentrations compared to others rivers in the region. The rivers were cold (10℃ - 15℃), well oxygenated, had low conductivity (generally <100 μS/cm), and had pH values ranging between 5.5 and 7.6. Nitrogen and phosphorus were also low (0.086 - 0.25 μmol/L for phosphorus and 2.21 - 4.25 μmol/L for nitrogen) in all rivers. The main natural sources of nitrogen and other nutriaents are from rain and atmospheric deposition, organic matter decomposition, and fixation of molecular nitrogen from allochthonous inorganic material. In the forested rivers of Kahuzi-Biega National Park the terrestrial and riparian environments are the only sources of nitrogen and phosphorus to the river water.
KeywordsPhysico-ChemicalParametersRiversKahuzi-Biega National Park
G. Marlier, “Recherches Hydrobiologiques Dans les Rivières du Congo Orientale. Etude Ecologique,” Hydro biologia, Vol. 6, No. 3-4, 1952, pp. 225-263. doi:10.1007/BF00053675
K. O. Viets and K. Bottger, “Zur Systematic und Okologie Rheophiler Hydrachnellae (Acari) Zentral Afri kas Teil 1,” Acarologia, Vol. 16, No. 1, 1974, pp. 106 159.
K. Bottger, “Studies on the Productivity of Kalengo Stream in Central Africa,” Archivfür Hydrobiologie, Vol. 75, No. 1, 1975, pp. 1-31.
S. B. Jonnalagadda and G. Mhere, “Water Quality of the Odzi River in the Eastern High Lands of Zimbabwe,” Water Resources, Vol. 35, No. 10, 2001, pp. 2371-2376.
B. Caruso, “A Survey Comparing Streams from Forested and Deforested Watersheds to Assess Impact of Land Use Change on the Northeastern Shore of Lake Tanganyika,” Nyanza Project Report, 2002, pp. 1-4.
H. Eggermont and D. Verschuren, “Impact of Soil Erosion in Disturbed Tributary Drainages on the Benthic in vertebrate fauna of Lake Tanganyika, East Africa,” Bio logical Conservation, Vol. 113, No. 1, 2003, pp. 99-109. doi:10.1016/S0006-3207(02)00353-1
M. Bagalwa, “The Impact of Land Use on Water Quality of the Lwiro River, Democratic Republic of Congo, Central Africa,” African Journal of Aquatic Science, Vol. 31, No. 1, 2006, pp. 137-143.
G. Fryer, and T. D. Iles, “The Cichlid Fishes of Great Lakes of Africa: Their Biology and Evolution,” Olivier & Boyd, Edinburgh, 1972, 641 p.
D. F. E. Thys Van Audenaerde, , E. Coenen, J. Robben and D. Vervoot, “Fishes Research on Lake Kivu,” Royal Africa Museum, Tervuren, 1980.
A. H. Kurt, and E. R. Hecky, “The Late Pleistocene and Holocene Stratigraphy and Paleolimnology of Lakes Kivu and Tanganyika,” Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 61, 1987, pp. 169-197.
G. W. Coulter, “Lake Tanganyika and Its Life,” Oxford University Press, London, 1991.
J. Snoeks, “De Haplochromis-Soorten (Teelostei, Cichli dae) van Het kivemeer: Een & -Taxonomic Revision”, Doctoral thesis, Tervuren, Belgium.
J. P. Kopelke, “Ephemeroptera (Insecta) ausder Emergenz des Zentrafrikanischen Bergbaches Kalengo (Zaire). Teil II: Leptophebiidae, Heptageniidae, Tricorythidae, Caenidae,” Bullettin de la Societe Entomologique Suise, Vol. 54, 1981, pp. 139-156.
P. Steffen, B. Baluku, N. Mulimbwa, S. Amundala, M. Ngera, N. Byamunguand and M. Bisimwa, “Inventaire Systèmatique des Macroinvertébrés de Quelques Cours d’eau du Parc National de Kahuzi Biega (PNKB) et sa Région Adjacente,” Programme—Biodiversité des Eco systèmes Aquatiques et Terrestre du Rift Albertin, 2005, pp. 49-59.
H. B. N. Hynes, “The Biology of Polluted Waters,” Liverpool University Press, Liverpool, 1974.
N. Raj and P. A. Azeez, “Spatial and Temporal Variation in Surface Water Chemistry of a Tropical River, the River Bharathapuzha, India,” Current Science, Vol. 96, No. 2, 2009, pp. 245-241.
M. Meybeck, “River Water Quality: Global Ranges, Time and Space Variabilities, Proposal for Some Redefinitions,” Verhandlungen des Internationalen Verein Limnologie, Vol. 26, 1996, pp 81-96.
