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

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 the quality and origin of the dissolved organic matter (allochthonous versus au...

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Detalles Bibliográficos
Autor: Freixa Casals, Anna
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2016
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/363921
Acceso en línea:http://hdl.handle.net/10803/363921
Access Level:acceso abierto
Palabra clave:Biofilms
Rius
Rivers
Ríos
Mediterranean Region
Regió mediterrànea
Región mediterránea
River sediments
Sediments fluvials
Sedimientos fluviales
Canvis climàtics
Climatic changes
Cambios climáticos
Microorganisms
Microorganismes
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574
577
Descripción
Sumario: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 the quality and origin of the dissolved organic matter (allochthonous versus autochthonous) and the different hydrological periods (drought versus base flow) highly modified the biofilm functioning and composition. On the other hand, the two laboratory experiments showed that first, the decrease in dissolved oxygen in sediment depth determined the microbial organic matter degradation. And second, results also showed that warming river water increased the heterotrophy of the microbial communities and clearly modified the food web structure. In conclusion this thesis demonstrates that the structure and functioning of sediment biofilms change at different spatial and temporal scales and they are sensitive to the increase in water pollution and the effects of global climate change.