8 resultados para distribution patterns


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Miocene catfishes from Lisbon are dealt with. Two distinct sets of pectoral and dorsal pterygiophores are described. That from the Langhian V-b is referred to Arius sp. probably close to A. heudeloti. Another ser from the uppermost Burdigalian V-a may be ascribed to a bagrid, cf. Chrysichthys sp., identified for the first time in this region. The catfish and Lates association is sctrikingly similar to African, nilotic or sudanian ones as far as freshwaters are concerned. In marine, coastal environments, stenotherm warm-water forms (Polynemids, large barracudas and several sharks) indicate, as a model, faunas like chose from Cape Verde to northern Angola. There is some gradation for brackish waters (fig. 1). Catfishes and Lates probably migrated into the Iberian Peninsule in the lower Miocene. They are unknown after Langhian V-b except for a reappearance of Arius in the middle Tortonian VII-b. Decreasing temperatures and aridity account for local extinction at least in freshwaters. Expansion of these fishes have been made easier owing to the displacement of land masses chat narrowed or closed the marine waterway between Europe and Africa. Salinity tolerance is not necessarily the sole explanation for migration. Catfishes plus Lates associations colonized inland waters from both sides of the Paleomediterranean. Local extinction may have weighed more in the development of modern distribution patterns than migration.

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Miocene catfishes from Lisbon are dealt with. Two distinct sets of pectoral and dorsal pterygiophores are described. That from the Langhian V-b is referred to Arius sp. probably close to A. Beudeloti. Another set from the uppermost Burdigalian V-a may be ascribed to a bagtid, cf, Chrysichthys sp., identified for the first time in this region. The catfish and Lates association is strikingly similar to African, nilotic or sudanian ones as far as freshwaters are concerned. In marine, coastal environments, stenotherm warm-water forms (Polynemids, large barracudas and several sharks) indicate, as a model, faunas like those from Cape Verde to northern Angola. There is some gradation for brackish waters (fig. 1). Catfishes and Lates probably migrated into the Iberian Peninsule in the lower Miocene. They are unknown after Langhian V-b except for a reappearance of Arius in the middle Tortonian VII-b. Decreasing temperatures and aridity account for local extinction at least in freshwaters. Expansion of these fishes have been made easier owing to the displacement of land masses that narrowed or closed the marine waterway between Europe and Africa. Salinity tolerance is not necessarily the sole explanation for migration. Catfishes plus Lates associations colonized inland waters from both sides of the Paleomediterranean. Local extinction may have weighed more in the development of modern distribution patterns than migration.

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Dissertação para obtenção do Grau de Doutor em Engenharia do Ambiente

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In the central Algarve different soils have developed dependent on petrography of the parent material, slope position and recent erosion. The general patterns of occurence and distribution of different soils are described. The age of an eutric Nitosol is estimated and the relation between the soil and the parent material is investigated. Some different soils are described as examples with their chemical and physical properties. The water budget of soils is described in general with considerations concerning ground water recharge and run-off as well as in dependence of climate and of different site conditions.

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Thesis submitted for assessment with a view to obtaining the degree of Doctor of Political and Social Science of the European University Institute

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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Gestão de Informação

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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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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.