Abstract
Based on phytosociological data, a polythetic divisive classification technique resulted in the delineation of eight broad vegetation types in the back-swamp areas of the Maunachira River System of the Okavango Delta, Botswana. A detrended correspondence analysis indicated that water depth was the major environmental factor influencing the distribution of submerged, floating-leaved and tall, emergent species dominated communities. The remaining communities, with relatively distinct boundaries between each of them, were of short emergent species assemblages rooted in peat deposits with a water depth of less than 0.7 m. Their species composition was not related to water depth, conductivity, pH, redox potential, water temperature or total nitrogen or phosphorus concentrations in the water. The relationship between the present day wetland plant community composition and its environment may be masked by long term, biotic, ‘insulating’ processes such as the accumulation of resources during peat formation and clonal plant growth. This insulation process does not lead necessarily to long term community stability as has been previously suggested (Mitsch and Gosselink 1986).
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References
Anderson, R.F.J. 1976. Weather of the Okavango Delta. In: Proceedings of the Symposium on the Okavango Delta and its Future Utilisation. pp. 29–31. Botswana Society, Gaberone.
Birks, H.J.B. and Birks, H.H. 1980. Quaternary Palaeoecology. Edward Arnold, London, 289 pp.
Breen, C.M., Rogers, K.H. and Ashton, P.J. 1988. Vegetation processes in swamps and flooded plains. In: Vegetation of Inland Waters. Handbook of Vegetation Science. 15: 223–248. Edited by J.J. Symoens. Kluwer Acad. Publ., Dordrecht.
Cataldo, D.A., Hardon, M., Schrader, L.E. and Youngs, V.L. 1975. Rapid colormetric determination of nitrate in plant tissue by nitration of salicylic acid. Commun. Soil Sci. Plant Anal. 6: 71–80.
Connell, J.H. and Slatyer, R.O. 1977. Mechanisms of succession in natural communities and their role in community stability and organisation. Amer. Naturalist 111: 1119–1145.
Cooke, H.J. 1976. The palaeogeography of the middle Kalahari of northern Botswana and adjacent areas. In: Proceedings of the Symposium on the Okavango Delta and its Future Utilisation. pp. 21–28. Botswana Society, Gaberone.
Ellery, W.N. 1988. Channel blockages in the northeastern Okavango Delta: the role of Cyperus papyrus L. MSc thesis. Univ. Witwatersrand, Johannesburg. 98 pp.
Ellery, W.N., Ellery, K., McCarthy, T.S., Cairncross, B. and Oelofse, R. 1989. A peat fire in the Okavango Delta, Botswana, and its importance as an ecosystem process. Aft. J. Ecol. 27: 7–21.
Gauch, H.G. 1982. Multivariate Analysis in Community Ecology. Cambridge Univ. Press, Cambridge. 298 pp.
Gibbs-Russel, G.E. and Biegel, H.M. 1973. Report on the botanical collecting trips to Maun and the northern Okavango Delta. Botswana Notes Rec. 5: 154–169.
Glaser, P.H. 1983. Vegetation patterns in the North Black River peatland, northern Minnesota. Can. J. Bot. 61: 2085–2104.
Hill, M.O. 1979a. TWINSPAN — A FORTRAN program for arranging multivariate data in an ordered two-way table by classification of the individuals and attributes. Ithaca, N.Y. Cornell University. 48 pp.
Hill, M.O. 1979b. DECORANA — A FORTRAN program for Detrended Correspondence Analysis and Reciprocal Averaging. Ithaca, N.Y. Cornell University. 30 pp.
Hogg, E.H. and Wein, R.W. 1988. The contribution of Typha components to floating mat buoyancy. Ecol. 69: 1025–1031.
Howard-Williams, C. and Walker, B.H. 1974. The vegetation of a tropical African lake: Classification and ordination of the vegetation of Lake Chilwa (Malawi). J. Ecol. 62: 831–854.
Hutchins, D.G., Hutton, S.M.R. and Jones, C.R. 1976. The geology of the Okavango Delta. In: Proceedings of the Symposium on the Okavango Delta and its Future Utilisation. pp. 13–20. Botswana Society, Gaberone.
