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Submitted by Margarida Galamba (galamba@isa.utl.pt) on 2019-01-08T09:48:01Z No. of bitstreams: 1 REP-CEABN-Artigo_Publicado_Versao_Final-1.pdf: 8990333 bytes, checksum: 68e1de8fb30018aba2832ea0bec9df77 (MD5) Made available in DSpace on 2019-01-08T09:48:01Z (GMT). No. of bitstreams: 1 REP-CEABN-Artigo_Publicado_Versao_Final-1.pdf: 8990333 bytes, checksum: 68e1de8fb30018aba2832ea0bec9df77 (MD5) Previous issue date: 2018-12 info:eu-repo/semantics/publishedVersion

Os técnicos florestais são um dos principais intervenientes no território rural. Os incêndios são a maior ameaça aos espaços florestais portugueses e são maioritariamente um problema social. Com o objetivo de perceber se as competências fornecidas nos diversos cursos universitários da área florestal respondem às diversas solicitações laborais destes profissionais e aos desafios do séc. XXI, realizou-se um levantamento das necessidades formativas dos técnicos, confrontando-as com as diferentes atividades profissionais e a sua formação universitária ao nível da licenciatura e mestrado. A metodologia utilizada incluiu a análise de conteúdos das licenciaturas e mestrados na área das ciências florestais e um questionário enviado por correio eletrónico aos 220 técnicos que trabalham nos Gabinetes Técnico Florestal em Portugal. A taxa de resposta foi de 71%. Desta análise verificou-se que existem diversas novas funções ligadas principalmente às componentes sociais como por exemplo na área da educação ambiental e sensibilização. Assim concluiu-se que as maiores discrepâncias entre o que é importante para o desempenho profissional e a preparação dos técnicos, encontram-se maioritariamente na dimensão humana da gestão dos recursos florestais, nomeadamente na integração da componente social da perceção do risco por parte da população na gestão. Esta componente social reflete-se nas competências ligadas à comunicação com diferentes públicos (competências gerais) e as que estão ligadas às competências sociais e relacionais como gestão de conflitos, dinâmica de grupos e a componente pedagógica info:eu-repo/semantics/publishedVersion

Knowing the increasing trends in natural disasters and losses, it is imperative to take action on disaster risks to improve resilience of European societies to natural hazards. The main goal, therefore, of the ENHANCE project is to develop and analyse innovative ways to manage natural hazard risks. The key is to develop new multi-sectoral partnerships (MSPs) that aim at reducing or redistributing risk, and increase resilience of societies info:eu-repo/semantics/publishedVersion

Knowing the increasing trends in natural disasters and losses, it is imperative to take action on disaster risks to improve resilience of European societies to natural hazards. The main goal, therefore, of the ENHANCE project is to develop and analyse innovative ways to manage natural hazard risks. Key is to develop new multi-sector partnerships (MSPs) that aim at reducing or redistributing risk, and increase resilience of societies. For several reasons, comprehensive and accurate risk information is important for MSPs and for policy-making in general. First, a better understanding of natural hazard risk is important for preventing excessive socio-eco-nomic stress at levels from local to national to international, and in order to plan for reducing risk from extreme events in the future. For example, measures that reduce risk (e.g. levees to prevent flooding) require a certain design level or elevation, which can be derived from historical water level data or hydrological simulation models. Second, post-disaster information on the losses from a natural hazard event is important, in order to prepare (emergency) aid to the region. In addition, accurate post-event loss information is needed to estimate whether financial support is needed in terms of compensation or new investments to recover the area and develop the economy back to its original state info:eu-repo/semantics/publishedVersion

This study investigates the relationship between crop yield anomalies of five major crops and meteorological indices on the pan-European scale. The crop yield data were obtained from Eurostat for the EU administrative Regions (NUTS). The meteorological indices (Standardized Precipitation Index, SPI, and Standardized Precipitation and Evaporation Index, SPEI) were derived from the WATCH Forcing Data for the administrative regions. Linear regression and the moving average were applied to de-trend the crop yield data. Pearson correlation analyses was carried out to explore the relationship between crop yield anomalies and SPI and SPEI. This study built upon an investigation on the relationship between crop yield losses and drought in Portugal.

