Now showing items 18-37 of 54

    Effects of global change on fish assemblages in Mediterranean streams 

    Merciai, Roberto (Date of defense: 2016-09-30)

    L'objectiu d'aquesta tesi és de'explorar alguns aspectes de l'impacte humà sobre les poblacions de peixos i altres components dels ecosistemes fluvials Mediterranis de Catalunya. Es va mostrar com els peixos del Riu Llobregat ...

    Effects of land uses and climate variability on the water quality of Mediterranean rivers: towards a regional vision of global change 

    Aguilera Becker, Rosana (Date of defense: 2015-03-10)

    This work investigated the effect of global change phenomena, particularly land use and climatic changes, on water quality patterns in Mediterranean rivers. A hybrid process-based and statistical model (SPARROW) was applied ...

    Effects of priority and emerging pollutants on river biofilms 

    Ricart Viladomat, Marta (Date of defense: 2011-01-14)

    L'activitat humana representa una de les majors causes d'entrada d'una gran varietat de substàncies en els ecosistemes fluvials. L'objectiu principal d'aquest treball es investigar els efectes que els tòxics orgànics poden ...

    Estudi dels carotenoides en espècies marrons de bacteris verds del sofre: diversitat, eco-fisiologia i regulació 

    Mallorquí Fernández, Noemí (Date of defense: 2003-12-11)

    El present treball es centra en l'estudi a diferents nivells dels carotenoides de les espècies marrons de Bacteris Verds del Sofre (GSB, de l'anglès Green Sulfur Bacteria). L'objectiu global ha estat el d'esbrinar quina ...

    Estudio de la red trófica microbiana en lagunas someras: autotrofia versus heterotrofia 

    Àvila Izquierdo, Núria (Date of defense: 2017-05-26)

    Autotrophic and heterotrophic microorganisms are two essential functional units in the microbial food web of aquatic ecosystems. They play a key role in nutrient cycling and carbon flow and influence the structure, composition ...

    Explaining the invasive success of the eastern mosquitofish (Gambusia holbrooki): the role of temperature 

    Carmona Catot, Gerard (Date of defense: 2013-12-09)

    The eastern mosquitofish (Gambusia holbrooki) is one of the most widely distributed and invasive inland fish. It is known that it has not been established in northern Europe or upstream of rivers, where the temperature is ...

    Factors regulating the invasion of two Mediterranean anurans. The role of niche conservatism, species interaction and habitat selection 

    Escoriza, Daniel (Date of defense: 2015-03-02)

    Amphibians are a group in worldwide decline. The factors that are causing this decline are not well known, but could be multifactorial, related to the recent expansion of pathogens and habitat disturbance. One of these ...

    Fate and effects of copper in fluvial ecosystems: the role of periphyton 

    Serra Gasa, Alexandra (Date of defense: 2009-07-03)

    L'activitat humana és una de les majors causes d'elevades concentracions de nutrients i substàncies tòxiques en els ecosistemes fluvials. Entre la gran varietat de factors que alteren aquests ecosistemes, l'eutrofització ...

    Fish as ecological indicators in Mediterranean freshwater ecosystems 

    Benejam Vidal, Lluís (Date of defense: 2008-12-22)

    Podeu escriure el text directament o arrossegar-lo des d'un altre document<br/>L'objectiu d'aquesta tesi és contribuir a l'ús dels peixos continentals com a indicadors de l'estat ecològic a la conca Mediterrània. En el ...

    Food webs of Mediterranean coastal wetlands 

    Compte Ciurana, Jordi (Date of defense: 2010-07-21)

    En aquesta tesi doctoral s'han estudiat els efectes directes i indirectes de dos tipus d'espècies claus de la comunitat aquàtica dels aiguamolls de l'Empordà (aiguamolls costaners mediterranis amb una xarxa tròfica senzilla). ...

    Function and structure of river sediment biofilms and their role in dissolved organic matter utilization 

    Freixa Casals, Anna (Date of defense: 2016-02-18)

    The objective of this thesis was to study how sediment microbial communities in Mediterranean rivers used dissolved organic matter at different spatial and temporal scales. Results from the two field studies, showed that ...

    Heterogeneïtat pigmentària en bacteris fotosintètics verds: fisiologia i significació ecològica 

    Borrego i Moré, Carles (Date of defense: 1996-11-15)

    Green bacteria possess one of the most complexes antenna systems within the group of the photosynthetic microorganisms. One reason for this complexity is the high diversity of pigments antenna, the bacteriochlorophylls ...

    Hydrological alteration, critical swimming speed and life history in inland fish 

    Cano-Barbacil, Carlos (Date of defense: 2022-11-18)

    Fresh waters are among the most biodiverse ecosystems globally but, at the same time, also the most threatened. Serious threats to freshwater ecosystems are, for example, habitat alteration, invasive alien species and ...

    Impact of chlorophenols and heavy metals on soil microbiota: their effects on activity and community composition, and resistant strains with potential for bioremediation 

    Cáliz Gelador, Joan (Date of defense: 2011-12-13)

    Pollution by toxic compounds is one of the most relevant environmental damages to ecosystems produced by human activity and, therefore, it must be considered in environmental protection and restoration of contaminated ...

    Incidència de microorganismes i de compostos orgànics volàtils en l'aparició de defectes sensorials en suro 

    Prat i Botanch, Chantal (Date of defense: 2010-02-26)

    La incidència sobre el suro de defectes sensorials amb descriptors de florit-humitat és un dels principals problemes amb què s'enfronta la indústria surera. Els principals compostos relacionats amb aquest defecte son ...

    Influences of toxicants on freshwater biofilms and fish: from experimental approaches to statistical models 

    Tuulaikhuu, Baigal-Amar (Date of defense: 2016-06-10)

    The main aims of this thesis are: i) to evaluate arsenic toxicity in two major, interacting components of the freshwater ecosystem, biofilm and fish, to provide information on environmentally realistic exposures and on ...

    Insights into the distribution and ecological role of members of the archaeal Phylum Bathyarchaeota. From the global to the local scale 

    Fillol Homs, Mireia (Date of defense: 2017-03-23)

    The Phylum Bathyarchaeota is currently one of the most studied uncultured archaeal phyla. Bathyarchaeota are phylogenetically diverse, globally ubiquitous and especially abundant in marine subsurface sediments. Despite ...

    Leaf litter decomposition in Mediterranean streams: microbial processes and responses to drought under current global change scenario 

    Mora Gómez, Juanita (Date of defense: 2014-12-19)

    This thesis studied the principal environmental controlling factors and microbial mechanisms involved in leaf litter decomposition in Mediterranean intermittent streams. Additionally, drought disturbance in both Mediterranean ...

    Limnological characteristics and zooplankton community structure of Mediterranean coastal lagoons undergoing restoration 

    Badosa i Salvador, Anna (Date of defense: 2007-03-06)

    Entre 1999 i 2003 es va desenvolupar un projecte Life de restauració a la maresma de La Pletera, afectada per un pla urbanització, i a la llacuna del Ter Vell, amb un elevat grau d'eutròfia (aiguamolls del Baix Ter, NE ...

    Linking river sediment physical properties to biofilm biomass and activity 

    Ann, Vannak (Date of defense: 2015-06-30)

    River sediments are composed by a variety of grain sizes which determine their permeability and biogeochemistry. The aim of this thesis was to test whether differences in river sediment physical characteristics generate ...