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Evaluating spatial and temporal patterns of MODIS GPP over the conterminous U.S. against flux measurements and a process model

Fangmin Zhang, Jing M. Chen, Jiquan Chen, Christopher M. Gough, Timothy A. Martin, Danilo Dragoni
2012 Remote Sensing of Environment  
Gross primary productivity (GPP) quantifies the photosynthetic uptake of carbon by ecosystems and is an important component of the terrestrial carbon cycle.  ...  In this paper, the MODIS GPP algorithm using the LUE approach and the Boreal Ecosystem Productivity Simulator (BEPS) based on the FvCB model in which a sunlit and shaded leaf separation scheme is evaluated  ...  We are greatly indebted to the principle investigators and research teams of the sites selected for our study.  ... 
doi:10.1016/j.rse.2012.06.023 fatcat:ipbtt6fs25dcplqa4gkc6sidgi

Improved estimates of global terrestrial photosynthesis using information on leaf chlorophyll content

Xiangzhong Luo, Holly Croft, Jing M. Chen, Liming He, Trevor F. Keenan
2019 Global Change Biology  
The terrestrial biosphere plays a critical role in mitigating climate change by absorbing anthropogenic CO 2 emissions through photosynthesis.  ...  The rate of photosynthesis is determined jointly by environmental variables and the intrinsic photosynthetic capacity of plants (i.e. maximum carboxylation  ...  ACKNOWLEDGEMENTS XL, HC, JMC and LH were supported by a Discovery Grant and a Strategic Grant from the Natural Science and Engineering Council of Canada.  ... 
doi:10.1111/gcb.14624 fatcat:5tchx2c5bnhq5exz75jfmdciqe

Global parameterization and validation of a two-leaf light use efficiency model for predicting gross primary production across FLUXNET sites

Yanlian Zhou, Xiaocui Wu, Weimin Ju, Jing M. Chen, Shaoqiang Wang, Huimin Wang, Wenping Yuan, T. Andrew Black, Rachhpal Jassal, Andreas Ibrom, Shijie Han, Junhua Yan (+22 others)
2016 Journal of Geophysical Research - Biogeosciences  
Recently, a two-leaf light use efficiency (TL-LUE) model was developed to simulate GPP separately for sunlit and shaded leaves and has been shown to outperform the big-leaf MOD17 model at six FLUX sites  ...  Light use efficiency (LUE) models are widely used to simulate gross primary production (GPP).  ...  Introduction Gross primary productivity (GPP) is a key component of the terrestrial carbon cycle and a principal indicator for biosphere carbon fluxes [Zhang et al., 2009; Yuan et al., 2010] .  ... 
doi:10.1002/2014jg002876 fatcat:u6ha7vhponalzeguif3tl5oasm

Evaluating Parameter Adjustment in the MODIS Gross Primary Production Algorithm Based on Eddy Covariance Tower Measurements

Jing Chen, Huifang Zhang, Zirui Liu, Mingliang Che, Baozhang Chen
2014 Remote Sensing  
We then compared these estimates of the MOD17A2 product, by the MODIS algorithm with default parameters in the Biome Property Look-Up Table, and by a two-leaf Farquhar model.  ...  How well parameterization will improve gross primary production (GPP) estimation using the MODerate-resolution Imaging Spectroradiometer (MODIS) algorithm has been rarely investigated.  ...  , CAS, and -One Hundred Talents‖ program funded by the Chinese Academy of ciences. We acknowledge the agencies that supported the operations at the flux towers used here, which are part of FLUXNET.  ... 
doi:10.3390/rs6043321 fatcat:3fvr5ypyunhz3oqpzl2u6uiib4

Effects of foliage clumping on the estimation of global terrestrial gross primary productivity

Jing M. Chen, Gang Mo, Jan Pisek, Jane Liu, Feng Deng, Misa Ishizawa, Douglas Chan
2012 Global Biogeochemical Cycles  
1] Sunlit and shaded leaf separation proposed by Norman (1982) is an effective way to upscale from leaf to canopy in modeling vegetation photosynthesis.  ...  The Boreal Ecosystem Productivity Simulator (BEPS) makes use of this methodology, and has been shown to be reliable in modeling the gross primary productivity (GPP) derived from CO 2 flux and tree ring  ...  This provides an opportunity to conduct sunlit and shaded leaf photosynthesis modeling at the global scale in a meaningful way.  ... 
doi:10.1029/2010gb003996 fatcat:w7urqpsgfrbfxodb2lzv4eklmq

A Novel Diffuse Fraction-Based Two-Leaf Light Use Efficiency Model: An Application Quantifying Photosynthetic Seasonality across 20 AmeriFlux Flux Tower Sites

