Covering Cocelhos of Vila Real de Santo António, Tavira, Olhão, Faro and Loulé, we have the Natural Park of Ria Formosa
Natural Park of Ria Formosa - Dune Vegetation
The conditions of formation and dynamics of geomorphological dunes show that these structures are unstable. The proximity of the sea acts as a highly selective factor in the establishment and growth of vegetation. Apparently simple, this medium is actually quite complex and precarious. It is no coincidence that on the side facing the sea, is seen as very poor flora: the coastal plants are subject to strong winds laden with salt particles, the luminosity, the temperature ranges that go from the scorching sun of summer to the bitter cold winter. This causes considerable transpiration in the plant, which, combined with high permeability soil dune, leaving quickly infiltrate the water that falls on it, irremediably condemned to a hostile xerophytic, ie an environment where conditions prevail dryness. To this we must resist, to survive. And indeed psammophytes plants that live in the sand near the Beaches, because they have developed adaptations to survive more or less great as to prevent excessive losses above the water. However, not only against drying the plant to fight, she also has to deal with the burial, when strong winds or constant from the sea, pushing the sand from the beach inland.
A first dune facing us, or call anteduna dune age, relatively low and highly unstable, show, the part facing the sea and near the upper limit of the tides, an association of Cakile maritima Scop. and Salsola kali L.; have more to the top, Elymus farctus (Viv.) RUNEMARCK EX MELDERIS and sometimes paralias Euphorbia L. and E. Peplis L. The vegetation in this narrow band is very sparse and the wind moves easily with sand, which drags the interior, despite the short distance implemented at the new location where they are deposited is more welcoming, less severely suffer the effects of wind and the breeze gets there less salt. Conditions are created, if not favorable, at least more favorable for the establishment of other plants, in turn, these will, in various ways, retain more sand. Along with Elymus farctus now comes another great edifying of dunes and pioneer in its colonization: Ammophila arenaria (L.) LINK, commonly called chargeback. Accompany it even Euphorbia paralias and can already see here in the lambs from the beach, Otanthus maritimus (L.) Hoffmanns. & LINK. So the dune grows, the floristic composition rich and varied.
Reached the top can be found Calystegia soldanella (L.) R. BR., Whose seeds, very heavy, they penetrate easily, thus offsetting the adverse conditions for the survival of the species, Lotus creticus L., Eryngium maritimum L., L. Crucianella maiítima Pancratium maritimum L., together with Ammophila arenaria which, incidentally, grows all over the side, stands more or less dense, as the area where he settled.
On the inside of the dune and interdune following it, on land already finally determined, along with some of the other species already mentioned are in addition to the list of psammophytes: Helichrysum italicum (Roth) G. DON FIL., Pseudorlaya pumila (L.) GRANDE, Thymus carnosus Boiss., Armeria pungens (Link) Hoffmanns. & LINK, Artemisia campestris L. subsp. maritima ARCANGELI, Anthemis maritima L., Corynephorus canescens (L.), Beauv., Linaria lamarckii Rouy and L. pedunculata (L.) Chaz., Reichard Cadiz (Willk.) COUT. Silene nicaeensis or ALL., that to mention only the most abundant and conspicuous. It will not be emphasized enough that Thymus carnosus is a Portuguese endemic, that is, this plant is only in Portugal and here only in the Alentejo and Algarve. It's that little green tuft of dark-sized amoitado that, more than any other plant of the dunes, where crushed leaves around an intense and pleasant perfume somewhat similar to lavender.
The set of interdune sands provide good conditions for the growth of prostrate, the root system rather short, generally smaller leaves, which spread in large round spots. Examples Paronychia argentea Lam., Ononis variegata L., Medicago littoralis Loisel. Polygonum maritimum L. or Hypecoum procumbens L., another species that occurs only in the Algarve. No limit on the understory should be highlighted monelli Anagallis L., prostrate beautiful flowers bright blue, sparta Linaria (L.) Willd., Scrophularia frutescens L., Cleome violacea L. Corrigiola littoralis L. Aetheorhiza bulbous (L .) CASS. and Pycnocomon rutifolium (VAHL) Hoffmanns. & LINK, this also confined to the Algarve and a few more places on the Mediterranean Europe.