Forest evolution in the Pyrenean grazed mountains

Abstract

The Pyrenees, the Ebro valley and the Montes Ibéricos are mainly Mediterranean and varied. They offered large opportunity fOI plap.t and animal evolution for millions of years prior to the advent of shepherding Man. The mountain turf with its dynamics is protected by woods under steppic conditions and climatic stress. Juníperos, Pinus, Quereus, Buxus and Arctostaphylos are the maio \\, lody genera in these open, grazed steppic forests bordering the Mediterranean regian. Loca11y, in mountains the continentality OI oceanity of the climate is increased by air circulation. Gregarious animals destroy the forest and may favaur desertification, a climatic stress in the top soil that is counteracted by the shade of shrubs, and also by maoy cultural mechanisms linked to "pastoralism". Plant and animal conservation now mainIy depeods 00 the correct use of our ecosystems; especially the preservation of the Mediterranean flora and vegetation will be difficult un1ess domestic animals managed by educated humans are fully integrated in the ecosystem.