Universitat de Barcelona
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El mejillón cebra, Dreissena polymorpha (Pallas, 1771), es conocido por ser una de las especies invasoras de agua dulce más dañinas, tanto desde el punto de vista ecológico como económico, a nivel mundial. Este exitoso ...
“Lake macroinvertebrates and the altitudinal gradient in the Pyrenees [Los macroinvertebrados lacustres y el gradiente altitudinal en los Pirineos]” is a thesis about freshwater macroinvertebrate communities inhabitting ...
Overall, this thesis is an attempt at approaching seagrass ecosystems from a landscape perspective, with the aim of increasing knowledge about the processes generating patterns at large spatial scales, and understanding ...
ENGLISH ABSTRACT:<br/><br/>The general aim of this thesis was to develop a theoretical framework in order to study large-scale animal movements and/or dispersal processes as random search strategies. The framework was ...
La major part de la concentració de carboni i nitrogen que arriba al Mediterrani des de l'Ebre és en forma dissolta, mentre que en el cas del fòsfor la concentració en la forma particulada pot ser més important, especialment ...
La disponibilidad y calidad del agua que se encuentra en los embalses depende de factores relacionados directamente con las características de la cuenca a la que pertenece el río embalsado, como las cargas de nutrientes ...
La revaluació a gran escala espacial (> de 300 Km) i mitjançant mètodes de quantificació directa, del impacte de l'herbivorisme en els ecosistemes de <i>Posidonia oceanica</i> va revelar pèrdues de biomassa foliar molt ...
The Mediterranean Basin is a climate-change hotspot of the world. Predicted reductions in annual precipitation, increases in mean temperature, and increases in the variability and occurrence of extreme droughts and heat ...
El estudio de los microorganismos en cultivo puro ha propiciado el desarrollo de la genética, la bioquímica y la biotecnología. Sin embargo, la ecología ha permanecido reticente a incorporar a los microorganismos en su ...
The main goal of this PhD thesis was the study of the ammonium oxidation process in high nutrient loaded urban streams. We aimed to unveil regulating factors and driving mechanisms from the organisms to the ecosystem scales ...
Se han realizado diferentes campañas en el tramo estuarino del Río Ebro para estudiar las condiciones estacionales del estuario y la pluma (CyTMAR, Comisión Interministerial de Ciencia y Tecnología, proyecto MAR96-1856, ...
The Systems Approach Framework (SAF) is a methodological framework designed to enhance the efficacy of human decision-making processes within social-ecological systems with regard to sustainability. The SAF was applied in ...
Se estudia por vez primera la morfología de todas las superficies de agua con al menos media hectárea de todo el Pirineo. Caracterizamos morfométricamente estos lagos en base a variables tradicionales, medidas en la ...
The amount of dissolved inorganic nitrogen delivered to streams and groundwater has substantially increased in the last decades due to anthropogenic impacts. This fact has stimulated research on processes related to the ...
A full understanding of nutrient cycling in lotic ecosystems is crucial given the increasing influence of human activities on the eutrophication of streams and rivers. However, existing knowledge about nutrient cycling in ...
Comparative studies between different enzyme labelled fluorescence (ELF) protocols and fluorescence quantification methods were performed to improve the quantification of single-cell phosphatase activity (PA) measurements ...
Si vol consolidar-se com a explotació econòmicament i ecològicament sostenible, la piscicultura ha de deslligar-se de la pesca mitjançant la reducció del contingut de farina de peix als pinsos. Aquesta fita pot ser assolida ...
The Gran Sabana (GS, Northern South America) is a humid savanna region (treeless savanna intermingled with forest patches) with a long history of vegetation changes under fire disturbances. A number of hypotheses seek to ...
L'objectiu general de la tesi era estudiar el senyal de pigments indicadors en diversos compartiments (columna d'aigua, sediment superficial i registre sedimentari) dels estanys d'alta muntanya dels Pirineus, per aprofundir ...
We studied the planktonic food web in the eutrophic Sau Reservoir (Catalonia, NE Spain) taking account of both spatial as well as temporal scales. We have analysed several longitudinal transects (sampling from the river ...
