Final Report Summary - ARISTEUS (Environmental VARIableS RegulaTing DivErsity and FaUnal DistributionS in Canyon and Lower Slope Ecosystems of the Western Mediterranean)
Scientific summary
Major questions about the functioning of continental margin ecosystems concern their interrelationship / dependence on natural drivers, as they are strongly mediated by physical processes and potentially affected by anthropogenic and climate change perturbations. The main goal of the ARISTEUS project was to elucidate the physical (water column and near-bed current regime) and biogeochemical (sediment transport, seabed composition, input of particulate organic matter) factors regulating diversity and faunal distributions in canyon and lower slope ecosystems of the Western Mediterranean Sea. Results obtained by ARISTEUS have strengthened recent findings on physical exchange processes such as dense shelf water cascading (i.e. cooling and sinking of shelf waters that cascade through submarine canyons following a flushing pattern) that transfer large quantities of particulate organic matter from the continental shelf to the basin, directly affecting the functioning of deep-sea ecosystems. In addition, a new type of climate-driven event with a major impact to marine ecosystems has been identified and described. This is coastal storms which are associated with strong winds, high waves and intensified currents, and occasionally with heavy rains and flash floods, and are mostly known because of the serious damage they can cause along the shoreline and the threats they pose to navigation. Investigations framed in ARISTEUS have identified a storm occurring in the Western Mediterranean region in December 2008 as the most extreme storm in the area over the last 25 years, and have found that in spite of their catastrophic effect on coastal communities (or more exactly, thanks to it), storms of high magnitude largely contribute to the sustainment of the deep ecosystem through the episodic supply of large volumes of marine organic carbon mostly along submarine canyons. Overall, results from the ARISTEUS project add new views to the current understanding on the impacts that climate-driven phenomena may have on deep-sea ecosystems, and consequently, on their living resources.
Work performed and implementation of the project
ARISTEUS has been linked to the Spanish 'Integrated study of deep canyons and slopes of the Western Mediterranean Sea: An essential habitat' (PROMETEO project, reference No. CTM2007-66316-C02-01/MAR) that started in 2007 and lasted for 3 years. PROMETEO aimed at performing multidisciplinary research in the deep canyons and slopes of the northwestern Mediterranean Sea by integrating experts from various disciplines (geology, biology, physical oceanography, live resources, environmental science, marine sciences and engineering) and institutions (Consejo Superior de Investigaciones Científicas (CSIC), Spain; Universitat de Barcelona, Spain; Universitat Politècnica de Barcelona, Spain, Centre de Formation et de Recherche sur l'Environnement Marin (CEFREM), France) in order to make generic principals of the relationship between environmental variables and faunal distribution. PROMETEO gave ARISTEUS the ideal framework and the infrastructure, and ARISTEUS in turn provided PROMETEO with exclusive results.
In order to identify the environmental variables and how do these environmental variables influence biological communities three specific field tasks were achieved. In the first, a continuous measurement over one year of physical variables and biogeochemical processes in Blanes submarine canyon and the adjacent southern open slope was performed by means of an array of moorings lines with sediment traps (that collect downward settling particle fluxes) and currentmeters (that record current speed, current direction, temperature, salinity, and transmissivity). The second field task consisted in the seasonal sampling of superficial sediments to detect variations in the composition of the sediments in response to particle fluxes from the water column. Finally, a third task devoted to characterise the biogeochemical characteristics and temporal dynamics of organic matter discharged by rivers to the coastal zone nearby Blanes Canyon was also achieved.
All data and samples obtained were analysed in the laboratory to determine grain size distribution and composition and fluxes of key components such as organic carbon and its stable isotope 13C, which allows to identify its provenance (e.g. marine algae, soil-derived organic matter, woody debris). The occurrence of a storm while instruments were deployed allowed investigating how one of the most extreme coastal storms of the last decades lashing the Western Mediterranean rapidly impacted bottom currents, particle fluxes and surface sediments. In parallel, the work started in 2006 with the Marie Curie Intra-European project 'Biogeochemical and physical drivers of deep European margin ecosystems' (BIODEM) has been continued and more information regarding the impact of the dense shelf water cascading of winter 2005 - 2006 on bottom currents and settling particles has arisen. The results obtained in both types of climate-driven events studied (cascading and major storms) have been integrated with those obtained by biologists in order to establish relationships between environmental parameters and the characteristics of biological communities (abundance, biomass, diversity and species richness). Results have been published in specialised, high impact, scientific journals, and presented in scientific conferences and symposia.
The ARISTEUS project has allowed the researcher Anna Sanchez-Vidal to considerably increase her expertise in experiment planning and implementation (deployment and maintenance of mooring arrays), analytical techniques (grain size and isotopic analyses), project management (writing-up of scientific projects, reports, deliverables), and mentoring tasks (co-supervision of one PhD, co-supervision of three PhD in progress, supervision of several Master and Bachelor theses). Altogether make obvious that the fellow has now major competences in oceanographic research, which enhances her scientific excellence at national and international levels. It is worth mentioning that the ARISTEUS project has represented a good opportunity for the researcher to enlarge her record of publications in good-level peer-reviewed magazines, which made her CV a lot more competitive. She has recently been awarded a five years long 'Ramón y Cajal' contract by the Spanish Ministry of Research and Education. Such a contract enables the scientist to prepare applications for external funding both at national and international level and eventually lead them as principal investigator.
