A5088061513- Peatlands and Wetlands Ecology
- Coastal wetland ecosystem dynamics
- Soil Carbon and Nitrogen Dynamics
- Atmospheric and Environmental Gas Dynamics
- Fire effects on ecosystems
- Geology and Paleoclimatology Research
- Methane Hydrates and Related Phenomena
- Geochemistry and Geologic Mapping
- Soil Geostatistics and Mapping
- Isotope Analysis in Ecology
- Hydrocarbon exploration and reservoir analysis
- Climate change and permafrost
- Image Processing and 3D Reconstruction
- Soil and Unsaturated Flow
- Cryospheric studies and observations
- Soil erosion and sediment transport
- Marine and coastal ecosystems
- Geological and Geophysical Studies
- Climate variability and models
- Mercury impact and mitigation studies
- Geological Studies and Exploration
- Geological and Geochemical Analysis
- Materials Engineering and Processing
- Hydrology and Watershed Management Studies
- Oil Palm Production and Sustainability
Stanford University
2021-2025
Max Planck Institute for Biogeochemistry
2018-2023
Massachusetts Institute of Technology
2014-2022
Palo Alto University
2022
Lawrence Berkeley National Laboratory
2017-2021
Parsons (United States)
2014-2018
Singapore-MIT Alliance for Research and Technology
2016
Yale University
2009
Peatlands represent large terrestrial carbon banks. Given that most peat accumulates in boreal regions, where low temperatures and water saturation preserve organic matter, the existence of (sub)tropical regions remains enigmatic. Here we examined plant chemistry across a latitudinal transect from Arctic to tropics. Near-surface low-latitude has lower carbohydrate greater aromatic content than near-surface high-latitude peat, creating reduced oxidation state resulting recalcitrance. This...
Understanding the controls on amount and persistence of soil organic carbon (C) is essential for predicting its sensitivity to global change. The response may depend whether C unprotected, isolated within aggregates, or protected from decomposition by mineral associations. Here, we present a synthesis relative influence environmental factors partitioning among pools, abundance in each pool (mg g-1 soil), (as approximated radiocarbon abundance) relatively unprotected particulate mineral-bound...
Abstract Wetland methane (CH 4 ) emissions over the Boreal–Arctic region are vulnerable to climate change and linked feedbacks, yet understanding of their long-term dynamics remains uncertain. Here, we upscaled analysed two decades (2002–2021) wetland CH emissions, representing an unprecedented compilation eddy covariance chamber observations. We found a robust increasing trend (+8.9%) with strong inter-annual variability. The majority emission increases occurred in early summer (June July)...
Tropical peatlands now emit hundreds of megatons carbon dioxide per year because human disruption the feedbacks that link peat accumulation and groundwater hydrology. However, no quantitative theory has existed for how patterns storage release accompanying growth subsidence tropical are affected by climate disturbance. Using comprehensive data from a pristine peatland in Brunei Darussalam, we show rainfall flow determine shape parameter (the Laplacian surface elevation) specifies, under...
The question of why some types organic matter are more persistent while others decompose quickly in soils has motivated a large amount research recent years. Persistence is commonly characterized as turnover or mean residence time soil (SOM). However, and times ambiguous measures persistence, because they could represent the concept either age transit time. To disambiguate these concepts propose metric to assess SOM we calculated distributions for wide range carbon models. Furthermore, show...
Abstract. Radiocarbon is a critical constraint on our estimates of the timescales soil carbon cycling that can aid in identifying mechanisms stabilization and destabilization improve forecast response to management or environmental change. Despite wealth radiocarbon data have been reported over past 75 years, ability apply these global-scale questions limited by capacity synthesize compare measurements generated using variety methods. Here, we present International Soil Database (ISRaD;...
Abstract The magnitude of future emissions greenhouse gases from the northern permafrost region depends crucially on mineralization soil organic carbon (SOC) that has accumulated over millennia in these perennially frozen soils. Many recent studies have used radiocarbon ( 14 C) to quantify release this “old” SOC as CO 2 or CH 4 atmosphere dissolved and particulate (DOC POC) surface waters. We compiled ~1,900 C measurements 51 sites assess vulnerability thawing tundra, forest, peatland, lake,...
