• Energy Research

AbstractIn 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 diatoms are unknown. Here we explored the changes in bacterial communities and heterotrophic production during the spring bloom in four consecutive spring blooms across several sub‐basins of the Baltic Sea and related them to changes in environmental variables and in phytoplankton community structure. The taxonomic structure of bacterioplankton assemblages was partially explained by salinity and temperature but also linked to the phytoplankton community. Higher carbon biomass of the diatoms Achnanthes taeniata, Skeletonema marinoi, Thalassiosira levanderi, and Chaetoceros spp. was associated with more diverse bacterial communities dominated by copiotrophic bacteria (Flavobacteriia, Gammaproteobacteria, and Betaproteobacteria) and higher bacterial production. During dinoflagellate dominance, bacterial production was low and bacterial communities were dominated by Alphaproteobacteria, mainly SAR11. Our results suggest that increases in dinoflagellate abundance during the spring bloom will largely affect the structuring and functioning of the associated bacterial communities. This could decrease pelagic remineralization of organic matter and possibly affect the bacterial grazers communities.

AbstractThe ratio of inorganic nitrogen to phosphorus (NP) is projected to decrease in the Eastern Boundary Upwelling Systems (EBUS) due to warming of the surface waters. In an enclosure experiment, we employed two levels of NP ratios (10 and 5) for three distinct plankton communities collected along the coast of central Chile (33°S). The primary effect of the NP treatment was related to different concentrations of NO3, which directly influenced the biomass of phytoplankton. Additionally, low inorganic NP ratio reduced the seston NP and Chla-C ratios, and there were some effects on the plankton community composition, e.g. benefittingSynechococcusspp in some communities. One of the communities was clearly top down controlled and trophic transfer to grazers was up to 5.8% during the 12 day experiment. Overall, the initial plankton community composition was more important for seston stoichiometry and trophic transfer than the inorganic NP ratio. Any long term change in the plankton community structure will likely have greater impact than direct effects of a decreasing inorganic NP ratio on the Humboldt Current ecosystem.

AbstractMacroalgae-based products are increasing in demand also in Europe. In the European Union, each category of macroalgae-based products is regulated separately. We discuss EU legislation, including the law on medicinal products, foods including food supplements and food additives, feed and feed additives, cosmetics, packaging materials, fertilizers and biostimulants, as well as biofuels. Product safety and consumer protection are the priorities with any new products. Macroalgae products can be sold as traditional herbal medicines. The novel food regulation applies to macroalgae foods that have not previously been used as food, and organic macroalgae are a specific regulatory category. The maximum levels of heavy metals may be a barrier for macroalgae foods, feeds, and fertilizers. Getting health claims approved for foods based on macroalgae is demanding. In addition to the rules on products, the macroalgae business is strongly impacted by the elements of the general regulatory environment such as agricultural/aquacultural subsidies, maritime spatial planning and aquaculture licensing, public procurement criteria, tax schemes, and trade agreements.

El objetivo principal de este estudio fue analizar el papel que llevan a cabo las cascadas de las proteínas tipo MAPKs en la transducción de señales de estrés ambiental en el organismo modelo D. viridis. Se detectó la activación/desactivación y la función de las proteínas tipo MAPKs en este microalga adaptada a condiciones de alta salinidad, ante condiciones de hipersalinidad, alta irradiancia y UV. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.