Universitat de Barcelona
Now showing items 50-69 of 80
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 ...
The overarching goal of this dissertation was to explore relationships between streamwater nitrogen (N) and the most representative primary uptake compartments (PUCs) in stream ecosystems (e.g. microbial biofilm, algae, ...
Desde los albores de la civilización, los ríos son una de las vías habituales usadas por el hombre para desprenderse de parte de sus desechos. Por ello, los sistemas fluviales han sido espectadores privilegiados de la ...
La finalidad de la presente obra es la de contribuir al conocimiento de la biología y ecología de los Digénidos representantes de la familia Brachylaimidae, mediante el estudio detallado del ciclo vital y de la evolución ...
The discipline of ecology is habitually divided up into a whole range of different specialities, and this thesis forms part of what is commonly known as "community ecology" (Diamond and Case 1986). To be more precise, my ...
Many nearshore temperate coastal ecosystems are strongly regulated by top-down control. This is particularly true of shallow macrophyte communities, where habitat structuring is heavily dependent on the ability of predators ...
En aquesta tesi doctoral s'han estudiat les causes de l'aparició de fenòmens hipòxics i anòxics en un sistema costaner estuarià micromareal com la badia dels Alfacs (Mediterrani NW), pel període comprès entre el final dels ...
