Global-change effects on early-stage decomposition processes in tidal wetlands – implications from a global survey using standardized litter

Abstract. Tidal wetlands, such as tidal marshes and mangroves, are hotspots for carbon sequestration. The preservation of organic matter (OM) is a critical process by which tidal wetlands exert influence over the global carbon cycle and at the same time gain elevation to keep pace with sea-level rise (SLR). The present study assessed the effects of temperature and relative sea level on the decomposition rate and stabilization of OM in tidal wetlands worldwide, utilizing commercially available standardized litter. While effects on decomposition rate per se were minor, we show strong negative effects of temperature and relative sea level on stabilization, as based on the fraction of labile, rapidly hydrolyzable OM that becomes stabilized during deployment. Across study sites, OM stabilization was 29 % lower in low, more frequently flooded vs. high, less frequently flooded zones. Stabilization declined by ∼ 75 % over the studied temperature gradient from 10.9 to 28.5 ∘C. Additionally, data from the Plum Island long-term ecological research site in Massachusetts, USA, show a pronounced reduction in OM stabilization by > 70 % in response to simulated coastal eutrophication, confirming the potentially high sensitivity of OM stabilization to global change. We therefore provide evidence that rising temperature, accelerated SLR, and coastal eutrophication may decrease the future capacity of tidal wetlands to sequester carbon by affecting the initial transformations of recent OM inputs to soil OM.

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Global change effects on decomposition processes in tidal wetlands: implications from a global survey using standardized litter

10.5194/bg-2017-533 ◽

2017 ◽

Cited By ~ 1

Author(s):

Peter Mueller ◽

Lisa M. Schile-Beers ◽

Thomas J. Mozdzer ◽

Gail L. Chmura ◽

Thomas Dinter ◽

...

Keyword(s):

Organic Matter ◽

Global Change ◽

Sea Level ◽

Decomposition Rate ◽

High Sensitivity ◽

Global Scale ◽

Tidal Marshes ◽

Tidal Wetlands ◽

Coastal Eutrophication ◽

Relative Sea Level

Abstract. Tidal wetlands, such as tidal marshes and mangroves, are hotspots for carbon sequestration. The preservation of organic matter (OM) is a critical process by which tidal wetlands exert influence over the global carbon cycle and at the same time gain elevation to keep pace with sea-level rise (SLR). The present study provides the first global-scale field-based experimental evidence of temperature and relative sea level effects on the decomposition rate and stabilization of OM in tidal wetlands. The study was conducted in 26 marsh and mangrove sites across four continents, utilizing commercially available standardized OM. While effects on decomposition rate per se were minor, we show unanticipated and combined negative effects of temperature and relative sea level on OM stabilization. Across study sites, OM stabilization was 29 % lower in low, more frequently flooded vs. high, less frequently flooded zones. OM stabilization declined by ~ 90 % over the studied temperature gradient from 10.9 to 28.5 °C, corresponding to a decline of ~ 5 % over a 1 °C temperature increase. Additionally, data from the long-term ecological research site in Massachusetts, US show a pronounced reduction in OM stabilization by > 70 % in response to simulated coastal eutrophication, confirming the high sensitivity of OM stabilization to global change. We therefore provide evidence that rising temperature, accelerated SLR, and coastal eutrophication may decrease the future capacity of tidal wetlands to sequester carbon by affecting the initial transformations of recent OM inputs to soil organic matter.

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Use of ‘accommodation space’ in tidal wetlands. A commentary on Kerrylee Rogers’ ‘Accommodation space as a framework for assessing the response of mangroves to relative sea‐level rise’.

Singapore Journal of Tropical Geography ◽

10.1111/sjtg.12360 ◽

2021 ◽

Vol 42 (2) ◽

pp. 184-189

Author(s):

Ken W. Krauss

Keyword(s):

Sea Level Rise ◽

Sea Level ◽

Tidal Wetlands ◽

Relative Sea Level ◽

Accommodation Space ◽

Relative Sea Level Rise

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Stratigraphy, pollen history and geochronology of tidal marshes in a Gulf of Maine estuarine system: Climatic and relative sea level impacts

Marine Geology ◽

10.1016/j.margeo.2008.08.004 ◽

2008 ◽

Vol 256 (1-4) ◽

pp. 1-17 ◽

Cited By ~ 19

Author(s):

Larry G. Ward ◽

Brent J. Zaprowski ◽

Kevin D. Trainer ◽

P. Thompson Davis

Keyword(s):

