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Mestrado em Engenharia Florestal e dos Recursos Florestais - Instituto Superior de Agronomia This study characterized the composition and the diversity of macrofungal communities associated with four plots of montado situated in Grândola Hills, Southern Portugal, and evaluated the influence of soil parameters on ectomycorrhizal fungal diversity and abundance. Phosphorus, potassium, total nitrogen, organic matter concentrations and soil pH were the parameters determined. Differences in soil chemical features were found between studied plots. A total of 132 species of macrofungi were found in the study area being Laccaria, Russula and Cortinarius the most abundant genera. Also dissimilarities on macrofungal communities, particularly, on abundance and diversity, were registered among plots. The influence of soil parameters on ectomycorrhizal diversity and abundance was studied in the plots with values of biological spectrum higher than one, and in particular for the most frequent species Laccaria laccata, Cortinarius trivialis, Russula amoenolens and Russula subfoetens. Results showed that ectomycorrhizal diversity is negatively correlated with the increasing of extractable phosphorus concentration, and the abundance of ectomycorrhizal species responds differently to soil chemical characteristics. The present study allows us to understanding the influence of some soil features on ectomycorrhizal fungal diversity and abundance. Finally, the effects of management practices on ectomycorrhizal fungal diversity in this Mediterranean ecosystem are discussed.

Charcoal canker is a frequent Quercus suber disease that nowadays contributes to its decline in Portugal. It is caused by Biscogniauxia mediterranea,a wide dispersed endophytic fungus that may be present in symptomless trees, becoming more aggressive in susceptible stressed hosts. This work aims to clarify the fungus dispersal by airborne dispersion and transmission from a tree to its progeny through infected tissues. Thus a Hirst spore-trap and meteorological station were installed in the forest. The results confirmed that ascospores spread as airborne inoculum in natural conditions varying throughout the year. Precipitation is the main factor for ascospores release and wind the way of dispersal. The transmission of the fungus by infected tissues was evaluated in acorns and seedlings from declined and asymptomatic trees, in natural regeneration and in stump sprouting regeneration from infected trees. Although B. mediterranea is present in the seeds, it was not found in seedlings, indicating there is no vertical transmission of the disease. It was also found in natural regeneration in a reduced rate, not due to seed contamination but by early aerial infection. In stump sprouting the fungus was not detected, so it can be used to replace trees. O carvão do entrecasco é uma doença frequente de Quercus suber que atualmente contribui para o seu declínio em Portugal. Esta doença é provocada por Biscogniauxia mediterranea, um fungo endófito que pode estar presente em árvores assintomáticas, tornando-se agressivo em hospedeiros sob stress. Este trabalho tem como objetivo esclarecer a dispersão do fungo por via aérea e a transmissão através de tecidos infetados da árvore para a descendência. Assim, foram instalados no montado um aparelho capta-esporos tipo Hirst e uma estação meteorológica. Os resultados confirmaram que ascósporos dispersam-se no ar em condições naturais variando ao longo do ano. A precipitação é o principal fator para a libertação dos ascósporos e o vento o meio de dispersão. A transmissão do fungo por tecidos infetados foi avaliada em bolotas e plântulas de árvores degradadas e assintomáticas, em regeneração natural e em rebentamentos de toiça de árvores infetadas. Apesar de B. mediterranea estar presente nas sementes, não foi detetada nas plântulas, indicando que não há transmissão vertical da doença. Foi encontrado em taxa reduzida na regeneração natural, não pela contaminação de sementes, mas por infeção aérea precoce. Nos rebentamentos de toiça o fungo não foi detetado, pelo que poderão ser utilizados para substituição de árvores degradadas. Le charbon de la mère est une maladie fréquente du Quercus suber entrainant actuellement son déclin au Portugal. Cette maladie est causée par Biscogniauxia mediterranea, un champignon endophyte qui peut être présent dans les arbres asymptomatiques. Il devient plus agressif chez les hôtes sous stress. Ce travail vise à clarifier la dispersion du champignon dans l'air et la transmission à travers des tissus infectés de l'arbre à la descendance. Ainsi, un piège à spores Hirst et une station météorologique ont été installés dans la subéraie. Les résultats ont confirmé que les ascospores sont dispersées dans l'air dans les conditions naturelles variant tout au long de l'année. La précipitation est le principal facteur pour la libération des ascospores et le vent le milieu de la dispersion. La transmission du champignon par les tissus infectés a été évaluée dans les glands et les semis d'arbres dépérissants et asymptomatiques, dans la régénération naturelle et des rejets de souche des arbres morts contaminés. Bien que B. mediterranea soit présente dans les glands, il n'a pas été trouvé dans les semis, indiquant absence de transmission verticale de la maladie. Il a été trouvé en taux réduit dans la régénération naturelle, pas à cause de la contamination des glands, mais par une infection aérienne prématurée. Dans les rejets de souche le champignon n'a pas été détecté, de sorte qu'ils peuvent être utilisés pour remplacer les arbres dépérissants.

This paper assesses the private and social profitability of current strategies for managing processionary moth (Thaumetopoea pityocampa) in Portuguese pine forests, looking at economic and environmental costs and benefits. Costs include the expenses for forest treatment and the social costs of threats to human health (dermatitis amongst others); benefits are assessed in terms of both revenue and social benefits such as carbon fixation and recreation. The evaluation was done using Cost Benefit Analysis (CBA) as an analytical framework. While this tool is currently applied to forest and environmental assessment and specific applications to pest management strategies are to be found in agricultural economics, rather few attempts have been made in the field of forest pest management. In order to assess and comparewithewithout options, a case-study was analysed for the Setu´bal Peninsula, south of Lisbon, an area where extensive stands of maritime pine (Pinus pinaster) grow. The exercise has shown that CBA can be a valuable tool for assessing the economic and social profitability of pest management. The results demonstrate that the loss of revenues in the no-management option is not sufficient to make pest management profitable for private forest owners in the shortterm. Conversely, a social profit is gained as pest management minimizes health risks for humans and avoids possible recreational losses.