Neste artigo apresenta-se o caso estudo do Douro e Alto Trás-os-Montes com o objectivo de analisar as alterações espaciotemporais do uso do solo no intervalo de tempo de 1970 a 2007 e a sua correlação com ocorrências de incêndios. Para tal, recorreu-se à cartografia do Inventário Florestal Nacional (1965-78), às Cartas de Ocupação do Solo de 1990 e 2007 e ao levantamento de áreas ardidas de 1975 a 2006, para a criação de várias matrizes de transição com as quais se caracterizaram e analisaram os padrões temporais das dinâmicas de uso do solo. Verificou-se que a paisagem evoluiu de acordo com os factores sociais, muito influenciado pelo êxodo rural. Desta forma, propiciou-se um aumento da classe dos Matos, a par com o decréscimo das classes de agricultura. Quando o sistema interagiu com o fogo, verificou-se a grande sensibilidade do Pinheiro bravo e o aumento da classe de Matos. Esta abordagem mostrou-se importante na medida em que se consegue perceber a evolução da paisagem sob a influência do fogo e sem a presença deste. Tal análise permite agir de forma mais pertinente na gestão da paisagem e servir como uma ferramenta útil ao estabelecimento de novas políticas florestais info:eu-repo/semantics/publishedVersion

A engenharia natural, desenvolvida na Europa central depois da segunda guerra mundial e na Europa mediterrânica nos últimos vinte anos, tem-se recentemente desenvolvido em Portugal com grandes potencialidades de expansão. Para a estabilização e a consolidação das encostas a engenharia natural utiliza árvores e arbustos autóctones com boa capacidade de propagação vegetativa. Uma das características essenciais destas espécies, quer se empreguem como estacas ou plantas inteiras, é a possibilidade de enterrar o seu caule, em cerca de um metro, sem que este facto comprometa a sua viabilidade. Neste artigo seleciona-se uma lista de espécies da flora continental portuguesa com base no conhecimento prático adquirido e nas publicações técnico-científicas de Portugal, da Europa central e centro-meridional. São posteriormente definidos grupos de espécies da flora portuguesa que podem ser consideradas como (i) adequadas para aplicação em obras de engenharia natural em Portugal e (ii) provavelmente adequadas, carecendo de um maior conhecimento através da realização de trabalhos de investigação. Sobre estas últimas prevê-se continuar o seu estudo através de um programa de ensaios para avaliação das suas características biotécnicas. Soil bioengineering was developed in central Europe after World War II and in Mediterranean Europe in the last twenty years; soil bioengineering has been recently applied also in Portugal suggesting its potential future development. Soil bioengineering, to consolidate and stabilize sliding down slopes, uses indigenous trees and shrubs with good vegetative propagation. A key feature of these species, employed as cuttings or as whole plants, is to not get damaged when their stems are buried in the ground about one meter. In this article is selected, from Mainland Portugal flora, a list of plant species, starting from scientific literature of Portugal, Central Europe and Central and Southern Europe, and using practical knowledge developed in Southern Italy. Afterwards groups of species are defined as (i) appropriate for soil bioengineering works to do in Portugal and (ii) probably adequate, requiring further researches to improve the knowledge about their feature. Tests are planned to assess the biotechnical features of this second group. Le génie biologique, développé en Europe centrale après la Seconde Guerre mondiale et dans l'Europe méditerranéenne au cours des vingt dernières années, a été récemment développée au Portugal et on peut imaginer sa grande capacité potentielle d'expansion. Le génie biologique utilise des arbres et arbustes autochtones, avec une bonne capacité de multiplication végétative, pour la stabilisation et la consolidation des pentes. Une caractéristique clé de ces espèces, employées sous forme de boutures ou de plantes entières, est la possibilité d'enterrer leurs tiges, environ un mètre, sans que cela menace leur viabilité. Dans cet article, on a sélectionnée une liste des espèces végétales de la flore du Portugal continental, en fonction de la littérature scientifique du Portugal, du Europe centrale et du Europe centre-méridionale, et de l'acquis des connaissances pratiques. Ensuite on a définis des groupes d'espèces de la flore portugaise qui peuvent être considérées comme (i) appropriées pour les travaux de génie biologique au Portugal et (ii) probablement appropriées, mais que nécessitent plus de recherches pour une meilleure connaissance. Il est prévu de poursuivre l'étude de ce second groupe d'espèces à travers un programme de tests pour mieux évaluer leurs caractéristiques biotechnologiques.

