AFRIQUE AUSTRALE SOUTHERN AFRICA Coordinateur Co-ordinator B.R. LIA VIES and/el. M. STRA UGHAN Southern African wetlands including Angola, Botswana, Lesotho, Malawi, Mozambique, Republic of South Africa, Swaziland, Zambia and Zimbabwe Les zones humides de l’Afrique australe incluent Angola, Botswana, Lésotha, flalawi, Mozambique. RQpublique d’Afrique du Sud, Swaziland, Zambie et Zimbabwé Afrique australe '- 340 - INTRODUCTION While southern Africa comprises 10 political divisions, the region may be considered as having four major types of wetland: 1. Temporary pans, with an irregular hydrological regime and long dry periods; 2. River floodplains, with striking annual fluctuations in water level, based on river flood cycles; 3. Large endorheie basins with long-term cyclical fluctuations; 4. Shallow coastal lakes (known as 'vleis' in South Africa), which although relatively stable hydrologically, undergo long-term cyclical fluctuations. Although the topography more or less precludes the formation of inland lakes sensu strictu, there is a small, but important additional category Pound in the high alpine regions of the central-eastern sector of the region: namely, the bogs and sponge sources of the Orange River in Lesotho. There has, in comparison uith many other parts of Africa, been a considerable amount of ecosystem-based research on southern African wetlands, and as such, we have been in the fortunate position to separate a large number of references into individual systems or compact groups of inter-related systems, suc11 as: 8.1, Lake Chilwa; 8.4, the Okavango-Makgadikgadi Swamps; 8.7. the Pongola floodplain; 8.9, St Lucia and 8.8, Lake Sibaya. Other "systems" are more general - the work is sometimes more diffuse - and we have treated them as similar systems within a prescribed geographical sub-region, thus 8.11, western Cape coastal lakes, including Zandvlei, Zeekoevlei and other wetlands near Cape Town; 8.10, the Wilderness lakes of the southern Cape, including Swartvlei, Rondevlei, Groenvlei, Eilandvlei and tangvlei in the Knysna-George region of the south toast of South Africa (sec maps). The Zambezi floodplains and Mozambique wetland systems have been grouped into what is hoped to be a useful amalgamation (8.5). Here, the literature is very widely scattered, with little concentration on the sys tems covered as “ecosys tems”. Therefore. the section covers the Luenha, Barotse, Kafue and Marromeu floodplains of the Zambezi and its tributaries, and Mozambique coastal lakes suc11 as Lagoa Poelela, together with other less important (or less well-known) wetland systems on the Mozambique coastal plain. There are numerous temporary '@pans*' - shallow depressions irrogularly water-filled, with long intervsls of drying (the equivalent of the "sebkhas" of Region 1) - scattereci throughout the more arid regions of southern Africa; in the Kalahari and Namib deserts, Karoo, and central and southern South Africa (sec maps). Here, we had a major problem of treatment, but eventually decided upon grouping them as a special water body type (section 8.3). This, we feel, is justified in SO far as the literature is extremely poor. By bringing them together, we hope to have added some focus on their importance. References which deal with southern Africa as a rahole, or to large sections of the region, have been grouped together in the first part of this bibliography, as 8.0. In addition, reference works which deal with prescribed political divisions (sec maps) have also been separated for ease of use. Thus. Angolan general references fa11 under 8.0.1, Botswanan general references under 8.0.2 and Zimbabwean general references under 8.0.10. The bog and sponge sources OF the orange fa11 under section 8.0.3, Lesotho. As far as reference selection is concerned, we have attempted, as far as possible, to concentrate an references of limnological interest, attempting to avoid papers dealing solely with the systematics of small groups of animals and plants. This has not always worked, and they have necessarily been included in works compiled for individual systems (eg: Lake Chilwa) for completoness. - 341 - Southern Africa TO those familiar with southern African geography, a glance at the systems map imrnediately illustrates the enormous gaps in research and literature available on wetlands of the region. Large pans, such as Etosha have virtually no information base, and certainly there has beeen no study of its functioning; pans in general have already been identified as poosy studied systems. Another major area of neglect concerns the floodplains of the region. Only the Pongola has a reasonable body of literature and data base, while the Zambezi linked systems - excepting the Okavango, Barat-se, Lenha, Kafue, and Marromeu - are little known as systems. Only the Okavango has a relatively large body of literature, but most of it doos not consider ecosystem functioning. On the other hand, the eastern and southern coastal lakes of South Africa have received considerable attention - Lakes Sibaya, St Lucia, Swartvlei and one or two others, as has the large