Sea Level ◽

Gulf Of Maine ◽

Tidal Marshes ◽

Estuarine System ◽

Relative Sea Level

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Modelling salt-marsh vegetation dynamics through species dispersal and competition

10.5194/egusphere-egu21-13174 ◽

2021 ◽

Author(s):

Alvise Finotello ◽

Enrico Bertuzzo ◽

Andrea D'Alpaos ◽

Marco Marani

Keyword(s):

Salt Marsh ◽

Sea Level ◽

Habitat Quality ◽

Salt Marshes ◽

Vegetation Dynamics ◽

Vertical Direction ◽

Tidal Marshes ◽

Spatially Explicit ◽

Shear Stresses ◽

Relative Sea Level

Salt marshes are widespread morphological features in coastal and estuarine tidal landscapes, and are ecologically and economically important as they significantly contribute to coastal primary production, support high biodiversity, and provide a broad range of valuable ecosystem services.The ability of salt marshes to counteract changes in external forcings depends on the complex dynamic interactions between physical and biological processes acting at different spatial and temporal scales. In particular, the evolution of tidal marshes in the vertical direction results from the balance and feedbacks between organic and inorganic deposition, erosion, and changes in relative sea level. For example, colonization of salt marsh platforms by halophytic vegetation enhances both organic and inorganic deposition due to increased flow resistance, reduced bottom shear stresses, capture of sediment particles by plant stems, and direct biomass accumulation. Moreover, halophytes control soil aeration, which feeds back into vegetation zonation and the related biogeomorphic interactions typically observed in tidal marshes.In spite of their importance, however, modeling vegetation dynamics in intertidal marshes remains a major challenge both at the theoretical and practical/numerical level. Improving our current understandings of the mechanisms that drive the zonation of halophytic species is of critical importance to enhance projections of salt-marsh response to changes in climate and relative sea level.Here we present a new bi-dimensional, spatially explicit ecological model aimed to simulate the spatial dynamics of halophytic vegetation in tidal saline wetlands. Vegetation dynamics are treated differently compared to previous models, which employed relatively simple deterministic or probabilistic mechanisms, dictated only by the ability of different species to adapt to different topographic elevations. In our model, in contrast, spatial vegetation dynamics depend not only on the local habitat quality, but also on spatially explicit mechanism of dispersal and competition among multiple, potentially interacting species. The temporal evolution of vegetation biomass at each site depends on death and colonization processes, both local and resulting from dispersal. These processes are modulated for each species by the habitat quality of the considered site. The latter is synthesized only through the local elevation relative to the mean sea level, and is mathematically modeled using a logistic function that represents the theoretical niche of each considered species.Results indicate that such a relatively simple model, where species have elevation-dependent fitness and otherwise neutral traits, can predict realistic diversity and species-richness patterns. More importantly, the model is also able to effectively reproduce the outcome of classical ecological experiments, in which a species is transplanted to an area outside its optimal (realized) niche. A direct comparison clearly shows how previous models not accounting for dispersal and interspecific competitions are unable to reproduce such dynamics.

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Global, regional and local controls on the development of a Triassic carbonate ramp system, Western Balkanides, Bulgaria

Geological Magazine ◽

10.1017/s0016756816000923 ◽

2016 ◽

Vol 155 (3) ◽

pp. 641-673 ◽

Cited By ~ 5

Author(s):

ATHANAS CHATALOV

Keyword(s):

Sea Level ◽

Early Stage ◽

Biological Evolution ◽

Climatic Conditions ◽

Carbonate Ramp ◽

Late Triassic ◽

Carbonate Sediments ◽

Sea Level Changes ◽

Relative Sea Level ◽

Carbonate Production

AbstractThe Early to Late Triassic development of a carbonate ramp system in the subtropical belt of the NW Tethys was controlled by the interplay of several global and regional factors: geotectonic setting (slow continuous subsidence on a passive continental margin), antecedent topography (low-gradient relief inherited from preceding depositional regime), climate and oceanography (warm and dry climatic conditions, storm influence), relative sea-level changes (Olenekian to Anisian eustatic rise, middle Anisian to early Carnian sea-level fall), lack of frame-builders (favouring the maintenance of ramp morphology), and carbonate production (abundant formation of lime mud, non-skeletal grains and marine cements, development of diverse biota controlled by biological evolution and environmental conditions). Elevated palaeorelief affected the ramp initialization on a local scale, while autogenic processes largely controlled the formation of peritidal cyclicity during the early stage of ramp retrogradation. Probably fault-driven differential subsidence caused a local distal steepening of the ramp profile in middle–late Anisian time. The generally favourable conditions promoted long-term maintenance of homoclinal ramp morphology and accumulation of carbonate sediments having great maximum thickness (~500 m). Shutdown of the carbonate factory and demise of the ramp system in the early Carnian resulted from relative sea-level fall and subsequent emergence. After a period of subaerial exposure with minor karstification, the deposition of continental quartz arenites suggests the possible effect of the Carnian Pluvial Episode.

