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Water balance and infiltration in a seasonal floodplain in the Okavango Delta, Botswana

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Abstract

Water balance in a seasonal floodplain in the Okavango Delta, Botswana was determined for three years (1997–1999). There was no surface outflow, and infiltration to ground water was very large (4.7–9.7 m during 90–175 days of flooding, or on average 4.6–5.4 cm·d), amounting to 90% of total annual loss of water from the floodplain. At the arrival of the flood, when floodplain ground water was 3–5 m below ground, infiltration was controlled by vertical percolation through the aeration zone and was taking place with rates as high as 1.11–1.74 m during 10 days, or on average 11.1–17.4 cm·d−1. Lateral ground-water flow from the floodplain toward surrounding dryland became the dominant process after the first days of flooding, when the floodplain ground-water table rose to the surface. Lateral ground-water drainage accounted for at least 80% of total infiltration. Direct measurements of infiltration confirmed high rates obtained from the water balance and revealed that the majority of infiltration occurred within a 10-m belt along the shore of the inundated area, with point infiltration rates as high as 42 cm·d−1. The infiltration values are high compared to other large recharge wetlands (e.g., the Everglades, the Hadejia-Nguru) and result from a combination of lack of a low permeability surface layer in the floodplain and strong drainage of floodplain ground water driven by evaporation from the surrounding drylands. High infiltration and lateral ground-water flows have major implications for the Okavango Delta ecology, as they provide water to riparian vegetation, affect floodplain nutrient balance, and are part of the process responsible for immobilization of dissolved minerals.

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Literature Cited

  • Bauer, P. 2004. Flooding and salt transport in the Okavango Delta, Botswana: key issues for sustainable wetland management. Ph. D. Dissertation, ETH Zurich, Zurich, Switzerland.

    Google Scholar 

  • Boring, M. and L. Björkvald. 1999. A minor field study of the infiltration rate on a floodplain in the Okavango Delta, Botswana. Research Report. Göteborg University, Sweden and Harry Oppenheimer Okavango Research Centre, University of Botswana, Botswana.

    Google Scholar 

  • Brunke, M. and T. Gonser. 1997. The ecological significance of exchange processes between rivers and groundwater. Freshwater Biology 37: 1–35.

    Article  Google Scholar 

  • Choi, J. and J. W. Harvey. 2000. Quantifying time-varying ground-water discharge and recharge in wetlands of the northern Florida Everglades. Wetlands 20: 500–511.

    Article  Google Scholar 

  • Cronberg, G., A. Gieske, E. Martins, J. Prince-Nengu, and I. Stenstrom. 1996. Major ion chemistry, plankton, and bacterial assemblages of the Jao/Boro River, Okavango Delta, Botswana: the swamps and flood plains. Archiv für Hydrobiologie. Supplementband. Monographische Beitraege 3: 335–407.

    Google Scholar 

  • Dinçer, T., S. Child, and B. Khupe. 1987. A simple mathematical model of a complex hydrologic system — Okavango Swamp, Botswana. Journal of Hydrology 93: 41–65.

    Article  Google Scholar 

  • Dinçer, T., H. H. Heemstra, and D. B. Kraatz. 1976. The study of hydrological conditions in an experimental area in the seasonal swamp. Technical Note No. 20. UNDP/FAO, BOT/71/706, Gaborone, Botswana.

  • Doorenbos, J. and W. O. Pruitt. 1984. Crop water requirements. Irrigation and Drainage Paper No. 24. FAO, Rome, Italy.

    Google Scholar 

  • Doss, P. K. 1993. The nature and dynamics of water table in a system of non-tidal, freshwater coastal wetlands. Journal of Hydrology 141: 107–126.

    Article  Google Scholar 

  • Ellery, K. and W. Ellery. 1997. Plants of the Okavango Delta. A Field Guide. Tsaro Publishers, Durban, South Africa.

    Google Scholar 

  • Ellery, W. N., K. Ellery, and T. S. McCarthy. 1993. Plant distribution in islands of the Okavango Delta, Botswana: determinants and feedback interactions. African Journal of Ecology 31: 118–134.

    Article  Google Scholar 

  • Freeze, R. A. and J. A. Cherry. 1979. Groundwater. Prentice-Hall, Engelwood Cliffs, NJ, USA.

    Google Scholar 

  • Gieske, A. 1997. Modelling outflow from the Jao/Boro River system in the Okavango Delta, Botswana. Journal of Hydrology 193: 214–239.

