Mediterranean to Atlantic open, dry, acid and neutral grassland

Siliceous low sized grasslands of low density and biomass, formed by small ephemeral annuals presenting the typical eco-morphological traits syndrome of the pioneer initial stages of succession. Vascular plant species have a short life cycle of less than one year, usually starting in autumn/winter with the germination and seedlings establishment, followed by a fast growth in early spring and a flowering and a rapid seed production in late spring to early summer. After seed dispersal, the plants immediately die (agostamiento in Spanish) leaving their offspring in form of dormant seeds lying in the soil seed bank until autumn rainfalls trigger germination and the outbreak of a new generation. The biomass of the vegetative phases of this cycle strongly depends on the rainfall amount during early spring, reaching to have high biomass if abundant precipitations are received in the wet season and remaining practically invisible when drought becomes dominant in spring. In such cases seeds remain dormant in the seed bank until the next germinating period.

Soils are dry, with no gravitational surplus of water and no hydromorphy in their profile. Texture varies from coarse sandy to lime rich and inorganic nutrient content is generally low, with low values of pH. The disturbance regime endured by these grasslands does not include strong nitrification due to artificial fertilization nor soil tilling, keeping soils structured and with low content in nitrogen and phosphate compounds. This habitat almost always occupies small surfaces in mosaic with others, usually shrubby or herbaceous, vegetation types, in the clearings and open spaces between shrubs or other taller perennial herbs or grasses. In the Mediterranean region as well as in other Atlantic areas, the scrub or heathland landscape, resulted from human disturbance, entails such inextricable mosaic between patches of these annual grasslands and the scrub itself that it becomes extremely difficult to disentangle one from the other in the medium to large scale, making it difficult performing separate cartographies. These annual grasslands are considered being the initial stage of succession replacing mature vegetation of mainly Quercus forests in disturbed areas submitted to grazing and fire.

This habitat type is the silicicolous replicate of E1.3c being more widely represented in Temperate and Atlantic Europe as in these areas base poor substrata are more frequent due to the leaching effect on the soils favored by the more abundant summer rainfalls. In spite of its low biomass, this habitat type can reach a high species richness, particularly in Mediterranean countries. The total number of taxa bounded to this habitat type is more than one hundred, most of them with a Mediterranean optimal distribution, with few endemics of restricted area. This habitat, together with the homologous E1.3c of base-rich soils, incorporate the majority of the European annual vascular flora not bound to nitrophilic environments.

These grasslands can represent an appreciable resource for grazing flocks in spring period, when they are exploiting the scrub and heathland areas. They are not a highly valuable pasture in absolute terms, but they increase substantially the values of these scrub areas in spring, when sheep are breeding their lambs; for that reason, these grasslands contribute strategically to satisfy a temporary additional energetic and protein demand of the flocks and are much appreciated by the shepherds.

This habitat type occurs in most of the Temperate and Mediterranean countries of Europe but the highest frequency, quantity and diversity is found in the western Mediterranean area, particularly in the Iberian countries, where there are large areas with siliceous substrata with abundant scrub (matorral, garrigue or phrygana). It is also common in the siliceous territories of North Africa and Middle East.

Indicators of good quality:

·       medium disturbance regime

·       extensive grazing

·       absence of nitrophilous species

·       absence of signs of secondary succession (e.g. encroachment of chamaephytes or shrub species)

Synthesis of Red List assessment

Confidence in the assessment

Pressures and threats