Anales del Jardín Botánico de Madrid, Vol 66, No 1 (2009)

Vegetation of the gnamma of the Sierra de Guadarrama and La Serena (Spain)

Jorge Baonza Díaz , Spain


Weathering pits are wetlands of geomorphologic and biological interest, but this common fact is obscured by the different names used by biologists, such as the ambiguous name of rock pool. Aquatic or amphibious plant communities are known around the world, principally from SE North-America and Tropical Africa, but few are known from Spain. Here, I study the vegetation of weathering pits from two different localities: La Serena (Southweast Spain) and Sierra de Guadarrama (central Spain). Plant communities change with depth of water and depth of sediment in the weathering pits. Some of them are characterized by Crassula vaillantii or Isoetes velatum.


weathering pits; gnammas; rock pools; vernal pools; ephemeral wetlands; variation of plants communities; depth of water; depth of soil

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Abbayes H. 1946. L’association à Bulliardio vaillantii DC. et Ranunculetum nodiflori L. dans le Massif Armorican. Bulletin de la Société Scientifique de Bretagne 21(1-4): 52-60.

Alexandrowicz, Z. 1989. Evolution of weathering pits on sandstone tors in the Polish Carpathians. Zeitschrift für Geomorphologie 33(3): 275-289.

Adjanohoun, E. 1964. Végétation des savanes et des rochers découverts en Côte d’ivoire Centrale. ORSTOM, Paris. 250 pp.

Baonza Díaz, J. 2008a. Pilas pluviales en las pizarras de La Serena (Badajoz). Cuaternario y Geomorfología (aceptado).

Baonza Díaz, J. 2008b. Comunidades de roquedos graníticos sometidos a escorrentía del piso supramediterráneo de la Sierra de Guadarrama (Madrid, España). Itinera Geobotanica [enviado 7/XII/2007].

Barthlott, W. & Porembski, S. 2000: Vascular Plants on Inselbergs: Systematic overview. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 103-116. Berlin, Heidelberg, New York.

Baskin, J.M. & Baskin, C.C. 1988. Endemism in Rock Outcrop Plant Communities of Unglaciated Eastern United States: An Evaluation of the Roles of the Edaphic, Genetic and Light Factors. Journal of Biogeography 15(5/6): 829-840. doi:10.2307/2845343

Bergmeier, E., 2001. Seasonal pools in the vegetation of Gavdos (Greece) - in situ conservation required. Bocconea 13: 511-516.

Biedinger, N. & Fleischmann, K. 2000. Seychelles. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 277-290. Berlin, Heidelberg, New York.

Biedinger, N., Porembski, S. & Barthlott, W. 2000. Vascular Plants on Inselbergs: Vegetative and Reproductive Strategies. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 117-142. Berlin, Heidelberg, New York.

Bouby, H. 1967. Considérations sur la situation floristique actuelle et la protection des mares de Fontainebleau et leurs abords. Le Monde des plantes 355: 6-11.

Brullo, S. & Minissale, P. 1998. Considerazioni sintassonomiche sulla classe Isoeto-Nanojuncetea. Itinera Geobotanica 11: 263-290.

Brullo S., Giusso del Galdo, G. & Lanfranco E. 2001. A new species of Zannichellia L. (Zannichelliaceae) from Malta. Flora Mediterranea 11: 379-384.

Büdel, B, Becker, U, Follmann, G & Sterflinger, K. 2000. Algae, fungi, and lichens on inselbergs. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 69-90. Berlin, Heidelberg, New York.

