A5086758240- Climate change and permafrost
- Methane Hydrates and Related Phenomena
- Atmospheric and Environmental Gas Dynamics
- Soil Carbon and Nitrogen Dynamics
- Soil and Unsaturated Flow
- Soil and Water Nutrient Dynamics
- Geological Studies and Exploration
- Indigenous Studies and Ecology
- Marine and coastal ecosystems
- Microbial Community Ecology and Physiology
- Peatlands and Wetlands Ecology
- Coastal wetland ecosystem dynamics
- Wastewater Treatment and Nitrogen Removal
- Legal and Regulatory Analysis
- Geophysics and Gravity Measurements
- Earthquake Detection and Analysis
- Cryospheric studies and observations
- Flood Risk Assessment and Management
- Plant responses to water stress
- Microbial Metabolic Engineering and Bioproduction
- Smart Materials for Construction
- Polar Research and Ecology
- Groundwater and Isotope Geochemistry
- Hydrocarbon exploration and reservoir analysis
- Fire effects on ecosystems
Pacific Northwest National Laboratory
2019-2025
Guangxi Maternal and Child Health Hospital
2024
Government of the United States of America
2022-2023
Smithsonian Environmental Research Center
2023
Oak Ridge National Laboratory
2016-2022
Battelle
2020
University of Science and Technology of China
2018
Bolin Centre for Climate Research
2018
Stockholm University
2018
Nanjing University of Information Science and Technology
2018
The coastal terrestrial-aquatic interface (TAI) is a highly dynamic system characterized by strong physical, chemical, and biological gradients. In particular, shifting soil redox conditions consumption of terminal electron acceptors, due in part to hydrologic conditions, driver carbon availability transformations across TAIs. However, while dynamics are well described, our ability quantitatively forecast rates oxic anoxic shifts soils with different characteristics inundation regimes...
Abstract. The structure, function, and dynamics of Earth's terrestrial ecosystems are profoundly influenced by how often (frequency) long (duration) they inundated with water. A diverse array natural human-engineered systems experience temporally variable inundation whereby fluctuate between non-inundated states. Variable spans extreme events to predictable sub-daily cycles. Variably (VIEs) include hillslopes, non-perennial streams, wetlands, floodplains, temporary ponds, tidal systems,...
Freeze-thaw events disrupt soil pore structure, with implications for larger scale greenhouse gas fluxes and nutrient balance in winter the growing season. Given its strong influence on C N cycling, we need a better understanding of how structure is altered by freeze-thaw disturbances. Our objective was to investigate quantify changes physical soil, response experimental disturbance. We collected intact cores from northern hardwood forest New Hampshire, USA. The soils were held at...
The relationship between plant primary production and wetland methane (CH4) emission is well established. This expected because fuels methanogenesis plants act as conduits for gas exchange the soil atmosphere. Recent global increases in bottom-up measurements of CH4 provide a new opportunity to revisit hypothesis that flux have positive linear wetlands. Using paired gross productivity (GPP) from 56 sites, we found GPP are weakly related, with maximum R2 regressions being 0.14 (p=...
Abstract. Physical injury is common in terrestrial plants as a result of grazing, harvesting, trampling, and extreme weather events. Previous studies demonstrated enhanced emission non-microbial CH4 under aerobic conditions from plant tissues when they were exposed to increasing UV radiation temperature. Since physical also form environmental stress, we sought determine whether it would affect emissions plants. (cutting) stimulated fresh twigs Artemisia species conditions. More cutting...
Abstract. Rapid warming of Arctic ecosystems accelerates microbial decomposition soil organic matter and leads to increased production carbon dioxide (CO2) methane (CH4). CH4 oxidation potentially mitigates emissions from permafrost regions, but it is still highly uncertain whether soils in high-latitude will function as a net source or sink for response rising temperature associated hydrological changes. We investigated potential permafrost-affected degraded ice-wedge polygons on the Barrow...
Abstract The fate of organic carbon (C) in permafrost soils is important to the climate system due large global stocks C. Thawing can be subject dynamic hydrology, making redox processes an factor controlling soil matter (SOM) decomposition rates and greenhouse gas production. In iron (Fe)‐rich soils, Fe(III) serve as a terminal electron acceptor, promoting anaerobic respiration SOM increasing pH. Current large‐scale models Arctic C cycling do not include Fe or pH interactions. Here,...
