Metataxonomy and pigments analyses unravel microbial diversity and the relevance of retinal-based photoheterotrophy at different salinities in the Odiel Salterns (SW, Spain).

Salinity has a strong influence on microorganisms distribution patterns and consequently on the relevance of photoheterotrophic metabolism, which since the discovery of proteorhodopsins is considered the main contributor to solar energy capture on the surface of the oceans. Solar salterns constitute an exceptional system for the simultaneous study of several salt concentrations, ranging from seawater, the most abundant environment on Earth, to saturated brine, one of the most extreme, which has been scarcely studied. In this study, pigment composition across the salinity gradient has been analyzed by spectrophotometry and RP-HPLC, and the influence of salinity on microbial diversity of the three domains of life has been evaluated by a metataxonomic study targeting hypervariable regions of 16S and 18S rRNA genes.

Accumulation, biochemical responses and changes in the redox proteome promoted by Ag and Cd in the burrowing bivalve Scrobicularia plana.

Silver (Ag) and cadmium (Cd) are non-essential metals that, as a result of natural processes and human activities, reach the aquatic environment where they interact with biota inducing potential toxic effects. To determine the biological effects of these metals on the endobenthic bivalve Scrobicularia plana, specimens were exposed to Ag and Cd at two concentrations, 5 and 50 μg∙L, for 7 days in a controlled microcosm system. The levels of the metals were measured in the seawater, sediments and clam tissues.

Structural and functional alterations under stress conditions by contamination: A multi-species study in a non-forced multi-compartmented mesocosm.

Despite the existing connectivity and heterogeneity of aquatic habitats, the concept of interconnected landscapes has been frequently overlooked in ecotoxicological risk assessment studies. In this study, a novel mesocosm system, the HeMHAS (Heterogeneous Multi-Habitat Assay System), was constructed with the potential to assess structural and functional changes in a community resulting from exposure to contaminants, while also considering the complex ecological scenarios. Fish (Sparus aurata), shrimp (Palaemon varians) and three species of marine microalgae (Isochrysis galbana, Nannochloropsis gaditana and Tetraselmis chuii) were used as test organisms.

Ions and nanoparticles of Ag and/or Cd metals in a model aquatic microcosm: Effects on the abundance, diversity and functionality of the sediment bacteriome.

Metals can be adsorbed on particulate matter, settle in sediments and cause alterations in aquatic environments. This study assesses the effect of Ag and/or Cd, both in ionic and nanoparticle (NP) forms, on the microbiome of sediments. For that purpose, aquatic controlled-microcosm experiments were exposed to an environmentally relevant and at tenfold higher doses of each form of the metals.

Evaluation of short-term copper toxicity in a co-culture of Synechococcus sp., Chaetoceros gracilis and Pleurochrisys cf. roscoffensis exposed to changes in temperature and salinity levels.

Metals such as copper (Cu) enter marine environments from natural and anthropogenic sources, causing changes in the biodiversity of marine microalgae and cyanobacteria. Cu plays a dual role as either a micronutrient or toxicant depending on the environmental concentration. Many studies have summarized the potential of Cu to become more toxic to microalgae under environmental stress (for instance climate change).

Population and functional changes in a multispecies co-culture of marine microalgae and cyanobacteria under a combination of different salinity and temperature levels.

Changes in the temperature or salinity of ocean waters can affect marine organisms at multiple trophic levels. Both environmental variables could have an impact on marine microalgae populations. Therefore, the effect of the combination of three levels of temperature (20, 24 and 28 °C), and three levels of salinity (33, 36, and 39 PSU) were evaluated on the growth of a multispecies community of five common species of phytoplankton: (one cyanobacteria, Synechococcus sp.

Single and multispecies microalgae toxicological tests assessing the impact of several BPA analogues used by industry.

BPA is a hazard for human and environmental health and recently BPA was added to the Candidate List of substances of very high concern by European Chemical Agency (ECHA). In accordance with this proposal, the authorities have encouraged the replacement of BPA by BPA analogues; however, little is known about the impact of these compounds on the environment. Due to this situation five BPA analogues (BPS, BPAP, BPAF, BPFL and BPC) were chosen in order to study their effects on marine primary producers.

Influence of salinity and temperature on the growth, productivity, photosynthetic activity and intracellular ROS of two marine microalgae and cyanobacteria [Mar. Environ. Res. 2023 Apr; 186:105932. Epub 2023 Feb 24].

