Forests of the Iberian Peninsula

The woodlands of the Iberian Peninsula are distinct ecosystems on the Iberian Peninsula (Spain and Portugal). Although the various regions are each characterized by distinct vegetation, the borders between these regions are not clearly defined, and there are some similarities across the peninsula.

The flora of the peninsula, because of bio-historical, geographical, geological, and orographic conditions, is among of the richest and most varied of all European floras, rivaled only by such countries as Greece and Italy; it is estimated that the Iberian Peninsula has more than 8,000 distinct species of plants, many of them endemic.

It is now known that the Mediterranean Sea went through great changes in sea level and variations in the relative positions of the continental plates of Europe and Africa. These brought changes of climate and vegetation.

The Iberian Peninsula, located on an important route between Africa and Europe, was enriched by the arrival, following the climate change, of wetland plants, thermophilic plants (those that require a great deal of heat), xerophilic plants (those that require a dry climate), orophilic (sub-alpine) plants, Boreo-alpine plants, and so on, many of which managed to remain, thanks to the diversity of environments that exist in the mountain ranges, and which allowed them to rise in altitude if the climate was too warm, or descend if it became too cold. The geological complexity of the majority of Iberian mountains, especially of the Cordillera Bética, Sistema Ibérico, and Pyrenees, also greatly increased the number of new environments to which it was possible to adapt, resulting in today's wide variety of flora.

The "Eurosiberian" Atlantic zone extends through northern Portugal, the Galician Massif, Cantabrian Mountains and the western and central Pyrenees. It is characterized by a humid climate which is moderated by the influence of the ocean, with somewhat cold winters and the lack of a distinct dry season. The mainland extends to the north of Portugal, the greater part of Galicia, Asturias, Cantabria, the Basque Country, northwest of Navarre, and western Pyrenees. However, its influence in the form of communities or defined species extends inwards, especially in the north and west.

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