Com base nas parcelas do Inventário Florestal da Tapada da Nogueira, no concelho de Mogadouro, para elaboração do seu Plano de Gestão Florestal, procedeu-se à análise de povoamentos mistos de Quercus pyrenaica e Q. rotundifolia, as duas espécies mais abundantes nesta área e que aí constituem povoamentos de proporções relativas variadas. Os resultados das medições efetuadas apontam para uma predominância de pequenas dimensões de diâmetros (tanto no carvalho como na azinheira), sendo a classe de 10cm de diâmetro à altura do peito (Dap) a mais frequente. São muito raros, sobretudo no carvalho negral, indivíduos com um Dap superior à classe de 20cm, pelo que a área basal do povoamento se apresenta baixa quando comparada com valores de referência da ordem dos 20m²/ha apontados por CARVALHO (2005). Modelos flexíveis de organização do espaço, em que a unidade poderá ser um indivíduo, um bosquete, ou um povoamento de maior dimensão, permitem que se possa prever uma multiplicidade de combinações interessantes na composição e no regime. A estes modelos de silvicultura pensados para a produção de madeira de carvalho podem associar-se outros usos de produção não lenhosa, como por exemplo a da caça aos veados, neste caso possibilitada pelo espaço murado da Tapada. Based on the Forest Inventory plots of Tapada da Nogueira, located in Bragança region, the analysis of mixed stands of Quercus pyrenaica and Q. rotundifolia was performed. In this zone, these two most abundant species have variable area stands. The measurements' results indicate a predominance of small diameters (in both species), the class of 10cm diameter at breast height (dbh) exhibiting the larger frequency. Especially in Quercus pyrenaica stands there are very few individuals with a Dbh higher than the class of 20cm, so the basal area of the stand seems low when compared with the 20m²/ha values presented by CARVALHO (2005). Flexible models of space organization, in which the unit may either be an individual or a larger stand, allow the prediction of a variety of interesting combinations of composition and regime. These models aiming forestry timber production may be associated with other uses of non-wood production such as deer hunting, in this case made possible by the walled area of the Tapada. Utilisant les donnés des placettes de l'Inventaire Forestier de Tapada da Nogueira, dans la municipalité de Mogadouro (région de Bragança), on a procédé à l'analyse des peuplements mixtes de Quercus pyrenaica et Q. rotundifolia. Ces deux espèces sont les plus abondantes dans ce domaine où il y a des peuplements de proportions relatives variées. Les résultats des mesures présentent une prédominance de petits diamètres (dans les deux peuplements), où la classe de 10 cm de diamètre à hauteur de poitrine (Dhp) est la plus fréquente. Surtout dans les peuplements de Quercus pyrenaica, les individus avec un Dhp supérieur à la classe de 20cm sont très rares, donc la surface terrière du peuplement est baisse par rapport aux valeurs de référence de l'ordre de 20m²/ha soulignés par CARVALHO (2005). Dans des modèles flexibles d'organisation de l'espace, l'unité peut être un individu, un bosquet, ou un plus grand peuplement, ce qui permettra une variété de combinaisons intéressantes dans la composition et le régime. On peut associer à ces modèles de sylviculture pour la production de bois de chêne d'autres utilisations telles que la chasse au cerf, dans ce cas rendue possible par la zone murée de Tapada.

