Wind-induced changes in the dynamics of fluorescent organic matter in the coastal NW Mediterranean

Original research paperMarine biogeochemistry dynamics in coastal marine areas is strongly influenced by episodic events such as rain, intense winds, river discharges and anthropogenic activities. We evaluated in this study the importance of these forcing events on modulating seasonal changes in the marine biogeochemistry of the northwestern coast of the Mediterranean Sea, based on data gathered from a fixed coastal sampling station in the area. A 4-year (2011–2014) monthly sampling at four depths (0.5 m, 20 m, 50 m and 80 m) was performed to examine the time variability of several oceanographic variables: seawater temperature, salinity, inorganic nutrient concentrations (NO3−, PO43 − and SiO2), chlorophyll a (Chl a), dissolved organic carbon (DOC) and fluorescent dissolved organic matter (FDOM). FDOM dynamics was predominantly influenced by upwelling events and mixing processes, driven by strong and characteristic wind episodes. SW wind episodes favored the upwelling of deeper and denser waters into the shallower shelf, providing a surplus of autochthonous humic-like material and inorganic nutrients, whereas northerlies favored the homogenization of the whole shelf water column by cooling and evaporation. These different wind-induced processes (deep water intrusion or mixing), reported along the four sampled years, determined a high interannual environmental variability in comparison with other Mediterranean sampling sites. Graphical abstract Image 1 Download : Download high-res image (344KB)Download : Download full-size imageECOSER (CTM2011-15937-E), DOREMI (CTM2012-342949), SUAVE (CTM2014/ 23456/1) and ANIMA (CTM2015-65720) from the Spanish Ministerio de Economía y Competitividad (MINECO) and the Grup de Recerca Consolidat 2014SGR1179 and 2014SGR1029 financed by the Agència de Gestió d'Ajuts Universitaris i de Recerca (AGAUR) from the Generalitat de Catalunya; (JAEPre_2011_00923) from the Agencia Estatal Consejo Su perior de Investigaciones Científicas (CSIC) and the project FERMIO (MINECO, CTM2014-57334-JIN) co-financed with FEDER fundsVersión del editor3,25

Long-Term Changes in the Water Mass Properties in the Balearic Channels Over the Period 1996–2019

The analysis of a 24-year time series of Conductivity-Temperature-Depth (CTD) casts collected in the Balearic Channels (1996–2019) has allowed detecting and quantifying long-term changes in water mass properties in the Western Mediterranean. For the complete period, the intermediate waters have experienced warming and salting at rates of 1.4°C/100yr and 0.3–0.6/100yr for the Western Intermediate Water, and 1°C/100yr and 0.3–0.4/100yr for the Levantine Intermediate Water. The density of these two water masses has not changed. The deep waters, defined as those denser than 29.1 kg/m3, showed positive trends in temperature, salinity, and density (0.8°C/100yr, 0.2/100yr, and 0.02 kg.m–3/100yr, respectively). The high temporal variability of the upper layer makes the detection of long-term changes more difficult. Nevertheless, combining CTD data with temperature data from the oceanographic station at L’Estartit and simulated data from the NCEP/NCAR reanalysis, it can be established that the Atlantic Water increased its temperature at a rate of 2.1–2.8°C/100yr and likely its salinity at a rate of 0.6/100yr. The water column absorbed heat at a rate equivalent to 1–1.2 W/m2. All these trends are much higher than those reported in previous works (more than double in some cases). The warming of the water column produced an increase in the thermosteric component of sea level. However, this increase was compensated by the decrease in the halosteric component. Besides these changes, other alterations related to the Western Mediterranean Transition have been observed over shorter periods. The temperature and salinity of the intermediate waters increased before the winter of 2004/2005 and then the temperature and salinity of the deep waters increased dramatically in 2005. The density of the deep water reached values unprecedented before 2005. Deep and intermediate waters were uplifted by the presence of such dense deep waters. The arrival of warmer and saltier intermediate waters from the Eastern Mediterranean is also observed, mainly after 2010.Postprin