    Article  Google Scholar 

  • Goes, B. J. M. 1999. Estimate of shallow groundwater recharge in the Hadejia-Nguru Wetlands, semi-arid northeastern Nigeria. Hydrogeology Journal 7: 294–304.

    Article  Google Scholar 

  • Gumbricht, T., J. McCarthy, and T. S. McCarthy. 2004. Channels, wetlands and islands in the Okavango Delta, Botswana, and their relation to hydrological and sedimentological processes. Earth Surface Processes and Landforms 29: 15–29.

    Article  Google Scholar 

  • Harrington, G. A., P. G. Cook, and A. L. Herczeg. 2002. Spatial and temporal variability of ground water recharge in central Australia: a tracer approach. Ground Water 40: 518–528.

    Article  CAS  PubMed  Google Scholar 

  • Harvey, J. W., J. Choi, and R. H. Mooney. 2000. Hydrologic interactions between surface water and ground water in Taylor Slough, Everglades National Park. p. 22–24, In J. R. Eggleston (ed.) U.S. Geological Survey Program on the South Florida Ecosystem: 2000 proceedings. U.S. Geological Survey Open-File Report 00-49, USGS, Denver, CL, USA.

    Google Scholar 

  • Harvey, J. W., S. L. Krupa, and J. M. Krest. 2004. Ground water recharge and discharge in the Central Everglades. Ground Water 42: 1090–1102.

    Article  Google Scholar 

  • Hayashi, M., G. van der Kamp, and D. L. Rudolph. 1998. Water and solute transfer between a prairie wetland and adjacent uplands, 1. Water balance. Journal of Hydrology 207: 42–55.

    Article  CAS  Google Scholar 

  • Heinl, M., J. Sliva, and B. Tacheba. 2004. Vegetation changes after single fire-events in the Okavango Delta wetland, Botswana. South African Journal of Botany [Online] 70: 695–704.

    Google Scholar 

  • Hoberg, P., M. Lindholm, L. Ramberg, and D. O. Hessen. 2002. Aquatic food web dynamics on a floodplain in the Okavango Delta, Botswana. Hydrobiologia 470: 23–30.

    Article  Google Scholar 

  • Hughes, F. M. R. 1990. The influence of flooding regimes on forest distribution and composition in the Tana River floodplain, Kenya. Journal of Applied Ecology 27: 475–491.

    Article  Google Scholar 

  • Jacobsen, T., A. McDonald, and H. Enggrob. 2005. Integrated Hydrological Model. Okavango Delta Management Plan, Department of Water Affairs, Gaborone, Botswana.

    Google Scholar 

  • Jolly, I. D., G. R. Walker, and K. A. Narayan. 1994. Floodwater recharge process in the Chowilla Anabranch system, South Australia. Australian Journal of Soil Research 32: 417–435.

    Article  Google Scholar 

  • Jones, J. B. and P. J. Mulholland. 2000. Streams and Ground Waters. Academic Press, San Diego, CA, USA.

    Google Scholar 

  • Kgathi, D. L., G. Mmopelwa, and K. Mosepele. 2005. Natural resources assessment in the Okavango Delta, Botswana: case studies of some key resources. Natural Resources Forum 29: 70–81.

    Article  Google Scholar 

  • Krah, M., T. C. McCarthy, P. Huntsman-Mapila, P. Wolski, and K. Sethebe. 2005. Nutrient transport with water, from soil surfaces and local aerosol deposition into the landlocked Okavango Delta, Botswana — a floodplain case study. Wetlands Ecology & Management (in print).

  • LaBaugh, J. W., T. C. Winter, V. A. Adomaitis, and G. A. Swanson. 1987. Hydrology and chemistry of selected prairie wetlands in the Cottonwood Lake area, Stutsman County, North Dakota. U.S. Geological Survey Professional Paper 1431, USGS, Denver, CL, USA.

    Google Scholar 

  • Lamontagne, S., F. W. Leaney, and A. L. Herczeg. 2005. Groundwater-surface water interactions in a large semi-arid floodplain: implications for salinity management. Hydrological Processes 19: 3063–3080.

    Article  CAS  Google Scholar 

  • Lee, D. R. 1977. A device for measuring seepage flux in lakes and estuaries. Limnology and Oceanography 22: 140–147.