Wildfires are an increasingly common disturbance influencing wood recruitment to streams, and thereby affecting their physical and biological condition. Mediterranean countries such as Portugal, where more than 25% of the land area has burned since 1990, are ideal areas to study impacts of wildfire effects on streams. We evaluated the physical structure of 2206 downed wood pieces (DWP) across 27 first- to third-order streams in central Portugal, all of which had experienced recent wildfires. The streams flowed through monospecific upland forests of Eucalyptus, Maritime pines, or Cork oaks and were fringed by a mixture of riparian tree species. DWP structure differed between tree types and between burned and unburned pieces. Post-fire timber-production forests (Maritime pines and Eucalyptus) contributed a higher quantity of thinner, longer and straighter DWP to streams than Cork oak stands. Pieces from Maritime pines had more rootwads and branches than DWP from the other tree types. Pieces from Cork oak and riparian species generally had a bent form, were shorter and had no rootwads. Burned DWP in streams were often from riparian trees. Relative to unburned DWP, the burned DWP occurred more frequently, were larger and straighter, had branches less often, and were more decayed. With more complex branches, rootwads, and a larger diameter, inputs from burned Maritime pine forests are more likely to change stream hydraulics and habitat complexity, relative to inputs from Eucalyptus forests with their simpler structure. This study shows that, less than a decade after wildfires, structure of downed wood in and near streams is strongly influenced by wildfire, but also still reflects intrinsic species characteristics and respective silviculture practices, even after the effects of fire have been accounted for. Under an anticipated shift in landscape cover with higher shrubland proportions and more mixing of Maritime pine and Eucalyptus forests, our results suggest that instream large wood will become scarcer and more structurally homogeneous.

Para a avaliação da diversidade de espécies arbóreas dos povoamentos florestais recorreu-se à quantificação da percentagem da área basal das espécies florestais que compõem as parcelas de amostragem dos Inventários Florestais Nacionais (IFN) de 1995 e 2005. A análise foi realizada ao nível das unidades estabelecidas pelas regiões PROF (Planos Regionais de Ordenamento Florestal) para as quais se verificou através do teste do qui-quadrado se, entre os anos de 1995 e 2005, tinham ocorrido alterações significativas relativamente à distribuição do número de espécies de árvores por parcela de amostragem. Para as oito regiões que apresentaram alterações significativas descreve-se a constituição da sua floresta e caracteriza-se a alteração da diversidade verificada através do cálculo das séries de Hill para 1995 e 2005. Percentage of basal area was used to evaluate tree species diversity in forest stands from 1995 and 2005 National Forest Inventories sample plots. The analysis was carried out at the PROF region level (Forest Management Regional Plans) and statistical Chi-square test was performed to verify if the changes occurred between 1995 and 2005 in the distribution of the number of tree species per sample plot were significant. Eight PROF regions show significant changes. For each of those regions, we illustrate forest composition and the diversity changes are outlined by the evaluation of Hill series for 1995 and 2005. Pour évaluer la diversité des espèces d'arbres des peuplements forestiers on a utilisé le pourcentage de la surface terrière des arbres des placettes d'échantillonnage des Inventaires Forestiers Nationaux (IFN) de 1995 et de 2005. L'étude a été achevée au niveau des régions PROF (Plans Régionaux d'Aménagement Forestier) où nous avons vérifié, utilisant le test Chi carré, si la différence de distribution du nombre d'espèces d'arbres par placette d'échantillonnage, entre 1995 et 2005, était statistiquement significative. Finalement, pour les huit régions qui se sont présentées significatives, nous décrivons la constitution des forêts et les série de Hill pour 1995 et 2005.

