학술논문
Cartografía de los sabinares de Juniperus turbinata Guss. en la reserva de la biosfera de El Hierro (Islas Canarias) mediante teledetección
Document Type
Dissertation/Thesis
Author
Source
TDX (Tesis Doctorals en Xarxa)
Subject
Language
Spanish; Castilian
Abstract
The Juniperus turbinata Guss junipers, most extensive of the Canarian archipelago, are located in the El Hierro, it is the most sub-western island. The orography of the island is abrupt, with the highest summit being Malpaso with 1,501 m. The trade winds have an influence from the northern slope to the southern one. The combination of the trade winds of the NE and the topography of the island produces cloudiness in medium and high levels most days of the year. The genus Juniperus is a protected taxon in European legislation, in the Spanish and in various autonomous communities (Canary Islands and Andalusia). The advances in remote sensing allow to have images of great resolution, making it possible to delimit with more precision the surface of the junipers, increasing the reliability of those inaccessible areas. In addition they are an alternative before the difficulty of the field work. Studies have been carried out on the biodiversity of the junipers on the island of El Hierro, the current state of their populations, their capacity for regeneration, their possible regression and the actions to be taken to promote their conservation. The main objective of this work was the elaboration of the cartography of the Juniperus turbinata Guss., in the island of El Hierro, from GeoEye-1 images, and to determine the surface and density of individuals. As the obtaining of satellite images produces geometric distortions, they are affected by the atmosphere and by the relief, for that reason the geometric and radiometric corrections were made, which due to the characteristics of the island have been quite laborious. Different vegetation indexes were calculated and the results obtained the correction and classification of the existing vegetation covers are presented. Through historical sources it is known that its extension had been greater, but due to anthropic and environmental factors its surface has been considerably reduced. The results of this investigation allowed to know the current extension and density of the juniper according to the type of juniper, being a fundamental information for the management of the reserve.