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Soil Loss, Hydrological Changes, and Conservation Attitudes, in the Sabi Catchment of Zimbabwe

Published online by Cambridge University Press:  24 August 2009

Raoul F. du Toit
Affiliation:
Research Fellow, Department of Biological Sciences, University of Zimbabwe, P.O. Box MP 167, Mount Pleasant, Harare, Zimbabwe.

Extract

The Communal Lands—occupied by peasant farmers—of the upper catchment of the Sabi River (which drains the southeastern portion of Zimbabwe) are severely deforested, overgrazed, and eroded. Siltation of the river channel has increased the risk of overbank flooding at a downstream irrigation scheme, and a rise in annual outflow from the catchment over the last three decades has additional implications for irrigation development, as well as for the availability of ground-water reserves in the areas of dryland peasant farming.

In a study area within one of the Communal Lands, the average rate of soil loss from fields of gentle slope is estimated to be such that the next generation of peasant farmers will be unable to achieve crop-yields above a very low ‘subsistence’ level. The degraded environment is the inevitable consequence of the expansion of a primitive system of cultivation—in a region of low inherent potential for crop production—under the pressure of rapid population growth. While the peasants are aware of many of the consequences of their exploitative methods of land-use, and recognize the importance of basic conservation measures such as erosion-control terraces, they generally feel that remedial action is beyond their means.

The effective implementation of available technical solutions to the deterioration of the land resources, will depend upon the provision of greater financial incentives for intensified production, as well as upon more positive political influences, than exist at present. The eventual stabilization of the situation is achievable only if population growth is reduced; but much might be done to improve production, and promote conservation, through field research into appropriate farming systems for peasant agriculture in the Sabi catchment and similar environments.

Type
Main Papers
Copyright
Copyright © Foundation for Environmental Conservation 1985

