Red List habitat classification > RLF - Heathland and scrub > RLF6.7 Mediterranean gypsum scrub

Mediterranean gypsum scrub

Quick facts

Red List habitat type code RLF6.7
Threat status
Europe Least Concern
EU Least Concern
Relation to
Source European Red List habitat factsheet
European Red List of habitats reports
European Red List of habitats (Excel table)


Open scrub on gypsum-rich substrata growing in dry to semiarid Mediterranean climate, mostly distributed in the central and south-eastern Iberian Peninsula and with small representations in some Mediterranean islands (Sicily and Cyprus). It develops on sedimentary evaporitic bedrocks rich in gypsum (gypsisols in the FAO soil classification), locally called aljezares (from Arabic aljez = gypsum) of Triassic, Oligocene and Miocene ages. Many of the species of this type are linked to this particular edaphic conditions, being called gypsohytes or gypsophilous species. Many of them are narrow endemics of Iberian or even more restricted distribution, particularly among the scrub species, but also some of the annuals. A few of them are also present in North Africa (Helianthemum squamatum, Lepidium subulatum, Ononis tridentata) or in other countries in the Mediterranean Europe (Chaenorhinum exile, Ctenopsis gypsicola). The richness of endemics is higher in the centre and the south of the Iberian Peninsula than in the northern part of the habitat’s range (Ebro Depression), being highest in the southeast (Almeria, Murcia and Alicante). In addition to the gypsophytes, a number of basiphilous scrub plants of wider distribution and ecology occur, such as Rosmarinus officinalis and Thymus species. Remarkably, also among the lichens, one endemic exists: Diplotomma rivas-martinezii. Other lichen species of the habitat have a wide distribution over the Middle East and Central Asian arid territories, suggesting an old connection with these areas during the desiccation of the Mediterranean Sea in the Messinian episode (Upper Miocene). The EU28 area of this type is restricted to parts of peninsular Spain where gypsum outcrops occur under severe dry climatic conditions and tiny representations in Cyprus and Sicily. It occurs also in some areas of North Africa.

The typical structure of this habitat is formed by three main elements: (1) a chamaephytic scrub of low height (5-60 cm) and low cover in a dispersed formation, (2) a hard lichen crust covering the soil in between the shrubs, and (3) an ephemeral therophytic community appearing in rainy springs, populating the space between shrubs in early summer. This state is quite stable and natural succession is slowed down because of the extreme conditions of soil, slope and severe drought. A moderate sheep grazing pressure is compatible with an optimal state for preventing succession towards shrubland (maquis with Juniperus and Quercus coccifera) and perennial grassland (Machrochloa tenacissima, Brachypodium retusum). The appearance of this habitat, humble, dry and open, entails an idea of poverty and aridity largely extended in the mentality of most of the human society. For that reason, very often those gypsum scrubs have been despised and its area used as landfills, for wind turbines, for quarrying gypsum, and other uses, even after the approval of the Habitat Directive by the European Union in which they were declared as a Priority Habitat. In addition to this and despite its importance, many attempts have been made to perform restoration of woodlands, mostly with pines (Pinus halepensis), which have mostly failed due to the severe soil and climate conditions.

Indicators of good quality:

The following characteristics may be considered as indicators of good quality, but these indicators differ in different regions:

• Presence of gypsophytes, particularly endemics, including threatened species

• Scrub of low height and low cover

• High cover of open soil covered by lichen crust

• Low to moderate cover of vascular plant vegetation, particularly chamaephytes

• Low cover of encroaching tall grasses and shrubs

Characteristic species
For full habitat description, please download the habitat factsheet.

Threat status

Synthesis of Red List assessment

The gypsaceous hills in central and eastern Spain constitute the main proportion of this habitat in the EU 28 and EU 28+ and also encompass its highest quality areas. These hills have been traditionally used for grazing by sheep and goats and nowadays are being simply abandoned. Some of them have suffered artificial pine plantations and there are gypsum quarries in a few places and some areas have suffered from urbanisation, but the majority of those areas are are conserved in good conditions. Only the effects of the release of the grazing pressure could, in a medium-long term, lead to an evolution towards tall shrub or forest habitats due to succession. So far there is no danger of severe reduction of this habitat and its threat category is Least Concern but it is recommended to include these habitat into protected areas in order that an apprpriate policy for conservation could be applied. The habitat representations of Sardinia, Sicily and Cyprus should deserve more concern in conservation effort due to their isolation.
Red List Category Red List Criteria
Least Concern -
Red List Category Red List Criteria
Least Concern -

Confidence in the assessment

Red List of habitat categories and criteria descriptions

Pressures and threats

  • Sylviculture, forestry
    • Artificial planting on open ground (non-native trees)
  • Mining, extraction of materials and energy production
    • Open cast mining
  • Transportation and service corridors
    • Paths, tracks, cycling tracks
  • Urbanisation, residential and commercial development
    • Urbanised areas, human habitation

Habitat restoration potential

As it is a scrub accompanied by annual communities in the open gaps, the recovery after severe damage is relatively quick and spontaneous if seed sources are available.

Trends in extent

Average current trend in quantity

Decreasing Decreasing
EU28 EU28+

Trends in quality

Average current trend in quality

Decreasing Decreasing
EU28 EU28+

Conservation and management needs

The best conservation policy for this habitat is “hands off” and maintaining a low sheep grazing pressure. The abandonment of traditional land use has meant the release of sheep grazing and the secondary succession in many areas occupied by this habitat. This entails a degradation of the quality and a retreat of the occupancy of these gypsum scrubs; a moderate disturbance regime, mostly by means of sheep grazing, is necessary to keep this habitat in a stable high quality situation. Control of pine plantations, development of urban areas and gypsum quarrying is also necessary.

List of conservation and management needs

  • Measures related to spatial planning
    • Establish protected areas/sites


For each habitat a distribution map was produced from a wide variety of sources indicating known and potential occurrences of the habitat in 10x10 km grids within Europe. Occurrences in grid cells were given in two classes: actual distribution from relatively reliable sources (surveys, expert knowledge), and potential distribution based on models or less reliable indicators. Please download the fact sheet to see the map.

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)
Cyprus Present 0.01 Stable Stable
Spain mainland Present 1411 Decreasing Decreasing
Sicily Present Unknown Unknown Unknown
EU28 + Present or presence uncertain Current area of habitat (Km2) Recent trend in quantity (last 50 years) Recent trend in quality (last 50 years)

Extent of Occurrence, Area of Occupancy and habitat area

Extent of Occurrence (EOO) (Km2) Area of Occupancy (AOO) Current estimated Total Area Comment
EU28 1219050 791 1416.5 Almost all of this area is concentrated in Spain
EU28+ 791 1416.5 Almost all of this area is concentrated in Spain
AOO = the area occupied by a habitat measured in number of 10x10 km grid cells.
EOO = the area (km2) of the envelope around all occurrences of a habitat (calculated by a minimum convex polygon).

Characteristic species

Not available

Vegetation types

Relation to vegetation types (syntaxa)

Not available

Other classifications

Not available
European Environment Agency (EEA)
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