Com este trabalho procurou-se quantificar a Produção Primária Líquida (PPL) de povoamentos puros e mistos de Pinus pinaster e de Quercus pyrenaica. A quantificação baseou-se em parcelas de amostragem do último Inventário Florestal Nacional (IFN) localizadas exclusivamente no distrito de Vila Real. Deste trabalho resultou, pela primeira vez, a avaliação de valores de PPL, logo a possibilidade de quantificar a capacidade que estes ecossistemas têm em fixar carbono. Procedeu-se à comparação entre a performance dos povoamentos puros e mistos. Os resultados obtidos apontam para uma maior potencialidade produtiva dos povoamentos mistos, comparativamente aos povoamentos puros, ainda que não estatisticamente significativa. With this study we quantified Net Primary Production (NPP) of Pinus pinaster and Quercus pyrenaica pure and mixed stands. This evaluation was based on sampling plots from the last National Forest Inventory and is exclusively located in the district of Vila Real. Results from this study allowed the first NPP figures for these kind of forest stands, and thus the quantification of these ecosystems potential for sequestering carbon. Pure and mixed stands NPP figures were compared. The results pointed to a greater production potential of mixed stands, though not statistically significant. Cette étude visait à quantifier la production primaire nette (PPL) des peuplements purs et mixtes de Pinus pinaster et Quercus pyrenaica. La quantification est basée sur les placettes d'échantillonnage du dernier Inventaire Forestier National et exclusivement situées dans le district de Vila Real. Le résultat de ce travail a permis d'établir, pour la première fois, les valeurs d'évaluation de PPL, et donc de quantifier la capacité de ces écosystèmes à fixer le carbone. Les performances des peuplements purs et mixtes ont été comparées. Les résultats indiquent une plus grande capacité de production des peuplements mixtes par rapport aux purs, mais non statistiquement significative.

Submitted by Margarida Galamba (galamba@isa.utl.pt) on 2012-04-19T09:42:53Z No. of bitstreams: 1 REP-F.Rego-Silva-2.pdf: 407697 bytes, checksum: 95fe891f6cfa78bb364c2744ca192132 (MD5) Made available in DSpace on 2012-04-19T09:42:53Z (GMT). No. of bitstreams: 1 REP-F.Rego-Silva-2.pdf: 407697 bytes, checksum: 95fe891f6cfa78bb364c2744ca192132 (MD5) Previous issue date: 2010

With this study we quantified Net Primary Production (NPP) of Pinus pinaster and Quercus pyrenaica pure and mixed stands. This evaluation was based on sampling plots from the last National Forest Inventory and is exclusively located in the district of Vila Real. Results from this study allowed the first NPP figures for these kind of forest stands, and thus the quantification of these ecosystems potential for sequestering carbon. Pure and mixed stands NPP figures were compared. The results pointed to a greater production potential of mixed stands, though not statistically significant-------------------------------------------------------Com este trabalho procurou-se quantificar a Produção Primária Líquida (PPL) de povoamentos puros e mistos de Pinus pinaster e de Quercus pyrenaica. A quantificação baseou-se em parcelas de amostragem do último Inventário Florestal Nacional (IFN) localizadas exclusivamente no distrito de Vila Real. Deste trabalho resultou, pela primeira vez, a avaliação de valores de PPL, logo a possibilidade de quantificar a capacidade que estes ecossistemas têm em fixar carbono. Procedeu-se à comparação entre a performance dos povoamentos puros e mistos. Os resultados obtidos apontam para uma maior potencialidade produtiva dos povoamentos mistos, comparativamente aos povoamentos puros, ainda que não estatisticamente significativa

