A5020149446- Plant Water Relations and Carbon Dynamics
- Atmospheric and Environmental Gas Dynamics
- Plant responses to elevated CO2
- Photosynthetic Processes and Mechanisms
- Remote Sensing in Agriculture
- Climate variability and models
- Atmospheric chemistry and aerosols
- Atmospheric Ozone and Climate
- Land Use and Ecosystem Services
- Isotope Analysis in Ecology
- Plant Stress Responses and Tolerance
- Light effects on plants
- Tree-ring climate responses
- Algal biology and biofuel production
- Carbon Dioxide Capture Technologies
- Forest ecology and management
- Remote Sensing and Land Use
- Ecology and Vegetation Dynamics Studies
- Spectroscopy and Quantum Chemical Studies
- Geology and Paleoclimatology Research
- Fire effects on ecosystems
- Soil Carbon and Nitrogen Dynamics
- Spectroscopy and Laser Applications
- Plant and animal studies
- Plant nutrient uptake and metabolism
Carnegie Institution for Science
2015-2024
Newcastle upon Tyne Hospital
2024
Stanford University
1975-2022
National Renewable Energy Laboratory
2019
University of Twente
2015
CSIRO Manufacturing
2013
National Oceanic and Atmospheric Administration
1997-2011
NASA Earth Science
2011
Weizmann Institute of Science
1992-2011
Lawrence Berkeley National Laboratory
2011
Theory is developed to explain the carbon isotopic composition of plants. It shown how diffusion gaseous CO2 can significantly affect discrimination. The effects on discrimination by and carboxylation are integrated, yielding a simple relationship between ratio intercellular atmospheric partial pressures CO2. dark respiration photorespiration also considered, it suggested that they have relatively little effect other than via their p(CO2). various environmental factors such as light,...
Crop loss due to soil salinization is an increasing threat agriculture worldwide. This review provides overview of cellular and physiological mechanisms in plant responses salt. We place a time- tissue-dependent context ...Read More
Abstract The formulation of a revised land surface parameterization for use within atmospheric general circulation models (GCMs) is presented. model (SiB2) incorporates several significant improvements over the first version Simple Biosphere (SiB) described in Sellers et al. can be summarized as follows: (i) incorporation realistic canopy photosynthesis–conductance to describe simultaneous transfer CO2 and water vapor into out vegetation, respectively; (ii) satellite data, companion paper,...
Atmospheric general circulation models used for climate simulation and weather forecasting require the fluxes of radiation, heat, water vapor, momentum across land-atmosphere interface to be specified. These are calculated by submodels called land surface parameterizations. Over last 20 years, these parameterizations have evolved from simple, unrealistic schemes into credible representations global soil-vegetation-atmosphere transfer system as advances in plant physiological hydrological...
Leaf based models of net photosynthesis (An) and stomatal conductance (g) are often components whole plant, canopy regional primary productivity surface energy balance. Since C4 metabolism shows unique responses to environmental conditions species important agriculturally ecologically, a realistic accurate leaf model specific plants is needed. In this paper we develop simple for predicting An g from leaves that easily parameterised predicts many the responses. We derive...
Significance Global food and biofuel production their vulnerability in a changing climate are of paramount societal importance. However, current global model predictions crop photosynthesis highly uncertain. Here we demonstrate that new space-based observations chlorophyll fluorescence, an emission intrinsically linked to plant biochemistry, enable accurate, global, time-resolved measurement photosynthesis, which is not possible from any other remote vegetation measurement. Our results show...
The global distribution of C 3 and 4 plants is required for accurately simulating exchanges CO 2 , water, energy between the land surface atmosphere. It also important to know /C simulations carbon isotope composition atmospheric owing distinct fractionations displayed by each photosynthetic type. Large areas are spatial temporal mosaics both types. We developed an approach capturing this heterogeneity combining remote sensing products, physiological modeling, a crop fractions, national...
Quantifying the near-infrared light reflected by plant canopies improves our ability to estimate global photosynthesis.
Photosynthesis and respiration impart distinct isotopic signatures to the atmosphere that are used constrain global carbon source/sink estimates partition ecosystem fluxes. Increasingly, “Keeling plot” method is being determine isotope composition of (δ 13 C R ) in order better understand processes controlling discrimination. In this paper we synthesize emergent patterns δ by analyzing 146 Keeling plots constructed at 33 sites across North South America. interpret results from disparate...
Conventional gas-exchange techniques that measure the stomatal conductance and rate of CO2 assimilation leaves were combined with measurements carbon isotope composition in air passing over a leaf. Isotopic discrimination during uptake was determined from difference entering leaving leaf chamber. measured short term correlated strongly combusted material. Environmental conditions manipulated to alter relative influences carboxylation on isotopes by intact leaves. With C3 plants, increased as...
Forest ecosystems store approximately 45% of the carbon found in terrestrial ecosystems, but they are sensitive to climate-induced dieback. die-off constitutes a large uncertainty projections climate impacts on climate–ecosystem interactions, and carbon-cycle feedbacks. Current understanding physiological mechanisms mediating forest mortality limits ability model or project these threshold events. We report here direct situ study underlying recent widespread trembling aspen ( Populus...
The physiological response of terrestrial vegetation when directly exposed to an increase in atmospheric carbon dioxide (CO 2 ) concentration could result warming over the continents addition that due conventional CO “greenhouse effect.” Results from a coupled biosphere-atmosphere model (SiB2-GCM) indicate that, for doubled conditions, evapotranspiration will drop and air temperature tropical continents, amplifying changes resulting radiative effects. range responses surface uptake increased...
The goal of the Boreal Ecosystem‐Atmosphere Study (BOREAS) is to improve our understanding interactions between boreal forest biome and atmosphere in order clarify their roles global change. This overview paper describes science background motivations for BOREAS experimental design operations 1994 1996 field years. findings 83 papers this journal special issue are reviewed. In section 7, important scientific results project date summarized future research directions identified.
A decline in the carbon fertilization effect One source of uncertainty climate science is how (CFE) will contribute to mitigation anthropogenic change. Wang et al. explored temporal dynamics CFE on vegetation photosynthesis at global scale. There has been a over recent decades contribution photosynthesis, perhaps owing limiting effects plant nutrients such as nitrogen and phosphorus. This declining trend not adequately accounted for cycle models. thus limitations long-term change, future...