Burbanck, M.P. & Platt, R.B. 1964. Granite outcrop communities of the piedmont plateau in Georgia. Ecology 45: 292-306. doi:10.2307/1933842

Burke, A. 2003. The role of Namibian inselbergs in contributing to local and regional plant species richness. Biodiversity and Conservation 12(3): 469-486. doi:10.1023/A:1022491723262

Chan, M.A., Moser, K., Davis, J.M., Southam, G., Hughes, K. & Graham, T. 2005. Desert Potholes: Ephemeral Aquatic Microsystems. Aquatic Geochemistry 11(3): 279-302. doi:10.1007/s10498-004-6274-8

Deil, U. 2005 A review on habitats, plant traits and vegetation of ephemeral wetlands – a global perspective. Phytocoenologia 35(2-3): 533-706. doi:10.1127/0340-269X/2005/0035-0533

Domínguez-Villar, D., Arteaga, C., García-Giménez, R., Smith, E.A. & Pedraza, J. 2008. Diurnal and seasonal water variations of temperature, pH, redox potential and conductivity in gnammas (weathering pits): Implications for chemical weathering. Catena 72: 37-48 doi:10.1016/j.catena.2007.03.018

Duguid, A., Barnetson, J., Clifford, B., Pavey, C., Albrecht, D., Risler, J. & McNellie, M. 2002. Wetlands in the arid Northern Territory. A report to Environment Australia on the inventory and significance of wetlands in the arid NT. Parks and Wildlife Commission of the Northern Territory. Alice Springs.

Fischer, E. & Theisen, I. 2000, Vegetation of Malagasy Inselbergs. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 259-276. Berlin, Heidelberg, New York.

Frahm, J.P. 2000. Bryophytes. In: Porembski, S.S. & Barthlott, W. (ed.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 91-102. Berlin, Heidelberg, New York.

Grillas P., Gauthier, P., Yavercovski, N. & Perennou, C. 2004. Mediterranean Temporary Pools Volume 1 – Issues relating to conservation,functioning and management. Station biologique de la Tour du Valat. 121 pp.

Gröger, A. 2000. Flora and vegetation of inselbergs of Venezuelan Guayana. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 291-314. Heidelberg.

Gröger, A. & Huber, O. 2007. Rock outcrop habitats in the Venezuelan Guayana lowlands: their main vegetation types and floristic components. Revista Brasileira de Botânica 30(4): 599-609.

Hambler, D.J. 1964. The vegetation of granitic outcrops in western Nigeria. Journal of Ecology 52: 573-594. doi:10.2307/2257849

Hardy, F. 2006. Le Bulliardio vaillantii-Ranunculetum nodiflori Des Abbayes 1946 (association à Crassula vaillantii (Willd.) Roth et Ranunculus nodiflorus L.) Existe-t-il vraiment? Monde des Plantes 490: 10-20.

Heilmeier, H., Durka, W., Woitke, M. & Hartung, W. 2005. Ephemeral pools as stressful and isolated habitats for the endemic aquatic resurrection plant Chamaegigas intrepidus. Phytocoenologia 35 (2-3): 449-468. doi:10.1127/0340-269X/2005/0035-0449

Hilton J.L. & Boyd, R.S. 1996. Microhabitat requirements and seed/ microsite limitation of the rare granite outcrop endemic Amphianthus pusillus. Bulletin of the Torrey Botanical Club 123: 189-196. doi:10.2307/2996794

Hopper, S.D., Brown, A.P. & Marchant, N.G. 1997. Plants of Western Australian granite outcrops. Journal of the Royal Society of Western Australia 80(3): 141-158.

Jacobi, C.M., do Carmo, F.F., Vincent, R.C. & Stehmann, R. 2007. Plant communities on ironstone outcrops: a diverse and endangered Brazilian ecosystem. Biodiversity and Conservation 16 (7): 2185-2200. doi:10.1007/s10531-007-9156-8

Jürgens, N. & Burke, A. 2000. The arid scenario: Inselbergs in the Namib Desert are rich oases in a poor matrix (Namibia and South Africa). In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 237-257. Berlin, Heidelberg, New York.

Keeley, J.E. & Zedler, P.H. 1998. Characterization and Global Distribution of Vernal Pools. In: Witham, C.W. & al. (eds.), Ecology, Conservation, and Management of Vernal Pool Ecosystems. Proceedings from a 1996 Conference: 1-14. Sacramento.

