6 resultados para Maritime Pine


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In the present work, we studied a common outbreaking Lepidoptera species in Portuguese pine stands – Thaumetopoea pityocampa (Den. & Schiff.) - and one of its potential predators – Parus major (L.). The population dynamics of the immature stages of the Lepidoptera was studied in several types of Pinus pinaster (Aiton) plantations in three different areas: Setúbal Peninsula, Abrantes and National Pine Forest of Leiria. Location and plantation structure was the most important factors determining population density of T. pityocampa. Setubal and Abrantes was highly susceptible to attacks by the Lepidoptera, whereas Leiria had lower densities. Young and homogeneous pine stands was more susceptible to attacks than older and more heterogeneous pines stands. However, a desynchronized population of T. pityocampa, in which the larvae develops during summer instead of during winter, reached high densities also in Leiria. The impact of several mortality factors and climatic conditions on the immature stages of the insect (eggs and larvae), in normal and desynchronized populations are discussed, as well as possible evolutionary implications of the sudden appearance of the new version of T. pityocampa. The break of the pupa diapause and adult emergence times the annual life cycle of this insect. Adults from the desynchronized population emerged earlier than adults from the normal population, which in turn determined the change in the larvae development period. Different factors, potentially affecting the timing of adult emergence in both normal and abnormal populations are also discussed. To study P. Major, nest-boxes were placed in the areas of Setúbal and Leiria and they were monitored during three seasons. The nest-boxes increased the density of breeding and wintering birds in the studied pine plantations, indicating that a lack of natural holes are in fact a limiting factor for this populations. The earliest breeding start for this species was recorded in my study area, indicating that Portuguese coastal pines provide good breeding conditions earlier than in other areas of Europe and North Africa. This leads to an overlap between the end of the larvae stage of T. pityocampa and the beginning of the breeding season of P. major. Key-words: Thaumetopoea pityocampa, Parus major, Pinus pinaster, population dynamics, Portugal.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics

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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente

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Field Lab of Entrepreneurial Innovative Ventures

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A producer of 5.4 M bbl/d, totalling almost half of the consumption of the entire European Union, the Gulf of Guinea is a fundamental lifeline and maritime link between Europe, the Americas and Africa. Geographically positioned as a staging post for transit originating in Latin America and coupled with its relatively porous borders, the region is also the perfect stepping stone for contraband heading to European shores. While blessed with an enviable wealth of marine and mineral resources, the region is also plagued by an ever-increasing spectre of maritime piracy; accounting for around 30% of incidents in African waters from 2003 to 2011. It is for these reasons that this research centres around the issues of maritime security in the Gulf of Guinea, with a particular focus on the first two decades of the 21st century. This research looks to examine the overall picture of the present state of play in the area, before going on to provide an analysis of potential regional developments in maritime security. This research begins with the analysis of concepts/phenomena that have played a notable role in the shaping of the field of maritime security, namely Globalisation and security issues in the post-Cold War era. The ensuing chapter then focuses in on the Gulf of Guinea and the issues dominating the field of maritime security in the region. The penultimate chapter presents a SWOT analysis, undertaken as part of this research with the aim of correlating opinions from a variety of sectors/professions regarding maritime security in the Gulf of Guinea. The final chapter builds upon the results obtained from the abovementioned SWOT analysis, presenting a series of potential proposals/strategies that can contribute to the field of maritime security in the region over the coming years. This research draws to a close with the presentation of conclusions taken from this particular investigation, as well as a final overview of the earlier presented proposals applicable to the field of maritime security during the second decade of the 21st century.

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Ship tracking systems allow Maritime Organizations that are concerned with the Safety at Sea to obtain information on the current location and route of merchant vessels. Thanks to Space technology in recent years the geographical coverage of the ship tracking platforms has increased significantly, from radar based near-shore traffic monitoring towards a worldwide picture of the maritime traffic situation. The long-range tracking systems currently in operations allow the storage of ship position data over many years: a valuable source of knowledge about the shipping routes between different ocean regions. The outcome of this Master project is a software prototype for the estimation of the most operated shipping route between any two geographical locations. The analysis is based on the historical ship positions acquired with long-range tracking systems. The proposed approach makes use of a Genetic Algorithm applied on a training set of relevant ship positions extracted from the long-term storage tracking database of the European Maritime Safety Agency (EMSA). The analysis of some representative shipping routes is presented and the quality of the results and their operational applications are assessed by a Maritime Safety expert.