Abstract

The discharge of Fukushima radioactively contaminated water into the Pacific Ocean started in August 2023, posing comprehensive threats to marine ecosystems and human health globally. This study introduces the Fukushima Contaminated Water Risk Factor (FCWRF), which integrates three components─radionuclide diffusion, bioaccumulation, and global seafood trade─to evaluate the spatiotemporal distribution of risks based on actual discharge practices. Results suggest that comprehensive risks exceeding 2 orders of magnitude beyond the baseline will be transferred to six continents globally. Furthermore, the spread of such risks is projected to be six times faster than radionuclide diffusion. In the simulation, the results illustrated a small increase in radionuclide activity occurring in most regions of the Pacific Ocean. Nevertheless, the dimensionless FCWRF based on a novel integrated framework bridges the barriers among different fields in the risk assessment of radionuclides, thereby underpinning timely and effective responses from the global community.

cross-posted from: https://beehaw.org/post/18695339

A new study finds that even as mariculture expands globally, the industry could actually decrease its current biodiversity impact by 30%—if they get smarter about where they farm. But the same study also cautions that seafood farming in the wrong locations could just as easily ramp up current marine biodiversity impacts by over 400%.

One-fifth of the fish we consume is provided by farmed seafood, and that figure is only projected to rise as global demand for protein grows. The new research, published in Nature Ecology & Evolution, calculated that mariculture—the controlled production of shellfish, bivalves, and finfish in coastal areas and in the open ocean—will need to increase by 40.5% from 108,729 hectares to 152,785, to meet this growing demand by 2050.

Under a worst-case future scenario, where mariculture expansion occurred only in biodiversity-rich regions such as these, the effects could be profound: the cumulative biodiversity impact of seafood farming would increase by an average 270% at the country level, and by 420.5% at a global scale, compared to current impacts. Species-wise, the worst affected by mariculture under this extreme scenario would be large marine mammals including whales and seals, because these animals have considerable ranges that would overlap with more open-ocean farms.

But just as there’s a worst-case scenario, the researchers also posit a best-case scenario—one we could achieve, they say, if we take a more strategic approach.

“The best case scenario refers to all mariculture farms in 2050 [being] placed in sea areas with low [impact], including relocating existing farms and the new farms,” says Deqiang Ma, postdoctoral researcher at the University of Michigan School for Environment and Sustainability, and lead author in the new study. The model showed that if farms of the future were almost exclusively sited away from biodiversity hubs, the cumulative effects of mariculture would be on average 27.5% lower at the country level compared to 2020. Taken at the global scale, that equaled an impact reduction of 30.5%. Under this best-case future scenario, almost all marine species considered in the study would experience lower impacts compared to the current-day harms of seafood farms.

The annual competition draws thousands of entries from across the world and brings together images from below the water’s surface that show the diversity and challenges of subaquatic life

Despite their distinction as one of Earth's oldest lifeforms and the key role they play in sustaining coral reef ecosystems, marine sponges are vastly understudied.

Sponges are notoriously difficult to study, for a variety of reasons.

I’m campaigning for legal protection for cleaner fish, because no one has done a proper assessment of the impact of removing them from Scottish reefs

Exceptionally warm global waters will not disappear. However, we can avoid the worst impacts of climate change and even hotter water temperatures by taking rapid action to strengthen local, state, and national climate policy initiatives.

A new study finds that the rate of ocean warming has more than quadrupled over the past 40 years — and pinpoints why.

Biologist says the massive numbers of jellyfish and algae in Tasmania’s Storm Bay are ‘drivers of harm in the ocean’

She said filming the Aurelia aurita – moon jellyfish – swimming through bioluminescent organisms on Thursday was “the most magical thing I’ve seen in my life”, but also a sign of something wrong.

Shallow coastal waters are hotspots for methane emissions, releasing significant amounts of this potent greenhouse gas into the atmosphere and contributing to global warming. New research highlights how tides, seasons, and ocean currents strongly influence methane emissions and how tiny microorganisms, called methanotrophs, help reduce their impact. These findings are part of a dissertation by NIOZ Ph.D. candidate Tim de Groot, which he will defend on January 31, 2025 at Utrecht University.

More, here: https://www.sciencedaily.com/releases/2025/01/250123163516.htm

In the sea as on land, climate change is driving shifts in the abundance and distribution of species. Scientists are just beginning to focus on why some fish predators and prey — like striped bass and menhaden on the U.S. East Coast — are changing their behavior as waters warm.

Kochi: The fisher community will intensify its strong protests against the deep-sea mining proposed by Centre off the Kerala coasts.

In a landmark ruling, Ecuador’s Constitutional Court concluded that the government must set limits on human activity, like industrial fishing, to protect marine ecosystems’ natural cycles.

Ecuador, in 2008, became the first country in the world to recognize in a national constitution that nature, similar to humans and corporations, has legal rights. More than a dozen other countries have through legislation or court rulings recognized that ecosystems or individual species have rights, including to live, persist and regenerate.

Until now, all of Ecuador’s Constitutional Court rulings regarding nature’s rights have involved ecosystems on land, mangroves and wild animals. Lawyers familiar with rights of nature jurisprudence say the coastal marine ecosystem case, released late last year, is a landmark decision that extends heightened protections to the country’s vast aquatic ecosystems.

Research on Scott Reef off Northwest Australia has shown that local coral connections help boost the resilience of remote atoll reef systems following bleaching and storms.

The research, based on extensive modeling of currents and other oceanographic variables, (...)

The study, reported in a paper published in the journal Limnology and Oceanography, investigated the Scott system of reefs, an isolated group of three coral atolls 300 km off the northwest coast of Australia.