Global Climate Change could change physical parameters in oceans, such as salinity and temperature. The impact of such changes in phytoplankton has not been well stated yet. In this study the effect of combination of three levels of temperature (20, 23, and 26 °C), and three levels of salinity (33, 36, and 39) on growth of a mixture co-cultivation of three common species from phytoplankton (one cyanobacteria, Synechococcus sp.

Corrigendum to "Influence of salinity and temperature on the growth, productivity, photosynthetic activity and intracellular ROS of two marine microalgae and cyanobacteria" [Mar. Environ. Res. 186 (2023) 105932].

Global Climate Change (GCC) could change physical parameters in oceans, such as salinity and temperature. The impact of such changes in phytoplankton has not been well stated yet. In this study, the effect of combination of three levels of temperature (20, 23, and 26 °C) and three levels of salinity (33, 36, and 39) on growth of a mixture co-cultivation of three common species from phytoplankton (one cyanobacteria, Synechococcus sp.

Evaluation of algaecide effectiveness of five different oxidants applied on harmful phytoplankton.

Harmful algal blooms (HABs) in coastal areas similarly impact both ecosystems and human health. The translocation of phytoplankton species via maritime transport can potentially promote the growth of HABs in coastal systems. Accordingly, ballast water must be disinfected.

Influence of salinity and temperature on the growth, productivity, photosynthetic activity and intracellular ROS of two marine microalgae and cyanobacteria.

Global Climate Change could change physical parameters in oceans, such as salinity and temperature. The impact of such changes in phytoplankton has not been well stated yet. In this study the effect of combination of three levels of temperature (20, 23, and 26 °C), and three levels of salinity (33, 36, and 39) on growth of a mixture co-cultivation of three common species from phytoplankton (one cyanobacteria, Synechococcus sp.

Effects of global environmental change on microalgal photosynthesis, growth and their distribution.

Global climate change (GCC) constitutes a complex challenge posing a serious threat to biodiversity and ecosystems in the next decades. There are several recent studies dealing with the potential effect of increased temperature, decrease of pH or shifts in salinity, as well as cascading events of GCC and their impact on human-environment systems. Microalgae as primary producers are a sensitive compartment of the marine ecosystems to all those changes.

Could Contamination Avoidance Be an Endpoint That Protects the Environment? An Overview on How Species Respond to Copper, Glyphosate, and Silver Nanoparticles.

The use of non-forced multi-compartmented exposure systems has gained importance in the assessment of the contamination-driven spatial avoidance response. This new paradigm of exposure makes it possible to assess how contaminants fragment habitats, interfering in the spatial distribution and species' habitat selection processes. In this approach, organisms are exposed to a chemically heterogeneous scenario (a gradient or patches of contamination) and the response is focused on identifying the contamination levels considered aversive for organisms.

Evaluation of three photosynthetic species smaller than ten microns as possible standard test organisms of ultraviolet-based ballast water treatment.

The Ballast Water Management Convention (BWMC) establishes limits for viable organisms in discharged ballast water. However, organisms smaller than 10 μm are not considered in this regulation although they represent, in some regions, the majority of the phytoplankton organisms in marine water. The objective in this study is to assess three photosynthetic species smaller than 10 μm as potential standard test organism (STO) in experimentation focused on the inactivating efficacy of ultraviolet treatments (UV).

Not Only Toxic but Repellent: What Can Organisms' Responses Tell Us about Contamination and What Are the Ecological Consequences When They Flee from an Environment?

The ability of aquatic organisms to sense the surrounding environment chemically and interpret such signals correctly is crucial for their ecological niche and survival. Although it is an oversimplification of the ecological interactions, we could consider that a significant part of the decisions taken by organisms are, to some extent, chemically driven. Accordingly, chemical contamination might interfere in the way organisms behave and interact with the environment.

Improving the microalgae inactivating efficacy of ultraviolet ballast water treatment in combination with hydrogen peroxide or peroxymonosulfate salt.

Due to the increasing number of ecosystem invasions with the introduction of exogenous species via ballast water, the International Maritime Organization adopted the Ballast Water Convention (BWMC). The BWMC establishes standards for the concentration of viable organisms in a ballast water discharge. Ultraviolet (UV) irradiation is commonly used for treating ballast water; however, regrowth after UV irradiation and other drawbacks have been reported.

