de B. Austin, C.

Held, A. C.

Trollope, L. A.

Trollope, W. S. W.

English

University of Kentucky

University of Kentucky UKnowledge International Grassland Congress Proceedings 21st International Grassland Congress / 8th International Rangeland Congress Prescribed Burning Based on Range Condition in the Okavango Delta Ramsar Site in Botswana, Africa W. S. W. Trollope Working On Fire‐International, South Africa L. A. Trollope Working On Fire‐International, South Africa C. de B. Austin Working On Fire‐International, South Africa A. C. Held Working On Fire‐International, South Africa Follow this and additional works at: https://uknowledge.uky.edu/igc  Part of the Plant Sciences Commons, and the Soil Science Commons This document is available at https://uknowledge.uky.edu/igc/21/1-3/29 The 21st International Grassland Congress / 8th International Rangeland Congress took place in Hohhot, China from June 29 through July 5, 2008. Proceedings edited by Organizing Committee of 2008 IGC/IRC Conference Published by Guangdong People's Publishing House This Event is brought to you for free and open access by the Plant and Soil Sciences at UKnowledge. It has been accepted for inclusion in International Grassland Congress Proceedings by an authorized administrator of UKnowledge. For more information, please contact UKnowledge@lsv.uky.edu. 瞯 ]128　 瞯 　 Multifunctional Grasslands in a Changing World 　 Volume Ⅰ 　Grasslands/Rangelands Resources and Ecology ——— Ecology of Grasslands/RangelandsPrescribed burning based on range condition in the Okavango Delta Ramsar site in Botswana ,AfricaW .S .W . T rollope , L .A . T rollope , C .de B . A ustin & A .C . HeldWorking On Fire‐International , 38 Durban Street , Fort Beau f ort , 5720 , South A f rica . E‐mail : w in f ire＠ p rocomp .co .z aThe Okavango Delta located in north western Botswana in southern Africa is one of the world摧s largest remaining inland wetlandecosystems that is protected under the Ramsar Convention . The frequency and severity of fires are perceived to be a threat tothe conservation and wise use of the Delta and provided the motivation for the formulation of a fire management plan for thearea . The vegetation in the Ramsar Site comprises the Permanent and Seasonal Swamps and Burkea , Mopane and A caciaWoodlands . The development of simple and practical quantitative criteria describing the ecological condition of the vegetationthat could be used to identify areas that should be considered for prescribed burning was an important requirement for the firemanagement plan and comprised the following guidelines :１ .Burning is ecologically acceptable if the grass sward is in a climax and/or sub‐climax stage dominated by Decreaser and/ orIncreaser I grass species as a means of maintaining the biodiversity and potential of the grass sward to produce grazing for bothdomestic livestock and wildlife . When in this ecological condition the grass sward is resistant to the negative effects of thisextreme form of defoliation . Conversely burning should not be applied when the grass sward is in a pioneer condition dominatedby Increaser II grass species in order to allow it to develop to a more productive and species diverse stage dominated byDecreaser grass species ( T rollope , １９９９) .２ .Burning is ecologically acceptable , if the grass sward is in a moribund and/or unpalatable condition , as a means of restoringthe vigour of the grass sward and allowing new nutritious regrow th to occur . Field experience indicates that when the standingcrop of grass ≥ ４ ０００ kg / ha in African grasslands and savannas then the grass sward has become moribund and/ or unacceptableto grazing animals and needs to be defoliated by burning or some other means ( T rollope , １９９９) .While no techniques were available for assessing the condition of the Permanent Swamps results of field surveys in the othervegetation types showed that the Seasonal Sw amps and portions of the Burkea Woodlands were the only vegetation units thatshould be considered for controlled burning , based on the proportion of Decreaser and/ or Increaser I grass species . In terms ofgrass fuel loads , only the Seasonal Swamps had extensive areas where the grass sward was in a moribund condition and shouldbe considered for controlled burning .An assessment of the Permanent Swamps dominated by extensive communities of Cy perus p apy rus ( papyrus) and Phragmitessp p . ( reeds) indicated they had extremely high fuel loads capable of generating high intensity fires but were highly resistant toburning because the growing points of the plants are either inundated by water or are growing in moist soil . While it can beaccepted that fire is a natural and necessary factor of the environment in this vegetation type , research is necessary to provideinformation for formulating a fire regime suitable for management purposes in this plant community .ReferencesT rollope , W .S .W . , (１９９９) . Veld burning in different vegetation types : Savanna . In : N .M . Tainton . Veld Management inSouth Africa . University Natal Press , Pietermaritzburg , ２３６‐２４２ .T rollope , W .S .W . , T rollope , L .A . , Austin , C .de Bruno , Held , A .C . , Emery , A . , Hines , C .J .H . , ( ２００６ ) . A firemanagement plan for the Okavango Delta Ramsar Site in Botswana . Final Report . Dept . Forestry & Range Resources ,Botswana Government , Gaberone , Botswana : １‐２０７ .

Prescribed Burning Based on Range Condition in the Okavango Delta Ramsar Site in Botswana, Africa

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Prescribed Burning Based on Range Condition in the Okavango Delta Ramsar Site in Botswana, Africa

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