23 research outputs found
Nutrient and herbivore alterations cause uncoupled changes in producer diversity, biomass and ecosystem function, but not in overall multifunctionality
Altered nutrient cycles and consumer populations are among the top anthropogenic influences on ecosystems. However, studies on the simultaneous impacts of human-driven environmental alterations on ecosystem functions, and the overall change in system multifunctionality are scarce. We used estuarine tidal flats to study the effects of changes in herbivore density and nutrient availability on benthic microalgae (diversity, abundance and biomass) and ecosystem functions (N2-fixation, denitrification, extracellular polymeric substances -EPS- as a proxy for sediment cohesiveness, sediment water content as a proxy of water retention capacity and sediment organic matter). We found consistent strong impacts of modified herbivory and weak effects of increased nutrient availability on the abundance, biomass and diversity of benthic microalgae. However, the effects on specific ecosystem functions were disparate. Some functions were independently affected by nutrient addition (N2-fixation), modified herbivory (sediment organic matter and water content), or their interaction (denitrification), while others were not affected (EPS). Overall system multifunction remained invariant despite changes in specific functions. This study reveals that anthropogenic pressures can induce decoupled effects between community structure and specific ecosystem functions. Our results highlight the need to address several ecosystem functions simultaneously for better ecosystem characterization and management.Instituto de Limnología "Dr. Raul A. Ringuelet
Nutrient and herbivore alterations cause uncoupled changes in producer diversity, biomass and ecosystem function, but not in overall multifunctionality
Altered nutrient cycles and consumer populations are among the top anthropogenic influences on ecosystems. However, studies on the simultaneous impacts of human-driven environmental alterations on ecosystem functions, and the overall change in system multifunctionality are scarce. We used estuarine tidal flats to study the effects of changes in herbivore density and nutrient availability on benthic microalgae (diversity, abundance and biomass) and ecosystem functions (N2-fixation, denitrification, extracellular polymeric substances -EPS- as a proxy for sediment cohesiveness, sediment water content as a proxy of water retention capacity and sediment organic matter). We found consistent strong impacts of modified herbivory and weak effects of increased nutrient availability on the abundance, biomass and diversity of benthic microalgae. However, the effects on specific ecosystem functions were disparate. Some functions were independently affected by nutrient addition (N2-fixation), modified herbivory (sediment organic matter and water content), or their interaction (denitrification), while others were not affected (EPS). Overall system multifunction remained invariant despite changes in specific functions. This study reveals that anthropogenic pressures can induce decoupled effects between community structure and specific ecosystem functions. Our results highlight the need to address several ecosystem functions simultaneously for better ecosystem characterization and management.Instituto de Limnología "Dr. Raul A. Ringuelet
Avances en la resolución conjunta de los procesos costeros y portuarios para la predicción de la agitación en la bahía de Algeciras
Se agradece a la APBA la financiación dentro del proyecto “Algeciras Safeport”
Regional circulation patterns of Mediterranean Outflow Water near the Iberian and African continental slopes
The Mediterranean Outflow Water (MOW) is a dense water
mass originated in the Strait of Gibraltar. Downstream of the Gulf of Cádiz,
the MOW forms a reservoir region west of the Iberian continental slopes at a
buoyant depth of approximately 1000 m. This region plays a key role as the
main centre where the MOW is mixed and distributed into the North Atlantic.
The seafloor in this area is characterized by the presence of a complex
bathymetry with three abyssal plains separated by mountain chains. Although
the topographic features do not reach the surface, they influence ocean
flows at intermediate and deep ocean layers, conditioning the distribution
and circulation of MOW.
The Copernicus Marine Environmental Monitoring Service (CMEMS) Iberian–Biscay–Ireland (IBI) ocean reanalysis is used to provide a detailed view of the
circulation and mixing processes of MOW near the Iberian and African
continental slopes. This work emphasizes the relevance of the complex
bathymetric features defining the circulation processes of MOW in this
region. The high resolution of the IBI reanalysis allows us to make a
description of the mesoscale features forced by the topography. The
temperature, salinity, velocity, transport, and vorticity fields are
analysed to understand the circulation patterns of MOW. The high-resolution
circulation patterns reveal that Horseshoe Basin and the continental
slope near Cape Ghir (a.k.a. Cap Rhir or Cabo de Aguer) are key areas controlling the mixing processes of MOW
with the surrounding water masses, mainly North Atlantic Central Water (NACW)
and Antarctic Intermediate Water (AAIW). The water mass
variability is also analysed by means of composite analysis. Results
indicate the existence of a variability in the MOW tongue which retracts and
expands westwards in opposition to the movement of the underlying North
Atlantic Deep Water.</p
Análisis del cambio climático en las costas españolas a lo largo del siglo XXI
Trabajo presentado en el Encuentro Oceanografía Física Española, celebrado en Las Palmas de Gran Canaria, España, del 11 al 13 de junio de 2014Peer Reviewe
Impact of climate change scenarios in the Mediterranean Sea from a regional ocean model
Póster presentado en la 2012 General Assembly de la European Geosciences Union (EGU), celebrada del 22 al 27 de abril de 2012 en Viena (Austria)Peer Reviewe
A propósito de un caso de xantoma tendinoso bilateral del Aquiles : estudio clínico, analítico y terapéutico
Los autores presentan un caso de Xantoma Tendinoso del Aquiles. Se analizan las causas de la aparición de dicha entidad clínica y se discuten las indicaciones quirúrgicas de la misma, así como las técnicas quirúrgicas a emplear