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Fishing, offshore wind energy, climate change and marine spatial planning: Is it possible to plan for a best use of space?
Full text linkThe significant expansion of offshore wind farms (OWF) is a core element of the world's decarbonisation strategy. However, in the urgency to meet Net Zero, care must be exercised to avoid exchanging one environmental crisis for another. A primary aim of this paper is to set out a methodology roadmap to ensure that future marine management and renewable energy policy is sustainable and evidence based. Marine ecosystems are complex, and the current lack of understanding makes it difficult to predict the effects of introducing thousands of wind turbines and extracting hundreds of gigawatts of wind energy that would have otherwise influenced our shelf seas ecosystems. It is difficult to predict the subsequent wider ecosystem effects of the combined changes in spatial use, such as displacement of fisheries out of OWF, along with possible attraction of fish into OWF developments.
Therefore, to proceed with any reasonable level of certainty, we need to be able to rapidly estimate the safe upper limit of whole ecosystem effects of OWF. As an example, this perspective paper sets out the challenges which OWF pose to fishing industries within the context of existing nature conservation policies. We propose modelling approaches that can incorporate both the ecological effects of large‐scale fisheries displacements as well as ecosystem level changes to fish populations from OWF developments. The ecosystem models can also predict the effects on future trends of fish populations within climate change forecasts.
Practical implication . To improve decision making when balancing environmental and socio‐economic benefits and trade‐offs, we then propose methods that use Marine Net Gain, which is a conservation approach that ensures human activities in marine environments result in a measurable net positive impact on biodiversity. The focus is on the United Kingdom and North Sea; however, the proposed roadmap holds the capability to be transferable to other shelf sea systems with similar types and levels of pressures. This perspective provides a methodology roadmap that considers the link between, and the need for, both food and energy security from our oceans and provides a route to increased certainty in our current choices for the long‐term sustainable use of our oceans
A Reproducible CO9p2 AMM7 NEMOv4.0.4 ERSEM Configuration
Full text linkThis document describes the setup for the Coastal Ocean
Atlantic Margin Model 7km model coupled with ERSEM
biogeochemistry. The domain covers the northwest European
shelf, reaching the coast of Portugal in the south, Iceland in the north-west and the Skagerrak strait in the east (Fig. 1). With the exception of riverine input, all data and code is open source making this configuration reproducible. Where applicable all scripts and configuration files are available in the PML NEMO project template repository on github: https://github.com/pmlmodelling/NEMO_project_template/tree/AMM7
Acute and partial life-cycle toxicity of a tri-polymer blend of microplastics in the copepod Acartia tonsa
Full text linkMicroplastics are a prolific environmental contaminant that pose a risk to marine organisms. Ecotoxicological
studies have identified microplastics can cause sub-lethal harm to aquatic biota. However, prior studies often
lack comparability and environmental relevance, for example focussing upon monodisperse beads at extremely
high concentrations. Copepods are keystone marine taxa that play vital roles in the marine food web and
biogeochemical cycling. In this study, we adapted ISO methods to conduct acute and partial life-cycle toxicity
tests exposing adult and juvenile life stages of the copepod Acartia tonsa to a fully characterised tri-polymer
microplastic blend comprising cryoground polyethylene, polypropylene, and nylon particles (5–100 μm) at
concentrations ranging 0–1000 μg L− 1 . The tests considered the toxicity of microplastics on a wide number of endpoints including adult survival, algal ingestion rates, egg production and size, larval development ratio and juvenile survival. Mortality, egg size and larval development ratio proved to be the most sensitive endpoints. The tri-polymer blend had an LC5072h value of 182 μg L− 1 providing a baseline for future toxicity testing using this
method
Will the declining sea ice extent in the Arctic cause a reversal of net benthic-pelagic exchange directions?