Krieger, A., Porembski, S. & Barthlott, W. 2000. Vegetation of seasonal rock pools on inselbergs in the savanna zone of the Ivory Coast (West Africa). Flora 195: 257-266.

Lanfranco, S., 1999. Temporary rainwater rockpools as repositories of biological diversity in the Maltese Islands. 2pp in Faculty of Science, University of Plymouth. Environmental themes in the Mediterranean: a case study of the Maltese Islands.

Lebrun, J. 1947. La végétation de la plaine alluviale au Sud du Lac Edouard. Bruxelles, Inst. des Parcs Nat. du Congo Belge, 2 vols.

Liron M.N. 2002. Biodiversité des mares des platières. Les vasques des grés. Réserve de Biosphère du Pays de Fontainebleau. 3 pp.

Liron, M.N. & Thiry, M. 1999. Forêt de Fontainebleau: les platières gréseuses et leurs écosystèmes. Asociation Philomathique d’Alsace et de Lorraine. Strasbourg. 19 pp.

Matthews, J.F. & Murdy, W.H. 1969. A study of Isoetes common to the granite outcrops of the southeastern Piedmont, United States. Botanical Gazette 130: 53-61. doi:10.1086/336469

McVaugh, R. 1943. The Vegetation of the Granitic Flat-Rocks of the Southeastern United States. Ecological Monographs 13 (2): 119-166. doi:10.2307/1943526

Meikle, R.D. 1959. The batrachian ranunculi of the Orient. Notes from the Royal Botanical Garden of Edinburgh 23:13-21.

Mifsud, S. 2004. Introducing Elatine gussonei. The Aquatic Gardener 17 (4): 8-9.

Molina, J.A. 2005. The vegetation of temporary ponds with Isoetes in the Iberian Peninsula. Phytocoenologia 35(2-3): 219-230. doi:10.1127/0340-269X/2005/0035-0219

Monod, T. 1954. Sur une florule soudanaise hygrophile. Bulletin de l’Institut Francais d’Afrique Noire 16A: 309-320.

Mucina, L., Rutherford, M.C. & Powrie, W. 2006. Inland azonal vegetation. In: Mucina, L. & Rutherford, M.C. (eds.), The vegetation of South Africa, Lesotho and Swaziland: 616-627. SANBI, Pretoria. 804 pp.

Müller, J.V. 2007. Herbaceus vegetation of seasonally wet habitats on inslbergs and lateritic crusts in West and Central Africa. Folia Geobotanica 42: 29-61. doi:10.1007/BF02835101

Müller, J.V. & Deil, U. 2005. The ephemeral vegetation of seasonal and semi-permanent ponds in tropical West Africa. Phytocoenologia 35 (2-3): 327-388. doi:10.1127/0340-269X/2005/0035-0327

Noel, F. 2005. Étude d’une espece menacee en Ile-de-France: example de Ranunculus nodiflorus L. Bulletin de l’Association des Naturalistes de la Vallée du Loing 81(1): 24.

Oksanen, I., Lohtander, K., Paulsrud, P. & Rikkinen, J. 2002: A molecular approach to cyanobacterial diversity in a rock-pool community involving gelatinous lichens and free-living Nostoc colonies. Annales Botanici Fennici 38: 93-99.

Oosting, H.J. & Anderson, L.E. 1939. Plant Succession on Granite Rock in Eastern North Carolina. Botanical Gazette 100 (4): 750-768. doi:10.1086/334828

Ott, S., Elders, U. & Jahns, H.M. 1996. Vegetation of the rockalvar of Gotland – I. Microhabitats and succession. Nova Hedwigia 63 (3-4): 433-470.

Ott, S., Elders, U. & Jahns, H.M. 1997. Vegetation of the rockalvar of Gotland II. Microclimate of lichen-rich habitats. Nova Hedwigia 64 (1-2): 87-101.