Not all wildfire ignitions result in burned areas of a similar size. The aim of this study was to explore whether there was a size-dependent pattern (in terms of resulting burned area) of fire ignitions in Portugal. For that purpose we characterised 71,618 fire ignitions occurring in the country in the period 2001–2003, in terms of population density in the local parish, land cover type and distance to roads. We then assigned each ignition into subsets of five classes according to the resulting burned area:[5 ha, [50 ha,[100 ha,[250 ha,[500 ha. The probability of an ignition resulting in different burned area classes was modelled using binary logistic regression, and the relative importance, strength and signal (positive or negative) of the three explanatory variables compared across the models obtained for the different classes. Finally, we explored the implications of land cover and population density changes during the period 1990–2000 in Portugal for the likelihood of ignitions resulting in wildfires[500 ha. Population density was the more important variable explaining the resulting burned area, with the probability of an ignition resulting in a large burned area being inversely related to population density. In terms of land cover, ignitions resulting in large burned areas were more likely to occur in shrubland and forest areas. Finally, ignitions farther away from roads were more likely to result in large burns. The current land cover trends (decrease of agricultural land and increase in shrublands) and population trends (decline in population densities except near the coast) are increasing the probability that ignitions will result in large fires in vast regions of the country.

Percentage of basal area was used to evaluate tree species diversity in forest stands from 1995 and 2005 National Forest Inventories sample plots. The analysis was carried out at the PROF region level (Forest Management Regional Plans) and statistical Chi-square test was performed to verify if the changes occurred between 1995 and 2005 in the distribution of the number of tree species per sample plot were significant. Eight PROF regions show significant changes. For each of those regions, we illustrate forest composition and the diversity changes are outlined by the evaluation of Hill series for 1995 and 2005.------------------------Para a avaliação da diversidade de espécies arbóreas dos povoamentos florestais recorreu-se à quantificação da percentagem da área basal das espécies florestais que compõem as parcelas de amostragem dos Inventários Florestais Nacionais (IFN) de 1995 e 2005. A análise foi realizada ao nível das unidades estabelecidas pelas regiões PROF (Planos Regionais de Ordenamento Florestal) para as quais se verificou através do teste do qui-quadrado se, entre os anos de 1995 e 2005, tinham ocorrido alterações significativas relativamente à distribuição do número de espécies de árvores por parcela de amostragem. Para as oito regiões que apresentaram alterações significativas descreve-se a constituição da sua floresta e caracteriza-se a alteração da diversidade verificada através do cálculo das séries de Hill para 1995 e 2005.

The present work describes and analyzes the recent evolution of wood production from maritime pine (Pinus pinaster Aiton) and eucalyptus (Eucalyptus sp.) in a context that takes in account their potentiality to supply raw material for wood base industries. The improvements, from nineteen century to present time, on the methodologies associated with land inventories, with emphasis on national forest inventories, are also described, as well as the time series results for areas, volumes and annual increments, published in the scope of national forest inventories. The evolution of these parameters shows that, in the future, the availability of wood produced on national forests is largely dependent on the increase of forest productivity. To accomplish this objective the necessary actions will involve the increment of forest active management, genetic improvement and better allocation of forest species with higher potential for wood production, namely of maritime pine and eucalyptus

Wildfires are a recurrent disturbance in the Mediterranean Basin. However, managers from this region are confronted with a lack of information on the effects of fire on most woody species, which is required for defining sustainable forest management strategies. Following a large wildfire in central Portugal (2003), we surveyed the area during the first year and assessed the vegetative condition of 1040 burned trees from 11 different species. Among those trees, 755 individuals were selected and monitored annually for 4 years. At the end of the study, almost all the broadleaved trees survived, while most coniferous died. In spite of the low mortality observed in broadleaves, most were top-killed and regenerated only from basal resprouts, which implies a slow recovering process. Quercus suber, however, showed vigorous post-fire crown resprouting and was the most resilient species. We fitted logistic regression models to predict the probability of individual tree mortality and top-kill from fire injury indicators and tree characteristics. Besides the differences between the two main functional groups (coniferous, broadleaved), bole char height and crown volume scorched or consumed were important predictors of tree responses. Additionally, the main factor determining crown mortality on broadleaved species was bark thickness. The selected models performed well when tested with independent data obtained on four other wildfires. These models have several potential applications and can be useful to managers making pre-fire or post-fire decisions in mixed forest stands in the western Mediterranean Basin.

