Crete Mediterranean forests

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Crete Mediterranean forests


WWF Terrestrial Ecoregions Collection

The Crete Mediterranean forests are a cornerstone of the ecology of the island of Crete. This island ecoregion, found in the Mediterranean Sea, has been ravaged by human mismanagement, beginning in the Bronze Age. Timber harvesting and the conversion of forest into pastures have altered much of the original landscape of the island. Floral and faunal diversity for this relatively small ecoregion is high, containing three endemic mammal species, Zimmerman's White-toothed Shrew (Crocidura zimmermannii), the Spiny-mouse (Acomys minous), and a wild goat (Capra hircus cretensis). The island also supports a number of rare and endangered birds such as the Lammergeier (Gypaetus barbatus), Golden Eagle (Aquila chrysaetos), and Bonelli’s Eagle (Hieraaetus fasciatus).

Location and general description

300px-Akamas.jpg Akamas Peninsula, Cyprus. Source: Pedro Regato

The Crete Mediterranean forests ecoregion geographically covers a small area, which is restricted to high mountain ranges (Lefka Ori, 2452 metres (m); Idi Oros, 2456 m; Dikti Oros, 2148 m), hills, and low plains of the island (8700 km2). Climatically, the ecoregion is characterized by a sharp altitudinal gradient. Warm and dry low plains have an average annual temperature of about 17 to 19 º C, with total rainfall of less than 300 millimeters (mm) in the southeastern part of the island, while cold and humid higher elevations have average an annual temperature of about nine to thirteen º C with total rainfall of up to 1400 mm. From the geological point of view, the Crete mountain ranges belong to the Alpine orogenic system, characterized by the predominance of Mesozoic and Tertiary sedimentary rocks such as crystalline limestone, marl, sandstone, and conglomerates. Landform is very complex, typified by impressive karstic landforms (deep canyons, such as Samaria Gorge, poljes, and dolines).

The wide altitudinal range of this ecoregion results in several forest zones. The lowest elevations are distinguished by the predominance of sclerophyllous evergreen and semi-deciduous oak forests (Quercus coccifera, Q. brachyphylla), "maquis" of carob (Ceratonia siliqua), junipers (Juniperus phoenicea), and tree-spurge (Euphorbia dendroides). Phoenix teophrasti, one of the two Mediterranean palm species and endemic to Crete and the Datca Peninsula in south-western Turkey, occurs in a few ravines of the easternmost coastal part of the island (e.g. Vai bay).

At medium altitudes, mesophyllous pine forests (Pinus brutia) and holly oak (Quercus coccifera) woodlands are widely spread. The highest elevations host impresive cypress (Cupressus sempervirens) woodlands, where the endemic evergreen maple (Acer sempervirens) frequently grows. In the high mountain elevations, extensive thorny cushion shrublands occur and support many endemic species.

Biodiversity features

The plant endemism rate of this ecoregion is about ten percent from a total indigenous flora of 1600 species. Most of the endemic species are ancient relics, which are mainly found on the three main mountain ranges, mainly Lefka Ori. Among the most significant endemic plants to be mentioned are a rare and very endangered small tree, Zelkova abelicea, as well as Cephalanthera cucullata, Centaurea baldaccii, Campanula hierapetrae, Bupleurum kakiskalae, Bellevalia brevipedicellata, Astragalus idaeus, Arumpurpureospathum, Anchusa caespitosa, Origanum dictamnus, Orchis prisca, and Onobrychis sphaciotica.

While faunal diversity for this ecoregion is significant, endemism is low. Two small mammals are endemic to the island, a shrew (Crocidura caneae) and a spiny-mouse (Acomys minous). The rare and endemic wild goat (Capra hircus cretensis) is still present in few places on the island.

These forests are considered to be an important Center of Bird Diversity. The high mountains are one of the last strongholds of the endangered Lammergeier (Gypaetus barbatus), golden eagle (Aquila chrysaetos), and Bonelli’s eagle (Hieraaetus fasciatus). About 83 bird species are recorded for the island. Three amphibians and twelve reptile species are thought to be native to Crete; none are endemic.

Historic deterioration

Cretanforestatknossos2007.jpg Vestigial Mediterranean forest at Knossos,
showing severe habitat fragmentation.
Source: C.Michael Hogan

Since the Bronze Age, deforestation has taken a toll on Crete's forests. Hogan (2007) traces the prehistory of Knossos in southern Crete, which was one of the major imperial cities of the Minoan civilisation: an empire that reached great heights circa 2200 BC. The same civilisation that produced some of the earliest forms of complex writing conducted deforestation to such an extent that forest resources were already locally scarce in the Middle Minoan Period (circa 2000 BC). The progression of use of lumber products to more energy intenisve masonry suggests an early exploitation of forest products.

Subsequent history of human use of the island has manifested a record of agricultural intensification and overgrazing on all but the most inaccessible and steep forested areas of Crete. The result has produced a highly depauperate and fragmented forest ecosystem of today.

Current status

Crete’s forests have been dramatically reduced in extent across history. Barren land, with almost nonexistent soil cover, and degraded shrublands are the predominant landscapes of the island. During Classic and Medieval times, Crete was an important shipbuilding center and timber exporting country. Cypress timber was once a very valuable resource. The island has seen great fluctuations in population and prosperity, which has resulted in a long history of use and abuse of timber resources. Overgrazing and the setting of fires to produce fresh grassland have contributed to the transformation of large areas of mature forests to degraded shrublands. Today, at least half of the land surface is used for grazing sheep and goats.

