A5020584946- Peatlands and Wetlands Ecology
- Atmospheric and Environmental Gas Dynamics
- Plant Water Relations and Carbon Dynamics
- Coastal wetland ecosystem dynamics
- Remote Sensing in Agriculture
- Hydrology and Watershed Management Studies
- Constructed Wetlands for Wastewater Treatment
- Fire effects on ecosystems
- Species Distribution and Climate Change
- Climate variability and models
- Climate change and permafrost
- Soil Carbon and Nitrogen Dynamics
- Urban Heat Island Mitigation
- Remote Sensing and LiDAR Applications
- Water-Energy-Food Nexus Studies
- Crop Yield and Soil Fertility
- Bioenergy crop production and management
- Methane Hydrates and Related Phenomena
- Hydrocarbon exploration and reservoir analysis
- Cryospheric studies and observations
- Plant responses to elevated CO2
- Meteorological Phenomena and Simulations
- Land Use and Ecosystem Services
- Tree-ring climate responses
- Arctic and Antarctic ice dynamics
University of California, Berkeley
2015-2024
Berkeley College
2018-2024
San Diego State University
2000-2013
United States Global Change Research Program
2003
California State University, San Marcos
2000
Abstract Agricultural drainage of organic soils has resulted in vast soil subsidence and contributed to increased atmospheric carbon dioxide (CO 2 ) concentrations. The Sacramento‐San Joaquin Delta California was drained over a century ago for agriculture human settlement since experienced rates that are among the highest world. It is recognized unsustainable long‐term, help reverse capture (C) there an interest restoring agricultural land‐use types flooded conditions. However, flooding may...
The Mediterranean-type oak/grass savanna of California is composed widely spaced oak trees with understory grasses. These regions are interspersed large areas more open grasslands. ability remotely sensed data (with various spatial resolutions) to monitor the phenology in these water-limited savannas and grasslands explored over 2012–2015 timeframe using from Landsat (30 m), MODerate resolution Imaging Spectroradiometer (MODIS – gridded 500 Visible Infrared Radiometer Suite (VIIRS m) data....
Abstract We present 6.5 years of eddy covariance measurements fluxes methane ( F CH4 ) and carbon dioxide CO2 from a flooded rice paddy in Northern California, USA. A pronounced warming trend throughout the study associated with drought record high temperatures strongly influenced (C) budgets provided insights into biophysical controls . Wavelet analysis indicated that photosynthesis (gross ecosystem production, GEP) induced diel pattern , but soil temperature T s modulated its amplitude....
Abstract Methane (CH 4 ) exchange in wetlands is complex, involving nonlinear asynchronous processes across diverse time scales. These and scales are poorly characterized at the whole‐ecosystem level, yet crucial for accurate representation of CH process models. We used a combination wavelet analysis information theory to analyze interactions between flux biophysical drivers two restored Northern California from hourly seasonal scales, explicitly questioning assumptions linear, synchronous,...
Abstract Globally, soils store two to three times as much carbon currently resides in the atmosphere, and it is critical understand how soil greenhouse gas (GHG) emissions uptake will respond ongoing climate change. In particular, soil‐to‐atmosphere CO 2 flux, commonly though imprecisely termed respiration ( R S ), one of largest fluxes Earth system. An increasing number high‐frequency measurements (typically, from an automated system with hourly sampling) have been made over last decades;...
Inundated wetlands can potentially sequester substantial amounts of soil carbon (C) over the long-term because slow decomposition and high primary productivity, particularly in climates with long growing seasons. Restoring such may provide one several effective negative emission technologies to remove atmospheric CO2 mitigate climate change. However, there remains considerable uncertainty whether these heterogeneous ecotones are consistent net C sinks what degree restoration management...
Alfalfa is the most widely grown forage crop worldwide and thought to be a significant carbon sink due high productivity, extensive root systems, nitrogen-fixation. However, these conditions may increase nitrous oxide (N2O) emissions thus lowering climate change mitigation potential. We used suite of long-term automated instrumentation satellite imagery quantify patterns drivers greenhouse gas fluxes in continuous alfalfa agroecosystem California. show that this system was large N2O source...
Abstract There are few observational studies measuring the ecosystem‐scale productivity effects of changes in incident diffuse photosynthetically active radiation (PAR ), especially related to wildfire smoke. Climate change‐induced increases duration and intensity fire conditions have made smoke a common occurrence across western North America, with largely unquantified ecosystem feedbacks. Under equivalent amounts radiation, increased atmospheric particulate matter could lead boost as...
Abstract Restored wetlands are a complex mosaic of open water and new old emergent vegetation patches, where multiple environmental biological drivers contribute to the measured heterogeneity in methane (CH 4 ) flux. In this analysis, we replicated measurements CH flux using eddy covariance technique at three tower locations within same wetland site parse spatiotemporal variability contributed by large‐scale seasonal variations climate phenology short‐term footprint movement over water....
Abstract Temperate freshwater wetlands are among the most productive terrestrial ecosystems, stimulating interest in using restored as biological carbon sequestration projects for greenhouse gas reduction programs. In this study, we used eddy covariance technique to measure surface energy fluxes from a constructed, impounded wetland during two annual periods that were 8 years apart: 2002–2003 and 2010–2011. During 2010–2011, measured methane (CH 4 ) quantify atmospheric mass balance its...
Abstract Gross primary productivity (GPP) is the largest flux in global carbon cycle and satellite‐based GPP estimates have long been used to study trends interannual variability of GPP. With recent updates geostationary satellites, we can now explore diurnal at a comparable spatial resolution polar‐orbiting satellites temporal frequencies eddy covariance (EC) tower sites. We observations from Advanced Baseline Imager on Geostationary Operational Environmental Satellite‐R series (GOES‐R)...
Eddy covariance has been the gold standard used to quantify on-farm crop water use and validate evapotranspiration remote sensing models, but it comes with a high cost. Development of surface renewal allowed cheaper implementations, still requires complex data processing. Additionally, thermocouple in this method is vulnerable breakage. With depleting resources western U.S., there needs be that cost-effective simple across wide range crops. Here, we employed variance-Bowen ratio approach at...
Abstract Wetlands and flooded peatlands can sequester large amounts of carbon (C) have high greenhouse gas mitigation potential. There is growing interest in financing wetland restoration using C markets; however, this requires careful accounting both CO 2 CH 4 exchange at the ecosystem scale. Here we present a new model, PEPRMT model (Peatland Ecosystem Photosynthesis Respiration Methane Transport), which consists hierarchy biogeochemical models designed to estimate restored managed...