Tesis doctoral de Jesús Ortiz Dura
We monitored physical and chemical parameters, benthic macroinvertebrates, chlorophyll a, primary producers, and organic matter for one year (2001-2002) to assess the effect of a point source input on the taxa composition, community structure, functional organization, microhabitat distribution, and elemental stoichiometry in la tordera stream (catalonia, ne spain). below the point source, nutrient concetrations, discharge, and specific conductance were higher than at the upstream reach, while dissolved oxygen decreased. Total macroinvertebrate density was higher at the downstream reach than at the upstream reach. The two reaches did not differ in macroinvertebrate total biomass. On average, taxa richness at the upstream reach was 20% higher than at the downstream reach. Ordination analysis clearly separated the samples of the two reaches in the first axis and corroborated the effect of the point source on the benthic community. The two reaches followed a similar temporal pattern with respect to the distribution of taxa along the second axis. Higher similarities between the two reaches in taxa composition, densities and biomass after the spates of april and may 2002, suggest that flooding events may act as a reset mecahnism for benthic communities and play an important role is stream restoration. the two reaches did not differ in standing stocks of periphyton, vascular plants, cpom and fpom. Chorophyll a, filamentous algae, mosses, and spom concentrations were increased by the point source. Relative density of shredders was reduced at the downstream reach, whereas gatherers and filterers were enhanced. Relative biomass of shredders decreased below the point source as well, but gatherers diminished and predators increased. The relationships between density of functional feeding groups and their presumed food resources were rarely significant. The relationship for scrapers, gatherers, and filterers, but differed for shredders and predators. macroinvertebrate densit
Datos académicos de la tesis doctoral «Response of the benthic macroinvertebrate community to a point source in la tordera stream (catalonia , ne spain)«
- Título de la tesis: Response of the benthic macroinvertebrate community to a point source in la tordera stream (catalonia , ne spain)
- Autor: Jesús Ortiz Dura
- Universidad: Girona
- Fecha de lectura de la tesis: 30/06/2005
Dirección y tribunal
- Director de la tesis
- Angels Puig M.
- Tribunal
- Presidente del tribunal: sergi Sabater cortés
- isabel Muñoz gracia (vocal)
- Ana Basaguren del campo (vocal)
- Francisco Javier De quintana pou (vocal)