Palaeoecological studies of a 14C-dated, 6 m Livingstone core collected from Lac Ichkeul, N. Tunisia have allowed a palaeosalinity and vegetational history record for the last 3000 years to be derived from pollen, chemical and faunal evidence. The lake has been the subject of at least three different salinity regimes; saline (c. 3000 BP-c. 2000 BP), then brackish - fresh (c. 2000 BP-c. 1500 BP), and finally saline (c. 1500 BP-present). These changes in lake salinity are evaluated in the light of the known causes and the implications for the long-term future of the waterfowl populations discussed. An already disturbed Mediterranean woodland dominated by Quercus (cf. Q. suber) and Pinus (possibly P. halepensis) with a significant amount of Phillyrea characterizes the catchment vegetation from c. 3000 BP. From c. 1900 BP a degree of stabilization and regeneration occurs as woodland reinvades and ruderal indicators decline. However, from c. 1400 BP disturbance recommences and Quercus ilex pollen is seen for the first time. This is followed by further woodland interference resulting in the initial rise of Pistacia, but even this is eventually replaced by grassland as intensive cultivation of the Ichkeul catchment for Olea and winter wheat occurs.
Anadón, P., De Deckker, P. and Julià, R.1986: The Pleistocene lake deposits of the NE Baza Basin (Spain): salinity variations and ostracod succession. Hydrobiologia143, 199-208.
2.
Arambourg, C., Arenes, J. and Depape, G.1949: Contribution a l'étude des flores fossiles quaternaires de l'Afrique du Nord. Archives Musée Naturelle Histore11, 1953.
3.
Amould, M.1949: Mouvements epirogéniques récents en Tunisie. Compte Rendu Sommaire Socièté Géologique de France1949, 201-204.
4.
Ben Tiba, B. and Reille, M.1982: Recherches pollenanalytique dans les montagnes de Kroumirie (Tunisie septentrionale): Premiers résultats. Ecologia Mediterranea8, 75-86.
5.
Bonniard, F.1934: Les Lacs de Bizerte: Étude de geographie physique . Revue Tunisienne17, 93-143.
6.
Bradshaw, J.S.1957: Laboratory studies on the rate of growth of the foraminifer Streblus beccarii (Linné) var tepida (Cushman). Journal of Paleontology31, 1138-47..
7.
Brun, A.1983: Étude palynologique des sédiments marins Holocènes de 5000 B.P. à l'Actuel dans la Golfe de Gabès (Mer Pélagienne). Pollen et Spores25, 437-60.
8.
— 1989: Microflores et paléovégétations en Afrique du Nord depuis 30,000 ans. Bulletin Socièté Géologique de France8, 25-33.
9.
Burne, R.V., Bauld, J. and De Deckker, P.1980: Saline lake charophytes and their geological significance . Journal of Sedimentology and Petrology50, 281-93.
10.
Cann, J.H. and De Deckker, P.1981: Fossil Quaternary and living foraminifera from athalassic (non-marine) saline lakes, southern Australia. Journal of Paleontology55, 660-70.
11.
Chaumont, M.1956: Étude hydrologique du basin versant du Lac Ichkeul pendant l'annee agricole 1955-56. Bureau de l'Inventaire des Resources Hydrauliques. 38 pp.
12.
Chevassut, G. and Quezel, P.1956: Contribution à l'étude des groupements végétaux des mares temporaires a Isoetes velata et de dépressions humides à Isoetes hystrix en Afrique de Nord. Bulletin de la Societe d'Histoire Naturelle de l'Afrique du Nord47, 59-73.
13.
Conservation Course1977: A management plan for the proposed Parc National de l'Ichkeul, Tunisia. University of London: Report Series no. 10, Conservation Course.
14.
Cwynar, L.C., Burden, E. and McAndrews, J.H.1979: An inexpensive sieving method for concentrating pollen and spores from fine-grained sediments. Canadian Journal of Earth Sciences16, 1115-20.
15.
Daniels, G.F.1975: The ecology of the Charophyte, Lamprothamnium papulosum J. Groves. Unpublished B.Sc. thesis, University College London.
16.
Debazac, E.F.1959: La végétation forestière de la Kroumirie. Revue des Eaux et Forêts, 16, 1-131.
17.
De Deckker, P.1981: Ostracods of athalassic saline lakes. Hydrobiologia81, 131-44.
18.
Emberger, L.1930: La vegetation de la region mediteraneene. Essai d'une classification des groupements végétaux. Revue Generale Botanique43, 641-62, 705-29.
19.
Ennabli, M.1967: Contribution a l'étude hydrogeologique de la Plaine de Mateur. Université de Paris: Thèse deFaculté des Sciences .
20.
Ericsson, B.1973: The cation content of Swedish post-glacial sediments as a criterion of paleosalinity. Geologiska Foreningens i Stockholm Förhandlingar95, 181-220.
21.
Fay, M.1980: The vegetation of IchkeulTunis: US Peace Corps report to Direction des Forêts.
22.