Types and severity of threats

There is a high degree of human impact, mainly due to mismanagement of pastures and grazing in mountain areas, growing tourism development in the northern coastal zone (mainly house building), and intensive agriculture in the southern coastal zone (pesticides and land clearance). Concrete production and road construction are devastating large areas of land with significant native habitats. Plant harvesting may be a long-term threat to some endemic plants.

Justification of ecoregion delineation

This ecoregion is equivalent to the DMEER unit of the same name and includes all of the meso-Mediterranean Holm oak forests, wild olive-locust tree formations, meso- to thermo-Mediterranean pine forests, juniper and cypress woodlands and scrub, and oroxerophytic vegetation on the island of Crete.

Further reading

  • For a more terse summary, see the WWF WildWorld profile of the Crete Mediterranean forests.
  • Brigand, L. et al. 1991. Les iles en Mediterranee, enjeux et perspectives. Les Fascicules du Plan Bleu 5. Economica Ed., Paris.
  • Davis, S.D., V.H. Heywood and A.C. Hamilton, editors. 1994. Centres of Plant Diversity. A Guide and Strategy for their Conservation. Volume 1. Europe, Africa, South West Asia and the Middle East. IUCN Publications Unit, Cambridge, U.K. 354 pp.
  • Delanoë, O. et al. 1996. Conservation of Mediterranean Island Plants. IUCN Publication Service, Cambridge. ISBN: 2831703514 * Delaugerre, M and M. Cheylan 1992. Batraciens et Reptiles de Corse. Parc Naturel Regional de Corse. ISBN: 2905468092 
  • Digital Map of European Ecological Regions (DMEER), Version 2000/05 [1] * Gomez Campo, C. 1985. Plant Conservation in the Mediterranean Ecosystems. Junk Ed. Geobotanica 7.
  • Greuter, W. 1975. Die Insel Kreta - eine geobotanische Skizze. Veröff. Geobot. Inst. ETH, Stiftung Rübel, 55. * Heath, M.F. and M.I. Evans, Editors. 2000. Important Bird Areas in Europe: Priority sites for conservation. Vol 2: Southern Europe. BirdLife International, BirdLife Conservation Series No: 8. ISBN: 0946888361
  • Hogan, C.Michael. 2007. Knossos Fieldnotes. The Modern Antiquarian. edl J.Cope * IUCN. 1996. 1996 IUCN Red List of Threatened Animals. IUCN, Publication Service Unit, Cambridge. * Mayer, H. 1984. Wälder Europas. Gustav Fisher Verlag, Stuttgart. * Medail, F. and P. Quezel. 1997. Hotspots Analysis for Conservation of Plant Biodiversity in the Mediterranean Basin. Ann. Missouri Gard. 84
  • Phitos D. et al. 1995. The red data book of rare and threatened plants of Greece. WWF, Athens. * Quezel P. and M. Barbero. 1985. Carte de la végétation potentielle de la région Méditerranéenne. Feuille 1: Mediterranée Orientale. Scale 1:2,500,000. Ed. du Centre Nationale de la Recherche Scientifique, Paris, France.
  • Quezel, P., Editor. 1982. Définition et localisation des écosystèmes méditerranéens terrestres. Ecologia Mediterranea, Marseille. * Quezel, P. 1979. Les écosystemes forestiers crétois er chypriotes. Chroniques intern. RFF, 31. * Rackham, O. and J. Moody. 1996. The making of the Cretan landscape. Manchester Univ. Press. ISBN: 071903647X 
  • Sarà, M. 1998. I Mammiferi delle isole del Mediterraneo. EPOS Ed., Palermo
  • Shackleton, D.M., Editor. and the IUCN/SSC Caprinae Specialist Group. 1997. Wild Sheep and their Relatives. Status Survey and Conservation Action Plan for Caprinae. IUCN, Gland, Switzerland and Cambridge, UK. ISBN: 2831703530 
  • Thirgood, J.V. 1981. Man and the Mediterranean Forest. London Academic Press. ISBN: 0126872503 
  • Water, K.S., and H.J. Gillett. Editors. 1998. 1997 IUCN Red List of Threatened Plants. Compiled by WCMC. IUCN, Publication Service Unit, Cambridge
  • WWF. 2001. The Mediterranean forests. A new conservation strategy. WWF, MedPO, Rome.
  • Zohary, M. and G. Orshan. 1966. An outline of the geobotany of Crete. Israel Bot. 14.
  • Zohary, M. 1973. Geobotanical foundations of the Middle East. 2. Bde. Stuttgart, Amsterdam.

Citation

World Wildlife Fund, C. Michael Hogan (2014) Crete Mediterranean forests. Encyclopedia of Earth. National Council for Science and Environment. Washington DC. Retrieved from http://editors.eol.org/eoearth/wiki/Crete_Mediterranean_forests


Disclaimer: This article contains certain information that was originally published by the World Wildlife Fund. Topic editors and authors for the Encyclopedia of Earth have edited its content and added new information. The use of information from the World Wildlife Fund should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.


Table 1. Degree of Protection Country Area Name & Creation Date PA size (ha) % Ecor. Prot. Designation & IUCN Cat. Major Forest Types Greece Samaria 4850 National Park Biosphere Reserve Cypress, Calabrian pine, Plane tree, Holly oak forests (Crete Mediterranean forests)