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References

REFERENCES

Anon. (1984). Zimbabwe: from pledge to action. World Conservation Strategy in Action—IUCN Bulletin Supplement (Gland, Switzerland), No. 1, pp. 13.Google Scholar
Bangezhano, C.K. (1983). People-Vegetation Interactions in the Upper Sabi Catchment Area. Unpubl. Thesis, Department of Biological Sciences, University of Zimbabwe: 47 pp.Google Scholar
Barnes, D.L. (1978). Problems and prospects of increased pastoral production in the Tribal Trust Lands. Zambezia, 6, pp. 4959.Google Scholar
Barnes, D.L. & Clatworthy, J.N. (1976). Research in veld and pasture production in relation to the Tribal Trust Lands. Rhodesia Science News, 10, pp. 271–8.Google Scholar
Bates, D.B. (1980). Important innovations introduced by agricultural extension to the tribal farmer over the last twenty years. Rhodesia Science News, 14, pp. 187–90.Google Scholar
Box, G.E.P. & Jenkins, G.M. (1976). Time Series Analysis: Forecasting and Control. Holden-Day, San Francisco, California, USA: xxi + 575 pp., figs & tables.Google Scholar
Caughley, G. (1979). What is this thing called carrying capacity? Pp. 28 in North American Elk: Ecology, Behaviour and Management (Eds Boyce, M.S. & Hayden-Wing, L.D.). University of Wyoming: [not available for checking].Google Scholar
Conex (Department of Conservation and Extension, Rhodesia) (1976). Agro-Ecological Map of Rhodesia, 1:1 Million. Government Printer, Salisbury, Rhodesia: map.Google Scholar
Elwell, H.A. (1980). Design of Safe Rotational Systems. Department of Agricultural, Technical and Extension Services, Salisbury, Zimbabwe: 50 pp., figs & tables (mimeogr.).Google Scholar
Elwell, H.A. & Stocking, M.A. (1982). Developing a simple yet practical method of soil-loss estimation. Tropical Agriculture, 59, pp. 43–8.Google Scholar
Elwell, H.A. & Stocking, M.A. (1984). Estimating soil life-span for conservation planning. Tropical Agriculture, 61, pp. 148–50.Google Scholar
Gapare, R. (1976). Problems in crop production as seen by a Tribal Trust Land farmer. Rhodesia Science News, 10, pp. 249–51.Google Scholar
Geza, S. & Reid, M. (1983). Environmental conservation in Communal Lands, with special reference to grazing lands. Zimbabwe Science News, 17, pp. 148–51.Google Scholar
Grant, P.M. (1970). Restoration of productivity of depleted sands. Rhodesia Agricultural Journal, 67, pp. 131–7.Google Scholar
Grant, P.M. (1976). Peasant farming on infertile sands. Rhodesia Science News, 10, pp. 252–4.Google Scholar
Grant, P.M. (1981). The fertilization of sandy soils in peasant agriculture. Zimbabwe Agricultural Journal, 78, pp. 169–75.Google Scholar
Hoogmoed, W.B. & Stroosnijder, L. (1984). Crust formation on sandy soils in the Sahel, I: Rainfall and infiltration. Soil & Tillage Research, 4, pp. 523.CrossRefGoogle Scholar
Hudson, N.W., Davies, F.G. & Pilditch, A.G. (1964). Final Report of the Sabi Catchment Investigation Team. Federal Department of Conservation and Extension, Salisbury, Southern Rhodesia: 11 pp., appendixes & maps (mimeogr.)Google Scholar
Kay, G. (1975). Population pressure and development prospects in Rhodesia. Rhodesia Science News, 9, pp. 713.Google Scholar
Kennan, P.B. (1980). Agricultural extension in Zimbabwe, 1950–1980. Zimbabwe Science News, 14, pp. 183–6.Google Scholar
Kinsey, B.H. (1983). Forever gained: resettlement and land policy in the context of national development in Zimbabwe. Pp. 92113 in Past and Present in Zimbabwe (Eds Peel, J.D.Y. & Ranger, T.O.). University of Manchester Press: [not available for checking].Google Scholar
Linsley, R.K., Kohler, M.A. & Paulhus, J.L.H. (1982). Hydrology for Engineers. McGraw-Hill, Tokyo, Japan: xx + 508 pp., figs & tables.Google Scholar
Meikle, G. (1982). Soil Erosion of Sabi Catchment and Suggested Remedies. Department of Agricultural, Technical and Extension Services, Harare, Zimbabwe: 6 pp. (mimeogr.).Google Scholar
Mitchell, T.B. (1972). Hydrological cycle in Rhodesia. Pp. 14 in Water in Agriculture. (Rhodesia Agricultural Journal Technical Bulletin No. 15.) Government Printer, Salisbury, Rhodesia: 197 pp., illustr.Google Scholar
Mukundu, M.Z. (1976). Factors limiting increased crop production in Tribal Trust Lands as an extension worker sees them. Rhodesia Science News, 10, pp. 248–9.Google Scholar
Ngara, T., McNaughton, D.L. & Lineham, S. (1983). Seasonal rainfall fluctuations in Zimbabwe. Zimbabwe Agricultural Journal, 80, pp. 149–50.Google Scholar
O'Keefe, P. (1983). The causes, consequences and remedies of soil erosion in Kenya. Ambio, 12, pp. 302–5.Google Scholar
Plowes, D.C.H. (1976). Technical problems of tribal crop production. Rhodesia Science News, 10, pp. 244–7.Google Scholar
Plowes, D.C.H. (1980). The impact of agricultural extension in the eastern tribal areas of Zimbabwe. Zimbabwe Science News, 14, pp. 197200.Google Scholar
Rodel, M.G.W. & Hopley, J.D.H. (1973). Investigation into systems of farming suitable for Tribal Trust Land. Rhodesia Agricultural Journal, 70, pp. 118.Google Scholar
Sharma, T.C. (1984). Hydrological changes in the Kafue Basin. Pp. 1027 in Development on the Kafue Flats: The Last Five Years (Eds Handlos, W.L. & Williams, G.J.). Kafue Basin Research Committee, University of Zambia, Lusaka, Zambia: vi + 78 pp., figs & tables.Google Scholar
Stubbs, A.T. (1977). The Tribal Trust Lands in transition: landuse. Rhodesia Science News, 11, pp. 181–4.Google Scholar
Thompson, J.G. & Purves, W.D. (1978). A Guide to the Soils of Rhodesia. (Rhodesia Agricultural Journal Technical Handbook No. 3.) Government Printer, Salisbury, Rhodesia: vi + 64 pp., map & tables.Google Scholar
Truscott, K. & Pambirei, N.C. (1983). Buhera, Chiweshe Ward: Report of a Socio-economic Survey. Department of Agricultural, Technical and Extension Services, Harare, Zimbabwe: 52 pp. (mimeogr.).Google Scholar
Vincent, V. & Thomas R.G. (1960). An Agricultural Survey of Southern Rhodesia, Part I: Agro-ecological Survey. Government Printer, Salisbury, Southern Rhodesia: viii + 124pp., appendixes & maps, illustr.Google Scholar
Wendelaar, F.E. (1978). Applying the Universal Soil Loss Equation in Rhodesia. Department of Conservation and Extension, Salisbury, Rhodesia: 23 pp. (mimeogr.).Google Scholar
Wenner, C.-G. (1983). Soil conservation in Kenya. (Interview.) Ambio, 12, pp. 305–7.Google Scholar
Wentworth, C.K. (1930). A simplified method of determining the average slope of land surfaces. American Journal of Science, 20, pp. 184–94.CrossRefGoogle Scholar
Whaley, W.R. (1975). Socio-political factors in the management of the ecosystem. Rhodesia Science News, 9, pp. 14–7.Google Scholar
Whitlow, J.R. (1979). A scenario of changes in subsistence landuse and its relevance to the tribal areas of Zimbabwe. Zambezia, 7, pp. 171–90.Google Scholar
Whitlow, J.R. (1980). Environmental constraints and population pressures in the tribal areas of Zimbabwe. Zimbabwe Agricultural Journal, 77, pp. 173–81.Google Scholar
Whitlow, J.R. (1983). Vlei cultivation in Zimbabwe: Reflections on the past. Zimbabwe Agricultural Journal, 80, pp. 123–35.Google Scholar
Whitlow, J.R. (1984). Environment, Land Utilization and Development Prospects in the Peasant Farming Areas of Zimbabwe. University of Keele, Department of Geography, Occasional Paper No. 8: 70 pp., maps.Google Scholar
Wicht, C.L. (1971). The influence of vegetation in South African mountain catchments on water supplies. South African Journal of Science, 67, pp. 201–9.Google Scholar
Wischmeier, W.H. & Smith, D.C. (1978). Predicting Rainfall Erosion Losses: A Guide to Conservation Planning. Agricultural Handbook No. 537, United States Department of Agriculture, Washington, DC, USA: 58 pp., figs.Google Scholar
Wonnacott, T.H. & Wonnacott, R.J. (1981). Regression: A Second Course in Statistics. John Wiley & Sons, New York, NY, USA: xix + 556 pp., figs & tables.Google Scholar