Marine heatwaves in the Subarctic and the effect of acute temperature change on the key grazer Strongylocentrotus droebachiensis (Echinoidea, Echinodermata) DOI Creative Commons
Marie Koch, Simon Jungblut, Sandra Götze

и другие.

ICES Journal of Marine Science, Год журнала: 2024, Номер unknown

Опубликована: Дек. 3, 2024

Abstract Subarctic fjord systems are facing a continuous temperature increase as well more frequent and intense marine heatwaves (MHWs). MHWs periods of exceptionally high temperatures above the long-term average. In Porsangerfjord (Northern Norway), average water ranges from 2.5°C in March to 10°C August. frequently exceed summer maximum by up 6°C with so far unknown ecological effects. The green sea urchin, Strongylocentrotus droebachiensis, is key grazer on habitat-forming kelp systems. At abundances, urchins transform productive beds through pronounced grazing into depleted urchin barrens. laboratory experiment, we investigated influence acute change activity metabolic performance urchin. Grazing rates increased continuously 2 but decreased again at 14°C. 22°C, rapid decay were associated changes energy state aerobiosis anaerobiosis. We propose two scenarios: Moderate warming might lead proliferation population pressure forests, while extreme warming, predicted end century, occurrence MHWs, may severely impair and, turn, favour adaptable species.

Язык: Английский

Kelp forest community structure and demography in Kongsfjorden (Svalbard) across 25 years of Arctic warming DOI Creative Commons
Luisa Düsedau,

Stein Fredriksen,

Markus Brand

и другие.

Ecology and Evolution, Год журнала: 2024, Номер 14(6)

Опубликована: Июнь 1, 2024

Abstract The Arctic archipelago of Svalbard is a hotspot global warming and many fjords experience continuous increase in seawater temperature glacial melt while sea‐ice cover declines. In 1996/1998, 2012–2014, 2021 macroalgal biomass species diversity were quantified at the study site Hansneset, Kongsfjorden (W‐Spitsbergen) order to identify potential changes over time. 2021, we repeated earlier studies by stratified random sampling (1 × 1 m 2 , n = 3) along sublittoral depth transect (0, 2.5, 5, 10, 15 m) investigated lower limits dominant brown algae between 3 19 m. maximum fresh weight (FW) all seaweeds was 11.5 kg −2 2.5 99.9% constituted kelp. Although distribution not significantly different compared 2012/2013, digitate kelp community ( Laminaria digitata / Hedophyllum nigripes ) had transformed into an Alaria esculenta ‐dominated forest. Consequently, pronounced shift forest structure occurred time as demonstrate that allocation thallus parts species‐specific. Over past decade, demography changed balanced age kelps (juveniles plus older individuals) only apparent addition, abundances declined noticeably last 25 years red algal flora abundance remained unchanged depth. We propose major factor driving observed are alterations underwater light climate, situ data showed increasing turbidity decreasing irradiance since 2012 2017, respectively. As consequence, interplay retreat levels caused coastal darkening gain with temperatures will possibly intensify future unforeseen consequences for melting coasts fjord ecosystem services.

Язык: Английский

Процитировано

8

Climate-driven changes in underwater irradiance and primary productivity in an Antarctic fjord (Potter Cove, Western Antarctic Peninsula) DOI Creative Commons
Dolores Deregibus, María Liliana Quartino,

Eduardo Ruiz Barlett

и другие.

The Science of The Total Environment, Год журнала: 2025, Номер 960, С. 178249 - 178249

Опубликована: Янв. 1, 2025

Язык: Английский

Процитировано

0

Differential effects of warming on carbon budget, photosynthetic yield and biochemical composition of cold-temperate and Arctic isolates of Laminaria digitata (Phaeophyceae) DOI Creative Commons
Angelika Graiff, Kiara Franke, Ulf Karsten

и другие.