    CAS  Google Scholar 

  • Lerner, D. N., A. S. Issar, and I. Simmers. 1990. Groundwater Recharge. A guide to understanding and estimating natural recharge: International Contributions to Hydrogeology, vol. 8. Heise, Hannover, Germany.

    Google Scholar 

  • Maidment, D. R. 1992. Handbook of Hydrology. McGraw-Hill, New York, NY, USA.

    Google Scholar 

  • Marti, E., S. G. Fisher, J. D. Schade, and N. B. Grimm. 2000. Flood frequency and stream-riparian linkages in arid lands. p. 111–136, In J. B. Jones and P. J. Mulholland (eds.) Streams and Ground Waters. Academic Press, San Diego, CA, USA.

    Chapter  Google Scholar 

  • Mbaiwa, J. E. 2003. The socio-economic and environmental impacts of tourism development on the Okavango Delta, north-western Botswana. Journal of Arid Environments 54: 447–467.

    Article  Google Scholar 

  • McCarthy, J., T. Gumbricht, T. S. McCarthy, P. E. Frost, K. Wessels, and F. Seidel. 2004. Flooding patterns in the Okavango Wetland in Botswana between 1972 and 2000. Ambio 7: 453–457.

    Google Scholar 

  • McCarthy, T. S., M. Barry, A. Bloem, W. N. Ellery, H. Heister, C. L. Merry, H. Rother, and H. Sternberg. 1997. The gradient of the Okavango fan, Botswana, and its sedimentological and tectonic implications. Journal of African Earth Sciences 24: 65–78.

    Article  CAS  Google Scholar 

  • McCarthy, T. S., A. Bloem, and P. A. Larkin. 1998. Observations on the hydrology and geohydrology of the Okavango Delta. South African Journal of Geology 101: 101–117.

    Google Scholar 

  • McCarthy, T. S., J. R. McIver, and B. T. Verhagen. 1991. Groundwater evolution, chemical sedimentation and carbonate brine formation on an island in the Okavango Delta swamp, Botswana. Applied Geochemistry 6: 577–595.

    Article  CAS  Google Scholar 

  • Mermillod-Blondin, F., M. Creuze des Chantelliers, P. Marmonier, and M. Dole-Olivier. 2000. Distribution of solutes, microbes and invertabrates in river sediments along a riffle-pool-riffle sequence. Freshwater Biology 44: 255–269.

    Article  CAS  Google Scholar 

  • Meyer, T. 1999. Ecological mappings in the research area of the Harry Oppenheimer Okavango Research Centre, Okavango Delta, Botswana. M. Sc. Thesis. Anhalt Technical University, Anhalt, Germany.

    Google Scholar 

  • Mitsch, W. J. and J. G. Gosselink. 2000. Wetlands. John Wiley & Sons, New York, NY, USA.

    Google Scholar 

  • Mladenov, N., D. McKnight, P. Wolski, and L. Ramberg. 2005. Effects of annual flooding on dissolved organic carbon dynamics within a pristine wetland, the Okavango Delta, Botswana. Wetlands 25: 622–638.

    Article  Google Scholar 

  • Mubyana, T., M. Krah, O. Totolo, and M. Bonyongo. 2003. Influence of seasonal flooding on soil total nitrogen, organic phosphorus and microbial populations in the Okavango Delta, Botswana. Journal of Arid Environments 54: 359–369.

    Article  Google Scholar 

  • Obakeng, O. and A. Gieske. 1997. Hydraulic conductivity and transmissivity of a water-table aquifer in the Boro River system, Okavango Delta. Department of Geological Survey, Lobatse, Botswana.

    Google Scholar 

  • Petermann, T., E. de Nooy, and H. Bendsen. 1988. Thaoge River Project. Evaluation Mission. Molapo Development Project, Department of Agriculture, Maun, Botswana.

    Google Scholar 

  • Ringrose, S. 2003. Characterisation of riparian woodlands and their potential water loss in the distal Okavango Delta, Botswana. Applied Geography 23: 281–302.

    Article  Google Scholar 

  • Sacks, L. A., J. S. Herman, L. F. Konikow, and A. L. Vela. 1992. Seasonal dynamics of groundwater-lake interactions at Doñana National Park, Spain. Journal of Hydrology 136: 123–254.

    Article  CAS  Google Scholar 

  • Scudder, T., R. E. Manley, R. W. Coley, R. K. Davis, J. Green, G. W. Howard, S. W. Lawry, D. Martz, P. P. Rogers, A. R. D. Taylor, S. D. Turner, G. F. White, and E. P. Wright. 1993. The IUCN review of the Southern Okavango Integrated Water Development Project. IUCN, Gland, Switzerland.

