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Camison A.,University of Salamanca | Miguel R.,University of Salamanca | Marcos J.L.,University of Salamanca | Revilla J.,University of Salamanca | And 5 more authors.
Forest Ecology and Management | Year: 2015

In the Mediterranean region, over the past few centuries human activity has modeled the landscape, leading to forest degradation. However, as in many parts of the European continent since the second half of the twentieth century, the Iberian Peninsula has been subject to a substantial degree of land abandonment that has led to the expansion of important secondary forests. One of the dominant tree species in the transitional forests of mountain areas between the Mediterranean and Euro-Siberian regions of the Iberian Peninsula is the deciduous oak, Quercus pyrenaica Willd. The main objectives of the present work were to study the mode of regeneration and forest dynamics of Q. pyrenaica in several types of stands: young forests, mature and previously perturbed forests, and abandoned Pinus reforestations. With this in mind we established eight plots in the mountain range of the Sierra de Francia-Quilamas, in the west subdivision of the Spanish Central System. We analyzed the age and dbh distributions, regeneration density, and the spatial structure of trees and saplings. Young Q. pyrenaica stands were seen to show episodic recruitment after land abandonment consistent with a 'catastrophic' mode of regeneration. These stands were characterized by unimodal age-cohorts, with tree recruitment dropping drastically as the canopy developed and closed in, except at some study sites where the more shade-tolerant Castanea sativa was found. Older and previously disturbed Q. pyrenaica stands showed bimodal age cohorts, the young ones exhibiting a clumped pattern associated with canopy gaps and/or a lower tree density of the older cohort. In abandoned Pinus reforestations, the recruitment of Q. pyrenaica was also associated with canopy openings. These findings show that Q. pyrenica also undergoes a gap-phase mode of regeneration. An abundant regeneration of Q. pyrenaica could be found at all the stands, guaranteeing the persistence of seedling banks (but a scarcity or lack of saplings) under closed forests, until canopy gaps may allow some Q. pyrenaica individuals to grow and reach the main canopy. © 2015 Elsevier B.V. Source

Raftoyannis Y.,Technological Educational Institute of Lamia | Nocentini S.,University of Florence | Marchi E.,University of Florence | Sainz R.C.,Dip.to Selvicultura y Gestion Forestal | And 7 more authors.
IForest | Year: 2014

Climate change has already increased fire risk in Mediterranean forests. Adaptation options related to forest fires and climate change include measures related to fuel management, fire fighting and infrastructure, as well as public awareness. The importance of each of these measures was evaluated in six Mediterranean countries in a study initiated within the COST Action FP0703 "Expected Climate Change and Options for European Silviculture". A questionnaire survey was used to document the views of foresters and forest scientists. Country differences were observed and adaptation measures related to fire fighting efficiency and public awareness were valued as more important than fuel management. Results were discussed in the light of a critical review of adaptive fire management measures with special reference to European Mediterranean countries. © SISEF. Source

Tome J.,University of Lisbon | Gordo J.,Servicio Territorial de Medio Ambiente | Tome M.,University of Lisbon
Ecological Modelling | Year: 2011

Modelling masting habit, i.e. the spatial synchronized annual variability in fruit production, is a huge task due to two main circumstances: (1) the identification of main ecological factors controlling fruiting processes, and (2) the common departure of fruit data series from the main basic statistical assumptions of normality and independence. Stone pine (Pinus pinea L.) is one of the main species in the Mediterranean basin that is able to grow under hard limiting conditions (sandy soils and extreme continental climate), and typically defined as a masting species. Considering the high economical value associated with edible nut production, the masting habit of stone pine has been a main concern for the forest management of the species. In the present work we have used annual fruit data series from 740 stone pine trees measured during a 13 years period (1996-2008) in order: (a) to verify our main hypothesis pointing out to the existence of a weather control of the fruiting process in limiting environments, rather than resource depletion or endogenous inherent cycles; (b) to identify those site factors, stand attributes and climate events affecting specific traits involved in fruiting process; and (c) to construct a model for predicting spatial and temporal patterns of variability in stone pine cone production at different spatial extents as region, stand and tree. Given the nature of the data, the model has been formulated as zero-inflated log-normal, incorporating random components to carry out with the observed lack of independence. This model attains efficiencies close to 70-80% in predicting temporal and spatial variability at regional scale. Though efficiencies are reduced according to the spatial extent of the model, it leads to unbiased estimates and efficiencies over 35-50% when predicting annual yields at tree or stand scale, respectively. In this sense, the proposed model is a main tool for facilitating decision making in some management aspects such as the quantification of total amount of cones annually supplied to nut industry, design of cone harvest programs or the optimal application of seedling felling. © 2010 Elsevier B.V. Source

Barbadillo Escriva De Romani P.,Avda. Balearic Islands | Garcia-Lopez J.M.,Servicio Territorial de Medio Ambiente | Mateo Sanz G.,University of Valencia | Rodriguez Garcia A.,University of Leon
Flora Montiberica | Year: 2016

31 Taxa with either quotations or remarks, related to their existence within the province of Burgos, are mentioned. 8 out of these aforementioned ones mean a novelty value for the provincial catalogue. Source

Barbadillo Escriva De Romani P.,Avda. Balearic Islands | Garcia-Lopez J.M.,Servicio Territorial de Medio Ambiente | Garcia Valcarce R.M.,University of Leon | Mateo Sanz G.,Jardin Botanico de Valencia | And 4 more authors.
Flora Montiberica | Year: 2014

Additions and revisions to "Atlas de la Flora Silvestre de Burgos", VII. 73 taxa with either quotations or remarks, related to their existence within the province of Burgos, are mentioned. 13 out of these aforementioned ones mean a novelty value for the provincial catalogue. Source

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