Full text linkIn the Arctic, loss of sea ice due to climate change and the northward shift of the Polar Front are predicted to
affect many ecosystem processes such as the ecologically important process of particulate and dissolved matter
exchange between the seafloor and the water column. In this study, we show for the first time that a change from
an ice-covered, Arctic water-dominated system to an Atlantic -dominated ice-free one is likely to reverse seafloorwater exchange directions. A north – south transect across the Barents Sea was studied over two years with
differing sea ice cover conditions, recording biological, biogeochemical, hydrographic, geophysical, and
oceanographic data. There was a clear difference between the direction and magnitude of key benthic-pelagic
fluxes present at Atlantic-dominated environments, and those in Arctic water – dominated ones. Currently, the southern Barents Sea exhibits a net downward flux of dissolved matter and a net upward flux of particulates, while in the northern region solutes fluctuate upwards and particulates downward, making the North a more depositional region that promotes near-surface primary productivity. Broad scale assessments of net fluxes in rapidly changing ecosystems should be employed to monitor impacts of climate change and anthropogenic activities
Resource acquisition in diel cycles and the cost of growing quickly
Full text linkMany organisms, notably phototrophs, routinely acquire resources over only a fraction of the day. They have to balance their main period of initial biosynthesis against cell cycle events. Because of their short generation times, this challenge is especially acute for the planktonic microalgae that perform 50% of global C-fixation. Empirical evidence indicates that microalgal day-average growth is a function of the ability to acquire resources rapidly when available, retaining initial products of assimilation to support growth. A fundamental question arises over the optimal physiological configuration to support such activity. Here, we applied computer simulations implementing a development of the quota concept, in which the internal limiting resource is itself C, ratioed against total organism C-biomass. The model comprises metabolite and core pools of carbon C ( M C and C C , respectively), with growth modulated by M C /( M C + C C ); M C supports growth of C C in the absence of concurrent resource acquisition. Dynamic feedback interactions from the relative size of M C controls resource acquisition. The model reproduces the general pattern of growth at different light:day fraction ( LD ), and of afternoon-depression of C-fixation. We explored the efficiency of the physiological cell configuration to locate optimal configurations at different combinations of maximum growth rates ( U max ) and LD values across plausible parameter values for microalgae. While the optimum maximum resource acquisition rate deployed during the L phase scales with U max / LD , the maximum size of the metabolite pool scales to LD / DV , where DV is division time (i.e. U max /Ln(2)). Accordingly, we conclude that faster growing organisms carry a penalty limiting their geographic spread to latitudes and seasons where LD is high. Larger, vacuolated organisms (such as diatoms), having a bigger metabolite compartment, may be at an advantage in such situations
The theoretical role of the wind in aerosolising microplastics and nanoplastics from coastal combined sewer overflows
Full text linkInhaled microplastics and nanoplastics (MNPs) have shown bio-persistence in the body, with concerning implications for human health. Airborne MNPs primarily originate from terrestrial sources, but sea air may contribute when onshore ‘aerosolising’ winds coincide with high concentrations of MNPs in surface waters. From the thousands of cities worldwide with Combined Sewer Overflows, millions to billions of MNPs can be discharged daily into rivers, estuaries, and the sea. To assess the possible links between water pollution and air quality, we analysed two years of Combined Sewer Overflows (spills) off Plymouth, UK, alongside same-day and long-term meteorological and satellite data. Winds exceeding 6.5 m/s were applied as the theoretical threshold for marine aerosol production at the sea surface. From 2022 to 2023, sewer spills into Plymouth Sound coincided with onshore aerosolising winds for a minimum of 178 days. Specifically, MNPs may have been stripped from coastal spills and blown back inland for over 1,586 hours, amounting to at least 10% of the 2-year period. Surprisingly, rainfall was too weakly correlated with spills to be a predictor, with little to no precipitation for 18% of sewer overflow events overall. In the satellite data, river plumes coincident with spills remained detectable ~ 10 km offshore, and we observed a significant degradation in winter water clarity over the past decade. Given the global footprint of outdated sewage infrastructure, our findings suggest that coastal spills—when combined with onshore aerosolising winds—may serve as an overlooked source of airborne MNPs. To better understand potential exposure pathways, it is essential that future scientific studies integrate air quality monitoring with assessments of coastal water quality