endorheic basin of Lake Chilwa. However, we still have a long way to go before understanding their functioning in detail, and the heavily stressed coastal lakes of the southern and western Cape of South Africa are of particular concern. ACKNOWLLDGEMRNTS This regional compilation was made possible by funds from the South African Council for Scientific and Industrial Research. Since we began the work in August 1981, we have been supportad by a large number of people, who have given unselfishly of their time to provide us with source material, and we would like to warmly acknowledge thefr support: Professor Brian Allanson, Mrs Susan Allanson, Mrs Pat Eva, Dr Amy Jacot Guillarmod, Professor Charles Breen, H Furness, Patrick Reavell, Dr Mike Bruton, Dr Ben van der Waal, Mr M R Steyn, Hr B Hun tley , Kevin and Fiona Rogers, Paul DUtton, P J Ashton, Richard Brooke and Rïcky Taylor. Sources have included the Limnological Society of Southern Africa Bibliography (Rhodes University), the Percy Fitzpatrick Institute for African Ornithology (University of Cape Town), the school of Environmental and Geographical Science (University of Cape Town), the St Lucia Documentation Centre (Natal Parks, Game and Fish Preservation Board) and the South African Water Information Centre of the Council for Scientific and Industrial Research. Brian Marshall in Zimbabwe sent useful material, and a Bibliography on Mozambique work, compiled by Heimo Mikkola, was also of use. Katy Carter provided a most useful critique of content and style which considerably improved this section, as well as providing useful guidelines for the book as a whole. The f irst draft was typed by Leonora Fox, while the second, produced under difficult circumstances, was cheerfully knocked into shape by Janet Longman. The third draft was speedily and efficiently typed by Vicky Herlihy. We would like to acknowledge the support of the South African Council for Scientific and Industrial Research and the encouragement of Graham Noble and Brian Huntley OP the CSIR. Finally, the senior author would like to warmly thank the participants of both the Thonon Les Bains and Tunis workshops, where constructive criticism, advice, encouragement and hospitality was freely given: Mary Burgis, Charles Breen, Pierre Compère, Phillippe Dufour, Henri Dumont, Françoise C;asse, Jacques Lemoalle, Christian Lévêque , Jacques Moreau, Janine Pensaert ,, Jean-Jacques Symoens and Jack Talling. Afrique sustrale - 342 - INTRQDUCTION L’Afrique australe telle qu’elle est consideree ici comprend dix états, en tout ou en partie; on peut y distinguer quatre types principaux de zones humides: 1. Les fnares temporaires a régime hydrologique irrégulier avec de longues périodes de sécheresse; 2. Les plaines d’inondation des rivières, montrant d’importantes variations annuelles de niveau liees aux cycles d’inondation des rivières; 3. Les grands bassins endorhéiques, montrant des fluctuations cycliques à long terme; 4. Les lacs cotiers peu profonds (appelés “vleis,, en Afrique du Sud), qui, bien que relativement stable hydrologiquement, subissent des fluctuations cycliques à long terme. Dans les régions alpines elevées du secteur- centra-oriental, ou la topograhie empeche la formation de lacs interieurs sensu stricto, il existe une catégorie supplémentaire, petite mais importante: les tourbières et les sources spongieuses du fleuve Orange au Lesotho. Par rapport à d’autres parties de l’Afrique, il y a eu, en Afrique australe, de nombreuses recherches sur l’écologie des zones humides, ce qui nous à permis de classer de nombreuses reférences sous divers systèmes individuels ou sous des groupes de systèmes reliés entre eux comme: 8.1, lac Chilwa; 8.4, marais de l’okavango-Makgadikgadi; 8.7, plaine inondée du Pongola; 8.9, St Lucia et 8.8, 3 lac Sibaya. D’autres “systemes,, sont traites d’une manière plus générale comme systèmes semblables appartenant à une sous région géographique determinée ainsi: 8.11, lacs côtièrs occidentaux de l’État du Cap, comprenant Zandvlei, Zeekoevlei et d’outres zones humides voisines de Cape Town; 8.10, lacs du Wilderness au sud de l’état du Cap, comprenant Swartvlei, 1Zondevlei, Groenvlei, Kilandvloi et Langevlei dans la région de Knysna-George de la côte sud d’Afrique du Sud. Les plaines d’inondation du Zambèze et les zones humides du Mozambique ont été rassemblées, dans la section 8.5; ici la littérature est éparse et rarement Concentr&e sur les Qcosystèmes; la section couvre notamment les Plaines d’inondation du bassin du Zambeze et ses affluents (Luenha, Barotse, Kafue et Marromeu), les lacs côtiers du Hozambique comme Lagoa Poelela et d’autres systèmes humides moins importants (ou moins bien connus) des plaines côtieres du Hozambique. 11 existe de nombreuses mares temporaires (“pans’,) dépressions peu profondes, irréguliérement inondees, avec de longs in tervilles d, assèchement (l’équivalent des ,,sebkhas,, de la région 1) dispersees dans les régions les plus arides de l’Afrique australe, dans les deserts du Kalahari et de Namibie, dans le Karoo, et dans le sud et le centre de l’Afrique du Sud.