Western acidophilous garrigue
Quick facts
Red List habitat type | code RLF6.1b |
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Threat status | |
Europe | Least Concern |
EU | Least Concern |
Relation to |
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Source | European Red List habitat factsheet |
European Red List of habitats reports | |
European Red List of habitats (Excel table) |
Summary
Xerophytic shrub communities of Mediterranean nano-phanerophytes with rolled or densely hairy leaves, rich in aromatic compoundsdominated by Cistaceae, Labiatae and sometimes by spiny brooms (Genista spp. ) that are always seral stages of forests or high-scrubs (mostly Quercetea ilicis); distributed from the thermo- to the lower supra- mediterranean vegetation belts with semi-arid to subhumid bioclimatic conditions, always in acidic, silicate-derived soils, excluding ultramafic substrata with alkaline reaction. These communities occur on shallow, frequently eroded soils with very acidic raw organic matter (mor type humus) throughout the Western Mediterranean subregion. Their range has been expanded due to human disturbances, namely the destruction of woodlands, and subsequent burning, grazing and agriculture. After abandonment of agricultural fields, after burning or after management of forest landscapes in Mediterranean bioclimates these communities act primarily as pioneer woody vegetation, being composed mostly of R-strategists, partly summer-deciduous seeder shrubs, which are also radiation-prone (heliophilous). As long as the disturbance regimes are kept (fire, tilling) shrub encroachment might occur and successional processes halt at the garrigue stage for a long time; hence the garrigues may have a quasi-permanent character. Garrigues are characterized by high taxa diversity and also a great bio-coenotical and biogeographical differentiation, harboring many endemics. There are two main groups of communities following the nature of the substratum: those on hard silicate (Lavanduletalia stoechadis) rocks and those on loose-sand dunes and palaeodunes (Stauracantho-Halimietalia commutati). Several subtypes (alliances) may be recognized according to biogeography in the span of western Mediterranean region of Europe:
1. Cistion ladaniferi: garrigues of Cistus spp. and Lavandula stoechas at the thermo- to the supra- mediterranenan oceanic bioclimatic belts distributed to the north-central-Levantine Iberia, south coast of France, up to Italy to the coast of Liguria.
2. Cistion laurifolii: garrigues dominated by Cistus laurifolius and Lavandula pedunculata s.l. at the meso- to supra-mediterranean semi-continental bioclimatic belts distributed to west-central Iberian..
3. Ulici argentei-Cistion ladaniferi: garrigues dominated by Cistus ladanifer and C. monspeliensis and co-dominated by Lavandula sampaioana (various subsp.), L. luisieri, Genista hirsuta, Ulex borgiae, U.eriocladus, U. argenteus distributed to central south-western Iberian (luso-estremadurensian and betic provinces).
4. Calicotomo villosae-Genistion tyrrhenae: Italo-Thyrrenean garrigues on volcanic substrata at the thermos-mediterranean belt, dominated by Genista tyrrhena, G. cilentina, Erica multiflora, Cistus spp.., Calicotome villosa, Ampelodesmos mauritanica.
5. Teucrion mari: garrigues dominated by Teucrium marum, Stachys glutinosa, Cistus creticus, Phagnalon rupestre subsp. annoticum, Helychrysum italicum subsp. microphyllum, Genista corsica, G. sardoa, G. ephedroides, G. sulcitana, Santolina insularis, Euphorbia cupanii at the meso- to thermos-mediterranean belts of Sardinia and Corsica.
6. Coremation albi: endemic-rich garrigues communities dominated by Stauracanthus genistoides (= S. lusitanicus), S. spectabilis, Halimium halimifolium, H. calycinum, Ulex australis subsp. australis and U. australis subsp. welwitschianus, U. argenteus subsp. subsericeus, Thymus camphoratus, Thymus capitellatus, Thymus albicans subsp. donyanae on consolidated dunes and palaeodunes distributed from the Portuguese coasts to the coasts of Andalusia. This subtype is characterized by the following genera with endemic species: Armeria, Dianthus, Thymus, Avenula and Sideritis (see flora).
