comment object diagram represents the ideal profile of the vegetation in the Canaries. At first we discuss the natural landscape (mediation of the action are arthropods), then analyze the effects it has had human intervention, mainly in the historical period (from the S. XV) and what is the current territory.
VEGETATION I. NATURAL
The distribution of natural vegetation and associated fauna, reflects like no other element of the natural environment the effect of front (windward-leeward opposition) in relation to the dominant wind regime (trade winds) and the effect produced by hitting the relief of the islands (green vertical division): Costa and floor basement, sharecropping and summit.
Low-lying islands (Lanzarote and Fuerteventura) have the lowest floor and drought tolerant plant species adapted to aridity mesophilic.
middle islands (Gran Canaria, La Gomera and El Hierro), the middle ground floor (pine, including laurel).
The high islands (Tenerife and La Palma) where is the top floor, with high mountain vegetation.
I.1.--
Coastal Communities coastal rocks or sand.
-under 100 m altitude.
-halophilic communities, sand dune and salt.
-severe environmental conditions: soil salinity, moisture, strong sunlight and wind exposure.
-sea lettuce, sea thyme, salt, sea grape ...
I.2.-Tabaibal-cardonal or basement floor
-xeric scrub species occupied the coastal areas
warm desert climate.
-precipitation below 100-200 mm annually.
-average temperature of 22 º C. Could
-lee reach the 400 m elevation.
-dominant species have tough leaves, small, thorny ...
adapted to aridity and the drying effects of wind. Tabaiba
-sweet, bitter tabaiba, cactus, candle plant, gorse ...
-palms, Tarahal.
I.3.-forests and thickets thermophilic
-on-cactus spurge laurel and to the north and the pine forest in the south.
-precipitation: 200 to 500 mm.
-annual average temperature between 19 º and 22 º C.
-juniper, palm or palm, dragon tree, wild olive, blackwood, mastic and mastic, faya,
heather and Mocan (at altitudes above) scrub jara, tabaiba bitter).
I.4.-Monteverde
Three subtypes: the laurel, the myrtle and heather moorland. Direct influence of the sea of \u200b\u200bclouds
"rainfall: 600-1000 mm.
-average temperature: 18 º -22 º C.
-laurel, Viñátigo, white wood, helchos (laurel), faya, acebiños, Heather
(armband, less demanding in humidity, is better suited to the wind).
I.5.-Pinar, from 500-600 m (south) and 1200-1500 m (north) to 2000 m above sea
clouds.
-Canary Island pine, heather and undergrowth faya (low area north-), rock rose and thyme
(south); undergrowth of gorse and broom (upper zone).
I.6.-mountain scrubland
Above 2000 m only in Tenerife and La Palma is winter snowfall, extreme temperatures and rainfall
weak. Scrubland
legumes: Teide broom, broom, Teide violet, red
tajinaste.
tree: cedar (single).
II .- THE INDUCED CHANGES IN THE NATURAL VEGETATION OF HUMAN ACTIVITY.
activities associated with human settlement, especially the agricultural and livestock
have altered the natural vegetation. Only since the second half of the twentieth century
has added significantly
pressure produced by the construction of buildings and transport infrastructure. Epoca
Hispanic: degradation of forests for cattle grazing thermophilic
extensive.
European Conquest: intensive agriculture, especially the cultivation of sugar cane
(XV century and especially XVI), and the vineyard in the seventeenth yXVIII.
Decrease of the forest, the indirect effect was reduced
surface and groundwater level (water table) and an intensification of
surface erosion.
late nineteenth century: the introduction of intensive agriculture export oriented
.
Since the sixties of the twentieth century: the abandonment of traditional agricultural practices
. Successful reforestation policy
supported by public institutions.
III .- CURRENT VEGETATION Results
combination of natural ecological conditions and changes induced by human activity. Lanzarote and Fuerteventura
: disappearance of forests and xeric material domain. Coastal settlements have fundamentally altered coastal communities, especially the salt marshes.
El Hierro : cactus-spurge, juniper, meadow, pine, laurel pockets.
La Palma : laurel forest, heath myrtle, pine, retamar.
La Gomera : thermophilous forests, juniper, tabaibales, palm, laurel (cedar). Tenerife
: all floors of natural vegetation: cactus-spurge, laurel, laurel pockets, heath myrtle (north), spurge and pine, scrub mountain (1900).
Gran Canaria island that has suffered human action. Thermophilous scrubland widespread, occupied cliffs funds towards palm. Monteverde and pine.
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