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Plant species determine tidal wetland methane response to sea level rise

Nature Communications ◽

10.1038/s41467-020-18763-4 ◽

2020 ◽

Vol 11 (1) ◽

Author(s):

Peter Mueller ◽

Thomas J. Mozdzer ◽

J. Adam Langley ◽

Lillian R. Aoki ◽

Genevieve L. Noyce ◽

...

Keyword(s):

Global Change ◽

Sea Level Rise ◽

Sea Level ◽

Community Composition ◽

Plant Community ◽

Plant Traits ◽

High Sensitivity ◽

Tidal Wetland ◽

Plant Community Composition ◽

Climate Cooling

Abstract Blue carbon (C) ecosystems are among the most effective C sinks of the biosphere, but methane (CH4) emissions can offset their climate cooling effect. Drivers of CH4 emissions from blue C ecosystems and effects of global change are poorly understood. Here we test for the effects of sea level rise (SLR) and its interactions with elevated atmospheric CO2, eutrophication, and plant community composition on CH4 emissions from an estuarine tidal wetland. Changes in CH4 emissions with SLR are primarily mediated by shifts in plant community composition and associated plant traits that determine both the direction and magnitude of SLR effects on CH4 emissions. We furthermore show strong stimulation of CH4 emissions by elevated atmospheric CO2, whereas effects of eutrophication are not significant. Overall, our findings demonstrate a high sensitivity of CH4 emissions to global change with important implications for modeling greenhouse-gas dynamics of blue C ecosystems.

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Global change and relative sea level rise at Venice: what impact in term of flooding

Climate Dynamics ◽

10.1007/s00382-009-0617-5 ◽

2009 ◽

Vol 35 (6) ◽

pp. 1039-1047 ◽

Cited By ~ 76

Author(s):

Laura Carbognin ◽

Pietro Teatini ◽

Alberto Tomasin ◽

Luigi Tosi

Keyword(s):

Global Change ◽

Sea Level Rise ◽

Sea Level ◽

Relative Sea Level ◽

Relative Sea Level Rise

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Submergence, nutrient enrichment, and tropical storm impacts on Spartina alterniflora in the microtidal northern Gulf of Mexico

Marine Ecology Progress Series ◽

10.3354/meps13342 ◽

2020 ◽

Vol 644 ◽

pp. 33-45

Author(s):

JM Hill ◽

PS Petraitis ◽

KL Heck

Keyword(s):

Gulf Of Mexico ◽

Sea Level Rise ◽

Sea Level ◽

Spartina Alterniflora ◽

Anthropogenic Impacts ◽

Interactive Effects ◽

Relative Sea Level ◽

Hurricane Disturbance ◽

Submergence Stress ◽

Relative Sea Level Rise

Salt marshes face chronic anthropogenic impacts such as relative sea level rise and eutrophication, as well as acute disturbances from tropical storms that can affect the productivity of these important communities. However, it is not well understood how marshes already subjected to eutrophication and sea level rise will respond to added effects of episodic storms such as hurricanes. We examined the interactive effects of nutrient addition, sea level rise, and a hurricane on the growth, biomass accumulation, and resilience of the saltmarsh cordgrass Spartina alterniflora in the Gulf of Mexico. In a microtidal marsh, we manipulated nutrient levels and submergence using marsh organs in which cordgrasses were planted at differing intertidal elevations and measured the impacts of Hurricane Isaac, which occurred during the experiment. Prior to the hurricane, grasses at intermediate and high elevations increased in abundance. After the hurricane, all treatments lost approximately 50% of their shoots, demonstrating that added nutrients and elevation did not provide resistance to hurricane disturbance. At the end of the experiment, only the highest elevations had been resilient to the hurricane, with increased above- and belowground growth. Added nutrients provided a modest increase in above- and belowground growth, but only at the highest elevations, suggesting that only elevation will enhance resilience to hurricane disturbance. These results empirically demonstrate that S. alterniflora in microtidal locations already subjected to submergence stress is less able to recover from storm disturbance and suggests we may be underestimating the loss of northern Gulf Coast marshes due to relative sea level rise.

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