Human Influences on the Pine and Laurel Forests of the Canary Islands

Abstract

THE effect of human activities on the vegetation mantle of the earth historically has tended to be especially severe on island ecosystems. The Canary Islands, which originally supported substantial stands of both coniferous and broadleaf evergreen forests, offer an instructive, but little-known example of this continuing interaction between man and environment. Located some 100 kilometers off the North African coast at 28?N, the Canary archipelago, structurally an extension of the Atlas Mountains, has been an isolated ecologic system since the Tertiary period. The extravagantly broken volcanic topography has created a remarkable diversity of niches, from sea level to the snow-capped summit of Tenerife (Pico de Teide, elevation 3,715 meters) and from the dripping cloud forests of exposed trade-wind slopes to the desertic lee sides where annual precipitation may be less than 100 millimeters.' Tenerife and Gran Canaria, the largest of the seven islands, have been termed with some reason continents in miniature.