Microenvironmental Studies in the Laurel Forest of the Canary Islands

Abstract

The Canarian laurel forest is largely restricted to the semi-humid middle elevations of the mountainous western islands, especially to windward slopes. Several ecological subtypes and degradational stages of laurel forest and heath woodland or shrubland are distinguished. The laurel forest is an impoverished relict of mixed oak-laurel forest deriving from the early Neogene. This paper outlines a series of microenvironmental studies designed to answer the question: how can the laurel forest survive in a mediter- ranean-type climate with five to six arid summer months, especially when experiencing heavy human impact? Microenvironmental data were collected during short periods in all seasons from selected field stations. Soil studies were also undertaken. From these data the great microenvironmental contrasts between dense forest sites, degraded successional types, and open terrain clearly emerge. It follows that continued forest destruction will further adversely affect the hydrological regime, pattern of soil erosion, and ground-water reserves, as well as island aesthetics. This will have a continuing deleterious effect on the lowland coastal belt, scene of rapid growth in tourism, banana plantations, and other vital economic activities. A special system of highland- lowland interactions is described and the need for laurel forest belt conservation is expressed as a basis for economic and social stability.