Although covering only ~0.2% of the ocean’s surface, coral reefs harbour ~25% of ocean biodiversity and provide food to nearly a billion people. Ecological services from coral reefs are essential through fisheries, tourism, coastal protection and are estimated at about 30 billions USD per year. But corals are being stressed and recent estimates indicate that ~20% of reefs have permanently disappeared and about 50% will be threatened by 2050. Coral reefs are often at the forefront of research on climate change, due to bleaching, ocean acidification, and concerns about reef growth processes. Recent genomic developments have demonstrated the complexity of the coral genome that appears as complex as that for vertebrates. Reef corals further add to this complexity through an obligatory photo-endosymbiosis developed with microalgae. The physiological consequences of the presence of these photosynthetic microalgae (called zooxanthellae), which further add to the complexity of the coral hologenome, and the deep physio-genomic impacts resulting from this symbiosis on both partners, have yet to be fully elucidated. Furthermore, corals are hosts of a still largely unknown world of associated bacteria, viruses and other protists, forming a complex symbiocosm that biologists refer to as ‘holobiont’. This project entitled, “Genomic complexity of the coral holobiont across biodiversity gradients in the Pacific” is ambitious and seeks to investigate the complex diversity of the coral holobiont within the context of global change. It will serve as the foundation for the new Tara Pacific expedition (2016-2018). It builds upon the experience of previous Tara-Oceans expeditions and will focus on coral reefs throughout the Pacific Ocean, drawing an east-west transect from Panama to Japan and a south-north transect from New Zealand to Japan, and will sample corals throughout roughly 35 island systems with local replicates. CORALGENE will develop and apply state-of-the-art technologies in very-high-throughput genetic sequencing to reveal the entire microbial diversity (i.e. full biological complexity) present within coral holobionts. CORALGENE brings together a consortium of international experts in marine biology and ecology, cellular and molecular biology, genomics, and bioinformatics. Though this diverse team of global coral reef experts, we will have the expertise needed to build a comprehensive morpho-molecular inventory of the biodiversity of the coral holobiont, from viruses to prokaryotes, unicellular eukaryotes, and metazoans, which will include the biodiversity from both interstitial and surrounding seawaters. This very ambitious project will reveal a massive amount of cryptic and novel biodiversity, will shed light on the complex links between genomes, transcriptomes, metabolomes, organisms, and ecosystem functions in coral reefs, and will provide a reference of the biological state of modern coral reefs for the large research community working on coral adaptation to global and regional stressors.

The mesopelagic layer is one of the least understood ecosystems on Earth. Recent research suggests that the fish biomass in the mesopelagic ecosystem might be 10 times higher than previously thought, and therefore represent 90 % of the fish biomass of the planet. However, this estimate is subject to a high degree of uncertainty in the fraction of the community that is fish. The potential high biomass has raised interest in its exploitation, mainly as a fish meal, but other potential exploitation pathways for high value compounds, such as nutraceuticals and pharmaceuticals, are possible. Nevertheless, if the biomass is as high as estimated, mesopelagic fish may play a key role in ecosystem services, such as sustaining other commercially relevant species and carbon sequestration. SUMMER will establish a protocol to accurately estimate mesopelagic fish biomass, quantify the ecosystem services provided by the mesopelagic community (food, climate regulation and potential for bioactive compounds) and develop a decision support tool to measure the trade-offs between the different services. Combining eDNA with in situ acoustics and trawls SUMMER will obtain an accurate assessment of the composition and biomass of the mesopelagic community. Gut content analysis, molecular markers and stable isotopes will allow quantification of the vertically integrated trophic network, linking to commercial and charismatic species. Models will be used to estimate the impact of fishing scenarios on trophic network stability and carbon sequestration. Mesopelagic organisms will be tested for their potential as fish meal, nutra and pharmaceuticals. The project will develop a decision support tool to enable accounting for trade-offs between services in when considering sustainable use of mesopelagic resources. Finally, a range of interactions with stakeholders, policy makers and public will ensure that any strategy to exploit the mesopelagic ecosystem takes account of all the consequences.

Combustion instabilities constitute a severe challenge in the development of efficient low-emission combustion systems, such as gas turbines for aeronautical and power generation applications. Previous work has shown the principle capability of nanosecond repetitively pulsed (NRP) plasma discharges to mitigate this undesirable unsteady combustion phenomenon in academic configurations; however, essential physical effects associated with the application of this technology in real gas turbine engines for aircraft propulsion and power generation have not been considered yet. These effects are related to 1.) liquid-fueled spray flames, 2.) elevated operating pressure, and 3.) high-frequency non-planar modes. The GECCO project will tackle these three aspects with dedicated experiments and high fidelity simulations. A common swirl-burner platform will be used for all three aspects to maximize synergy effects between the individual work packages. The AVBP code, well established for turbulent combustion simulations of academic and industrial configurations, will be combined to a plasma code to account for the effects of NRP plasma discharges on turbulent flames, taking into account ultrafast heating as well as slower thermal and chemical effects. Once validated on the basis of experimental data, this numerical tool will be essential in achieving a comprehensive understanding of the plasma-flame-acoustic interaction related to the 3 effects mentioned above. The effect of NRP discharges on the dynamics of spray flames will be assessed in detailed measurements (phase-Doppler anemometry, light-sheet tomography, particle image velocimetry), investigating the influence on the cold spray, the flame shape, and the dynamic response to acoustic perturbations (flame transfer function, FTF). To assess and demonstrate the potential of NRP discharges in the mitigation of high-frequency azimuthal instabilities, the swirl burner will be equipped with circumferentially distributed plasma actuation. The response of the flame to this type of forcing will be experimentally assessed using azimuthally resolved measurements (pressure, chemiluminescence). Plasma-flame-acoustic interaction at elevated pressures will be investigated in a high-pressure facility. The effect of NRP on the FTF and the response of the flame to low-frequency modulated harmonic plasma forcing will be measured up to 10 bar. All experimental tasks are accompanied by corresponding simulations that will provide a more detailed understanding of the interaction mechanisms than accessible by measurements only. In the final part of the project, NRP discharge forcing will be utilized to control acoustically coupled combustion oscillations in the three experimental facilities (spray flames, high-frequency modes, elevated pressure). GECCO may, thus, increase the fundamental understanding of dynamic plasma flame interaction and, on the other hand, bring this technology significantly closer to real applications.