Advancing the understanding of coastal disturbances with a network‐of‐networks approach

Ecosphere, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 1, 2025

Abstract Coastal ecosystems are at the nexus of many high priority challenges in environmental sciences, including predicting influences compounding disturbances exacerbated by climate change on biogeochemical cycling. While research coastal science is fundamentally transdisciplinary—as drivers and ecological processes often span scientific domains—traditional place–based approaches still employed to understand ecosystems. We argue that a macrosystems perspective, integration across distributed sites, crucial how affect suggest grand challenge questions, such as advancing continental‐scale process understanding extreme events global change, will only be addressed using network‐of‐networks approach. identify specific ways existing efforts can maximize benefit multiple interested parties, where additional infrastructure investments might increase return‐on‐investment along coast, continental United States case study.

Language: Английский

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Dynamic soil columns simulate Arctic redox biogeochemistry and carbon release during changes in water saturation

Scientific Reports, Journal Year: 2025, Volume and Issue: 15(1)

Published: Jan. 24, 2025

Abstract Thawing Arctic permafrost can induce hydrologic change and alter redox conditions, shifting the balance of soil organic matter (SOM) decomposition. There remains uncertainty about how saturation transitions impact dissolved gas phase carbon fluxes, efforts to link hydrobiogeochemical processes ecosystem-scale models are limited. This study evaluates SOM decomposition tundra soils using column experiments, water chemistry measurements, microbial community analysis, a PFLOTRAN reactive transport model. Soil columns from thermokarst channel (TC) an upland (UC) were exposed cycles drainage, which controlled emissions. During saturation, outflow UC correlated with elevated reduced iron decreased pH; during dioxide fluxes 70% higher than TC fluxes. Intermittent methane release was observed for TC, consistent methanogen abundance. Slower drainage in more subtle biogeochemical changes. simulations captured experimental trends oxygen concentrations, contents. The model then used evaluate additional rates. emphasizes importance considering when evaluating simulating dynamic environments.

Language: Английский

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ELM‐Wet: Inclusion of a Wet‐Landunit With Sub‐Grid Representation of Eco‐Hydrological Patches and Hydrological Forcing Improves Methane Emission Estimations in the E3SM Land Model (ELM)

Journal of Advances in Modeling Earth Systems, Journal Year: 2025, Volume and Issue: 17(2)

Published: Feb. 1, 2025

Abstract Wetlands are the largest emitters of biogenic methane (CH 4 ) and represent highest source uncertainty in global CH budgets. Here, we aim to improve realism wetland representation U.S. Department Energy's Exascale Earth System Model land surface model, ELM, thereby reducing flux predictions. We develop an updated version, ELM‐Wet, where activate a separate landunit for wetlands that handles multiple wetland‐specific eco‐hydrological patch functional types. introduce more realistic hydrological forcing through prescribing site‐level constraints on water elevation, which allows resolving different sustained inundation depth patches, if data exists, depth. modified calculation aerenchyma transport diffusivity based observed conductance per leaf area vegetation use Bayesian Optimization parameterize CO 2 fluxes developed wet‐landunit. Site‐level simulations coastal non‐tidal freshwater Louisiana were performed with model. Eddy covariance observations from 2012 2013 used train model 2021 validation. Patch‐specific chamber concentration profiles soil porewater evaluation performance. Our results show ELM‐Wet reduces model's emission root mean squared error by up 33% is able inter‐daily variability across wetland's including during periods extreme dry or wet conditions.

Language: Английский

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Strong heterogeneity in laterally exchanged particulate organic matter across tidal marshes in a large river delta

Environmental Research, Journal Year: 2025, Volume and Issue: unknown, P. 121740 - 121740

Published: April 1, 2025

Language: Английский

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Short-Term Groundwater Level Fluctuations Drive Subsurface Redox Variability

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(33), P. 14687 - 14697

Published: Aug. 8, 2024

As global change processes modify the extent and functions of terrestrial–aquatic interfaces, variability critical dynamic transitional zones between wetlands uplands increases. However, it is still unclear how fluctuating water levels at these boundaries alter groundwater biogeochemical cycling. Here, we used high-temporal resolution data along gradients from to during freshwater coastal areas capture spatiotemporal patterns redox potential (Eh). We observed that topography influences Eh higher in than wetlands; however, high within TAI challenged establishment distinct zonation. Declining generally decreased Eh, but most locations exhibited significant variability, which associated with rare instances short-term level fluctuations, introducing oxygen. The Eh-oxygen relationship showed hysteresis patterns, reflecting poising capacity maintaining more oxidizing states longer dissolved oxygen presence. Surprisingly, frequent uplands. infer occasional entering specific wetland–upland acts as control points. High-resolution can such yet instances, supporting redox-informed models advancing predictability climate feedback.