Journal of Plant Physiology, Год журнала: 2025, Номер 306, С. 154436 - 154436

Опубликована: Янв. 22, 2025

Cold-temperate and Arctic hard bottom coastal ecosystems are dominated by kelp forests, which have a high biomass production provide important ecosystem services, but subject to change due ocean warming. However, the photophysiological response increasing temperature of ecologically relevant species, such as Laminaria digitata, might depend on local thermal environment where population has developed. Therefore, effects growth rate, biochemical composition, maximum quantum yield, photosynthetic quotient carbon budget young cultured sporophytes digitata from at Spitsbergen (SPT; 4, 10 16 °C) cold-temperate North Sea island Helgoland (HLG; 10, 22 were comparatively analyzed. Temperature significantly affected rates L. SPT HLG, with highest occurring °C, did not differ between both isolates neither °C nor °C. Nevertheless, yield fixation rate 4 for digitata. Significantly higher oxygen observed in relative Artic respectively. Neither biogeographic region origin quotient, release dissolved or particulate organic carbon. Total mannitol content compared revealing an increased accumulation storage compounds latitude We conclude that HLG their sensitivity temperatures is likely benefit warming, while temperate will be negatively further increases ambient temperature.

Язык: Английский

Процитировано

0

Tracing Macroalgal‐Induced Changes in Carbon Dynamics of High‐Arctic Fjords Using Biomarker Fingerprinting DOI
Biswajit Roy, Archana Singh, Manish Tiwari

и другие.

Journal of Geophysical Research Oceans, Год журнала: 2025, Номер 130(4)

Опубликована: Апрель 1, 2025

Abstract Due to rising seawater temperatures and reduced sea ice extent, the coastal Arctic region is witnessing an expansion of macroalgal forests. However, changes in carbon dynamics resulting from such extensive growth are still unknown high‐Arctic fjords. To trace signatures fjords, bulk C‐isotopic compound‐specific n ‐alkane distributions were studied dominant macroalgae (brown, red, green) ( = 20) also surface sediments 13) inner outer regions Kongsfjorden (Svalbard). The species shows variable signature (−17.0‰ −28.9‰) but similar distribution long‐chain ‐alkanes (> ‐C 23 ) with no predominance homologs, supporting environmental induced ‐alkyl lipid production compared biomass. Despite grain size mineral composition fjord sediments, differences indicate contribution organic matter different sources. In middle region, (−23.3 ± 1.1‰ −23.4 1.3‰) short‐to highlight possible mixing phytoplankton, macroalgal‐debris, terrestrial While, fjord, significantly lower δ 13 C values (−25.6 0.9‰) communities suggest accumulation possibly sourced reworking macroalgal‐debris. High sedimentation microbial breakdown debris create a low‐oxygen environment, as evidenced by higher cyclic octasulphur compounds region. Under future warming conditions, oxygen‐starved fjords may become more common forests expand sediment influx increases.

Язык: Английский

Процитировано

0

Acoustic mapping reveals macroalgal settlement following a retreating glacier front in the High Arctic DOI Creative Commons
Víctor González Triginer,

Milan Beck,

Arunima Sen

и другие.

Frontiers in Marine Science, Год журнала: 2024, Номер 11

Опубликована: Сен. 10, 2024

Vegetated coastal marine ecosystems are projected to expand northwards in the Arctic due climate change, but mechanisms for this expansion complex and nuanced. Macroalgal biomass littoral areas of Svalbard has been increasing, data at glacier fronts very scarce. In study, we use hydroacoustics video validation from an unmanned surface vehicle survey macroalgal bed distribution along coast a High fjord (Billefjorden, Svalbard), including river bays land- sea- terminating fronts, as well oceanographic measurements indicate physical drivers settlement. We found high variation coverage coastline, with virtually no macroalgae abundant little terrestrial runoff. Furthermore, presence kelp was land-terminating front which recently retreated sea, suggests potential rapid establishment newly available substrate following glacial retreat. These findings suggest large ecological implications throughout Arctic, may lead significant changes underwater landscape ecosystem. This study shows that remote autonomous vehicles hydroacoustic mapping sustainable efficient monitoring.

Язык: Английский

Процитировано

2

Impact of climate change on the kelp Laminaria digitata – simulated Arctic winter warming DOI Creative Commons

Moritz Trautmann,

Inka Bartsch, Margot Bligh

и другие.