Cambio Climático en el Mediterráneo Español

Semi-enclosed and bounded by three continents, the Mediterranean sea is a region highly vulnerable to human activities, i.e.: the population surge along the coasts, the tourism pressure, the maritime traffic, the agriculture and the fishery exploitation, all have a potential impact on the Mediterranean environment. In addition, effective initiatives against the Global Climate Change need to be attempted in order to preserve our marine environment and to achieve a sustainable development of its resources. Prevention and adaptation to this new threat must be based on the rigorous and scientific knowledge accomplished through the systematic and continuous observation of the sea, and through the collection of multidisciplinary time-series and the subsequent analysis. This report responds to this necessity. The main goals of the Instituto Español de Oceanografía (IEO) are to generate scientific knowledge, as well as to assess and to inform the public about the state of the sea. The IEO is primary focussed on the study of the variety of phenomena influencing spanish coasts, including the process of Climate Change. To meet these objectives, a large set of actions have been planned. Some of them are already being implemented, such as a multidisciplinary observation system in the shelf and continental slope waters, or periodic scientific reports dealing with the detection and quantification of Climate Change effects and of other possible environmental impacts. The present report is the first of a series of future contributions. Besides the IEO, other Spanish institutions such as the ICM (CSIC), Puertos del Estado (PE), the IMEDEA (CSIC), the UMA, the UIB and the INM, involved in the monitoring, analysis and modelling of the Mediterranean sea, have also participated in it. The results show clear evidences of the effect of Climate Change in the physical properties of the mediterranean waters since 1948; in particular, the temperature and salinity increase of the deep waters, the accelerated rise of sea level since the early 1990s, and the air and sea surface temperature increase during the second half of the XX century.Versión del edito

The Biodiversity of the Mediterranean Sea: Estimates, Patterns, and Threats

The Mediterranean Sea is a marine biodiversity hot spot. Here we combined an extensive literature analysis with expert opinions to update publicly available estimates of major taxa in this marine ecosystem and to revise and update several species lists. We also assessed overall spatial and temporal patterns of species diversity and identified major changes and threats. Our results listed approximately 17,000 marine species occurring in the Mediterranean Sea. However, our estimates of marine diversity are still incomplete as yet—undescribed species will be added in the future. Diversity for microbes is substantially underestimated, and the deep-sea areas and portions of the southern and eastern region are still poorly known. In addition, the invasion of alien species is a crucial factor that will continue to change the biodiversity of the Mediterranean, mainly in its eastern basin that can spread rapidly northwards and westwards due to the warming of the Mediterranean Sea. Spatial patterns showed a general decrease in biodiversity from northwestern to southeastern regions following a gradient of production, with some exceptions and caution due to gaps in our knowledge of the biota along the southern and eastern rims. Biodiversity was also generally higher in coastal areas and continental shelves, and decreases with depth. Temporal trends indicated that overexploitation and habitat loss have been the main human drivers of historical changes in biodiversity. At present, habitat loss and degradation, followed by fishing impacts, pollution, climate change, eutrophication, and the establishment of alien species are the most important threats and affect the greatest number of taxonomic groups. All these impacts are expected to grow in importance in the future, especially climate change and habitat degradation. The spatial identification of hot spots highlighted the ecological importance of most of the western Mediterranean shelves (and in particular, the Strait of Gibraltar and the adjacent Alboran Sea), western African coast, the Adriatic, and the Aegean Sea, which show high concentrations of endangered, threatened, or vulnerable species. The Levantine Basin, severely impacted by the invasion of species, is endangered as well

Evolucón de la temperatura del mar entre 1973 y 1994, cerca de la Costa Catalana

Colloque Scientifique Pour qui la Méditerranée au 21ème siècle?, La Méditerranée : Variabilités Climatiques, Environnement et Biodiversité, 6-7 avril 1995, Montpellier, France.-- 6 pages, 3 figuresPeer Reviewe

Execució i dret penitenciari, febrer 2012

Material docent de la Universitat Oberta de Catalunya.Material docente de la "Universitat Oberta de Catalunya".Learning material of the "Universitat Oberta de Catalunya"

The physiological state of microplankton communities during contrasting situations in the NW Mediterranean

Symposium GLOBEC-IMBER España celebrado del 28-30 marzo de 2007 en Valencia.-- 1 pageTwo multidisciplinary cruises were performed in open sea waters of the NW Mediterranean, in the area of influence of the Nor-Balearic Front (NBF) and the two water masses bordering it. The objectives of the field work were to identify, quantify and establish relationships between the physical and chemical conditions, the structure of the planktonic communities and the biogeochemical fluxes in that area over different seasonal periods. Two cruises were conducted in two contrasting situations: during the summer stratification (September 2004) and during the spring bloom (March-April 2005) periods. In this last cruise, the physico-chemical and biological properties corresponding to the spring bloom were found at the North of the NBF while at the South of it corresponded to a post-bloom situation. In this communication, we discuss the distribution of the biochemical indicators of biomass (chlorophyll, protein and DNA) and of physiological state of the microbial communities, the RNA/DNA ratio, in relationship with other physico-chemical (temperature, salinity, inorganic nutrients) and biological (phytoplankton pigment composition, bacterial numbers, primary and bacterial productions) variables. Overall, the highest levels of protein and DNA concentrations were found during the bloom situation along with the highest values of the RNA/DNA ration, indicative of high metabolic activity and good physiological state. The lowest values were found during the stratification and intermediate ones in the post-bloom. Protein and DNA concentrations correlated well with phytoplankton biomass and bacterial abundances, respectively. The Protein/DNA ratio reflected the different proportion of autotrophic vs heterotrophic group