Please use this identifier to cite or link to this item: http://hdl.handle.net/20.500.12136/1455
Item metadata
Title: Evolution of the vegetation, during the Holocene in the Sierra de Urbión and Neila (Sistema Ibérico, Spain)
Authors: Gil García, María José
Ruiz Zapata, María Blanca
Vegas Salamanca, Juana
Pérez-González, Alfredo
Issue Date: 2014
Publisher: International Union for Prehistoric and Protohistoric Sciences (IUPPS)
Citation: XVII World UISPP Congress, 2014, p. 832
Abstract: Pollen data from two lacustrine sequences are presented: LHN-H (Soria) and QS2-H (Burgos), located in the Iberian system in order to establish the behavior of the vegetation during the Holocene, as well as to detect some of the most significant events of this period from the climatic point of view (8.200, 2,800 and 4,100 cal BP). The formation of both sequences is related to the withdrawal of the ice of the last glacial period, due to overpasses or proglaciar character, respectively. In both cases, it’s one of the most sensitive files in the registry of climatic events. Radiometric dating,have identified the power of sediment accumulated during the Holocene. For the extraction of pollen grains, the samples were attacked chemically with acids and alkalis; then the residue, was concentrated through the use of dense liquor of Thoulet. The graphical representation of the data was conducted with the software package TILIA ®, expressing the relative percentages of all taxa identified in each of the samples, as well as the relationship between all of the no tree, and arboreal pollens as an expression of the structure of the vegetation. In order to facilitate the reading of data has been built a synthetic diagram, based on the selection of taxa and grouping of taxa according to ecological demands, most significant, from the climatic point of view. The vegetation composition defines the installation conditions of warm-humid are characterized by the development of the deciduous forests, consisting basically of Betula and Corylus and to a lesser extent by Quercus type deciduous and Fagus, among others. The development of perennial forest (Quercus type evergreen), takes place is more late, and uncompetitive rates. Climatic events, as mentioned above, are defined through development of the taxa and xeric and subcontinental steppic grasslands, fundamentally Poaceae and Artemisia (8,200), by the increase of Cupressaceae (4,100) or both (2,800), as well as the general loss of the rate of moisture, which leads to the reverse of the deciduous forest and the increase of the mediterranean forest and Ericaceae. In this context of high mountain is very dampened anthropic activity, centered primarily in the increase of nitrophile plants. It is important to point out how the development the forest mass, which characterizes the entire Holocene, presents some peculiarities, for each profile, marked by the altitude and orientation of each of the deposits. The most relevant data is summarized in: 1- Identification both of the Younger Dryas, through the development of the taxa and sub-continental steppic grasslands and xeric. 2- Characterization of the events of the 8,200, 4,100 and 2,800, through the expansion of Cupressaceae and to a lesser extent of the taxa xeric-and sub-continental steppic grasslands. 3- Pinus, next to Betula and Corylus, defined the majority composition of the forest, as a response to the installation of temperate conditions-wet. 4-The behavior of the vegetation, to roof of both sequences is very similar. After a major pine forest, expands Ericaceae, and later again pine forest.
URI: http://hdl.handle.net/20.500.12136/1455
Type: Presentation
Other
Appears in Collections:Congresos, encuentros científicos y estancias de investigación



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.