Segmenting and characterising ripple patterns on sand dunes using machine learning and 2D semi-variogram
Full text linkSand ripples, shaped by fluid flow like wind or water, are common on dunes on Earth and Mars. Their patterns reveal local transport conditions, offering insights into wind regimes where direct observations are lacking. Since manual mapping is slow and subjective, automated methods are essential for consistent large-scale analysis. This study presents two novel and complementary methods for mapping ripple patterns on Martian dunes using high-resolution imagery: a U-Net model for pattern classification and a 2D semi-variogram for measuring ripple spacing and orientation. Tested on 42 barchan dunes across six Martian regions, the U-Net showed reliable ripple classification (F1-score 79 %), while the variogram method achieved high accuracy for ripple spacing (R2 = 0.78) and orientation (R2 = 0.98). Together, these approaches enable efficient, large-scale analysis of ripples for sediment transport on any planetary surface and can be applied to other patterned features
Euphotic iodate production along an Atlantic Meridional Transect
No full textThe oxidized iodine species, iodate, is abundant in well‑oxygenated marine waters and can be tracked in sediments to reconstruct ancient oxygen availability. Despite known modern marine spatial variations in both iodate
and reduced iodide, the rates, pathways, and locations of iodate formation remain poorly understood for temporal gradients across Earth history. To quantify rates and pathways of iodate formation across an ocean basin,
we performed ship-board tracer experiments in euphotic waters with known gradients in iodine speciation on an
Atlantic Meridional Transect (45◦S and 37◦N). We performed incubations at depths corresponding to 7 % and 1
% of ambient surface light levels, thus tracking the boundaries of the deep chlorophyl maximum (DCM), from 11
stations along the transect. All incubations were spiked with a 129I (t1/2≈15.7 My) tracer and mimicked ambient
conditions. We observed iodate production via multiple pathways. The most common observation was a lack of
significant iodate production, with iodate production limited to 7 of the 22 locations and nearly exclusively
observed at the DCM and outside the nitrogen and iron limited South Atlantic Gyre. Iodate formation from direct
iodide oxidation is inferred in only two locations based on increases in iodate 129I/127I ratios. At the other locations, decreases in iodate 129I/127I ratios imply that rapid reactions with and overturning of alternative natural
iodine pools, likely iodine intermediates, are an important factor for iodate production. Our work emphasizes
that the rates and pathways of iodate production are spatially heterogenous in the Atlantic Ocean. Future work is
needed to determine the drivers, temporal variations, and trends within global ocean basins
Ocean extremes as a stress test for marine ecosystems and society
No full textIn 2023–2024, widespread marine heatwaves associated with record ocean temperatures impacted ocean processes, marine species, ecosystems and coastal communities, with economic consequences. Despite warnings, interventions were limited. Proactive strategies are needed for inevitable future event
De-novo Genome Assembly of the Edwardsiid Anthozoan Edwardsia elegans
No full textCnidarians (sea anemones, corals, hydroids, and jellyfish) are a key outgroup for comparisons with bilaterial animals to trace the evolution of genomic complexity and diversity within the animal kingdom, as they separated from most other animals 100s of millions of years ago. Cnidarians have extensive diversity, yet the paucity of genomic resources limits our ability to compare genomic variation between cnidarian clades and species. Here we report the genome for Edwardsia elegans, a sea anemone in the most specious genus of the family Edwardsiidae, a phylogenetically important family of sea anemones that contains the model anemone Nematostella vectensis. The E. elegans genome is 396 Mb in length and predicted to encode approximately 49,000 proteins. We annotated large conservation of macrosynteny between E. elegans and other Edwardsiidae anemones as well as conservation of both microRNAs and ultra conserved noncoding elements previously reported in other cnidarians species. We also highlight microsyntenic variation of clustered developmental genes and ancient gene clusters that vary between species of sea anemones, despite previous research showing conservation between cnidarians and bilaterians. Overall, our analysis of the E. elegans genome highlights the importance of using multiple species to represent a taxonomic group for genomic comparisons, where genomic variation can be missed for large and diverse clade