Carbon sequestration and climate change mitigation using macroalgae: a state of knowledge review

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2023, Volume and Issue: 98(6), P. 1945 - 1971

Published: July 12, 2023

The conservation, restoration, and improved management of terrestrial forests significantly contributes to mitigate climate change its impacts, as well providing numerous co-benefits. pressing need reduce emissions increase carbon removal from the atmosphere is now also leading development natural solutions in ocean. Interest sequestration potential underwater macroalgal growing rapidly among policy, corporate sectors. Yet, our understanding whether can lead tangible mitigation remains severely limited, hampering their inclusion international policy or finance frameworks. Here, we examine results over 180 publications synthesise evidence regarding forest potential. We show that research efforts on macroalgae are heavily skewed towards particulate organic (POC) pathways (77% data publications), fixation most studied flux (55%). Fluxes directly (e.g. export burial marine sediments) remain poorly resolved, likely hindering regional country-level assessments potential, which only available 17 150 countries where occur. To solve this issue, present a framework categorize coastlines according Finally, review multiple avenues through translate into capacity, largely depends interventions above baseline avoid further emissions. find restoration afforestation potentially order 10's Tg C globally. Although lower than current estimates value all habitats (61-268 year-1 ), it suggests could add total coastal blue ecosystems, offer valuable opportunities polar temperate areas currently low. Operationalizing will necessitate models reliably estimate proportion production sequestered, improvements fingerprinting techniques, rethinking accounting methodologies. ocean provides major adapt change, largest vegetated habitat Earth should not be ignored simply because does fit existing

Language: Английский

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Major Expansion of Marine Forests in a Warmer Arctic

Frontiers in Marine Science, Journal Year: 2022, Volume and Issue: 9

Published: March 1, 2022

Accelerating warming and associated loss of sea ice are expected to promote the expansion coastal marine forests (macrophytes) along massive Arctic coastlines. Yet, this region has received much less attention compared other global oceans. The available future projections macrophytes still limited few species regions, mostly focused at lower latitude ranges, thus precluding well-informed IPCC impact assessments, conservation management. Here we aim quantify potential distributional changes intertidal subtidal brown macroalgae eelgrass by year 2100, relative present. We estimate habitat suitability means distribution modeling, considering in seawater temperature, salinity, nutrients cover under two greenhouse gas emission scenarios, one consistent with Paris Agreement (RCP 2.6) representing mitigation strategies 8.5). As data on substrate conditions do not exist, models were restricted depth range supporting (down 5 m for 30 macroalgae). Models projected major expansions between 69,940 123,360 km 2 , depending climate scenario, polar limits shifting northwards up 1.5 degrees 21.81 per decade. Such response changing will likely elicit biodiversity ecosystem functions Arctic. Expansions are, however, intense than those already realized over past century, indicating an overall slowing down despite accelerated as habitats become increasingly occupied.

Language: Английский

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Arctic marine forest distribution models showcase potentially severe habitat losses for cryophilic species under climate change

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(11), P. 3711 - 3727

Published: Feb. 25, 2022

The Arctic is among the fastest-warming areas of globe. Understanding impact climate change on foundational marine species needed to provide insight ecological resilience at high latitudes. Marine forests, underwater seascapes formed by seaweeds, are predicted expand their ranges further north in a warmer climate. Here, we investigated whether northern habitat gains will compensate for losses southern range edge modelling forest distributions according three distribution categories: cryophilic (species restricted environment), cryotolerant with broad environmental preferences inclusive but not limited and cryophobic temperate conditions) forests. Using stacked MaxEnt models, current extent suitable contemporary future forests under Representative Concentration Pathway Scenarios increasing emissions (2.6, 4.5, 6.0, 8.5). Our analyses indicate that already ubiquitous north, thus cannot change, resulting an overall loss due severe contractions. within basin, however, remain largely stable notable exceptions some areas, particularly Canadian Archipelago. Succession may occur where extirpated edge, ecosystem shifts towards regimes mid latitudes, though many aspects these shifts, such as total biomass depth range, be field validated. results first global synthesis changes pan-Arctic coastal ecosystems suggest transitions unavoidable now areas.

Language: Английский

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Effects of climate change on marine coastal ecosystems – A review to guide research and management

Biological Conservation, Journal Year: 2023, Volume and Issue: 289, P. 110394 - 110394

Published: Dec. 21, 2023

There is growing concern over climate models that project significant changes in the oceans, with consequences on marine biodiversity and human well-being. However, coastal ecosystems respond differently to change-related stressors depending ecosystem, species composition interactions, geomorphologic settings, spatial distribution, but also presence of local interacting cumulatively pressures. Our paper provides a comprehensive review current literature about effects climate-related pressures how affect their resilience. work focuses key from three ecoregions: Caribbean Sea (coral reefs, mangrove forests, seagrass beds), Mediterranean (the coral Cladocora caespitosa, maërl beds beds) North-East Atlantic, which include kelp beds, salt marshes beds. This highlights need for more comprehensive, multi-species, multi-stressors approach predict better at ecosystem seascape levels ecosystems. Nevertheless, there enough evidence argue addressing locally manageable common multiple ecosystems, such as nutrient enrichment, development, hydrologic disturbances, anchoring or sedimentation, will reduce identified adverse change. knowledge critical practical conservation actions management ecoregion scale beyond.

