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

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

Authorea (Authorea), Journal Year: 2023, Volume and Issue: unknown

Published: Aug. 7, 2023

The complex interactions among soil, vegetation, and site hydrologic conditions driven by precipitation tidal cycles control biogeochemical transformations bi-directional exchange of carbon nutrients across the terrestrial-aquatic interfaces (TAIs) in coastal regions. This study uses a highly mechanistic model, ATS-PFLOTRAN, to explore how these impact material exchanges nitrogen cycling along TAI transect Chesapeake Bay region that spans zones open water, wetland upland forest. Several simulation scenarios are designed parse effects individual controlling factors sensitivity reaction constants derived from laboratory experiments. Our simulations revealed hot zone for under transition between upland. Evapotranspiration is found enhance fluxes surface subsurface domains, resulting higher dissolved oxygen concentration TAI. transport organic decomposed leaves provides additional source aerobic respiration denitrification processes TAI, while variability rates mediated microbial activities plays dominant role heterogeneity dynamics simulated redox conditions. modeling-focused exploratory enabled us better understand various system components at TAIs hydro-biogeochemical processes, which an important step towards representing ecosystems larger-scale Earth models.

Language: Английский

Aquatic ecosystems science using an imaging spectrometer

Published: Oct. 4, 2023

The study of aquatic ecosystems is an important research area addressing diverse problems such as carbon sequestration in coastal margins and wetlands, kelp seagrass studies, coral reefs, harmful algal blooms hypoxia, cycling this dynamic environment. application imaging spectrometer to ecosystem particularly challenging due low water-leaving radiance levels adjacent the shore region with its higher values. Committee on Earth Observation Satellites (CEOS) has established more stringent performance standards for visible/near infrared wavelengths than are typically available designs. We have recently developed a compact form spectrometer, Chrisp Compact VNIR/SWIR Imaging Spectrometer (CCVIS), that facilitates their modular usage wide field telescope without sacrificing performance. CCVIS design operational concept predicted approaches CEOS standards. envisioned satellite implementation requires pitchback maneuver where slit projected onto surface slowly scanned while recording focal plane array readouts at rate thereby avoiding saturation over land obtaining high signal-to-noise ratio water. effective frame determined by time it takes scan one ground sample distance (GSD). This approach added benefit measuring range angles during single GSD acquisition, providing insight into bidirectional reflectance distribution function (BRDF).

Language: Английский