Climate change and terrigenous inputs decrease the efficiency of the future Arctic Ocean’s biological carbon pump

Nature Climate Change, Journal Year: 2025, Volume and Issue: 15(2), P. 171 - 179

Published: Jan. 6, 2025

Abstract The Arctic experiences climate changes that are among the fastest in world and affect all Earth system components. Despite expected increase terrigenous inputs to Ocean, their impacts on biogeochemical cycles currently largely neglected IPCC-like models. Here we used a state-of-the-art high-resolution ocean biogeochemistry model includes carbon nutrient from rivers coastal erosion produce twenty-first-century pan-Arctic projections. Surprisingly, even with an anticipated rise primary production across wide range of emission scenarios, our findings indicate change will lead counterintuitive 40% reduction efficiency Arctic’s biological pump by 2100, which contribute 10%. Terrigenous also drive intense CO 2 outgassing, reducing Ocean’s sink at least 10% (33 TgC yr −1 ). These unexpected reinforced feedback, mostly due accelerated remineralization rates, lower capacity for sequestering carbon.

Language: Английский

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Heatwave responses of Arctic phytoplankton communities are driven by combined impacts of warming and cooling

Science Advances, Journal Year: 2024, Volume and Issue: 10(20)

Published: May 17, 2024

Marine heatwaves are increasing in frequency and intensity as climate change progresses, especially the highly productive Arctic regions. Although their effects on primary producers will largely determine impacts ecosystem services, mechanistic understanding phytoplankton responses to these extreme events is still very limited. We experimentally exposed assemblages stable warming, well repeated heatwaves, measured temporally resolved productivity, physiology, composition. Our results show that even warming increases while response depends specific scenario applied not predictable from responses. This appears be due underestimated impact of cool phase following a heatwave, which can at least important warm for overall response. physiological compositional adjustments both phases drive productivity need considered mechanistically predict impacts.

Language: Английский

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The changing nature of future Arctic marine heatwaves and its potential impacts on the ecosystem

Nature Climate Change, Journal Year: 2025, Volume and Issue: 15(2), P. 162 - 170

Published: Jan. 6, 2025

Abstract Marine heatwaves (MHWs), defined as extreme ocean warming episodes, have strengthened over the past decades. High-resolution climate models improve understanding of MHWs under global warming, but such events in future Arctic are currently overlooked. In a high-resolution model, we find intensify on orders magnitude during twenty-first century, following sea ice retreat. However, with little coverage, strong interannual variability emerges, which could surpass amplitude former intensification. Furthermore, enhancement correlates an order increase rate change temperature anomaly. Additionally, found to be accompanied by stratification enhancement, stratification. Such fluctuations combined suggest major challenges for ecosystems, and may negatively impact food webs through direct physiological effects, well indirectly nutrient supply taxonomic shifts.

Language: Английский

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Sonosynthetic Cyanobacteria Oxygenation for Self‐Enhanced Tumor‐Specific Treatment

Advanced Science, Journal Year: 2024, Volume and Issue: 11(29)

Published: June 12, 2024

Abstract Photosynthesis, essential for life on earth, sustains diverse processes by providing nutrition in plants and microorganisms. Especially, photosynthesis is increasingly applied disease treatments, but its efficacy substantially limited the well‐known low penetration depth of external light. Here, ultrasound‐mediated reported enhanced sonodynamic tumor therapy using organic sonoafterglow (ultrasound‐induced afterglow) nanoparticles combined with cyanobacteria, demonstrating proof‐of‐concept sonosynthesis (sonoafterglow‐induced photosynthesis) cancer therapy. Chlorin e6, a typical small‐molecule chlorine, formulated into to stimulate cyanobacteria sonosynthesis, which serves three roles, i.e., overcoming tissue‐penetration limitations light sources, reducing hypoxia, acting as sonosensitizer vivo suppression. Furthermore, sonosynthetic oxygenation suppresses expression hypoxia‐inducible factor 1α, leading reduced stability downstream SLC7A11 mRNA, results glutathione depletion inactivation peroxidase 4, thereby inducing ferroptosis cells. This study not only broadens scope microbial nanomedicine also offers distinct direction sonosynthesis.

Language: Английский

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Eukaryotic cell size regulation and its implications for cellular function and dysfunction

Physiological Reviews, Journal Year: 2024, Volume and Issue: 104(4), P. 1679 - 1717

Published: June 20, 2024

Depending on cell type, environmental inputs, and disease, the cells in human body can have widely different sizes. In recent years, it has become clear that size is a major regulator of function. However, we are only beginning to understand how optimization function determines given cell’s optimal size. Here, review currently known control strategies eukaryotic intricate link intracellular biomolecular scaling, organelle homeostasis, cycle progression. We detail size-dependent regulation early development impact differentiation. Given importance for normal cellular physiology, must account changing conditions. describe sense stimuli, such as nutrient availability, accordingly adapt their by regulating growth Moreover, discuss correlation pathological states with misregulation long time this was considered downstream consequence dysfunction. newer studies reveal reversed causality, misregulated leading pathophysiological phenotypes senescence aging. summary, highlight important roles dysfunction, which could implications both diagnostics treatment clinic.