Hao Yan, Shao-Qiang Wang, Kai-Liang Yu, Bin Wang, Qin Yu, Gil Bohrer, Dave Billesbach, Rosvel Bracho, Faiz Rahman, Herman H. Shugart
2017 Journal of Advances in Modeling Earth Systems  
An Amazonian rainforest site (KM67) was used to calibrate the model by simulating the linear relationship between monthly canopy LUE and D f .  ...  This creates the need to differentiate the effects of direct and diffuse radiation when simulating terrestrial gross primary production (GPP).  ...  Acknowledgments We would like to thank the flux site investigators for providing their data through the AmeriFlux program (https://ameriflux.lbl.gov) of the Department of Energy Office of Science, and  ... 
doi:10.1002/2016ms000886 fatcat:zxo7ng6yinczfbtr77lxuqxv6a

Remote sensing of canopy light use efficiency in temperate and boreal forests of North America using MODIS imagery

Chaoyang Wu, Jing M. Chen, Ankur R. Desai, David Y. Hollinger, M. Altaf Arain, Hank A. Margolis, Christopher M. Gough, Ralf M. Staebler
2012 Remote Sensing of Environment  
The usefulness of this new LUE algorithm is further validated for the estimation of gross primary production (GPP) at these sites with an RMSE of 37.6 g C m − 2 month − 1 for all observations, which reflects  ...  These results are especially important for the evergreen species due to their limited variability in canopy greenness.  ...  This work used data from flux sites from both the AmeriFlux and Fluxnet-Canada and we appreciate the flux PIs providing these valuable data and helpful explanations.  ... 
doi:10.1016/j.rse.2011.11.012 fatcat:jceqv2y2xreurfup5crraevlfq

A process-based model of conifer forest structure and function with special emphasis on leaf lifespan

Colin P. Osborne, David J. Beerling
2002 Global Biogeochemical Cycles  
from sites across a wide climatic gradient.  ...  It will be of use in future research investigating controls on the contrasting distribution of ancient evergreen and deciduous forests between hemispheres, and their differential feedbacks on polar climate  ...  Betts, and V. Brovkin for their comments on the manuscript. We appreciate the assistance, helpful discussion, and advice provided by D.S. Ellsworth, S.T.  ... 
doi:10.1029/2001gb001467 fatcat:tki7x23lovevjjwdqsnhehonim

Evaluation of Clumping Effects on the Estimation of Global Terrestrial Evapotranspiration

Bin Chen, Xuehe Lu, Shaoqiang Wang, Jing M. Chen, Yang Liu, Hongliang Fang, Zhenhai Liu, Fei Jiang, Muhammad Altaf Arain, Jinghua Chen, Xiaobo Wang
2021 Remote Sensing  
Deciduous broadleaf forests are affected by leaf clumping most in Case III because they have both high LAI and low CI compared to other PFTs.  ...  Clumping index (CI) is a key canopy structural parameter, characterizing the extent to which leaf deviates from the random distribution.  ...  Acknowledgments: We acknowledged support from SHARCNET for the computational resources. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs13204075 fatcat:y3icl4jbyvgbhix2qdmp76t57i

Environmental controls over carbon dioxide and water vapor exchange of terrestrial vegetation

B.E Law, E Falge, L Gu, D.D Baldocchi, P Bakwin, P Berbigier, K Davis, A.J Dolman, M Falk, J.D Fuentes, A Goldstein, A Granier (+21 others)
2002 Agricultural and Forest Meteorology  
Abstract The objective of this research was to compare seasonal and annual estimates of CO 2 and water vapor exchange across sites in forests, grasslands, crops, and tundra that are part of an international  ...  loss integrated over the year (slopes = 3.4 g CO 2 /kg H 2 O for grasslands, 3.2 for deciduous broadleaf forests, 3.1 for crops, 2.4 for evergreen conifers, and 1.5 for tundra vegetation).  ...  Acknowledgements We thank the numerous scientists, students, and technicians involved in data collection and analysis at the FLUXNET sites; the agencies that fund the projects (European Union, US Department  ... 
doi:10.1016/s0168-1923(02)00104-1 fatcat:rjlkmodmdbaxzdxgzqj7p4362u

Integration of MODIS land and atmosphere products with a coupled-process model to estimate gross primary productivity and evapotranspiration from 1 km to global scales