Language: Английский

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Functional changes across marine habitats due to ocean acidification

Global Change Biology, Journal Year: 2024, Volume and Issue: 30(1)

Published: Jan. 1, 2024

Global environmental change drives diversity loss and shifts in community structure. A key challenge is to better understand the impacts on ecosystem function connect species trait of assemblages with properties that are turn linked functioning. Here we quantify composition associated ocean acidification (OA) by using field measurements at marine CO

Language: Английский

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Seaweed forests are carbon sinks that may help mitigate CO2 emissions: a comment on Gallagher et al. (2022)

ICES Journal of Marine Science, Journal Year: 2023, Volume and Issue: 80(6), P. 1814 - 1819

Published: July 6, 2023

Abstract Recently, Gallagher et al. (2022) suggested that seaweed ecosystems are net heterotrophic carbon sources due to CO2 released from the consumption of external subsidies. Here we outline several flaws in their argument, which believe confuse research on blue potential ecosystems, and unjustifiably generate doubt around initiatives protect restore forests. al.’s evidence relies 18 studies with highly variable measures ecosystem production, do not statistically support conclusion most heterotrophic. This dataset is also inappropriate as it incomplete misrepresents globally, particularly forests, contribute disproportionately global productivity. We maintain climate change mitigation value an depends difference uptake between original its replacement ecosystem. provide drawdown largest flux any vegetated coastal habitat, indeed autotrophic ecosystems. recognize substantial uncertainties remain concerning magnitude by recommend fluxes should be considered more broadly taken into account estimates potential.

Language: Английский

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Local human pressures modulate turf sediment loads in a warm-temperate oceanic island

Marine Environmental Research, Journal Year: 2025, Volume and Issue: 205, P. 107030 - 107030

Published: Feb. 23, 2025

In the Anthropocene, algal turfs are expected to replace macroalgal forests and coral cover as dominant benthic state. These turf seascapes play a key role in regulating ecosystem processes through sediment retention, which carries significant ecological socio-economic implications. However, our understanding of sediments trapped by on coastal reefs, particularly oceanic islands, remains limited. this study, we quantified seascape architecture (algal composition mean height) properties (total particulate load, grain size distribution, organic content) across warm-temperate island. We further decoupled geomorphological, anthropogenic, algae structural predictors explaining spatial variation properties. Our results revealed loads, varying three orders magnitude (∼1 g/m2 2000 g/m2), while load varied two 100 g/m2). Human pressure were strongest highlighting local human stressors modulating dynamics emerging seascapes. study provides baseline information patterns drivers critical area develop management plans that target resilience core functions under altered reef configurations Anthropocene.

Language: Английский

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Climate‐driven shifts in kelp forest composition reduce carbon sequestration potential

Global Change Biology, Journal Year: 2022, Volume and Issue: 28(18), P. 5514 - 5531

Published: June 13, 2022

The potential contribution of kelp forests to blue carbon sinks is currently great interest but interspecific variance has received no attention. In the temperate Northeast Atlantic, forest composition changing due climate-driven poleward range shifts cold Laminaria digitata and hyperborea warm ochroleuca. To understand how this might affect sequestration (CSP) ecosystem, we quantified differences in export decomposition alongside changes detrital photosynthesis biochemistry. We found that while exports up 71% more per plant, it decomposes 155% faster than its boreal congeners. Elemental stoichiometry polyphenolic content cannot fully explain turnover, which may be attributable contrasting tissue toughness or unknown biochemical structural defenses. Faster causes photosynthetic apparatus L. ochroleuca overwhelmed 20 days after lose integrity 36 days, detritus species maintains assimilation. Depending on photoenvironment, could further exacerbate via a positive feedback loop. Through compositional change such as predicted prevalence ochroleuca, ocean warming therefore reduce CSP marine forests.

Language: Английский

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Rapid tropicalization evidence of subtidal seaweed assemblages along a coastal transitional zone

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: July 20, 2023

Abstract Anthropogenic climate change, particularly seawater warming, is expected to drive quick shifts in marine species distribution transforming coastal communities. These will be noticeable biogeographical transition zones. The continental Portuguese coast stretches from north south along 900 km. Despite this short spatial scale, the strong physical gradient intensified by Iberian upwelling creates a zone where seaweed boreal and Lusitanian-Mediterranean origin coexist. On northern coast, kelp forests thrive cold, nutrient-rich oceanic waters. In south, communities resemble Mediterranean-type assemblages are dominated turfs. Recent evidence suggests that these areas, intertidal shifting their edges as result of rising temperatures. Taking advantage previous abundance data collected 2012 subtidal communities, new sampling program was carried out same regions 2018 assess recent changes. results confirmed latitudinal macroalgal assemblages. More importantly we found significant structural functional changes period six years, with regional increases warm-affinity species, small seaweeds like Species richness, diversity, biomass increase, all accompanied an increase community temperature index (CTI). Our findings suggest transitional area have undergone major within few years. Evidence “fast tropicalization” indication effects anthropic change over

Language: Английский

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Local and global stressors as major drivers of the drastic regression of brown macroalgae forests in an oceanic island

Regional Environmental Change, Journal Year: 2024, Volume and Issue: 24(2)

Published: April 15, 2024

Abstract Similar to other coastal regions worldwide, forests created by brown macroalgae have severely declined in recent decades across the Macaronesian oceanic archipelagos (northeastern Atlantic), eroding provision of ecosystem services. However, putative effects natural and anthropogenic stressors (both local global) on such declines spatial temporal scales remain unresolved. Our research endeavored investigate connection between global distribution extent Gongolaria abies-marina rocky intertidal adjacent subtidal zones Gran Canaria over past four decades. We also quantified presence populations at small scales, according micro-habitat topography (“open rock” versus “refuge”). Through herbarium records, we additionally analyzed historical variation thallus size species. Finally, experimentally assessed thermotolerance embryonic stages warming. The main environmental drivers explaining regression G. were increasing number marine heatwaves, while human impacts (quantified through HAPI index) accounted for further forests. Warming reduced survival macroalgal embryos. A progressive miniaturization species, currently restricted refuges as a strategy, seems likely be final stage disappearance this from island’s shores.

Language: Английский

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