S. Kimbadi, A. Vandelannoote, H. Deelstra, M. Mbemba M. and F. Ollevier, “Chemical Composition of the Small Rivers of the North-Western Part of Lake Tanganyika,” Hydrobiologia, Vol. 407, 1999, pp. 75-80. doi:10.1023/A:1003749817147
J. Dubois, “Evolution de la Température, de l’Oxygène Dissous et de la Transparence Dans la Baie Nord du Lac Tanganyika,” Hydrobiologia, Vol. 10, No. 1, 1958, pp 215-240. doi:10.1007/BF00142188
M. Bagalwa, “Environmental impact of Land Use Change on Water Quality of Inflowing Tributaries of Lake Kivu,” Proceeding of 11th World Lakes Conference, Nairobi, 31 October-4 November 2005, pp. 379-383.
M. Mankoto, J. Yamagiwa, B. Steinhauer, N. Mwanza, T. Maruhashi and T. Yumoto, “Conservation of Eastern Lowland Gorilla in the Kahuzi-Biega National Park, Zaire,” University Louis Pasteur, Strasbourg, 1994, pp. 113 122.
A. J. Goodall, “Feeding and Ranging Behaviour of a Mountain Gorilla Group (Gorilla gorilla beringei) in the Tshibinda-Kahuzi Region (Zaire),” Primate Ecology Academic Press, London, 1977, pp. 450-479.
D. F. Murnyak, “Censusing the Gorillas in Kahuzi-Biega National Park,” Biological Conservation, Vol. 21, No. 3, 1981, pp. 163-176. doi:10.1016/0006-3207(81)90089-6
H. L. Golterman, R. S. Clymo and M. A. N. Ohnstad, “Methods for Physical and Chemical Analysis of Freshwaters,” Blackwell Scientific Publication, London, 1978, 213 p.
APHA, “Standard Methods for the Examination of Water and Wastewater,” American Public Health Association, 1989.
R. G. Wetzel and G. E. Likens, “Limnological Analysis,” Springer, Berlin, 2000, 429 p.
M. A. L. Silva, C. F. Calasans, A. R. C. Ovalle and C. E. Rezende, “Dissloved Nitrogen and Phosphorus Dynamics in the Lower Portion of the Paraiba do Sulriver, Campos dos Goytacazes, RJ, Brazil,” Brazilian Archives of Bio logy and Technology, Vol. 44, No. 4, 2001, pp. 385-371.
K. Karume, “Biomass and Hydropower Potential and Demand in the Albertine Rift Region,” Ph.D. Thesis, Makerere University, Uganda, 2006.
P. A. Oluwande, M. K. C. Sridhar, A. O. Bammeke and A. O. Okubadejo, “Pollution Levels in Some Nigeria Riv ers,” Water Research, Vol. 17, No. 9, 1983, pp. 957-963. doi:10.1016/0043-1354(83)90035-0
A. Vandelannoote, H. Deelstra, F. Vyumvuhore, L. Bitetera and F. Ollevier , “The Impact of the River Ntahangwa, the Most Polluted Burundian Tributary of Lake Tanganyika, on the Water Quality of the Lake,” Hydrobiologia, 328, No. 2, 1996, pp. 175-187. doi:10.1007/BF00018713
L. Bennasser, M. Fekhaoui, J. L. Benoit-Guyod and G. Merlin, “Influence de la Mare Sur la Qualité des Eaux du bas Sebou Soumis aux Rejets de la Plaine du Gharb (Maroc),” Water Resources, Vol. 31, 1997, pp. 859-867.
R. E. Hecky, H. Bootsman and M. L. Kingdom, “Impact of Land Use on Sediment and Nutrient Yields in Lake Malawi/Nyassa (Africa),” Journal of Great Lakes Research, Vol. 29, Suppl. 2, 2003, pp. 139-156.
T. P. Karthikeyani, T. P. Velavan and M. Ramesh, “Physico-Chemical and Biological Characterization of the River Shanmuganadhi, Tamil Nadu,” Environment and Ecology, Vol. 20, No. 2, 2002, pp. 482-486.
D. S. Fatoki, P. Gogwana and A. O. Ogunfowokan, “Pollution Assessment in the Keistamma River and It the Impoundment Downstream,” Water SA, Vol. 29, No. 2, 2003, pp. 183-187.
M. Meybeck and R. Helmer, “The Quality of Rivers: From Pristine Stage to Global Pollution,” Paleogeography, Paleoclimatolgy, Palaeo Ecology, Vol. 75, No. 4, 1989, pp. 283-309.
S. W. Nixon, “Remineralization and Nutrient Cycling in Coastal Marine Ecosystems,” University of Rhode Island, Kingston, 1981, pp. 111-138.
S. Dodson, “Introduction to Limnology,” McGraw Hill, New York, 2005, 400 p.
H. L. Golterman, “Physiological Limnology,” Elsivier, New York, 1975, 489 p.
B. Moss, “Ecology of Fresh Waters: Manand Medium,” Blackwell Scientific Publications Ltd., Oxford, 1988, 417 p.