Cristina Sobrino

University of Vigo | UVIGO · Department of Ecology and Animal Biology

The sea surface microlayer (SML) is the thin interface between the ocean and the atmosphere, exhibiting an enrichment of hydrophobic and surfactant-like chemicals. Here we report the concentrations of organophosphate esters (OPEs), widely used flame retardants and plasticizers, in the SML and underlying waters from a north-south transect in the Atl...

Ocean acidification produces significant changes on phytoplankton physiology that can affect their growth and primary production. Among them, a downregulation of the enzymatic activity and the production of different cellular metabolites, including chlorophyll a (Chl a), has been observed in high CO2 cultures under stable conditions. However, the e...

Few studies have investigated ultraviolet (UV) radiation in the open ocean besides its harmful effects on organisms and influence on biogeochemical processes. Here, we assessed UV attenuation, with particular focus on UV‐B, across the (sub)tropical ocean during the Malaspina 2010 Circumnavigation. Vertical UV radiometer profiles together with Chl‐a...

Gene expression studies of marine phytoplankton under ocean acidification conditions are frequently based on relative measurements, with actin commonly used as a reference gene. Evidence from other organisms suggests that actin gene expression may be regulated by environmental conditions, compromising the role of actin as a reference gene. In this...

In parts of the Baltic Sea, the phytoplankton spring bloom communities, commonly dominated by diatoms, are shifting toward the co‐occurrence of diatoms and dinoflagellates. Although phytoplankton are known to shape the composition and function of associated bacterioplankton communities, the potential bacterial responses to such a decrease of diatom...

The global distribution of chromophoric dissolved organic matter (CDOM) in the euphotic layer of the Atlantic, Indian, and Pacific oceans (between 35° N and 40° S) was analyzed by absorption spectroscopy during the Malaspina 2010 circumnavigation. Absorption coefficients at 254 nm (a254) and 325 nm (a325), indices (a254/a365) and spectral slopes (b...

We determined the gross and net primary production (GPP and NPP) for the total community and the < 10 μm size fraction, the net release of dissolved organic carbon (DOC), and the microbial respiration in the Baltic Sea during the spring bloom. Samples (n = 126) were taken from the surface (3 m depth) covering most subbasins and different phases of...

The subtropical gyres occupy about 70% of the ocean surface. While primary production (PP) within these oligotrophic regions is relatively low, their extension makes their total contribution to ocean productivity significant. Monitoring marine pelagic primary production across broad spatial scales, particularly across the subtropical gyre regions,...

In the Baltic Sea, climate change has caused shifts in the phytoplankton spring bloom communities with co-occurrence of diatoms and dinoflagellates. Such changes likely affect the composition and function of associated bacterioplankton, key members of the carbon cycling, although the actual effects are unknown. To understand how changes in phytopla...

In the Baltic Sea, climate change has caused shifts in the phytoplankton spring bloom communities with co-occurrence of diatoms and dinoflagellates. Such changes likely affect the composition and function of associated bacterioplankton, key members of the carbon cycling, although the actual effects are unknown. To understand how changes in phytopla...

In the Baltic Sea, climate change has caused shifts in the phytoplankton spring bloom communities with co-occurrence of diatoms and dinoflagellates. Such changes likely affect the composition and function of associated bacterioplankton, key members of the carbon cycling, although the actual effects are unknown. To understand how changes in phytopla...

In the Baltic Sea, climate change has caused shifts in the phytoplankton spring bloom communities with co-occurrence of diatoms and dinoflagellates. Such changes likely affect the composition and function of associated bacterioplankton, key members of the carbon cycling, although the actual effects are unknown. To understand how changes in phytopla...

Microcosm experiments to assess the bacterioplankton's response to phytoplankton-derived organic matter obtained under current and future ocean CO2 levels were performed. Surface seawater enriched with inorganic nutrients was bubbled for 8 days with air (current CO2 scenario) or with a 1000 ppm CO2 air mixture (future CO2 scenario) under solar radi...

The biological production of calcium carbonate (CaCO3), a process termed calcification, is a key term in the marine carbon cycle. A major planktonic group responsible for such pelagic CaCO3 production (CP) is the coccolithophores, single-celled haptophytes that inhabit the euphotic zone of the ocean. Satellite-based estimates of areal CP are limite...

Over the past decades, as a consequence of human activity, there was an increase in nutrient inputs to the ocean and they are expected to enhance even more in the future. Coastal areas, accounting for a significant proportion of marine primary productivity, are the most vulnerable zones to anthropogenic impacts. The response of phytoplankton commun...