Abstract. Soil organic carbon (SOC) stabilization and destabilization has been studied intensively. Yet, the factors which control SOC content across scales remain unclear. Earlier studies demonstrated that soil texture geochemistry strongly affect content. However, those findings primarily rely on data from temperate regions where mineralogy, weathering status climatic conditions generally differ tropical subtropical regions. We investigated properties climate variables influencing...
Soil organic carbon (SOC) dynamics depend on soil properties derived from the geoclimatic conditions under which soils develop and are in many cases modified by land conversion. However, SOC stabilization responses of to use change not well constrained deeply weathered tropical soils, dominated less reactive minerals than those temperate regions. Along a gradient geochemically distinct parent materials, we investigated differences stocks (Δ14 C) turnover time across profile depth between...
Abstract Peatlands are some of the world’s most carbon-dense ecosystems and release substantial quantities greenhouse gases when degraded. However, conserving peatlands in many tropical areas is challenging due to limited knowledge their distribution. To address this, we surveyed soils plant communities Colombia’s eastern lowlands, where few have previously been described. We documented peat >40 cm thick at 51 more than 100 wetlands. use our data update a regional peatland classification,...
Abstract Peatlands contain a significant fraction of global soil carbon, but how these reservoirs will respond to the changing climate is still relatively unknown. A picture variations in peat organic matter chemistry aid our ability gauge peatland response climate. The goal this research test hypotheses that (a) carbohydrate content, an indicator reactivity, increase with latitude and decrease mean annual temperatures, (b) while aromatic recalcitrance, vary inversely, (c) elevation have...
Organic carbon (OC) association with soil minerals stabilizes OC on timescales reflecting the strength of mineral–C interactions. We applied ramped thermal oxidation to subsoil B horizons different associations separate according increasing temperature oxidation, i.e. activation energy. Generally, released at lower temperatures was richer in bioavailable forms like polysaccharides, while higher more aromatic. associated pedogenic oxides and had a narrow range 14 C content. By contrast,...
Abstract. The magnitude of carbon (C) loss to the atmosphere via microbial decomposition is a function amount C stored in soils, quality organic matter, and physical, chemical, biological factors that comprise environment for decomposition. decomposability commonly assessed by laboratory soil incubation studies measure greenhouse gases mineralized from soils under controlled conditions. Here, we introduce Soil Incubation Database (SIDb) version 1.0, compilation time series data incubations,...
Soil carbon has been measured for over a century in applications ranging from understanding biogeochemical processes natural ecosystems to quantifying the productivity and health of managed systems. Consolidating diverse soil datasets is increasingly important maximize their value, particularly with growing anthropogenic climate change pressures. In this progress report, we describe recent advances data led by International Carbon Network other networks. We highlight priority areas research...
Abstract Drainage canals associated with logging and agriculture dry out organic soils in tropical peatlands, thereby threatening the viability of long‐term carbon stores due to increased emissions from decomposition, fire, fluvial transport. In Southeast Asian which have experienced decades land use change, exact extent spatial distribution drainage are unknown. This has prevented regional‐scale investigation relationships between drainage, use, emissions. Here, we create first regional map...
Abstract. In the age of big data, soil data are more available and richer than ever, but – outside a few large survey resources they remain largely unusable for informing management understanding Earth system processes beyond original study. Data science has promised fully reusable research pipeline where from past studies used to contextualize new findings reanalyzed insight. Yet synthesis projects encounter challenges at all steps reuse pipeline, including unavailable labor-intensive...
Tropical peatlands are among the most carbon-dense ecosystems on Earth, and their water storage dynamics strongly control these carbon stocks. The hydrological functioning of tropical differs from that northern peatlands, which has not yet been accounted for in global land surface models (LSMs). Here, we integrated peat-specific hydrology modules into a LSM first time, by utilizing peatland-specific model structure adaptation (PEATCLSM) NASA Catchment Land Surface Model (CLSM). We developed...