Major questions about the functioning of continental margin ecosystems concern their interrelationship / dependence on natural drivers, as they are strongly mediated by physical processes and potentially affected by anthropogenic and climate change perturbations. The main goal of the ARISTEUS project was to elucidate the physical (water column and near-bed current regime) and biogeochemical (sediment transport, seabed composition, input of particulate organic matter) factors regulating diversity and faunal distributions in canyon and lower slope ecosystems of the Western Mediterranean Sea. Results obtained by ARISTEUS have strengthened recent findings on physical exchange processes such as dense shelf water cascading (i.e. cooling and sinking of shelf waters that cascade through submarine canyons following a flushing pattern) that transfer large quantities of particulate organic matter from the continental shelf to the basin, directly affecting the functioning of deep-sea ecosystems. In addition, a new type of climate-driven event with a major impact to marine ecosystems has been identified and described. This is coastal storms which are associated with strong winds, high waves and intensified currents, and occasionally with heavy rains and flash floods, and are mostly known because of the serious damage they can cause along the shoreline and the threats they pose to navigation. Investigations framed in ARISTEUS have identified a storm occurring in the Western Mediterranean region in December 2008 as the most extreme storm in the area over the last 25 years, and have found that in spite of their catastrophic effect on coastal communities (or more exactly, thanks to it), storms of high magnitude largely contribute to the sustainment of the deep ecosystem through the episodic supply of large volumes of marine organic carbon mostly along submarine canyons. Overall, results from the ARISTEUS project add new views to the current understanding on the impacts that climate-driven phenomena may have on deep-sea ecosystems, and consequently, on their living resources.
Work performed and implementation of the project
ARISTEUS has been linked to the Spanish 'Integrated study of deep canyons and slopes of the Western Mediterranean Sea: An essential habitat' (PROMETEO project, reference No. CTM2007-66316-C02-01/MAR) that started in 2007 and lasted for 3 years. PROMETEO aimed at performing multidisciplinary research in the deep canyons and slopes of the northwestern Mediterranean Sea by integrating experts from various disciplines (geology, biology, physical oceanography, live resources, environmental science, marine sciences and engineering) and institutions (Consejo Superior de Investigaciones Científicas (CSIC), Spain; Universitat de Barcelona, Spain; Universitat Politècnica de Barcelona, Spain, Centre de Formation et de Recherche sur l'Environnement Marin (CEFREM), France) in order to make generic principals of the relationship between environmental variables and faunal distribution. PROMETEO gave ARISTEUS the ideal framework and the infrastructure, and ARISTEUS in turn provided PROMETEO with exclusive results.
In order to identify the environmental variables and how do these environmental variables influence biological communities three specific field tasks were achieved. In the first, a continuous measurement over one year of physical variables and biogeochemical processes in Blanes submarine canyon and the adjacent southern open slope was performed by means of an array of moorings lines with sediment traps (that collect downward settling particle fluxes) and currentmeters (that record current speed, current direction, temperature, salinity, and transmissivity). The second field task consisted in the seasonal sampling of superficial sediments to detect variations in the composition of the sediments in response to particle fluxes from the water column. Finally, a third task devoted to characterise the biogeochemical characteristics and temporal dynamics of organic matter discharged by rivers to the coastal zone nearby Blanes Canyon was also achieved.
All data and samples obtained were analysed in the laboratory to determine grain size distribution and composition and fluxes of key components such as organic carbon and its stable isotope 13C, which allows to identify its provenance (e.g. marine algae, soil-derived organic matter, woody debris). The occurrence of a storm while instruments were deployed allowed investigating how one of the most extreme coastal storms of the last decades lashing the Western Mediterranean rapidly impacted bottom currents, particle fluxes and surface sediments. In parallel, the work started in 2006 with the Marie Curie Intra-European project 'Biogeochemical and physical drivers of deep European margin ecosystems' (BIODEM) has been continued and more information regarding the impact of the dense shelf water cascading of winter 2005 - 2006 on bottom currents and settling particles has arisen. The results obtained in both types of climate-driven events studied (cascading and major storms) have been integrated with those obtained by biologists in order to establish relationships between environmental parameters and the characteristics of biological communities (abundance, biomass, diversity and species richness). Results have been published in specialised, high impact, scientific journals, and presented in scientific conferences and symposia.
The ARISTEUS project has allowed the researcher Anna Sanchez-Vidal to considerably increase her expertise in experiment planning and implementation (deployment and maintenance of mooring arrays), analytical techniques (grain size and isotopic analyses), project management (writing-up of scientific projects, reports, deliverables), and mentoring tasks (co-supervision of one PhD, co-supervision of three PhD in progress, supervision of several Master and Bachelor theses). Altogether make obvious that the fellow has now major competences in oceanographic research, which enhances her scientific excellence at national and international levels. It is worth mentioning that the ARISTEUS project has represented a good opportunity for the researcher to enlarge her record of publications in good-level peer-reviewed magazines, which made her CV a lot more competitive. She has recently been awarded a five years long 'Ramón y Cajal' contract by the Spanish Ministry of Research and Education. Such a contract enables the scientist to prepare applications for external funding both at national and international level and eventually lead them as principal investigator.