In the face of daunting challenges to our planet's coral reefs, a glimmer of hope emerges from Florida's coastal waters.
Scientists from Ohio State University discovered that the endangered elkhorn coral population in the Dry Tortugas National Park in Florida were highly resilient in its ability to adapt and thrive, despite adverse factors like climate change, pollution and disease outbreaks.
For more than two years, researchers on board the French expedition ship Tara sailed through the Pacific, stopping at almost 100 coral reefs to take thousands of water and coral samples. The expedition ended in 2018, and the analysis of the massive amount of data collected has taken five years.
Now, the initial results of the data analysis have been published. The findings should help us to better understand the living conditions of corals, to check their health status and to open up new possibilities for nature conservation.
Ocean deoxygenation has detrimental repercussions. Fish, crabs and other significant species of marine life that are unable to flee these low oxygen zones may perish as a result. People who depend on them for food and employment may be subsequently impacted by their absence as many of these species are economically significant.
Additionally, there is a negative feedback loop at play: as ocean oxygen levels decline, so does its capacity to absorb carbon dioxide. This may cause global warming to accelerate even further.
A study just published in Nature Communications suggests that the Atlantic Meridional Overturning Circulation (AMOC), of which the Gulf Stream is a part, could be approaching a tipping point. The AMOC, which has been gradually weakening over the last century and is reportedly at its weakest in over a millennium, could shift from its current strong mode to a weak one, with profound implications for the global climate.
Palau’s Rock Islands experience consistently higher temperatures and extreme heatwaves, yet their diverse coral communities bleach less than those on Palau’s cooler outer reefs.
Scientists studying reefs in Palau have identified genetic subgroups of a common coral species that exhibit remarkable tolerance to the extreme heat associated with marine heatwaves.
Who among us has not felt at least a twinge of guilt in booking a flight to a far-flung dive destination, knowing very well that the trip will add a significant contribution of CO2 and other greenhouse gases to the atmosphere? Being both a keen traveller and avid environmentalist, I surely have felt conflicted.
Species distribution models have become a valuable tool to predict the distribution of species across geographic space and time.
Model predictions revealed current areas of suitable habitat beyond the current northern range limits of the pink sea fan, in areas where colonies have not yet been observed.
"It's not clear why pink sea fans have not yet colonised these areas. Possible barriers include insufficient dispersal of their larvae and high competition between species for space and resources," said Dr Tom Jenkins, from the University of Exeter.
In the study, researchers reviewed some of the groundÂbreaking and recent coral-bleaching discoveries from an ecological, molecular and physiological viewpoint.
Seagrasses need nutrients to thrive, particularly nitrogen (N). Up to now, it has been assumed that the nitrogen is taken up by the seagrasses through leaves and roots from the surrounding seawater and sediment.
However, in many of the regions where seagrasses are most abundant, there is little nitrogen to be found. Furthermore, while nitrogen is abundant in the sea in its elemental form (N2), seagrasses cannot use it in this form.
Due to climate change, the average temperature in the Mediterranean Sea rises by one degree every thirty years, and this rate has been increasing. Because of this, the marine creatures there have been shifting their habitats to the deeper, cooler depths of the ocean.
Researchers reached this conclusion after reviewing research involving the depth distribution of 236 marine species like fish, crustaceans and mollusks collected in previous bottom-trawl surveys.
They discovered that the animals deepened their minimum depth limits in relation to rising sea temperatures.
