Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-13T08:44:53.520Z Has data issue: false hasContentIssue false
  • English
  • Français

Mineral nutrient flow from an inselberg in south-western Nigeria

Published online by Cambridge University Press:  10 July 2009

Augustine O. Isichei ,
Alan J. Morton  and
Friday Ekeleme
Augustine O. Isichei
Affiliation:
Department of Botany, Obafemi Awolowo University, Ile-Ife, Nigeria
Alan J. Morton
Affiliation:
Imperial College, Silwood Park, Ascot, Berks, SL5 7PY, UK
Friday Ekeleme
Affiliation:
Department of Botany, Obafemi Awolowo University, Ile-Ife, Nigeria
Get access Rights & Permissions [Opens in a new window]

Abstract

In a study carried out to find out if inselbergs enrich their surroundings with nutrients via drainage, amounts of total nitrogen, nitrate-nitrogen and potassium in rainfall, drainage from bare rock patches and vegetation mats on an inselberg in south-western Nigeria were measured over one year. 43.3 kg ha−1 total nitrogen, 4.8 kg ha−1 nitrate-nitrogen and 10.7 kg ha−1 potassium were recorded in rainfall for the year of study. The amount of total nitrogen in drainage from bare rock was 79% of that in rainfall whilst that in drainage from vegetation mats was 29% of the rainfall amount. The respective values for nitrate-nitrogen were 57% and 13%; for potassium they were 90% and 38%.

It was assumed that the loss of nutrients as water drains through vegetation mats and over bare patches was due to absorption by plants and soil in the mats and lichens in the bare patches. It was therefore concluded that there was no net enrichment of rainwater with nutrrients as it flows over inselberg slopes. There is, however, a funelling of water along with contained nutrients from the inselberg to the surrounding areas. This funnelling is additional to the nutrients and rainfall incident on these surrounding areas and may account for the vegetation around inselbergs being more lush than vegetation in the same area but further away from the inselbergs.

A simple modelling approach was used to assess potential nutrient outflow from inselbergs. The model shows that discharge of nutrients from the edges of inselbergs increases linearly with inselberg diameter. The model further shows that if nutrient funnelling only affects an area near to the edge of the inselberg then nutrient addition is several times higher than would be expected from rainfall deposition alone.

Keywords

enrichmentinselbergnutrientsflow simulationsouth-western Nigeriarunoff
Type
Research Article
Information
Journal of Tropical Ecology , Volume 6 , Issue 4 , November 1990 , pp. 479 - 492
Copyright
Copyright © Cambridge University Press 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

