<?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%">Alias, S</style></author><author><style face="normal" font="default" size="100%">Bianchi, L</style></author><author><style face="normal" font="default" size="100%">Calamini, G</style></author><author><style face="normal" font="default" size="100%">Gregori, E</style></author><author><style face="normal" font="default" size="100%">Sioni, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Shrub facilitation of Quercus ilex and Quercus pubescens regeneration in a wooded pasture in central Sardinia (Italy)</style></title><secondary-title><style face="normal" font="default" size="100%">iForest - Biogeosciences and Forestry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Overgrazing</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus pubescens</style></keyword><keyword><style  face="normal" font="default" size="100%">Shrub facilitation</style></keyword><keyword><style  face="normal" font="default" size="100%">Tree regeneration</style></keyword><keyword><style  face="normal" font="default" size="100%">Wood pasture management</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">Submitted</style></year></dates><publisher><style face="normal" font="default" size="100%">SISEF - Italian Society of Silviculture and Forest Ecology</style></publisher><pub-location><style face="normal" font="default" size="100%">University of Sassari, v. Sa Terra Mala, I-08100 Nuoro (Italy)</style></pub-location><volume><style face="normal" font="default" size="100%">3</style></volume><pages><style face="normal" font="default" size="100%">16-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">In the woodlands of Sardinia, as in many other areas of the Mediterranean region, grazing of domestic animals is still very common, though often in the absence of any sustainable management logic or technique. The present work analyzes the effects of excessive grazing pressure on a wooded pasture in the municipality of Orgosolo (Nuoro province), emphasizing the effects on the natural regeneration of the oak species (Quercus ilex and Quercus pubescens). This study has revealed the positive effects of the interaction between shrubs and seedlings of tree species. Crataegus monogyna proved to be the most efficient shrub species in favouring the establishment and growth of saplings; Rubus ulmifolius is efficient in the establishing phase but somewhat less so in the following stages. The other shrub species (Prunus spinosa, Genista pichi-sermolliana, Stachys glutinosa) play a lesser facilitating role. Despite the fact that seedlings are found in more than half (56%) of the shrub patches, the average age of the seedlings (14�0.6 yrs) and their small average size (height 24�1.4cm) lead to think that the present grazing pressure is incompatible with any concrete chance of success for their natural regeneration.</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%">Gutiérrez, Álvaro Gómez</style></author><author><style face="normal" font="default" size="100%">Schnabel, Susanne</style></author><author><style face="normal" font="default" size="100%">Contador, Francisco Lavado</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gully erosion, land use and topographical thresholds during the last 60 years in a small rangeland catchment in SW Spain</style></title><secondary-title><style face="normal" font="default" size="100%">Land Degradation &amp; Development</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Gully erosion</style></keyword><keyword><style  face="normal" font="default" size="100%">land use</style></keyword><keyword><style  face="normal" font="default" size="100%">orthophotographs</style></keyword><keyword><style  face="normal" font="default" size="100%">Overgrazing</style></keyword><keyword><style  face="normal" font="default" size="100%">topographical thresholds</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year></dates><publisher><style face="normal" font="default" size="100%">John Wiley &amp; Sons, Ltd.</style></publisher><volume><style face="normal" font="default" size="100%">20</style></volume><pages><style face="normal" font="default" size="100%">535-550</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Gully erosion plays an important role in degradation processes of Mediterranean environments. In this paper aerial orthophotographs were used for (i) analysing the evolution of a valley bottom gully and its relation with land use and vegetation cover, (ii) exploring the role of land use and vegetation cover on the coefficients of the equation S = aA−b (where S is slope at the headcut and A is drainage area), which is based on the topographical threshold concept and is commonly used to predict gully initiation. The study was carried out in a small catchment (99·5 ha) located in the southwest of the Iberian Peninsula. Gullies and headcuts were mapped together with land use and vegetation cover using aerial photographs for the years 1945, 1956, 1989, 1998, 2002 and 2006, which had to be digitized and orthorectified in advance. The results showed an increase of the area affected by gullying from 695 m2 in 1945–1009 m2 in 2006, reaching a maximum of 1560 m2 in 1956. Gullying was closely related with land use, especially with the amount of cultivated areas within the catchment and also with grazing intensity. No clear relationship was found between the evolution of the gullied area and rainfall amounts. Finally, the values of the exponent b obtained for different headcuts and different dates (close to 0·4) were similar to those proposed by other authors for gully erosion caused by Hortonian overland flow in semiarid environments. Copyright © 2009 John Wiley &amp; Sons, Ltd.</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%">Rodriguez, R</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effects on natural regeneration of woodland in a dehesa system grazed by Avilena-Negra Iberica Breed</style></title><secondary-title><style face="normal" font="default" size="100%">Cahiers Options …</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">cattle.</style></keyword><keyword><style  face="normal" font="default" size="100%">dehesa system</style></keyword><keyword><style  face="normal" font="default" size="100%">no transhumance exploitation</style></keyword><keyword><style  face="normal" font="default" size="100%">Overgrazing</style></keyword><keyword><style  face="normal" font="default" size="100%">regeneration woodland</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1999</style></year></dates><pages><style face="normal" font="default" size="100%">257-259</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Effects on concentrated calving against continuous calving and different supplementation levels on cattle in a dehesa system have been studied. In these experimental conditions we considered it necessary to evaluate grazing effectso n natural regeneration of holm oaks (Quercus rotundifoliaa) nd cork oaks (Quercus suber).</style></abstract></record></records></xml>