Youngryel Ryu, Dennis D. Baldocchi, Hideki Kobayashi, Catharine van Ingen, Jie Li, T. Andy Black, Jason Beringer, Eva van Gorsel, Alexander Knohl, Beverly E. Law, Olivier Roupsard
2011 Global Biogeochemical Cycles  
Then we coupled atmospheric and canopy radiative transfer processes, with models that computed leaf photosynthesis, stomatal conductance and transpiration on the sunlit and shaded portions of the vegetation  ...  1] We propose the Breathing Earth System Simulator (BESS), an upscaling approach to quantify global gross primary productivity and evapotranspiration using MODIS with a spatial resolution of 1-5 km and  ...  Global maps of (a) gross primary productivity and (b) evapotranspiration. personal communication, 2010). The leaf area index of 0 in evergreen forests is unrealistic.  ... 
doi:10.1029/2011gb004053 fatcat:phdcw66gqndgpaaan37rd4xtgu

A dynamic global vegetation model for use with climate models: concepts and description of simulated vegetation dynamics

Gordon B. Bonan, Samuel Levis, Stephen Sitch, Mariana Vertenstein, Keith W. Oleson
2003 Global Change Biology  
In this paper, we describe an approach in which ecological concepts from a global vegetation dynamics model are added to the land component of a climate model to grow plants interactively.  ...  The model simulates global biogeography, net primary production, and dynamics of tundra, boreal forest, northern hardwood forest, tropical rainforest, and savanna ecosystems, which are consistent with  ...  The National Center for Atmospheric Research is sponsored by the National Science Foundation.  ... 
doi:10.1046/j.1365-2486.2003.00681.x fatcat:zxa4egxomreuxmep7j63b25uve

A Vegetation Index to Estimate Terrestrial Gross Primary Production Capacity for the Global Change Observation Mission-Climate (GCOM-C)/Second-Generation Global Imager (SGLI) Satellite Sensor

Juthasinee Thanyapraneedkul, Kanako Muramatsu, Motomasa Daigo, Shinobu Furumi, Noriko Soyama, Kenlo Nasahara, Hiroyuki Muraoka, Hibiki Noda, Shin Nagai, Takahisa Maeda, Masayoshi Mano, Yasuko Mizoguchi
2012 Remote Sensing  
To estimate global gross primary production (GPP), which is an important parameter for studies of vegetation productivity and the carbon cycle, satellite data are useful.  ...  Using the chlorophyll index and incoming PAR, GPP was successfully estimated from LANDSAT data for crops [41] using MODIS data for deciduous and evergreen forest sites [42] .  ...  We acknowledge JAXA for GLI data, the Land Processes (LP) DAAC for MODIS datasets and FLUXNET Network (AmeriFlux, Fluxnet-Canada and Asia flux) for supporting flux data.  ... 
doi:10.3390/rs4123689 fatcat:3bfuyecvdvbklaho4akayoteuu

Linking flux network measurements to continental scale simulations: ecosystem carbon dioxide exchange capacity under non-water-stressed conditions

KATHERINE E. OWEN, JOHN TENHUNEN, MARKUS REICHSTEIN, QUAN WANG, EVA FALGE, RALF GEYER, XIANGMING XIAO, PAUL STOY, CHRISTOF AMMANN, ALTAF ARAIN, MARC AUBINET, MIKA AURELA (+18 others)
2007 Global Change Biology  
The results from these selected sites are used to derive a new parameter and means for comparing empirical and physiologically based methods across all sites, regardless of ancillary data.  ...  Relatively sparse documentation of leaf area index Data additionally provided by: dynamics at flux tower sites is found to be a major difficulty in model inversion and flux interpretation.  ...  We would like to thank Martin Heimann for his comments and support of the modelling and three anonymous reviewers for their helpful remarks on the manuscript.  ... 
doi:10.1111/j.1365-2486.2007.01326.x fatcat:sfm3a23vurhsbhepxre3oy5bgu

Linking flux network measurements to continental scale simulations: ecosystem carbon dioxide exchange capacity under non-water-stressed conditions

KATHERINE E. OWEN, JOHN TENHUNEN, MARKUS REICHSTEIN, QUAN WANG, EVA FALGE, RALF GEYER, XIANGMING XIAO, PAUL STOY, CHRISTOF AMMANN, ALTAF ARAIN, MARC AUBINET, MIKA AURELA (+18 others)
2007 Global Change Biology  
The results from these selected sites are used to derive a new parameter and means for comparing empirical and physiologically based methods across all sites, regardless of ancillary data.  ...  Relatively sparse documentation of leaf area index Data additionally provided by: dynamics at flux tower sites is found to be a major difficulty in model inversion and flux interpretation.  ...  We would like to thank Martin Heimann for his comments and support of the modelling and three anonymous reviewers for their helpful remarks on the manuscript.  ... 
doi:10.1111/j.1365-2486.2006.01326.x fatcat:7pa6ul6q3jcs5pdjwulldnealq
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