Browsing Departament de Ciències Ambientals by Subject "502"

At the edge of aquatic systems: intermittent streambed microbial communities’ responses to hydrological alterations

Gionchetta, Giulia (Date of defense: 2019-10-25)

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 ...

Biofilm responses to flow intermittency in Mediterranean rivers

Colls Lozano, Miriam (Date of defense: 2020-07-31)

Currently, global change is promoting the spatiotemporal occurrence of temporary streams, altering fluvial ecosystem function and structure, and the ecosystem services they provide. To effectively protect fluvial ecosystems, ...

Climate change and Mediterranean ecosystems: plant and soil responses to UV radiation and water availability before and after a perturbation

Díaz Guerra, Laura (Date of defense: 2017-07-21)

Taking into account the expected changes in solar UV levels, precipitation and fire regime in the Mediterranean basin, the main goal of this thesis was to evaluate the effects of UV radiation (UV-A and UV-B) and diminished ...

Contribució al coneixement de variables geoambientals en l'àmbit de la Costa Brava (Girona)

Geis Nielsen, Christian (Date of defense: 2005-06-28)

La tesi doctoral desenvolupada, emmarcada dins del camp de les Ciències Ambientals, aplica la Geologia Ambiental orientada al coneixement dels processos i recursos geològics de cara a la planificació i a l'ordenació del ...

Disentangling the complexity of chemical and physical stressors impacting river systems

Sabater Liesa, Laia (Date of defense: 2021-01-29)

Humanity has always been closely linked to rivers, benefiting from their resources while producing impacts associated with their activity.Thus, river systems have been exposed to multiple stressors, which have affected the ...

Dissecting the assembly process of benthic communities from Neotropical streams

González Trujillo, Juan David (Date of defense: 2020-07-30)

I used the metacommunity framework to dissect the relative influences of dispersal (in ecological and evolutionary timeframes), selection (driven by abiotic factors) and ecological drift on the assembly process of freshwater ...

Distribution of diatom communities in agricultural and mining watersheds of Southwest Spain

Urrea Clos, Gemma (Date of defense: 2010-11-05)

Els sistemes aquàtics continental representen un dels ecosistemes més amenaçats a nivell mundial, com a conseqüència de l'ús intensiu quel'home en fa. La conca del Guadiana no està lliure d'aquestes pressions antròpiques. ...

Efecte de la formiga argentina en la pol·linització de diverses espècies mediterrànies

Blancafort Pujols, Xavier (Date of defense: 2005-12-02)

Les inflorescències on és present la formiga argentina reben menys visitants, a les zones envaïdes, a més, desapareixen la majoria d'espècies de formigues autòctones, algunes de les quals podrien ser pol·linitzadores ...

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 ...

Estructura i dinàmica del sistema bentònic en llacunes costaneres dels aiguamolls de l'Empordà

Gascón Garcia, Stéphanie (Date of defense: 2003-12-12)

S'ha estudiat l'estructura i dinàmica del sistema bentònic de llacunes costaneres de la maresma dels aiguamolls de l'Empordà (NE de la península Ibèrica) i els factors que les determinen. Amb aquesta finalitat es van prendre ...

Flow alteration and wastewater inputs effects on freshwater communities in Mediterranean rivers

Mor Roy, Jordi-René (Date of defense: 2019-09-19)

Mediterranean rivers are characterized by high hydrological variability and heterogeneity of habitats, placing themselves amongst arid and temperate climates, and are associated with high biological diversity. On the ...

Mediterranean macroalgal forests under threat: the effects of ongoing climate change and design of restoration methods

Verdura Brugarola, Jana (Date of defense: 2021-06-04)

Macroalgal forests represent some of the most productive and biodiverse habitats on Earth. In the Mediterranean Sea, species of the genus Cystoseira sensu lato dominate the well-preserved subtidal rocky habitats where ...

Metacommunities and biodiversity patterns in Mediterranean temporary ponds: the role of pond size, network connectivity and dispersal mode

Tornero Pinilla, Irene (Date of defense: 2020-03-13)

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 ...

Multiple stressor effects on river biofilm communities: from community composition to ecosystem processes using experimental mesocosms

Romero Blanch, Ferran (Date of defense: 2019-12-20)

Human exploitation of river ecosystems, together with the increasing pressure that represents climate change, is posing rivers worldwide at risk. In rivers, microorganisms are ecologically very important. Most of ...

Radiación ultravioleta y sequía: efectos sobre la fisiología y la descomposición de hojarasca de especies arbustivas mediterráneas en el contexto del cambio climático

Rodríguez Hidalgo, Claudia Marina (Date of defense: 2020-09-09)

Various climatic models predict an increase in the ultraviolet (UV) radiation and a reduction in the precipitation levels reaching in the Mediterranean Basin. Exposure of plants to different levels of UV radiation and water ...

Reintroduction of the Eurasian otter (Lutra lutra) in Muga and Fluvià basins (north-eastern Spain): viability, development, monitoring and trends of the new population

Saavedra Bendito, Deli (Date of defense: 2003-06-10)

Aquesta tesi es basa en el programa de reintroducció de la llúdriga eurasiàtica (Lutra lutra) a les conques dels rius Muga i Fluvià (Catalunya) durant la segona meitat dels 1990s. Els objectius de la tesi foren demostrar ...

Reproductive and condition status of “cold water” marine fish: new insights from a changing environment

Serrat Llinàs, Alba (Date of defense: 2019-04-10)

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 ...

Resilience of aquatic metacommunities: implications for disturbance recovery

Cunillera-Montcusí, David (Date of defense: 2020-02-21)

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 ...