Flemming, N.C.1978: Holocene eustatic changes and coastal tectonics in the northeast Mediterranean: implications for models of coastal consumption . Philosophical Transactions of the Royal Society, London289, 1362, 405-58.
Hoenisch, U., Mestrovic, S., Schoenenberger, A. and Shroder, P.1970: Le Chêne Zéen (Q. faginea) en Kroumirie (Tunisie du Nord) . Bibliographie Foresti£re Tunisienne6, 1-30.
25.
Hollis, G.E.1986: The modelling and management of the internationally important wetland at Garaet el Ichkeul, Tunisia. IWRB Special publication No. 4, Slimbridge: International Waterfowl Research Bureau.
26.
Kidson, C.1982: Sea level changes in the Holocene. Quaternary Science Reviews1, 121-51.
27.
Kirk, D.1983The plant associations of Djebel Ichkeul, Northern Tunisia in relation to site factors and conservation implications. Unpublished MSc thesis, University College London.
28.
Lamb, H.F., Eicher, U. and Switsur, V.R.1989: An 18,000 year record of vegetation, lake level and climatic change from Tigalmamine, Middle Atlas, Morocco. Journal of Biogeography16, 65-74.
29.
Lemoalle, J.1983: Le Lac Ichkeul - Elements de l'hydroclimat en 1981-1982 . Rapport de l'INSTOP, Tunis, Mimeo.
30.
Le Houérou, H.N.1982: Impact of man and his animals on Mediterranean vegetation . In Di Castri, F., Goodall, D.W. and Specht, R.L., editors, Ecosystems of the world 11: Mediterranean type shrub-lands , New York: Springer .
31.
Malcuit, G.1960: L'isoetion en corse. Montpellier : Monograph of Faculty of Sciences.
32.
Moore, P.D., Webb, J. and Collinson, M.E.1991: Pollen analysis. Oxford: Basil Blackwell.
33.
Oukad, A.1982: Evolution sédimentologique et caractères géochimiques des depôts récents de l'Ichkeul. Thèse du Doctorat, Université de Perpignan, Perpignan.
34.
Reille, M.1976: Analyse pollinique de sediments post-glaciares dans le Moyen Atlas et le Haut Atlas Marocains: premiers r6sultats. Ecologia Mediterranea2, 153-70.
35.
— 1977: Contribution pollenanalytiques à l'histoire Holocène de la végétation des Montagnes du Rif (Maroc Septentrional). Inqua Bulletin50, 53-76.
36.
— 1979: Analyse pollinique du lac de Sidi Bou Rhaba, littoral Atlantique (Maroc). Ecologia Mediterranea4, 61-65.
37.
Ritchie, J.C.1984: Analyse pollinique des sédiments Holocènes supérieurs des Hauts plateaux du Maghreb Oriental. Pollen et Spores26, 489-96.
38.
Rose, F.1981: The wild flower key - British Isles and N. W. Europe . London: Frederick Warne.
39.
Schoenenberger, A.1970: Les groupements de la forêt de Chêne Zéen (Q. faginea) . Bibliographie Forestière Tunisienne3, 1-56.
40.
Scott, D.A.1980: A preliminary inventory of wetlands of international importance for waterfowl in W Europe and N Africa. Slimbridge : International Waterfowl Research Bureau, IWRB Special Publication 2.
41.
Shackleton, J.C., van Andel, T.H. and Runnels, C.N.1984: Coastal palaeogeography of the central and western Mediterranean during the last 125000 years and its archaeological implications . Journal of Field Archaeology11, 307-14.
42.
Stevenson, A.C.1985: Studies in the vegetational history of SW Spain. I. Modern pollen rain in the Doñana National Park, Huelva. Journal of Biogeography12, 246-68.
43.
Stevenson, A.C. and Battarbee, R.W.1991: Palaeoecological and documentary records of recent changes in Garaet el Ichkeul: a seasonally saline lake in NW Tunisia. Biological Conservation58, 275-95.
44.
Stevenson, A.C. and Harrison, RJ1992: Ancient forests in Spain. A model for land-use and dry forest management in SW Spain from 4000 BC to 1900 AD. Proceedings of the Prehistoric Society58, 227-47.
45.
Teeter, J.1965: Effects of NaCl on sago pondweed. Journal of WildlifeManagement29, 838-45.
Verhoeven, J.T.A.1979: The Ecology of Ruppia-dominated communities in western Europe. I: Distribution of Ruppia representatives in relation to their autoecology . Aquatic Botany6, 197-268.
48.
Vita-Finzi, C.1986: Recent earth movements: an introduction to neotectonics . London: Academic Press.
49.
Weinstein, M.1982: The influence of slope direction on the pollen spectra . Pollen et Spores23, 380-87.
50.
West, R.G.1980: The Pre-glacial Pleistocene of the Norfolk and Suffolk coasts. Cambridge: Cambridge University Press.
51.
Wright, H.E., McAndrew, J.H. and Van Zeist, W.1967: Modern pollen rain in western Iran and its relation to plant geography and Quaternary vegetational history. Journal of Ecology55, 415-53.