Dynamic pH change promoted by biogeochemical reactions in Arctic tundra soils can be a major control on the production and release of CO2 CH4, which contribute to rising global temperatures. Large quantities soil organic matter (SOM) these are susceptible microbial decomposition, leading changes during permafrost thaw. Soil buffering capacity (β) modulates extent but has not been thoroughly studied represented predictive ecosystem scale models soils. In this study, we generated titration...
Abstract. Rapid warming of Arctic ecosystems exposes soil organic matter (SOM) to accelerated microbial decomposition, potentially leading increased emissions carbon dioxide (CO2) and methane (CH4) that have a positive feedback on global warming. Current estimates the magnitude form from Earth system models include significant uncertainties, partially due oversimplified representation geochemical constraints decomposition. Here, we coupled modeling principles developed in different...
Abstract Soil respiration (R S ), the soil‐to‐atmosphere CO 2 flux that is a major component of global carbon cycle, strongly influenced by local soil temperature (T ) and water content (SWC). Regional to global‐scale R modelling thus requires this information at scales, but few high‐quality, wall‐to‐wall (global) T SWC data exist. As result, such efforts commonly use air monthly precipitation (P m as surrogate predictors, their site‐scale accuracy potential bias are unknown. Here, we used...
Abstract. Soil organic carbon turnover to CO2 and CH4 is sensitive soil redox potential pH conditions. However, land surface models do not consider in the aqueous phase explicitly, thereby limiting their use for making predictions anoxic environments. Using recent data from incubations of Arctic soils, we extend Community Land Model with coupled nitrogen (CLM-CN) decomposition cascade include simple substrate turnover, fermentation, Fe(III) reduction, methanogenesis reactions, assess...
Abstract A large literature exists on mechanisms driving soil production of the greenhouse gases CO 2 and CH 4 . Although it is common knowledge that measurements obtained through field studies vs. laboratory incubations can diverge because vastly different conditions these environments, few have systematically examined patterns. These data are used to parameterize benchmark ecosystem- global-scale models, which then susceptible biases source data. Here, we examine how gas may be influenced...
An enzyme-explicit denitrification model with representations for pre- and de novo synthesized enzymes was developed to improve predictions of nitrous oxide (N2O) accumulations in soil emissions from the surface. The metabolic is based on dual-substrate utilization Monod growth kinetics. Enzyme synthesis/activation incorporated into each sequential reduction step regulate dynamics denitrifier population active enzyme pool, which controlled rate function. Parameterizations were observations...
Microbially explicit models may improve understanding and projections of carbon dynamics in response to future climate change, but their fidelity simulating global-scale soil heterotrophic respiration (RH ), a stringent test for biogeochemical models, has never been evaluated. We used statistical global RH products, as well 7821 daily site-scale measurements, evaluate the spatiotemporal performance one first-order decay model (CASA-CNP) two microbially (CORPSE MIMICS) that were forced by...
Adsorbed or solid-phase inorganic mercury [Hg(II)] is commonly assumed immobile less bioavailable for microbial uptake, although recent studies suggest that mineral-adsorbed Hg(II) at least partially available cell uptake and methylation. This study examined the adsorption of onto two reference minerals, hematite montmorillonite, evaluated methylation by a sulfate-reducing bacterium Desulfovibrio desulfuricans ND132 in laboratory incubations. Mineral-adsorbed on both montmorillonite was not...
Turnover of soil organic carbon (SOC) is strongly affected by a balance between mineral protection and microbial degradation. However, the mechanisms controlling heterogeneous preferential adsorption different types SOC remain elusive. In this work, humic substances (HSs) (MC) on clay (nontronite NAu-2) during microbial-mediated Fe redox cycling was determined using time-of-flight secondary ion mass spectrometry (ToF-SIMS). The results revealed that HSs pre-adsorbed NAu-2 would partially...
The coastal terrestrial-aquatic interface (TAI) is a highly dynamic system characterized by strong physical, chemical, and biological gradients. In particular, shifting soil redox conditions, due in part to water driver of carbon availability transformations across TAIs. However, one the important unknowns TAIs how saturation drives oxic anoxic shifts soils with different characteristics inundation regimes. Continuous monitoring field sites unexpectedly revealed that flooding caused...