The biological production of calcium carbonate (CaCO3), a process termed calcification, is a key term in the marine carbon cycle. A major planktonic group responsible for such pelagic CaCO3 production (CP) are the coccolithophores, single-celled haptophytes that inhabit the euphotic zone of the ocean. Satellite-based estimates of areal CP are limit...

In recent decades, the phytoplankton community in parts of the Baltic Sea has shifted from diatom dominance to co-occurrence of diatoms and dinoflagellates during the spring bloom. We investigated whether this shift affects bacterial production (BP), abundance and community composition (BCC). Two mesocosm experiments were carried out with water fro...

Microcosm experiments to assess bacterioplankton response to phytoplankton-derived organic matter obtained under current and future-ocean CO2 levels were performed. Surface seawater enriched with inorganic nutrients was bubbled for 8 days with air (current CO2 scenario) or with a 1000 ppm CO2–air mixture (future CO2 scenario) under solar radiation....

Previous studies on the response of microbial plankton communities to nutrient inputs in coastal waters off NW Spain showed that phytoplankton not always responded to inorganic amendments, but was only stimulated when both, inorganic (nitrate, ammonium and phosphate) and organic (amino acids and glucose) nutrients were added jointly (mixed addition...

Short-term experiments indicate that seawater acidification can cause a decrease in the rate of calcification by coccolithophores, but the relationship between carbonate chemistry and coccolithophore calcification rate in natural assemblages is still unclear. During the Malaspina 2010 circumnavigation, we measured pri- mary production, calcificatio...

Anthropogenic pressures are changing the magnitude and nature of matter inputs into the ocean. The Ría de Vigo (NW Spain) is a highly productive and dynamic coastal system that is likely affected by such alterations. Previous nutrient-addition microcosm experiments conducted during contrasting hydrographic conditions suggested that heterotrophic ba...

This study shows the effects of solar UVR on the photosynthetic parameters and the production of both particulate and dissolved organic carbon (POC and DOC, respectively) of phytoplankton assemblages from oligotrophic areas of the southeastern Indian Ocean. Samples from the 20% PAR depth were incubated on deck under different intensities of 2 diffe...

Here it is reported the first detection of DV-chl a together with the usual chl a in the marine dinoflagellate Alexandrium ostenfeldii from the Baltic Sea. Growth response and photosynthetic parameters were examined at two irradiances (80 and 240 μmol photons ·m(-2 ·) s(-1) ) and temperatures (15° and 19 °C) in a divinylic strain (AOTV-OS20) vs a m...

The distribution of bioactive trace metals has the potential to enhance or limit primary productivity and carbon export in some regions of the world ocean. To study these connections, the concentrations of Cd, Co, Cu, Fe, Mo, Ni, and V were determined for 110 surface water samples collected during the Malaspina 2010 Circumnavigation Expedition (MCE...

The cyanobacterium Prochlorococcus is the smallest and most abundant photosynthetic organism on Earth [1]. Being a main global primary producer and ubiquist in the tropical and subtropical regions of the world’s oceans [2], it constitutes a good sentinel species for evaluating the effect of environmental stressors on oceanic photosynthesis. We deve...

Water samples from a coastal temperate area in the southwest Mediterranean Sea were incubated in 20 l microcosms under full-spectrum solar radiation. We studied the physiological response of phytoplankton to the interacting effects of 3 environmental factors expected to increase due to global change: CO2, nutrient loading and irradiance. Two differ...

We investigated the impacts of global climate change-associated abiotic factors on the species composition and size structure of coastal phytoplankton communities. Surface coastal water collected off the coast of Málaga (Spain) was incubated outdoors during a 7 d microcosm experiment. The natural phytoplankton communities were exposed to high and l...

We conducted a microcosm experiment aimed at studying the interactive effects of high CO2, nutrient loading and irradiance on the metabolism of a planktonic community sampled in the Western Mediterranean near the coast of Málaga. Changes in the metabolism of phytoplankton and bacterioplankton were observed for 7 d under 8 treatment conditions, repr...

We report on results of a microcosm experiment to study the interactive effects of elevated CO2, high organic and inorganic nutrient loading, and high irradiance on phytoplankton and bacterioplankton from the Mediterranean coastal ecosystem of the Alboran Sea. This experiment was part of the Group for Aquatic Productivity 9th international workshop...