    Google Scholar 

  • SMEC. 1987. Study of open water evaporation in Botswana. Snowy Mountains Engineering Corporation, Ministry of Local Government and Lands, Gaborone, Botswana.

    Google Scholar 

  • SMEC. 1989. Ecological zoning of the Okavango Delta. Snowy Mountains Engineering Corporation, Ministry of Local Government and Lands, Gaborone, Botswana.

    Google Scholar 

  • Sophocleous, M. 2002. Interactions between groundwater and surface water: the state of science. Hydrogeology Journal 10: 52–67.

    Article  CAS  Google Scholar 

  • Thompson, J. R. and G. Polet. 2000. Hydrology and land use in a sahelian floodplain wetland. Wetlands 20: 639–659.

    Article  Google Scholar 

  • Tiner, R. W. 1999. Wetland Indicators: a Guide to Wetland Identification, Delineation, Classification, and Mapping. Lewis Publishers, Boca Raton, FL, USA.

    Google Scholar 

  • Turton, A. R., P. J. Ashton, and T. E. Cloete. 2003. An introduction to the hydropolitical drivers in the Okavango River basin, p. 9–30, In A. R. Turton, P. J. Ashton, and T. E. Cloete (eds.) Transboundary Rivers, Sovereignty and Development: Hydropolitical Drivers in the Okavango River Basin. Green Cross International (GCI), Geneva, Switzerland. African Water Issues Research Unit (AWIRU), Pretoria, South Africa.

    Google Scholar 

  • UNDP/FAO. 1977. Investigation of the Okavango Delta as a Primary Water Resource for Botswana. UNDP/FAO, DP/ BOT/71/506, Gaborone, Botswana.

    Google Scholar 

  • Winter, T. C. 1999. Relation of streams, lakes, and wetlands to groundwater flow systems. Hydrogeology Journal 7: 28–45.

    Article  Google Scholar 

  • Winter, T. C., J. W. Harvey, O. L. Franke, and W. M. Alley. 1998. Ground water and surface water: a single resource. U.S. Geological Survey Circular 1139, USGS, Denver, CL, USA.

    Google Scholar 

  • Winter, T. C. and D. O. Rosenberry. 1995. The interaction of groundwater with prairie pothole wetlands in Cottonwood Lake area, east-central North Dakota, 1979–1990. Wetlands 15: 193–211.

    Article  Google Scholar 

  • Woessner, W. W. 2000. Stream and fluvial plain groundwater interactions: rescaling hydrogeological thought. Ground Water 38: 423–429.

    Article  CAS  Google Scholar 

  • Wolski, P. and T. Gumbricht. 2003. Mapping hydrological units in the Okavango Delta. Water and Ecosystem Resources for Regional Development, EU ICA-4-CT-2001010040, Harry Oppenheimer Okavango Research Centre, Maun, Botswana.

    Google Scholar 

  • Wolski, P., M. Murray-Hudson, P. Fernkvist, A. Lidén, P. Huntsman-Mapila, and L. Ramberg. 2005a. Islands in the Okavango Delta as sinks of water-borne nutrients. Botswana Notes and Records 37: 253–263.

    Google Scholar 

  • Wolski, P., H. H. S. Savenije, M. Murray-Hudson, and T. Gumbricht. 2005b. Modelling the hydrology of the Okavango Delta, Botswana. J. Hydrol. (in print).

  • Wolski, P. and H. H. S. Savenije. 2003. Update of conceptual hydrological model of the Delta. Water and Environmental Resources for Regional Development, EU ICA-4-CT-2001-10040, Harry Oppenheimer Okavango Research Centre, Maun, Botswana.

    Google Scholar 

  • WRC. 2003. Maun Groundwater Development Project, Project Review. Water Resources Consultants, Department of Water Affairs, Gaborone, Botswana.

    Google Scholar 

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Correspondence to Piotr Wolski.

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Ramberg, L., Wolski, P. & Krah, M. Water balance and infiltration in a seasonal floodplain in the Okavango Delta, Botswana. Wetlands 26, 677–690 (2006). https://doi.org/10.1672/0277-5212(2006)26[677:WBAIIA]2.0.CO;2

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  • DOI: https://doi.org/10.1672/0277-5212(2006)26[677:WBAIIA]2.0.CO;2

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