Language: Английский

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Temperature orchestrates phytoplankton community and environment in mountain stream for enhancing resource use efficiency

Frontiers in Marine Science, Journal Year: 2025, Volume and Issue: 12

Published: March 20, 2025

Warming is a key factor influencing the function of structure and phytoplankton communities. However, impacts temperature on resource use efficiency (RUE) in mountain rivers remain poorly understood. Here, spatiotemporal patterns community (biomass, composition, diversity), (RUE), main environmental factors high-latitude mountainous stream were investigated to assess how affects RUE. The results showed that species richness, biomass, RUE all increased with rising temperature, richness significantly higher. There was shift from dominated by Cyanophyta at lower temperatures Cryptophyta higher temperatures. Phytoplankton positively correlated but no significant relationship observed between Pielou’s evenness. Furthermore, redundancy analysis Mantel tests revealed water nutrient (TP, NH 4 + -N) physicochemical variable (flow velocity, dissolved oxygen) explained 40.40% overall variation exhibited stronger responses variables than biomass or diversity. highlighted directly affected composition enhanced altering conditions biodiversity. Temperature plays crucial role shaping communities rivers. Our contribute deep understanding mechanisms which influences providing basis for sustainable management conservation aquatic ecosystems watersheds.

Language: Английский

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Snow algae exhibit diverse motile behaviors and thermal responses

mBio, Journal Year: 2025, Volume and Issue: unknown

Published: April 1, 2025

ABSTRACT Snow algal blooms influence snow and glacier melt dynamics, yet the mechanisms involved in community assemblage, development, dispersal are not well understood. While microbial swimming behavior contributes significantly to productivity organization of aquatic terrestrial microbiomes, potential impact cell motility melting on formation visible, large-scale surface bloom patterns is largely unknown. Here, using video tracking phototaxis experiments unique isolates, we evaluated diverse taxa from green, red, golden colored response light thermal gradients. We show that many species efficient cryophilic microswimmers with speed optima below 10°C although cryotolerant traits were also identified. The significant algae at low temperatures, a result specialized adaptations, supports importance active movement life histories inhabiting meltwater. However, diversity performance reveal range evolutionary outcomes sensitivity motile stages dynamic environments. IMPORTANCE Swimming fundamental mechanism controls assembly, structure, microbiomes across environments highly sensitive temperature. Especially, role activity very temperatures snowmelt has been hypothesized, but studied. By examining modeling curves speed, data key may have further important impacts ecology rates ice polar alpine regions.

Language: Английский

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Intraspecific diversity in thermal performance determines phytoplankton ecological niche

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Feb. 15, 2024

Abstract Temperature has a primary influence on phytoplankton physiology and affects biodiversity ecology. To examine how intraspecific diversity temperature shape plankton populations, we grew 12 strains of the ecologically-important coccolithophore Gephyrocapsa huxleyi isolated from regions different for ∼45 generations (2 months), each at 6-8 temperatures, characterized acclimated thermal response curve strain. Even with virtually identical optima overlapping cell size, strain growth rates varied between 0.45 1 day -1 . While some curves were effectively symmetrical, others had more slowly declining above “thermal optimum,” niche widths 16.7 24.8 °C. This suggests that use distinct mechanisms. We investigated ecological implications such using an ocean ecosystem simulation resolving phenotypes. Resolving model analogs “generalists” “specialists” (similar to those observed in G. huxleyi) resulted distinctive global biogeography preferred nonlinear latitudinal pattern. leveraged output predict ranges studied laboratory demonstrated this approach could refine predictions geographic range situ Our combination traits modeled highlights capacity diverse groups persist through shifts. Significance Statement Intraspecific may underpin their distribution. show within single species, have trait parameters. For example, many variable temperatures which they survive (thermal width). Adding width impacted coexistence overall biomass. These observations is gap representation models impacts concomitant carbon cycle dynamics. Including tolerance crucial predictive modeling as dynamics change.

Language: Английский

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Cell size, density, and nutrient dependency of unicellular algal gravitational sinking velocities

Science Advances, Journal Year: 2024, Volume and Issue: 10(27)

Published: July 5, 2024

Eukaryotic phytoplankton, also known as algae, form the basis of marine food webs and drive carbon sequestration. Algae must regulate their motility gravitational sinking to balance access light at surface nutrients in deeper layers. However, regulation remains largely unknown, especially motile species. Here, we quantify velocities according Stokes’ law diverse clades unicellular microalgae reveal cell size, density, nutrient dependency velocities. We identify a algal species, Tetraselmis sp., that sinks faster when starved due photosynthesis-driven accumulation carbohydrates loss intracellular water, both which increase density. Moreover, is connected proliferation can respond multiple nutrients. Overall, our work elucidates how size density environmental conditions vertical migration algae.

Language: Английский

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Effects of Seasons and Successive Upwelling Phases on Phytoplankton Size Classes in the Southeast Arabian Sea

Marine Environmental Research, Journal Year: 2024, Volume and Issue: 198, P. 106568 - 106568

Published: May 28, 2024

Language: Английский

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