Language: Английский

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Simulated plant-mediated oxygen input has strong impacts on fine-scale porewater biogeochemistry and weak impacts on integrated methane fluxes in coastal wetlands

Biogeochemistry, Journal Year: 2024, Volume and Issue: 167(7), P. 945 - 963

Published: May 23, 2024

Abstract Methane (CH 4 ) emissions from wetland ecosystems are controlled by redox conditions in the soil, which currently underrepresented Earth system models. Plant-mediated radial oxygen loss (ROL) can increase soil O 2 availability, affect local conditions, and cause heterogeneous distribution of redox-sensitive chemical species at root scale, would CH integrated over larger scales. In this study, we used a subsurface geochemical simulator (PFLOTRAN) to quantify effects incorporating either spatially homogeneous ROL or more complex on model predictions porewater solute concentration depth profiles (dissolved organic carbon, methane, sulfate, sulfide) column fluxes for tidal coastal wetland. From simulation, obtained 18% higher averaged rooting zone but 5% lower total flux compared simulations without ROL. This difference is because concentrations occurred same rhizosphere volume that was directly connected with plant-mediated transport atmosphere. Sensitivity analysis indicated impacts sulfide will be important under (lower densities). Despite small impact predicted emissions, simulated drastically reduced sulfide, an effective phytotoxin, indicating combined sulfur cycling into ecosystem models could potentially improve plant productivity ecosystems.

Language: Английский

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Integrated Effects of Site Hydrology and Vegetation on Exchange Fluxes and Nutrient Cycling at a Coastal Terrestrial‐Aquatic Interface

Water Resources Research, Journal Year: 2024, Volume and Issue: 60(6)

Published: June 1, 2024

Abstract The complex interactions among soil, vegetation, and site hydrologic conditions driven by precipitation tidal cycles control the biogeochemical transformations bi‐directional exchange of carbon nutrients across terrestrial–aquatic interfaces (TAIs) in coastal regions. This study uses a highly mechanistic model, Advanced Terrestrial Simulator (ATS)‐PFLOTRAN, to explore how these affect exchanges materials nitrogen cycling. We used transect Chesapeake Bay region that spans zones open water, wetland, transition, upland forest. designed several simulation scenarios parse effects individual controlling factors sensitivity cycling reaction rate parameters derived from laboratory experiments. Our simulations reveal an active zone for under transition between wetland upland. Evapotranspiration is found enhance fluxes surface subsurface domains, resulting higher dissolved oxygen concentration TAIs. transport organic plant leaves roots provide additional source needed aerobic respiration denitrification processes variability associated with microbial activities also play dominant role heterogeneity dynamics simulated redox conditions. modeling‐focused exploratory enabled us better understand water microbes govern hydro‐biogeochemical at TAIs, which important step toward representing ecosystems larger‐scale Earth system models.

Language: Английский

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Fluctuations and Benthic Flux of Inorganic Nutrients Associated with Tidal Cycles and Its Implications to the Outwelling Process in Garolim Bay, Yellow Sea

Ocean Science Journal, Journal Year: 2024, Volume and Issue: 60(1)

Published: Dec. 20, 2024

Language: Английский

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Interactive effects of salinity, redox, and colloids on greenhouse gas production and carbon mobility in coastal wetland soils

PLoS ONE, Journal Year: 2024, Volume and Issue: 19(12), P. e0316341 - e0316341

Published: Dec. 30, 2024

Coastal wetlands, including freshwater systems near large lakes, rapidly bury carbon, but less is known about how they transport carbon either to marine and lake environments or the atmosphere as greenhouse gases (GHGs) such dioxide methane. This study examines GHG production organic matter (OM) mobility in coastal wetland soils vary with availability of oxygen other terminal electron acceptors. We also evaluated OM redox-sensitive species varied across different size fractions: particulates (0.45-1μm), fine colloids (0.1-0.45μm), nano plus truly soluble (<0.1μm; NP+S) during 21-day aerobic anaerobic slurry incubations. Soils were collected from center a (FW-C) Lake Erie, upland-wetland edge same (FW-E), saline (SW-C) Pacific Northwest, USA. Anaerobic methane for FW-E 47 27,537 times greater than FW-C SW-C soils, respectively. High Fe2+ dissolved sulfate concentrations suggest that iron and/or reduction inhibited methanogenesis. Aerobic CO2 was highest both which had higher proportion NP+S fraction (64±28% 70±10% FW-E, respectively) C:N ratios reflective microbial detritus (5.3±5.3 5.3±7.0 FW-C, compared SW-C, particulate (58±9%) colloidal (19±7%) vegetation (11.4 ± 1.7). The variability shifts fractionation composition observed within individual sites reinforce high spatial processes controlling stability, mobility, bioavailability soils.

Language: Английский

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