Note on the circumscription of the habitat
Due to vagueness and broadness of the historical ‘garrigue’ concept, the circumscription of the habitat F6.1b should become more precise. Thus, we circumscribe the habitat F6.1b to contain typical nano-phaneropytic (dwarf scrub) garrigues, seral of forests, on acidic silicate-derived soils, excluding chamaephytic mountain vegetation and sea-cliff vegetation. Taking Mucina et al. [EuroVegChecklist] (ined.) as syntaxonomic reference, the habitat includes the major part of the Cisto-Lavanduletea stoechadis vegetation class; hence, the following units or syntaxa with physiognomic and ecological affinities to Cisto-Lavanduletea are excluded: chamaephytic cushion scrub vegetation of Corsica Sardinia and Sicily occurring at the upper supra- to mountain- and oro- mediterranean belts assigned to Carici-Genistetea lobelii and Rumici-Astragaletea siculi - only on Mount Etna) is excluded (F7.4b); Armerio sardoae- Genistion salzmanii is excluded (considered Carici-Genistetea lobelii); tall-broom (Genistetea) communities seral of forests are excluded (F3.1c Cytisetea scopario-striati); xerophytic cushion chamaephytic scrub under the influence of salty wind is excluded (F7.1-2 or B3.1-3b: Helichrysetalia italici, Crithmo-Staticetea or Rosmarinetea); Staehlino-Ulicion baetici is excluded due to ultramafic siliceous alkaline substrata (F6.1a Rosmarinetea officinalis); Teucrion mari and Calicotomo villosae-Genistion tyrrhenae are considered separate alliances and are included in F6.1b; any type of vegetation of F5.1/2 (Pistacio-Rhamnetalia alaterni, Quercetea ilicis), namely Quercion fruticosae is excluded. All Cisto-Micromerietea vegetation from the Eastern Mediterranean subregion is excluded, due to strict biogeographic circumscription of the habitat to the Western Mediterranean ; thus, only territories west of Italy, including the Thyrrenian coast, Sicily, Corsica, Sardinia, Malta and the Baleares are included ( the Adriatic coasts of Italy and territories eastwards are not included). All heathland habitats (F4.2) are excluded. Erica multiflora communities on limestone, even if decarbonated are excluded (Cisto eriocephali-Ericion multiflorae, Cisto-Micromerietea or Rosmarino-Ericion multiflorae, Rosmarinetea). Those communities including E. multiflora on substrata other than limestone are included. Semi- nitrogen or salt prone shrub vegetation is also excluded (F6.8a - Pegano-Salsoletea class).
Indicators of good quality:
As acidic garrigues are considered seral vegetation stages of woodlands, their maintenance in the landscape mosaic depends on the persistence of disturbance: cutting, fire, grazing and agricultural abandonment. Due to the pioneer character of this vegetation type, primary colonization stages after bare ground are species-poor basal communities lacking most specialized plants and poccessing less conservation value. Meta-stability of the garrigues stage for some time is necessary to reach coenotic saturation, i.e. defined by the presence of its full characteristic set of bio-indicators. Thus, as most garrigues follow plowing in managed forest-agricultural context, some patches are to be kept without disturbance for greater time. As much as more characteristic-indicator species are present, the greater the value of the communities.
In general, short periods between plowing should be avoided (< 15 years). In a greater time span, garrigues may be replaced by taller woody vegetation due to progressive ecological succession. The later should be taken on account when managing a landscape mosaic.
Threat status
Synthesis of Red List assessment
EU | |
Red List Category | Red List Criteria |
Least Concern | - |
Europe | |
Red List Category | Red List Criteria |
Least Concern | - |
Confidence in the assessment
Pressures and threats
- Agriculture
- Agricultural intensification
- Crop change
- Intensive mixed animal grazing
- Sylviculture, forestry
- Artificial planting on open ground (non-native trees)
- Removal of forest undergrowth
- Grazing in forests/ woodland
- Natural System modifications
- Lack of fires
- Reduction or loss of specific habitat features
- Natural biotic and abiotic processes (without catastrophes)
- Species composition change (succession)
Habitat restoration potential
Trends in extent |
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Average current trend in quantity |
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Stable | Stable |
EU28 | EU28+ |
Trends in quality |
|
Average current trend in quality |
|
Stable | Stable |
EU28 | EU28+ |
Conservation and management needs
List of conservation and management needs
- No measures
- No measures needed for the conservation of the habitat/species
- Measures related to agriculture and open habitats
- Other agriculture-related measures
Distribution
Geographic occurrence and trends
EU28 | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
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France mainland | Present | unknown | Unknown | Unknown |
Corsica | Present | unknown | Unknown | Unknown |
Italy mainland | Present | 473 | Decreasing | Stable |
Sardinia | Present | 473 | Decreasing | Stable |
Sicily | Present | 473 | Decreasing | Stable |
Portugal mainland | Present | 797 | Unknown | Increasing |
Spain mainland | Present | 8075 | Decreasing | Decreasing |
EU28 + | Present or presence uncertain | Current area of habitat (Km2) | Recent trend in quantity (last 50 years) | Recent trend in quality (last 50 years) |
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Extent of Occurrence, Area of Occupancy and habitat area
Extent of Occurrence (EOO) (Km2) | Area of Occupancy (AOO) | Current estimated Total Area | Comment | |
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EU28 | 2032900 | 2319 | 9345 | |
EU28+ | 2319 | 9345 |
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).