We investigated the impacts of climate change-associated abiotic factors on the species composition and size structure of coastal phytoplankton communities. Surface coastal water collected off the coast of Málaga (Spain) was incubated outdoors during a 7 d microcosm experiment. The natural phytoplankton communities were exposed to high and low cond...

Coastal oceans are known to receive increasing inputs of reactive N as a result of the anthropogenic alteration of N cycling at the global scale, which may greatly alter nutrient supply to microbial plankton communities. The influence of nutrient availability (mainly inorganic N and P and/or organic C) on species composition has been widely reporte...

We describe the coupling between upper ocean layer variability and size-fractionated phytoplankton distribution in the non-nutrient-limited Bransfield Strait region (BS) of Antarctica. For this purpose we use hydrographic and size-fractionated chlorophyll a data from a transect that crossed 2 fronts and an eddy, together with data from 3 stations l...

To investigate factors controlling phytoplankton physiological state around the South Shetland Islands, phytoplankton abundance and structure, fluorescence properties, photo - protective pigment composition and physicochemical variables were studied. Nano phyto plank - tonic cells (<20 μm) contributed 84% of total chlorophyll a (chl a), except for...

Anthropogenically induced global climate change has important implications for marine ecosystems with unprecedented ecological and economic consequences. Climate change will include the simultaneous increase of temperature and CO 2 concentration in oceans. However, experimental manipulations of these factors at the community scale are rare. In this...

Phytoplankton primary production and its distribution amongst different size classes play a critical role in the functioning of pelagic marine ecosystems both from an ecological and biogeochemical point of view. Around a quarter of global marine primary production occurs in tropical and subtropical latitudes of the world’s oceans. Current knowledge...

Four surveys (Jun'06 and Nov'06; Feb'07 and May'07) were carried out on the northeastern shelf of the Gulf of Cadiz (southwest Iberian Peninsula) to relate the spatio-temporal distribution of the carbon cycle parameters (dissolved inorganic carbon and dissolved organic carbon) to picophytoplankton biomass and community composition. In addition, the...

Phytoplankton size structure is key for the ecology and biogeochemistry of pelagic ecosystems, but the relationship between cell size and maximum growth rate (μ(max) ) is not yet well understood. We used cultures of 22 species of marine phytoplankton from five phyla, ranging from 0.1 to 10(6) μm(3) in cell volume (V(cell) ), to determine experiment...

The relationship of photosynthesis (14C incorporation) to ultraviolet (UVR) and photosynthetically active radiation (PAR) was measured over the course of the late-spring to early-summer phytoplankton bloom in the Ross Sea Polynya (Southern Ocean). Experiments were conducted in November 2005 to determine PAR-only photosynthesis-irradiance (P-E) curv...

Experimental results related to the effects of ocean acidification on planktonic marine microbes are still rather inconsistent and occasionally contradictory. Moreover, laboratory or field experiments that address the effects of changes in CO2 concentrations on heterotrophic microbes are very scarce, despite the major role of these organisms in the...

Detailed studies were made in the springtime Ross Sea Polynya of the interaction between near-surface mixing processes, inferred from Thorpe scales and acoustic backscatter, and the quantum efficiency and rate of PSII electron transport of phytoplankton photosynthesis measured at fine depth and time scales by active fluorometry. The phytoplankton a...

UVR exposure is known to cause developmental defects in a variety of organisms including aquatic species but little is known about the underlying molecular mechanisms. In this work we used zebrafish (Danio rerio) embryos as a model system to characterize the UVR effects on fish species. Larval viability was measured for embryos exposed to several U...

Experimental results related to the effects of ocean acidification on planktonic marine microbes are still rather inconsistent and occasionally contradictory. Moreover, laboratory or field experiments that address the effects of changes in CO2 concentrations on heterotrophic microbes are very scarce, despite the major role of these organisms in the...

Este estudio muestra los resultados de abundancia y biomasa de poblaciones naturales costeras de microfitoplancton y nanoplacton aireadas con concentraciones actuales de CO2 atmosférico (380 ppmv CO2) y con concentraciones esperadas para futuros escenarios de cambio climático (1000 ppmv CO2). Las poblaciones fueron incubadas en los meses de Junio y...

This study tests the effects of elevated CO2 and ultraviolet radiation (UVR) on phytoplankton photosynthesis through in situ incubations in Lake Giles, Pennsylvania. In a first experiment, CO2 was supplied from a tank to simulate atmospheric CO2 concentrations predicted in scenarios of future global change. In a second experiment, elevated CO 2 con...