Kratz, T.K. and Dewitt, C.B. 1986. Internal factors controlling peatland-lake ecosystem development. Ecol. 67: 100–107.
Lovett-Doust, L. 1981. Population dynamics and local specialization in a clonal perennial (Ranunculus repens). 1. The dynamics of ramets in contrasting habitats. J. Ecol. 69: 743–755.
McCarthy, T.S., Ellery, W.N., Rogers, K.H., Cairncross, B. and Ellery, K. 1986. The roles of sedimentation and plant growth in changing flow patterns in the Okavango Delta, Botswana. S. Afr. J. Sci. 82: 579–584.
Mitsch, W.J. and Gosselink, J.G. 1986. Wetlands. Van Nostrand Reinhold, New York. 539 pp.
Mueller-Dombois, D. and Ellenberg, H. 1974. Aims and Methods of Vegetation Ecology. John Wiley & Sons, Toronto. 547 pp.
Sanville, W.D., Eilers, H.P., Boss, T.R. and Pfleeger, T.G. 1986. Environmental gradients in northwest freshwater wetlands. Environ. Manage. 10: 125–134.
Sculthorpe, C.D. 1967. The Biology of Aquatic Vascular Plants. Edward Arnold, London. 610 pp.
Slack, N.G., Vitt, D.H. and Horton, D.G. 1980. Vegetation gradients of minerotrophically rich fens in western Alberta. Can. J. Bot. 58: 330–350.
Smith, P.A. 1976. An outline of the vegetation of the Okavango drainage system. In: Proceedings of the Symposium on the Okavango Delta and its Future Utilisation. pp. 93–112. Botswana Society, Gaberone.
Spence, D.H.N. 1982. The zonation of plants in freshwater lakes. Adv. Ecol. Res. 12: 37–124.
Stigand, A.G. 1923. Ngamiland. Geogr. J. 62: 401–419.
Thompson, K. 1985. Emergent plants of permanent and seasonally flooded wetlands. In: The Ecology and Management of African Wetland Vegetation. pp. 43–108. Edited by P. Denny. Junk, Dordrecht.
Tinley, K.L. 1973. An ecological reconnaissance of the Moremi Wildlife Reserve, northern Okavango Swamps, Botswana. Okavango Wildlife Society, Cape Town. 146 pp.
Van der Valk, A.G. and Bliss, L.C. 1971. Hydrarch succession and net primary production of oxbow lakes in central Alberta. Can. J. Bot. 49: 1177–1199.
Van der Valk, A.G. and Davis, C.B. 1976. The seed banks of prairie glacial marshes. Can. J. Bot. 54: 1832–1838.
Walker, D. 1970. Direction and rate in some British Post-Glacial hydroseres. In: Studies in the Vegetation History of the British Isles. pp. 117–139. Edited by D. Walker and R.G. West. Cambridge Univ. Press, London.
Wetzel, R.G. and Likens, G.E. 1979. Limnological Analyses. Saunders, London. 357 pp.
Whittaker, R.H. 1970. Communities and Ecosystems. Concepts in Biology Series. MacMillan Co., New York. 157 pp.
Wilson, B.H. 1973. Some natural and man-made changes in the channels of the Okavango Delta. Botswana Notes Rec. 5: 132–153.
Wilson, B.H. and Dincer, T. 1976. An introduction to the hydrology and hydrography of the Okavango Delta. In: Proceedings of the Symposium on the Okavango Delta and its Future Utilisation. pp. 33–48. Botswana Society, Gaberone.
Wright, H.E. Jr., Mann, D.H. and Glaser, P.H. 1984. Piston corers for peat and lake sediments. Ecol. 65: 657–659.
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Ellery, K., Ellery, W.N., Rogers, K.H. et al. Water depth and biotic insulation: Major determinants of back-swamp plant community composition. Wetlands Ecol Manage 1, 149–162 (1991). https://doi.org/10.1007/BF00177289
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DOI: https://doi.org/10.1007/BF00177289