Osborne, P.L. & McLachlan, A.J. 1985. The effect of tadpoles on algal growth in temporary, rain-filled rock pools. Freshwater Biology 15(1): 77-87. doi:10.1111/j.1365-2427.1985.tb00697.x

Phillips, D.L. 1982. Life-forms of granite outcrop plants. American Midland Naturalist 107: 206-208. doi:10.2307/2425205

Pignatti, E. & Pignatti, S. 2005. Ephemeral wetland vegetation of Western Australia. Phytocoenologia 35(2-3): 201-218. doi:10.1127/0340-269X/2005/0035-0201

Poirion, L. & M. Barbero, 1965. Groupements à Isoetes velata A. Braun (Isoetes variabilis Le Grand). Bulletin de la Société Botanique de France 112: 436-442.

Porembski, S. 1996. Notes on the vegetation of inselbergs in Malawi. Flora 191: 1-8.

Porembski, S., Barthlott, W., Dörrstock, S. & Biedinger, N. 1994. Vegetation of rock outcrops in Guinea: granite inselbergs, sandstone table mountains, and ferricretes. Remarks on species numbers and endemism. Flora 189: 315-326.

Porembski, S., Brown, G. & Barthlott, W. (1995): An inverted latitudinal gradient of plant diversity in shallow depressions on Ivorian inselbergs. Vegetatio 117: 151-163. doi:10.1007/BF00045506

Porembski, S., Fischer, E. & Biedinger, N. 1997a. Vegetation of Inselbergs, Quarzitic Outcrops and Ferricretes in Rwanda and Eastern Zaire (Kivu). Bulletin du Jardin botanique national de Belgique / Bulletin van de National Plantentuin van België 66(1-2): 81-99.

Porembski, S., Seine, R. & Barthlott, W. 1997b. Inselberg vegetation and the biodiversity of granite outcrops. Journal of the Royal Society of Western Australia 80(3): 193-199.

Porembski, S., Becker, U. & Seine, R. (2000): Islands on Islands: Habitats on Inselbergs. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs. Biotic Diversity of Isolated Rock Outcrops in Tropical and Temperate Regions: 49-68. Berlin, Heidelberg, New York.

Potts, M. 1994. Desication tolerance of prokaryotes. Microbiological Review 58(4): 755-805.

Quarterman, E., Burbanck, M.P. & Shure, D.J. 1993. Rock outcrop communities: limestone, sandstone, and granite. In: Martin, W.H., Boyce, S.G. & Echternacht, A.E. (eds.), Biodiversity of the southeastern United States: Upland Terrestrial communities: 35-86. New York.

Quezel, P. 1998. La végétation des mares transitoires à Isoetes en région méditerranéenne, intérêt patrimonial et conservation. Ecologia Mediterranea 24(2): 111-117.

Raghoenandan, U.P.D. 2000. The Guianas (Guyana, Suriname, French Guiana). In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 315-338. Berlin, Heidelberg, New York.

Raynal, A. & Raynal, J. 1961. Observations botaniques dans la région de Bamako. Bulletin de l’Institut Francais d’Afrique Noire 23A(4): 994-1027.

Raynal-Roques, A. & Jérémie, J. 1980. Un marécage saxicole à Isoetes et Ophioglossum en Guyane française. Adansonia, sér. 2 19(4): 403-412.

Rivas-Martínez, S. 2002. High syntaxa of Spain and Portugal and their characteristic species. Itinera Geobotanica 15(2): 434-696.

Rury, P.M. 1978. A new and unique, mat-forming Merlin’s grass (Isoetes) from Georgia. American Fern Journal 68: 99-108. doi:10.2307/1546480

Rury, P.M. 1985. New locations for Isoetes tegetiformans in Georgia. American Fern Journal 75: 102-104. doi:10.2307/1546267

Safford, H.D. & Martinelli, G. 2000. Southeast Brazil. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 339-389. Berlin, Heidelberg, New York.

