<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Espejo, J M Recio</style></author><author><style face="normal" font="default" size="100%">Faust, D</style></author><author><style face="normal" font="default" size="100%">Granados, M A Nuñez</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The origin of the Sierra de Aracena Hollows in the Sierra Morena, Huelva, Andalucia, Spain</style></title><secondary-title><style face="normal" font="default" size="100%">Geomorphology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">deep weathering</style></keyword><keyword><style  face="normal" font="default" size="100%">hercynian massif</style></keyword><keyword><style  face="normal" font="default" size="100%">hollows macroforms</style></keyword><keyword><style  face="normal" font="default" size="100%">sierra morena</style></keyword><keyword><style  face="normal" font="default" size="100%">Spain</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2002</style></year></dates><volume><style face="normal" font="default" size="100%">45</style></volume><pages><style face="normal" font="default" size="100%">197-209</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Hollows in the Sierra de Aracena, part of western sector of Sierra Morena region (Huelva, Spain), are geoecologically unusual macroforms. They are underlain by deeply weathered bedrock but have eutrophic soils with distinctive vegetation. Paleosols with very dark colours, a predominance of smectites and large amounts of total and free iron occur on the floors on the hollows. An evolutionary model is proposed for the hollows, involving differential weathering during the Mesozoic on plutonic and amphibolitic rocks, alpine tectonic activity followed by Quaternary erosion and exhumation leading to formation of erosional terraces</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ales, R. F.</style></author><author><style face="normal" font="default" size="100%">Martin, Angel</style></author><author><style face="normal" font="default" size="100%">Ortega, Fernando</style></author><author><style face="normal" font="default" size="100%">Ales, E. E.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Recent changes in landscape structure and function in a Mediterranean region of SW Spain (1950–1984)</style></title><secondary-title><style face="normal" font="default" size="100%">Landscape Ecology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">agroecology</style></keyword><keyword><style  face="normal" font="default" size="100%">biological conservation</style></keyword><keyword><style  face="normal" font="default" size="100%">dofiana national park</style></keyword><keyword><style  face="normal" font="default" size="100%">guadalquivir valley</style></keyword><keyword><style  face="normal" font="default" size="100%">sierra morena</style></keyword><keyword><style  face="normal" font="default" size="100%">Spain</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1992</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1992///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/H05121640210820H.pdf</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">3 - 18</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Recent economic development has altered landscape structure and function of a mediterranean region in Southwestern Spain. Intensive agricultural systems have concentrated in the more fertile areas, while margi- nal ones have been abandoned. As a result, landscape structure has changed. Consequences of this structural change on landscape processes are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Joffre, R</style></author><author><style face="normal" font="default" size="100%">Vacher, J</style></author><author><style face="normal" font="default" size="100%">Llanos, C</style></author><author><style face="normal" font="default" size="100%">Long, G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The dehesa: an agrosilvopastoral system of the Mediterranean region with special reference to the Sierra Morena area of Spain</style></title><secondary-title><style face="normal" font="default" size="100%">Agroforestry Systems</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">agrosilvopastoral system</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">effect of trees on soils</style></keyword><keyword><style  face="normal" font="default" size="100%">Mediterranean Region</style></keyword><keyword><style  face="normal" font="default" size="100%">oak trees (Quercus spp.)</style></keyword><keyword><style  face="normal" font="default" size="100%">sierra morena</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1988</style></year></dates><volume><style face="normal" font="default" size="100%">1</style></volume><pages><style face="normal" font="default" size="100%">71-96</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A multidisciplinary team undertook a six-year investigation on the agro-ecological and socio-economic aspects of the dehesa system in the Sierra Norte area, a part of the Sierra Morena of the Sevilla Province, Western Andalusia, Spain. This paper summarizes its findings on the various agro-ecological features of the system and evaluates the system's functional aspects vis-a-vis the trends and developments in land use in the region over the past few centuries. The synergistic effects of tree cover on understorey grassland vegetation is discussed in terms of soil fertility build-up and favourable micro-climatic and hydrological features, and the potential use of this information in future research and development programmes to improve the dehesa system in the Mediterranean region is outlined.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Haeger, J F</style></author><author><style face="normal" font="default" size="100%">González, A R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Les peuplements de fourmis dans la Sierra Morena centrale (Espagne) rapports avec l'exposition et la vegetation</style></title><secondary-title><style face="normal" font="default" size="100%">Insectes Sociaux</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Espagne</style></keyword><keyword><style  face="normal" font="default" size="100%">espèces indicatrices</style></keyword><keyword><style  face="normal" font="default" size="100%">exposition solaire (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">fourmis</style></keyword><keyword><style  face="normal" font="default" size="100%">Maquis</style></keyword><keyword><style  face="normal" font="default" size="100%">pâturage</style></keyword><keyword><style  face="normal" font="default" size="100%">sierra morena</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1982</style></year></dates><volume><style face="normal" font="default" size="100%">29</style></volume><pages><style face="normal" font="default" size="100%">358-368</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Le but de ce travail est d'étudier l'influence d'un facteur biotique (la végétation) et d'un facteur abiotique (l'exposition) sur la distribution des especes de fourmis dans une zone de la Sierra Morena Centrale (Sud de l'Espagne). Pour cela, on a r6alis6 des 6chantil- lonnages stratifi6s dans chaque unit6 de v6g6tation, en soulane et en ombrée. L'analyse des correspondances a permis d'abord de s6parer les espèces trouvées dans les principaux types de v6gdtation de la zone d'étude (pâturage, reboisement de pins et zone inondée le long d'une rivière). Quand on supprime les relevés des endroits inondables, on peut distinguer les espèces indicatrices des zones oú prédominent soit le maquis (&quot;matorral&quot;) soit le pâtturage (&quot;dehesa&quot;), ainsi que celles des zones exposées en soulane ou en ombrée. Dans la zone reboisée, il est impossible de distinguer des espèces indicatrices des associations végétales caractéristiques du milieu, ce qui peut s'interpréter comme une conséquence de l'homogénéisation due aux pratiques culturales.</style></abstract></record></records></xml>