Spain's Dry Regions & Mediterranean Forests

Dry Regions of Spain

The dry regions of Spain cover the largest territory of the Iberian Peninsula. This area occupies the two sub-plateaus and the basins of the Guadalquivir and Ebro rivers, in addition to Extremadura, Valencia, southern Catalonia, and the Balearic Islands. In these areas, rainfall ranges between 400 and 800 mm annually. However, other areas are classified as semi-arid, where rainfall is between 200 and 400 mm.

Rainfall Patterns

Semi-arid areas include Almeria, Murcia, parts of the Ebro and Duero depressions, Granada, and Alicante, as well as part of the Canary Islands.

Causes of Aridity

In the Canary Islands, the shortage of rainfall is due to their latitude and the influence of the Azores High. In the south of the peninsula, the Sahara anticyclone plays a role. For the central zone, the low level of rainfall is due to its remoteness from the coast, which causes storms to be significantly weakened by the time they reach the interior.

Plant Adaptations

In the dry and semi-arid Mediterranean forest, species have developed numerous mechanisms to adapt to long dry periods, which alternate with winter frosts. The oak is the most abundant species, but it may be associated with others.

Types of Mediterranean Forest

There are three main types of Mediterranean forest:

Mainland Oak Woodlands

Occurs in the northern and southern sub-plateaus and in the Ebro depression, featuring oaks.

Subhumid Cork Oak Forests

Found in Extremadura and northern Andalusia, characterized by cork oaks.

Coastal & Arid Zone Plants

Occurs along the Mediterranean coast to Gibraltar, combining oak with carob and pine. In more arid areas, palms are also present.

Human Influence & Land Use

Mediterranean forests are among the most altered by human activity. Their potential area is now covered by a variety of land uses, with few areas of forest remaining, interspersed with crops, pastures, industry, and infrastructure.

The Dehesa Agroforestry System

Importantly, oak forests were transformed over the years into a unique agricultural and farming system known as the dehesa.

Coastal & Island Ecosystems

The coastline and the Balearic Islands are also significantly influenced by the Mediterranean climate, impacting vegetation. This coastal strip is very diverse, featuring rocky and sandy areas. There are significant differences between the Catalan coast, the Balearic Islands, and the Valencia-Murcia-Almeria region.

On the Catalan coast, Mediterranean oaks are found in areas covered by maquis (a type of shrubland that can reach two meters and includes species like palms). The Balearic Islands and the Valencia-Murcia-Almeria region show different characteristics. The latter features predominantly drier vegetation adapted to semi-arid conditions.