It is well known that UV radiation can cause deleterious effects to the physiological performance, growth and species assemblages of marine primary producers. In this review we describe the range of interactions observed between these impacts of ultraviolet radiation (UVR, 280-400 nm) with other environmental factors such as the availability of pho...

Background: Human activities have increased atmospheric concentrations of carbon dioxide by 36% during the past 200 years. One third of all anthropogenic CO(2) has been absorbed by the oceans, reducing pH by about 0.1 of a unit and significantly altering their carbonate chemistry. There is widespread concern that these changes are altering marine...

We studied the effects of elevated CO2 concentrations (0.03% vs. 0.1%) on light absorption, membrane permeability, growth, and carbon fixation under photosynthetically active radiation (PAR) and ultraviolet radiation (UVR) exposures in the diatom Thalassiosira pseudonana. Susceptibility of photosynthesis to UVR was estimated using biological weight...

Previous studies in the Guadiana upper estuary showed a relationship between nutrient ratios and phytoplankton succession, which involved a diatom spring bloom followed by cyanobacteria dominance during summer. Silica depletion was thought to be the trigger of cyanobacteria summer blooms. The recently constructed Alqueva dam is expected to affect n...

Temperature is expected to modify the effects of ultraviolet radiation (UVR) on photosynthesis by affecting the rate of repair. We studied the effect of short-term (1 h) and long-term (days) acclimation to temperature on UVR photoinhibition in the diatom Thalassiosira pseudonana Hasle et Heimdal. Photosynthesis was measured during 1 h exposures to...

The effect of ultraviolet radiation (UVR) on inhibition of photosynthesis was studied in two species of marine picoplankton with different carbon concentration mechanisms: Nannochloropsis gaditana Lubian possesses a bicarbonate uptake system and Nannochloris atomus Butcher a CO2 active transport system. Biological weighting functions (BWFs) for inh...

Specimens from the eastern Atlantic, Mediterranean and Adriatic seas previously reported as Botryocladia chiajeana showed differences in morphology, and re-examination of Meneghini's original collection of Chrysymenia chiajeana (basionym B. chiajeana) revealed that only the Mediterranean and Adriatic specimens are in agreement with the original pro...

Bacterial abundances determined in Drake Passage and Bransfield and Gerlache Straits (Antarctica) in the Austral summer ranged from 0.78 to 9.4105 cells ml−1, and were positively correlated with standing stocks of Chl a. Two bacterial subpopulations were discriminated based in their different levels of green fluorescence and wide angle light scatte...

The light-induced de-epoxidation of xanthophylls is an important photoprotective mechanism in plants and algae. Exposure to ultraviolet radiation (UVR, 280–400 nm) can change the extent of xanthophyll de-epoxidation, but different types of responses have been reported. The de-epoxidation of violaxanthin (V) to zeaxanthin (Z), via the intermediate a...

The aim of this study was to assess the effect of UV-A (320 to 400 nm) and UV-B (280 to 320 nm) radiation on diel patterns of growth and metabolic activity of the marine picoplankter Nannochloris atomus using flow cytometry. N, atomus cells exposed to PAR (400 to 700 nm), PAR+UV-A and PAR+UV-A+UV-B showed clear diel patterns in cell size, chlorophy...

This study shows the response of Nannochloropsis gaditana, a marine nannoplanktonic species, exposed to UV radiation for 7 days. PAR, UV-A and UV-B ratios used were within the range likely to be observed in nature, a photoperiod of 12L:12D was maintained, and light irradiances were modified daily to promote cell acclimation. Growth, pigment content...

ABSTRACT Blooms of toxic cyanobacteria develop regularly during summer,and early,autumn,in the Guadiana River (South of Iberian Peninsula). Microcystis aeruginosa, Aphanizomenon flos-aquae, Oscillatoria spp. and Anabaena spp. have been identified in previous studies as the main toxic cyanobacteria present. With the closure of the Alqueva dam and it...

The morphology of the western Atlantic Botryocladia shanksii E. Y. Dawson and B. pyriformis (Børgesen) Kylin are examined in material collected in the Canary Islands, confirming the amphi-Atlantic distribution of both species. Botryocladia shanksii, which was found growing in the lower eulittoral, is reported for the first time in the eastern Atlan...

The type species of Botryocladia, B. botryoides, and B. occidentalis and B. canariensis Afonso-Carrillo & Sobrino sp. nov., are described in detail from material collected in the Canary Islands. The previously incomplete and partially ambiguous information about the vegetative and reproductive morphology of B. botryoides is completed and clarified....