Sanz Pérez, E. 1996. Alteración y modelado de las areniscas de las facies Purbeck-Weald del noroeste de la Cordillera Ibérica. Cuaternario y Geomorfología 10(3-4): 47-61.

Sarthou, C. & Villiers, J.F. 1998. Epilithic Plant Communities on Inselbergs in French Guiana. Journal of Vegetation Science 9(6): 847-860. doi:10.2307/3237050

Schiller, P., Heilmeier, H. & Hartung, W. 1997. Abscisic acid (ABA) relations in the aquatic resurrection plant Chamaegigas intrepidus under naturally fluctuating environmental conditions. New Phytologist 136(4): 603-611. doi:10.1046/j.1469-8137.1997.00789.x

Schnell, R. 1952. Végétation et flore des Monts Nimba (Afrique occidentale francaise). Vegetatio 3(6): 350-406.

Seine, R. & Becker, U. 2000. East and Southeast Africa. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 213-235. Berlin, Heidelberg, New York.

Seine, R., Porembski, S. & Barthlott, W. 1999. Diversity and phytogeography of inselberg vegetation in the Zambesian region. In: Timberlake, J. & Kativu, S. (eds.), African Plants: Biodiversity, Taxonomy and Uses, pp. 153-164. Royal Botanic Gardens, Kew.

Shure, D.J. 1999. Granit Outcrops of the Southeastern United States. In: Anderson, R.C., Fralish, J.S. & Baskin, J.M. (eds.), Savannas, Barrens, and Rock Outcrop Plant communities of North America: 99-118. Cambridge.

Torres Ribeiro, K., Opazo Medina, B.M. & Rubio Scarano, F. 2007. Species composition and biogeographic relations of the rock outcrop flora on the high plateau of Itatiaia, SE-Brazil. Revista Brasileira de Botânica 30(4): 623-639.

Trochain, J.L. 1940. Contribution à l’étude de la végétation du Sénégal. Mémoires l’Institut Francais d’Afrique Noire, Paris. 2 vols., 433 pp.

Vidal Romaní, J.R. 1983. El cuaternario en la provincia de La Coruña. Geomorfología granítica. Modelos elásticos de formación de cavidades. Tesis doctoral. Univ. Complutense de Madrid (1985), 2 tomos, 600 pp.

Vidal Romaní, J.R. & Twidale, C.R. 1998. Formas y paisajes graníticos. Universidade da A Coruña, A Coruña. 411 pp.

Viñas, X. 2002. Les cassoletes d’Ardenya. Gavarres 1: 78-79.

Walters, T.W. & Wyatt, R. 1982. The vascular flora of granite outcrops in the Central Mineral Region of Texas. Bulletin of the Torrey Botanical Club 109: 344-364. doi:10.2307/2995981

Watve, A. 2003. Vegetation on rock outcrops in Northern Western Ghats and Konkan region, Maharashtra. Geobios (Jodhpur) 30: 41-46.

Wessels, D.C.J. & Büdel, B. 1989. A rock pool lichen community in northern Transvaal, South Africa: composition and distribution patterns. Lichenologist 21(3): 259-277. doi:10.1017/S0024282989000484

Whitehouse, E. 1933. Plant Succession on Central Texas Granite. Ecology 14(4): 391-405. doi:10.2307/1932661

Wyatt, R. 1997. Reproductive ecology of granite outcrop plants from the south-eastern United States. Journal of the Royal Society of Western Australia 80(3):123-129.

Wyatt, R. & Allison, J.R. 2000. Flora and Vegetation of Granite Outcrops in the Southeastern United States. In: Porembski, S. & Barthlott, W. (eds.), Inselbergs: biotic diversity of isolated rock outcrops in tropical and temperate regions: 409-433. Berlin, Heidelberg, New York.

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