O presente trabalho descreve e analisa o contexto das fileiras do papel e do cartão e das embalagens integrando as fases de transformação industrial até aos produtos finais, numa perspectiva de fileira. São caracterizados os fluxos de produção, a estrutura das empresas e do trabalho, nas diferentes fases do ciclo produtivo, e as especificidades associadas aos mercados interno e externo. A descrição das variáveis analisadas demonstra a importância económica destas fileiras no contexto nacional, evidenciando a sua relevância enquanto actividades onde as exportações merecem destaque, assim como o generalizado bom desempenho dos indicadores económicos, de que são exemplo a produtividade do trabalho e os salários praticados. The present work describes and analyses the context of the paper and paper board sector and that of wood, paper and paper board wrapping and packaging sector, integrating the phases of industrial transformation up to the final products. The production flows are characterized, as well as the structure of the enterprises and workforce at the different phases of the productive cycle. The specificities associated with the domestic and external markets are also analysed. The description of the variables shows the economic importance of these sectors in the national context, attesting the significance of the exportations, as well as the generalized good performance of macroeconomic indicators as, for example, the labour productivity and the salaries. Ce travail décrit et analyse le contexte des filières du papier et du carton ainsi que des emballages en intégrant les phases de la transformation industrielle jusqu’aux produits finaux, dans une perspective de filière. Les flux de production, la structure des entreprises et du travail sont caractérisés dans les différentes phases du cycle productif ainsi que les spécificités associées aux marchés interne et externe. La description des variables analysées démontre l’importance économique de ces filières dans le contexte national, tout en soulignant leur importance en tant qu’activités dont les exportations sont importantes, tout comme la bonne performance générale des indicateurs économiques, dont les exemples sont la productivité du travail et les salaires.

Plant species richness in the Cape Verde archipelago is examined relative to island eco-geographical factors. Species-area and species-area-habitat relationships are analysed using the classical species-area model and the recently proposed species-choros model. The number of Xoristic zones (used to estimate the choros parameter) provides an adequate estimate of the potential habitat diversity, and the species-choros model achieved a better Wt with both total Xora and endemic species. In addition to area and habitat diversity, longitude also emerges as an important determinant of species diversity, whereas latitude, minimum distance to the nearest island, and total rural population do not display any correlation. As in other insular ecosystems, the species richness (about 140 per 100 km2) is lower than in nearby mainland regions; the proximity to the desert areas of the Sahel can also be seen as related with this low value. The Xoristic heterogeneity in Cape Verde is high, as is usual in island ecosystems. In a comparative analysis of the species richness on the diVerent islands (using -values), Brava stands out as having the highest total Xora species densities, while for endemic Xora Brava and São Nicolau jointly occupy the leading position. The high diversity for both total and endemic species on Santo Antão, São Vicente, São Nicolau, Fogo and Brava reinforces their importance in conservation terms - in the case of most of them, something that is already recognized in the established network of protected areas

In the Iberian Peninsula Mediterranean oak forests have been transformed into a mosaic landscape of four main patch-types: forests, savannas, shrublands and grasslands. We used aerial photographs over a period of 45 years (1958–2002) to quantify the persistence and rates of transitions between vegetation patch-types in southern Portugal, where cork oak is the dominant tree species. We used logistic regression to relate vegetation changes with topographical features and wildfire history. Over the 45 years, shrublands have been the most persistent patch-type (59%), and have been expanding; forests are also persistent (55%) but have been decreasing since 1985; savannas and grasslands were less persistent (33% and 15%, respectively). Shrublands persistence was significantly correlated with wildfire occurrence, particularly on southern exposures after 1995. In contrast, forest persistence decreased with wildfire occurrence, and forests were more likely to change into shrublands where wildfire had occurred after 1995.