LITERATURE CITED

Agboola, A. A. 1979. Soils of the Nigerian forest zone and their response to cultivation. In Okali, D. U. U. (ed.). The Nigerian rainforest ecosystem. MAB/UNESCO, Nigeria.Google Scholar
Allen, S. E., Grimshaw, H. M, Parkinson, J. A. & Quarmby, C. 1974. Chemical analysis of ecological materials. Black well Scientific Publications, Oxford.Google Scholar
Awodoyin, R. O. 1986. Some aspects of the ecology and biology of Tephrosia bracteolata. Unpublished M.Sc. Thesis, University of Ife, De-Ife. Nigeria.Google Scholar
Ayodele, O. J. 1986. Phosphorus availability in savanna soils of western Nigeria. Tropical Agriculture (Trinidad) 63:297–300.Google Scholar
Bromfield, A. R. 1969. Uptake of phosphorus and other nutrients by maize in western Nigeria. Experimental Agriculture 5:91–100.CrossRefGoogle Scholar
Brown, D. H. 1976. Mineral uptake by lichens. Pp. 419–439 in Brown, D. H., Hawksworth, D. L. & Bailey, R. H. (eds). Lichenology: progress and problems. Academic Press, London, New York and San Francisco.Google Scholar
Duncan, E. R. 1974. Weather information from the University oflfe. Faculty of Agriculture Research Bulletin No. 2. University of Ife Press, Nigeria.Google Scholar
Hambler, D. J. 1964. The vegetation of granitic outcrops in western Nigeria. Journal of Ecology 52:573–594.CrossRefGoogle Scholar
Heathcote, R. G. & Stockinger, K. R. 1970. Soil fertility under continuous cultivation in northern Nigeria II. Responses to fertilizers in the absence of organic manures. Experimental Agriculture 6:345–350.CrossRefGoogle Scholar
Isichei, A. O. & Longe, A. P. 1984. Seasonal succession in a small isolated rock dome plant community in western Nigeria. Oikos 43:17–22.CrossRefGoogle Scholar
Jones, E. 1960. Contribution of rainwater to the nutrient economy of soils in northern Nigeria. Nature (London) 188:432.CrossRefGoogle Scholar
Jones, M. J. & Bromfield, A. R. 1970. Nitrogen in rainfall at Samaru, Nigeria. Nature (London) 277:86.CrossRefGoogle Scholar
Jones, M. J. & Wild, A. 1975. Soils of the East African savanna. Technical Communication No. 55, Commonwealth Bureau of Soils, Harpenden.Google Scholar
McTainsh, G. H. & Walker., 1982. Nature and distribution of harmattan dust. Zeitschrift für Geomorphologie 26:417–435.CrossRefGoogle Scholar
Muoghalu, J. I. & Isichei, A. O. 1987. Seasonal cycling of nitrogen, phosphorus and potassium in isolated vegetation mats on an inselberg in south western Nigeria. African Journal of Ecology 25:265–278.CrossRefGoogle Scholar
Nye, P. H. 1961. Organic matter and nutrient cycles under moist tropical forest. Plant and Soil 13:333–346.CrossRefGoogle Scholar
Ocan, O. 1985. Personal Communication. Department of Geology, University of Ife, De-Ife, Nigeria.Google Scholar
Okeya, O. 1977. Phosphorus fertilizer needs of Nigerian soils as measured by chemical and greenhouse methods. Unpublished M.Phil. Thesis, University of Ibadan, Nigeria.Google Scholar
Richards, P. W. 1957. Ecological notes on West African vegetation I. The plant communities of the Idanre Hills, Nigeria. Journal of Ecology 45:467–577.CrossRefGoogle Scholar
Robertson, G. P. & Rosswall, T. 1986. Nitrogen in West Africa: The regional cycle. Ecological Monographs 56:43–72.CrossRefGoogle Scholar
Roose, E. J. 1974. Influence du type de plante et du niveau de fertilisation sur la composition des eaux de drainage en climat tropical humide. Communication XIII, Journées de I'Hydraulique Paris, Rapport 13.Google Scholar
Sanhueza, E., Guenca, G., Gomez, M. J., Herrera, R., Ishizaki, C, Marti, T. & Paolini, J. 1988. Characterization of the Venezuela environment and its potential for acidification. Pp. 197–255 in Bodhe, H. & Herrera, R. (eds). Acidification in tropical countries. Scope 36. John Wiley & Sons.Google Scholar
Servant, J., Delmas, R., Rancher, J. & Rodriquez, M. 1984. Aspects of the cycle of inorganic nitrogen compounds in the tropical rainforest of the Ivory Coast. Journal of Atmospheric Chemistry 1:391–401.CrossRefGoogle Scholar
Smyth, A. J. & Montgomery, R. F. 1962. The soils and land use of Central Western Nigeria. The Government Printer, Ibadan.Google Scholar
Syers, J. K. & Iskander, I. K. 1973. Pedogenetic significance of lichens. Pp. 1225–1245 in Ahmadjian, V. & Hale, M. E. (eds). The lichens. Academic Press, New York.Google Scholar
Tel, D. A. & Rao, P. V. 1982. Automated and semi-automated methods for soil and plant analysis. Manual Series No. 7, HTA, Ibadan, Nigeria.Google Scholar
Thornton, I. 1965. Nutrient content of rainwater in the Gambia. Nature (London) 205:1025.CrossRefGoogle Scholar
Wild, A. 1971. The potassium status of soils in the savanna zone of Nigeria. Experimental Agriculture 7:257–270.CrossRefGoogle Scholar
Williams, M. E. & Rudolph, E. D. 1974. The role of lichens and associated fungi in the chemical weathering of rock. Mycologia 66:648–660.CrossRefGoogle Scholar