Universitat de Girona
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Inland waters are amongst the most diverse and impacted ecosystems globally, and they host many endangered taxa. Cyprinodontiforms are at the forefront of endangered freshwater fishes in Europe, with more than 80% of the ...
Small pelagic fish play an important ecological role mainly due to their contribution in transferring energy from low to higher trophic levels. Likewise, the capture of these species is in many cases an important nutritional ...
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 ...
Pyrenean headwater streams are singular ecosystems with a particular seasonal pattern. They sustain a unique biodiversity especially sensitive to environmental change. Because of this, their ecosystem structure and function ...
This thesis shows how the metals of natural and anthropic origin change significantly the composition of the prokaryotic communities (mainly the composition of bacteria). The β-diversity is the most sensitive variable to ...
Biogas is a highly recognized alternative to fossil fuels towards a sustainable energy production. Massive use of biogas depends on the removal of contaminants that may affect performance of processing equipment and energy ...
We sampled the macrofaunal metacommunities in four networks of Mediterranean temporary ponds covering a wide range of pond sizes and different spatial extents. 1) In the smallest pond network, pond size was not related to ...
During the last years, there has been an increase in the number and intensity of disturbances, and their consequences related with global change, which have corroborated the already forecasted scenarios. One example are ...
Hydrological drought is a process of natural desiccation mainly due to large shortage of rainfall events. Reduced precipitations and prolonged droughts are spreading worldwide and threaten the integrity of aquatic ...
Nitrogen pollution in water is common in our environment, especially in places affected by agriculture and livestock, industry or wastewater discharge areas. Ammonium and nitrate are the most common pollutants and can be ...
Exploited marine fish species with an affinity for cold waters inhabiting close to the warmer edge of their distribution area are exposed to stress caused by fishing and climate change. Three case studies of “cold water ...
The main aim of this thesis was to establish a link between the urban origin of chemical contamination (e.g. PhACs) and other stressors, particularly associated to water scarcity (Chapter 1, 2, and 3). Research has been ...
Based on the current knowledge about biofilm ecotoxicology and arsenic biogeochemistry in freshwater ecosystems, this thesis studied, under realistic environmental concentrations, i) the role of benthic biofilms in the ...
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 ...
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 ...
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 ...
This doctoral thesis studies the abundance, diversity, seasonal dynamics and activity of Epsilonproteobacteria in a meromictic basin of Lake Banyoles during three year cycles. We applied a complementary array of molecular ...
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 ...
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 ...
Denitrifying biocathodes are used to treat nitrogen contaminated water resources. The present PhD dissertation have been characterized different bacterial families with a relevant role in denitrification process. Different ...
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 ...
This thesis aims to contribute to the understanding of the invasive success of two invasive fishes (Gambusia affinis and G. holbrooki). We reviewed four Internet databases and the literature to clarify their introduction ...
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 ...
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 ...
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 ...
Streams experiencing a recurrent non-flow phase (i.e., flow intermittency) are characteristic of world regions with arid and semi-arid climates, where Mediterranean regions are part of. During non-flow streambed sediments, ...
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 ...
The present thesis aims to evaluate the use of antioxidant enzyme activities (AEA) of biofilm communities as biomarkers of metal pollution (mainly Zn) in fluvial ecosystems. In order to test AEA as biomarkers of metal ...
The main goal of this thesis is to investigate the effects of consequences of global change on fluvial biofilms. To achieve this objective a multi-marker approach has been used at different experimental scales. Our results ...
Metal pollution in rivers is in great concern with human activities in the fluvial watershed. This thesis aims to investigate the potential use of chl-a fluorescence parameters as biomarkers of metal toxicity, and to find ...
Man-made wetlands are often created to compensate for the loss or degradation of natural wetlands, but little is known about the processes taking place in these artificial environments, especially at the community level. ...
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 ...
Per tal d’avaluar l’impacte de la contaminació en els ecosistemes aquàtics, aquesta tesi es centra en una aproximació multi-biomarcador en els biofilms. En complement dels biomarcadors clàssics, es va demostrar que les ...
Human activities have been interfering with the natural biogeochemical cycles of trace elements since the ancient civilizations. Although they are inaccessible and remote, high mountain lake catchments are irrefutably ...
La comunitat bentònica dels ecosistemes fluvials processa una gran quantitat de la matèria orgànica que arriba als rius. L'origen de les entrades de material (autòctones o al·lòctones), la seva composició química i la seva ...
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 ...
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). ...
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 ...
El presente estudio tiene como objetivo proporcionar una base de conocimiento sólida para la restauración ecológica de ríos, basada en la respuesta de comunidades acuáticas a cambios en la conectividad hídrica, factores ...
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 ...
Aquesta tesi tracta la jerarquia i l'heterogeneïtat dels sistemes fluvials que afecten l'estructura de les comunitats bentòniques de diatomees. A nivell regional, es van buscar diferents grups de punts i les seves espècies ...
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 ...
L'objectiu d'aquest estudi és el d'investigar sobre l'ús de matèria orgànica per part dels fongs i bacteris que colonitzen diferents substrats bentònics en rius Mediterranis i analitzar l'efecte dels factors ambientals i ...
L'objectiu principal del treball de recerca és aprofundir en el coneixement del grup de Bacteris Verds del Sofre (BVS) des del punt de vista de la relació amb la salinitat. L'estudi s'ha restringit als representants ...
La contínua descàrrega de nutrients, sobretot fosfats i nitrogen, és la major causa d'eutrofització dels ecosistemes aquàtics. Els sistemes de tractament basats en aiguamolls construïts s'han emprat per reduir ells nivells ...
L'objectiu d'aquesta tesi és aportar les primeres dades sobre l'ecologia del silur (Silurus glanis) introduït a la Península Ibèrica i estimar els seu impacte ecològic sobre la biota nativa. Es van mostrejar les comunitats ...
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 ...
Actualment una de les principals amenaces a la biodiversitat és la introducció d'espècies. Revisant 26 variables de les 69 espècies de peixos continental de la Península Ibèrica concloem que la filogènia, variabilitat i ...
Se ha estudiado la dinámica del fitoplancton en las lagunas costeras de Aiguamolls de l'Empordà. El fitoplancton esta sujeto principalmente al control "bottom-up", la variabilidad hidrológica y la disponibilidad de nutrientes ...
L'agricultura i la industrialització han causat un augment significatiu del nombre d'ambients rics en amoni. La presència de compostos nitrogenats redueix la qualitat de l'aigua, causant problemes de toxicitat, deteriorant ...
En el marc d'un projecte més ampli sobre la comunitat de peixos de la conca lacustre de Banyoles, s'ha estudiat la distribució espacial de les diferents espècies així com l'ús que aquestes fan de l'hàbitat. El poblament ...
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 ...
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 ...
Before 1910, the fish assemblage of Banyoles Lake (Catalonia, Spain) consisted of: eel (Anguilla anguilla), Mediterranean barbel (Barbus meridionalis), freshwater blenny (Bennius fluviatilis), three-spined stickleback ...
