Assessing the carbon footprint of the 15th International Coral Reef Symposium (ICRS) in Bremen, Germany.

International scientific conferences serve as vital platforms for networking, knowledge exchange, and collaborative responses to global challenges. To exemplify sustainable practices, it is essential to organize these events in a climate-friendly manner, particularly for topics directly tied to environmental conservation, such as coral reef research. The 15th International Coral Reef Symposium (ICRS), held in Bremen, Germany, in July 2022, aimed to minimize its environmental impact through a comprehensive green strategy.

Future of coral bleaching research.

Coral bleaching is the largest global threat to coral reef ecosystem persistence this century. Advancing our understanding of coral bleaching and developing solutions to protect corals and the reefs they support are critical. In the present article, we, the US National Science Foundation-funded Coral Bleaching Research Coordination Network, outline future directions for coral bleaching research.

Effects of three sunscreens on the ecophysiology of hard and soft corals from the Maldives.

Local pollution with cosmetic products, particularly from tourism-related activities, can threaten coral reefs. The potential negative effects of sunscreens on corals caused several countries to ban certain sunscreens or ingredients. Many companies advertise their sunscreens as "reef-safe" or "coral-friendly", but scientific analysis is necessary to verify these claims.

Probiotics prevent mortality of thermal-sensitive corals exposed to short-term heat stress.

The use of coral probiotics, i.e. beneficial microorganisms for corals (BMCs), is a novel approach to enhancing coral health under heat stress.

Temperature-dependent responses of the hard corals Acropora sp. and Pocillopora verrucosa to molecular hydrogen.

Coral reefs are increasingly threatened by mass bleaching events due to global ocean warming. Novel management strategies are urgently needed to support coral survival until global efforts can mitigate ocean warming. Given the strong antioxidant, anti-inflammatory and anti-apoptotic properties of molecular hydrogen, our study explores its potential to alleviate the negative effects of heat stress on corals.

Coral high molecular weight carbohydrates support opportunistic microbes in bacterioplankton from an algae-dominated reef.

Unlabelled: High molecular weight (HMW; >1 kDa) carbohydrates are a major component of dissolved organic matter (DOM) released by benthic primary producers. Despite shifts from coral to algae dominance on many reefs, little is known about the effects of exuded carbohydrates on bacterioplankton communities in reef waters. We compared the monosaccharide composition of HMW carbohydrates exuded by hard corals and brown macroalgae and investigated the response of the bacterioplankton community of an algae-dominated Caribbean reef to the respective HMW fractions.

Swirls and scoops: Ice base melt revealed by multibeam imagery of an Antarctic ice shelf.

Knowledge gaps about how the ocean melts Antarctica's ice shelves, borne from a lack of observations, lead to large uncertainties in sea level predictions. Using high-resolution maps of the underside of Dotson Ice Shelf, West Antarctica, we reveal the imprint that ice shelf basal melting leaves on the ice. Convection and intermittent warm water intrusions form widespread terraced features through slow melting in quiescent areas, while shear-driven turbulence rapidly melts smooth, eroded topographies in outflow areas, as well as enigmatic teardrop-shaped indentations that result from boundary-layer flow rotation.

Mucus carbohydrate composition correlates with scleractinian coral phylogeny.

The mucus surface layer serves vital functions for scleractinian corals and consists mainly of carbohydrates. Its carbohydrate composition has been suggested to be influenced by environmental conditions (e.g.

Accelerated nitrogen cycling on Mediterranean seagrass leaves at volcanic CO vents.

Seagrass meadows form highly productive and diverse ecosystems in coastal areas worldwide, where they are increasingly exposed to ocean acidification (OA). Efficient nitrogen (N) cycling and uptake are essential to maintain plant productivity, but the effects of OA on N transformations in these systems are poorly understood. Here we show that complete N cycling occurs on leaves of the Mediterranean seagrass Posidonia oceanica at a volcanic CO vent near Ischia Island (Italy), with OA affecting both N gain and loss while the epiphytic microbial community structure remains largely unaffected.

Recent and rapid reef recovery around Koh Phangan Island, Gulf of Thailand, driven by plate-like hard corals.

Mass bleaching events and local anthropogenic influences have changed the benthic communities of many coral reefs with pronounced spatial differences that are linked to resilience patterns. The Gulf of Thailand is an under-investigated region with only few existing datasets containing long-term developments of coral reef communities using the same method at fixed sites. We thus analyzed benthic community data from seven reefs surrounding the island of Koh Phangan collected between 2014 and 2022.

Short-term ocean acidification decreases pulsation and growth of the widespread soft coral Xenia umbellata.

Coral reefs may experience lower pH values as a result of ocean acidification (OA), which has negative consequences, particularly for calcifying organisms. Thus far, the effects of this global factor have been mainly investigated on hard corals, while the effects on soft corals remain relatively understudied. We therefore carried out a manipulative aquarium experiment for 21 days to study the response of the widespread pulsating soft coral Xenia umbellata to simulated OA conditions.

Presence of algal symbionts affects denitrifying bacterial communities in the sea anemone Aiptasia coral model.

The coral-algal symbiosis is maintained by a constant and limited nitrogen availability in the holobiont. Denitrifiers, i.e.

Excess labile carbon promotes diazotroph abundance in heat-stressed octocorals.