Frontiers in Marine Science, Год журнала: 2024, Номер 11

Опубликована: Ноя. 8, 2024

The Arctic is seasonally exposed to long periods of low temperatures and complete darkness. Consequently, perennial primary producers have apply strategies maximize energy efficiency. Global warming occurring in the faster than rest globe. highest amplitude temperature rise occurs during Polar Night. To determine stress resistance ecosystem-engineering kelp Laminaria digitata against winter warming, non-meristematic discs adult sporophytes from Porsangerfjorden (Finnmark, Norway) were kept total darkness at 0°C 5°C over a period three months. Physiological variables, namely maximum quantum yield photosynthesis (F v /F m ) dry weight, as well underlying biochemical variables including pigments, storage carbohydrates, carbon nitrogen monitored throughout experiment. Although all samples remained generally good condition with F values above 0.6, L. performed better 5°C. Depletion metabolic products resulted constant decrease weight time. A strong mannitol laminarin was observed, greater reductions 0°C. However, content did not change, indicating that suffering “starvation stress” decline also observed accessory pigments pool xanthophyll cycle particularly Our results indicate has more active metabolism, but lower physiological performance higher winter. Obviously, adapted Night conditions, regardless having its distributional center latitudes. Despite reduced vitality temperatures, serious populations due expected for near future.

Язык: Английский

Процитировано

0

Run-off impacts on Arctic kelp holobionts have strong implications on ecosystem functioning and bioeconomy DOI Creative Commons
Sarina Niedzwiedz,

Claudia Schmidt,

Yunlan Yang

и другие.

Scientific Reports, Год журнала: 2024, Номер 14(1)

Опубликована: Дек. 16, 2024

Kelps (Laminariales, Phaeophyceae) are foundation species along Arctic rocky shores, providing the basis for complex ecosystems and supporting a high secondary production. Due to ongoing climate change glacial terrestrial run-off currently accelerating, drastically changing physical chemical water column parameters, e.g., transparency photosynthetically active radiation or dissolved concentrations of (harmful) elements. We investigated performance functioning kelp holobionts in response gradients, with focus on effect altered element column. found that Saccharina latissima accumulates harmful elements (e.g., cadmium, mercury) originating from coastal run-off. As kelps at food web, this might lead biomagnification, potential consequences high-latitude maricultures. In contrast, biosorption be advantageous monitoring environmental pollution potentially extracting rare earth Further, we relative abundances several kelp-associated microbial taxa significantly responded increasing influence, ecosystem, nutritional value elemental cycling. The responses changes imply cascading ecological economic future scenarios.

Язык: Английский

Процитировано

0

Marine heatwaves in the Subarctic and the effect of acute temperature change on the key grazer Strongylocentrotus droebachiensis (Echinoidea, Echinodermata) DOI Creative Commons
Marie Koch, Simon Jungblut, Sandra Götze

и другие.

ICES Journal of Marine Science, Год журнала: 2024, Номер unknown

Опубликована: Дек. 3, 2024

Abstract Subarctic fjord systems are facing a continuous temperature increase as well more frequent and intense marine heatwaves (MHWs). MHWs periods of exceptionally high temperatures above the long-term average. In Porsangerfjord (Northern Norway), average water ranges from 2.5°C in March to 10°C August. frequently exceed summer maximum by up 6°C with so far unknown ecological effects. The green sea urchin, Strongylocentrotus droebachiensis, is key grazer on habitat-forming kelp systems. At abundances, urchins transform productive beds through pronounced grazing into depleted urchin barrens. laboratory experiment, we investigated influence acute change activity metabolic performance urchin. Grazing rates increased continuously 2 but decreased again at 14°C. 22°C, rapid decay were associated changes energy state aerobiosis anaerobiosis. We propose two scenarios: Moderate warming might lead proliferation population pressure forests, while extreme warming, predicted end century, occurrence MHWs, may severely impair and, turn, favour adaptable species.

Язык: Английский

Процитировано

0