Title
Gaditanian-Baetic wild olive forests (Olea europaea subsp. oleaster) with Tamus communis on clay soils
Geographical distribution
Country/territory
Spain: hinterland of Cadiz (Baetic Cordilleras, sector Aljibico)
area frequency
2 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Tamo communis-Oleetum sylvestris Benabid 1984.
Structural feature of the main community(ies) (layers, life-forms, etc.)
Olive tree forests (Olea europaea subsp. oleaster) with Pistacia lentiscus, Chamaerops humilis.
Dominant and most frequent species in different layers
Tree layer
Olea europaea subsp. oleaster
Shrub layer
Olea europaea subsp. oleaster, Quercus coccifera, Rhamnus lycioides subsp. oleoides, Chamaerops humilis, Pistacia lentiscus
Lianas
Tamus communis, Asparagus aphyllus, Smilax aspera
Herb layer
Arum italicum, Eryngium tricuspidatum, Phlomis purpurea, Brachypodium retusum, Dactylis glomerata subsp. hispanica, Vinca difformis, Fumaria sepium
Moss layer (incl. lichens)
No details
Diagnostically important species
Olea europea subsp. oleaster; Tamus communis, Arum italicum, Eryngium tricuspidatum
Ecological variants
oleetosum sylvestris; quercetosum suberis: thermo-Mediterranean, subhumid-humid on lessivated soils of siliceous marl with Quercus suber.
Geographical variants (geogr. differential species)
No details
Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
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Adjoining climax and permanent vegetation (with numbers of mapping units)
Quercus ilex subsp. rotundifolia forests (J3, J38), cork oak forests (J35, J36), salt vegetation (P24), moist and alluvial forests (U30, U31).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
Dense scrub with Rosa sempervirens etc.; degraded scrub: Phlomis purpurea, Ulex baeticus subsp. scaber, Asperula hirsuta, Globularia alypum; pioneer forest scrub: Asparago aphylli-Calicotometum villosae on siliceous marl; thornwood scrub: Asparago albi-Rhamnetum oleoides; Cistaceae scrub: Calicotomo villosae-Genistetum lanuginosae on siliceous marl; broom scrub: Asperulo hirsutae-Ulicetum scabri; tomillares: Teucrio lusitanici-Corydothymetum capitati.
grassland (meadows, pastures, herb-rich communities)
Pastures: Brachypodium retusum, Catananche lutea, Dactylis glomerata subsp. hispanica. Nitrophilous community: Echinopo strigosi-Notobasetum syriacae, Bupleuro lancifolii-Ridolfietum segeti, Kickxio lanigerae-Chrozophoretum tinctoriae.
arable land (characteristic weed communities)
Almost 100% in agricultural use: Cereal, sunflowers, cotton (cotton particularly on hydromorphic or pseudogley soils).
settlements (typical ruderal vegetation)
---
Site conditions of the mapping unit
Landscape type, geomorphology
plains with impervious soils
Altitudinal belt and/or altitudinal range
thermo- and meso-Mediterranean
Geology (bedrock)
fluviatile sediments (Pleistocene); Tertiary , Palaeozoic
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
blackish or dark-chestnut-coloured Andalusian black soils with a high content of expansive clay minerals (sometimes over 50 % of the mineral substance); loamy-clayey, silicate chalky clay; (chromic vertisols; stony humic and calcic cambisols)
soil texture
loamy-clayey, stony
soil moisture, water balance
periodically moist to moderately dry
soil reaction
weakly acidic
soil fertility
oligo-mesotrophic, mesotrophic
Climate incl. local climate
climate type (following Walter & Lieth)
IV3, IV(III)
average annual temperature
17-19 °C
average annual precipitation
350-400 mm
average temperature of the warmest month
23-25 °C
average temperature of the coldest month
8-12 °C
local climate or other climatic peculiarities
subhumid-humid climate.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
Only in a few pasture forests (dehesas) in the province of Cádiz have some forest-stages of the succession series remained: Tamo-Oleetum sylvestris, Asparago albi-Rhamnetum oleoides, Asperulo hirsuti-Ulicetum scabri.
endangered communities, species worthy of protection in natural vegetation
Due to the nearly complete conversion into arable land the remnants should be conservational objects of the highest rank.
causes of endangerment
Large-scale agriculture.
required measures for protection and restitution
Protection of the greatly endangered semi-natural remnants.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
No details
of characteristic substitute communities worthy of protection
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Most important references (author, year)
Benabid 1984; Peinado Lorca & Rivas-Martínez (Ed.) 1987; Perez Latorre, Galan de Mera, Deil & Cabezudo 1996; Perez Latorre, Nieto Caldera & Cabezudo 1993; Rivas-Martínez 1987; Rivas-Martínez, Fernández Lousa, Díaz González, Fernández-González & Costa 1990
Compiled by
V. Voggenreiter based on documents by S. Rivas-Martínez; A. Penas Merino and L. Herrero Cembranos
