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Ruas S.,University of Lisbon | Bergamini A.,Swiss Federal Institute of forest | Carvalho P.,Museu Nacional de Historia Natural e da Ciencia | Fontinha S.,IsoPlexis | Sim-Sim M.,University of Lisbon
Nova Hedwigia | Year: 2015

The distribution of bryophytes and lichens is influenced by topographic, geological and macroclimatic factors and by smaller-scale factors such as light and humidity. This study addresses the following questions in relation to Madeira’s laurel forest: a) How does the community composition of bryophytes and macrolichens react to environmental factors? b) Do different groups have different niches? c) Which species are associated with undisturbed areas of the forest? We sampled 92 circular plots occupying an area of 100 m2 that comprised four ground subplots and two trees where bryophytes and macrolichens were inventoried. We recorded environmental variables (e.g. rock cover) in the field and extracted additional variables from GIS maps. We performed two Canonical correspondence analyses for bryophyte and lichen communities (CCA) and an Indicator species analysis (ISA) to understand which species were associated with undisturbed forest. Temperature was closely related to the first ordination axes and was the most important environmental variable for both communities. Since temperature is strongly correlated to altitude, this gradient is best seen as a complex altitudinal gradient. The second important gradient structuring both bryophytes and macrolichen communities was human intervention (considered as detectable forest alteration by human activities). The results of mean comparisons between groups indicate that significant differences exist only between liverworts and mosses. Liverworts are linked to more humid and sheltered areas of the forest. Among the species obtained by the ISA, four are endemic bryophytes and four are macrolichens belonging to the 'New Index of Ecological Continuity'. Past and present human activities influence the community structure of both groups. Therefore, to assess the success of conservation measures, we suggest establishing a system based on monitoring indicator species. © 2015 J. Cramer in Gebr. Borntraeger Verlagsbuchhandlung, Stuttgart, Germany.


Santos V.F.,Museu Nacional de Historia Natural e da Ciencia | Callapez P.M.,University of Coimbra | Castanera D.,University of Zaragoza | Barroso-Barcenilla F.,Complutense University of Madrid | And 3 more authors.
Journal of Iberian Geology | Year: 2015

A recently discovered Early Cretaceous (early late Albian) dinosaur tracksite at Parede beach (Cascais, Portugal) reveals evidence of dinoturbation and at least two sauropod trackways. One of these trackways can be classified as narrow-gauge, which represents unique evidence in the Albian of the Iberian Peninsula and provides for the improvement of knowledge of this kind of trackway and its probable trackmaker, in an age when the sauropod record is scarce. These dinosaur tracks are preserved on the upper surface of a marly limestone bed that belongs to the Galé Formation (Água Doce Member, middle to lower upper Albian). The study of thin-sections of the beds C22/24 and C26 in the Parede section has revealed a microfacies composed of foraminifers, radiolarians, ostracods, corals, bivalves, gastropods, and echinoids in a mainly wackestone texture with biomicritic matrix. These assemblages match with the lithofacies, marine molluscs, echinids, and ichnofossils sampled from the section and indicate a shallow marine, inner shelf palaeoenvironment with a shallowing-upward trend. The biofacies and the sequence analysis are compatible with the early late Albian age attributed to the tracksite. These tracks and the moderate dinoturbation index indicate sauropod activity in this palaeoenvironment. Titanosaurs can be dismissed as possible trackmakers on the basis of the narrow-gauge trackway, and probably by the kidney-shaped manus morphology and the pes-dominated configuration of the trackway. Narrow-gauge sauropod trackways have been positively associated with coastal palaeoenvironments, and the Parede tracksite supports this interpretation. In addition, this tracksite adds new data about the presence of sauropod pes-dominated trackways in cohesive substrates. As the Portuguese Cretaceous sauropod osteological remains are very scarce, the Parede tracksite yields new and relevant evidence of these dinosaurs. Furthermore, the Parede tracksite is the youngest evidence of sauropods in the Portuguese record and some of the rare evidence of sauropods in Europe during the Albian. This discovery enhances the palaeobiological data for the Early Cretaceous Sauropoda of the Iberian Peninsula, where the osteological remains of these dinosaurs are relatively scarce in this region of southwestern Europe. Therefore, this occurrence is also of overall interest due to its impact on Cretaceous Sauropoda palaeobiogeography. © 2015, Universidad Complutense de Madrid. All Rights Reserved.


Santos V.F.,Museu Nacional de Historia Natural e da Ciencia | Santos V.F.,University of Coimbra | Callapez P.M.,University of Coimbra | Rodrigues N.P.C.,Museu Nacional de Historia Natural e da Ciencia
Cretaceous Research | Year: 2013

Fieldwork carried out during the past few years in the Algarve region (Portugal) has allowed the description of dinosaur tracks for the first time in the Mesozoic Algarve Basin. Five track levels of Early Barremian age have been described from the Santa and Salema tracksites situated near Vila do Bispo (southwest Algarve). These comprise theropod and iguanodontian footprints (Iguanodontipus isp. was identified at the Santa tracksite). A sequence of subcircular and tridactyl impressions with a characteristic morphology of ornithopod footprints with a high pace angulation value made it possible to determine how erosion changes the print morphology and to understand the sequences of subcircular impressions with a high value of pace angulation in the track record. These dinosaur footprints are preserved in marginal-marine carbonate sediments of a large inner shelf palaeoenvironment with shoals and tidal-flat areas that were periodically exposed. The warm and dry climate favoured extensive growth of algal mats and the deposition of dolomitic sediments. The discovery of these track levels has also enabled the palaeobiogeographical data available for the Early Cretaceous Iguanodontia of the Iberian Peninsula and southwestern Europe to be refined. © 2012 Elsevier Ltd.


Sim-Sim M.,University of Lisbon | Ruas S.,University of Lisbon | Fontinha S.,University of Madeira | Hedenas L.,Swedish Museum of Natural History | And 2 more authors.
Systematics and Biodiversity | Year: 2014

On oceanic islands, the evolution of plants and animals with particular characteristics is favoured due to their isolation, populations normally comprising a large number of unique, endemic species. The Madeira and Selvagens archipelagos are considered biodiversity hotspots, containing an especially rich bryoflora. Due to its characteristically small size, this taxonomic group does not get much attention in conservation programmes. However, these plants are an important component of terrestrial ecosystems, representing a major part of biodiversity and playing a vital role in the ecosystem's functioning. As such, the development of the first Red List for Madeira and Selvagens Archipelagos has the potential to guide conservation efforts focused on taxa and habitats where threatened species and endemics are better represented. By applying the International Union for Conservation of Nature and Natural Resources (IUCN) criteria, recently revised to apply to small islands, it was possible to obtain the percentage of threatened taxa present in the archipelagos (23.6%), and for each habitat type. It was verified that high mountain habitats and the Laurel forest represent areas that host higher percentages of threatened taxa (29.5% and 22.2%). An important result of the present Red List is the identification of hotspots for bryophyte diversity, supporting the definition of reserves/microreserves. The information obtained can also be linked up with the Red Lists of other taxonomic groups to work towards the definition of a more holistic conservation strategy. © 2014 The Trustees of the Natural History Museum, London. All Rights Reserved.

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