Effect of the length of dark storage following ultraviolet irradiation of Tetraselmis suecica and its implications for ballast water management.

Meeting the recent biological standards established by the Ballast Water Management Convention requires the application of ballast water treatment systems; ultraviolet irradiation is a frequently used option. However, organisms can repair the damage caused by ultraviolet irradiation primarily with photo-repair mechanisms that are dependent on the availability of light. The objective of this study is to quantify the impact of dark storage following ultraviolet irradiation on the viability of the microalgae Tetraselmis suecica.

Ingestion and bioaccumulation of polystyrene nanoplastics and their effects on the microalgal feeding of Artemia franciscana.

Nanoplastics (NPs) have become one of the most serious environmental problems nowadays. The environmental issues linked to NPs are attributed to the effects after ingestion in marine organisms. Due to the incipient and controversial information about the effects of PS NPs on the feeding of organisms, the aim of this work is to assess (i) digestion dynamics of Artemia franciscana when exposed to PS NPs as the lowest concentration of PS NPs reported in toxicity test [0 (control), 0.

Are the primary characteristics of polystyrene nanoplastics responsible for toxicity and ad/absorption in the marine diatom Phaeodactylum tricornutum?

Nowadays, the occurrence of a large volume of plastic litter in oceanic and coastal zones has increased concern about its impacts on marine organisms. The degradation of plastic polymers leads to the formation of smaller fragments at both micro and nano scale (<5 mm and <1 μm respectively). Nanoplastics (NPs), due to their smaller size and high specific surface area can establish colloidal interactions with marine microalgae, therefore potential toxicity can be led.

Erythromycin sensitivity across different taxa of marine phytoplankton. A novel approach to sensitivity of microalgae and the evolutionary history of the 23S gene.

Erythromycin has been recorded in coastal waters and could pose a severe threat to marine microbial life. Macrolides such as erythromycin may affect microalgae by inhibiting the pathways involved in protein synthesis. Toxicological testing of microalgae has proven to be a useful tool for the risk assessment of a substance affecting phytoplankton.

Effect of erythromycin and modulating effect of CeO NPs on the toxicity exerted by the antibiotic on the microalgae Chlamydomonas reinhardtii and Phaeodactylum tricornutum.

Erythromycin is an antibiotic employed in the treatment of infections caused by Gram positive microorganisms and the increasing use has made it a contaminant of emerging concern in aqueous ecosystems. Cerium oxide nanoparticles (CeO NPs), which are known to have catalytic and antioxidant properties, have also become contaminants of emerging concern. Due to the high reactivity of CeO NPs, they can interact with erythromycin magnifying their effects or on the other hand, considering the redox potential of CeO NPs, it can alleviate the toxicity of erythromycin.

Metal bioavailability in freshwater sediment samples and their influence on ecological status of river basins.

The general aim of this work has been to check the ecological impact of metals on the Ebro river basin. In order to evaluate this, metal behavior considering water, sediment as well as metal bioaccumulation in fish has been studied. Total concentrations of metals, as well as the potentially bioavailable fraction of metals in sediment has also been analyzed by the application of the sequential extraction method (BCR method).

Toxicity of silver and gold nanoparticles on marine microalgae.

The increased use of nanomaterials in several novel industrial applications during the last decade has led to a rise in concerns about the potential toxic effects of released engineered nanoparticles (NPs) into the environment, as their potential toxicity to aquatic organisms is just beginning to be recognised. Toxicity of metallic nanoparticles to aquatic organisms, including microalgae, seems to be related to their physical and chemical properties, as well as their behaviour in the aquatic media where processes of dissolution, aggregation and agglomeration can occur. Although the production of these particles has increased considerably in recent years, data on their toxicity on microalgae, especially those belonging to marine or estuarine environments remain scarce and scattered.

Is oxidative stress related to cadmium accumulation in the Mollusc Crassostrea angulata?

The kinetics of cadmium (Cd) accumulation in the gills and digestive gland of Crassotrea angulata at three concentrations of cadmium (0.088 μM, 0.44 μM and 2.

Assessment of sediment ecotoxicological status as a complementary tool for the evaluation of surface water quality: the Ebro river basin case study.

According to the European Water Framework Directive (WFD), assessment of surface water status is based on ecological and chemical status that is not always in coherence. In these situations, ecotoxicity tests could help to obtain a better characterization of the ecosystems. The general aim of this work is to design a methodology to study the ecotoxicological status of freshwater systems.