-The whole island of Tenerife is built up by volcanic rock. The different rock types developed due to different chemistry of the lava (acidic, intermediate, mafic), and different mechanisms of how the lava comes from the magma chamber to the surface. The latter can happen as a lavaflow, which forms solid rocks with little porosity, or as an explosive gaseous eruption which forms light and porous rocks.
Up to 1000m above sea level the vegetation of the northern exposure of Tenerife is dominated by agricultural land use. Above this altitude Pinus Canariensis can be found. This Pine Forest (Corona Forestal) has been planted by the order of the government of Franco in the year 1950 in order to capture the moisture of the clouds and prevent soil erosion. Before 1950 all the Pine Forest was cut for building economic purpose. Between 500m and 1500m.a.s.l. the Laurisilva Tree can be found. Reaching an altitude of 2000m and above Vegetation increasingly adapts to the special environmental conditions like strong winds, lack of water, lack of soils, high amplitudes of temperature change between day and night, summer and winter.
The present landscape is the result of the historical evolution of this previous factors. Each eruption was followed by a phase of erosion and finally many layers of various rock types were being deposited one above the other. As the different layers are variously susceptible to erosion the landscape we can find today evolved. Further special volcanic landforms are a caldera (radial subsidence of rock) and dykes, which are chimneys of magma rising through already deposited volcanic rock and solidify there.
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