Nitrogen limitation is the foundation of stable coral-algal symbioses. Diazotrophs, prokaryotes capable of fixing N into ammonia, support the productivity of corals in oligotrophic waters, but could contribute to the destabilization of holobiont functioning when overstimulated. Recent studies on reef-building corals have shown that labile dissolved organic carbon (DOC) enrichment or heat stress increases diazotroph abundance and activity, thereby increasing nitrogen availability and destabilizing the coral-algal symbiosis.

Individual and combined effect of organic eutrophication (DOC) and ocean warming on the ecophysiology of the Octocoral .

Dissolved organic carbon (DOC) enrichment and ocean warming both negatively affect hard corals, but studies on their combined effects on other reef organisms are scarce. Octocorals are likely to become key players in future reef communities, but they are still highly under-investigated with regard to their responses to global and local environmental changes. Thus, we evaluated the individual and combined effects of DOC enrichment (10, 20 and 40 mg L DOC, added as glucose) and warming (stepwise from 26 to 32 °C) on the widespread Indo-Pacific gorgonian in a 45-day laboratory experiment.

Temperature, species identity and morphological traits predict carbonate excretion and mineralogy in tropical reef fishes.

Anthropogenic pressures are restructuring coral reefs globally. Sound predictions of the expected changes in key reef functions require adequate knowledge of their drivers. Here we investigate the determinants of a poorly-studied yet relevant biogeochemical function sustained by marine bony fishes: the excretion of intestinal carbonates.

Spatiotemporal variability of oxygen concentration in coral reefs of Gorgona Island (Eastern Tropical Pacific) and its effect on the coral .

Dissolved oxygen concentration (DO) is one of the main factors limiting benthic species distribution. Due to ocean warming and eutrophication, the ocean is deoxygenating. In the Eastern Tropical Pacific (ETP), deep waters with low DO (<1 mg L) may reach coral reefs, because upwelling will likely intensify due to climate change.

The widely distributed soft coral Xenia umbellata exhibits high resistance against phosphate enrichment and temperature increase.

Both global and local factors affect coral reefs worldwide, sometimes simultaneously. An interplay of these factors can lead to phase shifts from hard coral dominance to algae or other invertebrates, particularly soft corals. However, most studies have targeted the effects of single factors, leaving pronounced knowledge gaps regarding the effects of combined factors on soft corals.

Ocean variability beneath Thwaites Eastern Ice Shelf driven by the Pine Island Bay Gyre strength.

West Antarctic ice-shelf thinning is primarily caused by ocean-driven basal melting. Here we assess ocean variability below Thwaites Eastern Ice Shelf (TEIS) and reveal the importance of local ocean circulation and sea-ice. Measurements obtained from two sub-ice-shelf moorings, spanning January 2020 to March 2021, show warming of the ice-shelf cavity and an increase in meltwater fraction of the upper sub-ice layer.

The pulsating soft coral Xenia umbellata shows high resistance to warming when nitrate concentrations are low.

The resistance of hard corals to warming can be negatively affected by nitrate eutrophication, but related knowledge for soft corals is scarce. We thus investigated the ecophysiological response of the pulsating soft coral Xenia umbellata to different levels of nitrate eutrophication (control = 0.6, medium = 6, high = 37 μM nitrate) in a laboratory experiment, with additional warming (27.

Fleshy red algae mats act as temporary reservoirs for sessile invertebrate biodiversity.

Many coastal ecosystems, such as coral reefs and seagrass meadows, currently experience overgrowth by fleshy algae due to the interplay of local and global stressors. This is usually accompanied by strong decreases in habitat complexity and biodiversity. Recently, persistent, mat-forming fleshy red algae, previously described for the Black Sea and several Atlantic locations, have also been observed in the Mediterranean.

Surface flow for colonial integration in reef-building corals.

Reef-building corals are endangered animals with a complex colonial organization. Physiological mechanisms connecting multiple polyps and integrating them into a coral colony are still enigmatic. Using live imaging, particle tracking, and mathematical modeling, we reveal how corals connect individual polyps and form integrated polyp groups via species-specific, complex, and stable networks of currents at their surface.

The role of epiphytes in seagrass productivity under ocean acidification.

Ocean Acidification (OA), due to rising atmospheric CO, can affect the seagrass holobiont by changing the plant's ecophysiology and the composition and functioning of its epiphytic community. However, our knowledge of the role of epiphytes in the productivity of the seagrass holobiont in response to environmental changes is still very limited. CO vents off Ischia Island (Italy) naturally reduce seawater pH, allowing to investigate the adaptation of the seagrass Posidonia oceanica L.

Effective asexual reproduction of a widespread soft coral: comparative assessment of four different fragmentation methods.

Background: Many coral reefs worldwide are experiencing declines in hard corals, resulting in other benthic organisms, , soft corals, becoming more dominant. As such, more studies on the ecophysiology of soft corals are needed. Despite many methods for asexual reproduction of hard corals, effective methods for soft corals, .

Metazoan endoparasite fauna and feeding ecology of commercial fishes from Java, Indonesia.

Despite being an important component of the marine ecosystem and posing health risks to human seafood consumers, fish parasites in Indonesia have yet to be adequately described. Here, we analyzed the diet and metazoan parasite fauna of seven commercial fish species (Alectis indica, Carangoides chrysophrys, Johnius borneensis, Mene maculata, Trichiurus lepturus, Upeneus asymmetricus, U. moluccensis) landed in Java, Indonesia.