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Potential gross primary productivity of terrestrial vegetation from 1982-1990

Ranga B. Myneni, Sietse O. Los, Ghassem Asrar
1995 Geophysical Research Letters  
., unstressed) gross primary productivity of terrestrial vegetation from 1982 to 1990.  ...  The evolution of monthly gross primary productivity anomahes was similar to atmospheric CO2 growth rate during 1982-1990.  ...  standard deviation ' mean) of gross primary production from 1982-1990.  ... 
doi:10.1029/95gl02562 fatcat:xk47aks2pvedvb3iviiony5hzy

Prospects for improving savanna biophysical models by using multiple-constraints model-data assimilation methods

Damian J. Barrett, Michael J. Hill, Lindsay B. Hutley, Jason Beringer, Johnny H. Xu, Garry D. Cook, John O. Carter, Richard J. Williams
2005 Australian Journal of Botany  
Retrieval of model parameters and initial conditions by the assimilation scheme, using only one data type, led to poor representation of modelled plant-canopy production and ecosystem respiration fluxes  ...  Application of these techniques will not only help fill knowledge gaps in the carbon and water dynamics of savannas but will result in better information for decision support systems to solve natural-resource  ...  Acknowledgments The authors thank Ying Ping Wang  ... 
doi:10.1071/bt04139 fatcat:zozcq6mr7jfmhgjxw2m5nbhxdq

Global Validation of a Process-Based Model on Vegetation Gross Primary Production Using Eddy Covariance Observations

Dan Liu, Wenwen Cai, Jiangzhou Xia, Wenjie Dong, Guangsheng Zhou, Yang Chen, Haicheng Zhang, Wenping Yuan, Christopher Carcaillet
2014 PLoS ONE  
Gross Primary Production (GPP) is the largest flux in the global carbon cycle. However, large uncertainties in current global estimations persist.  ...  Global mean GPP estimated by the IBIS model was 107.5061.37 Pg C year 21 (mean value 6 standard deviation) across the vegetated area for the period 2000-2006, consistent with the results of the EC-LUE  ...  Acknowledgments This work used eddy covariance data acquired by the FLUXNET community; in particular, by the following networks: AmeriFlux (U.S.  ... 
doi:10.1371/journal.pone.0110407 pmid:25375227 pmcid:PMC4222824 fatcat:gpm3tbwjerfufgfyun5z5zblia

First assessment of the plant phenology index (PPI) for estimating gross primary productivity in African semi-arid ecosystems [article]

A. M. Abdi, N. Boke-Olen, H. Jin, L. Eklundh, T. Tagesson, V. Lehsten, J. Ardo
2019 arXiv   pre-print
We developed a PPI-based model estimating gross primary productivity (GPP) that accounts for canopy water stress, and compared it against three other Earth observation-based GPP models: the temperature  ...  The results of this study show that a PPI-based GPP model is a promising tool for the estimation of GPP in the semi-arid ecosystems of Africa.  ...  The authors would like to thank the reviewers for their time in providing detailed and constructive comments that improved the quality of the manuscript.  ... 
arXiv:1902.08058v1 fatcat:jt67qo3t3rfgtfbk3iiu7vohte

Optimum temperature for photosynthesis: from leaf- to ecosystem-scale

Yongwen Liu
2020 Science Bulletin  
Acknowledgments This work was supported by the National Natural Science Foundation of China (41701089) and the Youth Innovation Promotion Association, Chinese Academy of Sciences, China (2019074).  ...  This work used eddy covariance measurement datasets of half-hourly gross primary productivity along with half-hourly air temperature observations, satellite-derived proxies of gross primary productivity  ...  Here, the daytime air temperature is represented by daily maximum air temperature, and the gross primary productivity is represented by dailyaccumulated gross primary productivity.  ... 
doi:10.1016/j.scib.2020.01.006 fatcat:qllvdfklxjdkbcdokzsgki34i4

Simultaneous assimilation of satellite and eddy covariance data for improving terrestrial water and carbon simulations at a semi-arid woodland site in Botswana

T. Kato, M. Scholze, W. Knorr, E. Veenendaal, T. Kaminski, J. Kattge, N. Gobron
2012 Biogeosciences Discussions  
The mean uncertainty reduction (relative to the prior) over all parameters is 14.9 % for the simultaneous assimilation of LHF and FAPAR, 8.5 % for assimilating LHF only, and 6.1 % for assimilating FAPAR  ...  Here, we use the Carbon Cycle Data Assimilation System (CCDAS) to investigate the key parameters controlling ecological and hydrological activities for a semi-arid savanna woodland site in Maun, Botswana  ...  This study was supported by the Postdoctoral Fellowships for Research Abroad, Japan Society for the Promotion of Science, the Ministry of Education, Science, Culture, Sports and Technology of Japan, and  ... 
doi:10.5194/bgd-9-3615-2012 fatcat:tttxui3h7zaklmjw7dqsocfemi

Seasonal variation of carbon fluxes in a sparse savanna in semi arid Sudan

Jonas Ardö, Meelis Mölder, Bashir Awad El-Tahir, Hatim Abdalla Mohammed Elkhidir
2008 Carbon Balance and Management  
This causes large variability in net ecosystem exchange and in vegetation productivity, the subsistence basis for a major part of the rural population in Sahel.  ...  of the carbon budget of this grass land/sparse savanna site in semi arid Sudan.  ...  Acknowledgements Economic support was provided by the Swedish Science Council (ref. no. 2004-3888) and by EU through the CARBOAFRICA project.  ... 
doi:10.1186/1750-0680-3-7 pmid:19046418 pmcid:PMC2632635 fatcat:y6hfuxs3e5fxdo4a2fvl746cbe

MODIS vegetation products as proxies of photosynthetic potential along a gradient of meteorologically and biologically driven ecosystem productivity

Natalia Restrepo-Coupe, Alfredo Huete, Kevin Davies, James Cleverly, Jason Beringer, Derek Eamus, Eva van Gorsel, Lindsay B. Hutley, Wayne S. Meyer
2016 Biogeosciences  
satellite products, including VIs, gross primary productivity (GPP<sub>MOD</sub>), leaf area index (LAI<sub>MOD</sub>), and fraction of photosynthetic active radiation (fPAR<sub>MOD</sub>).  ...  </strong> A direct relationship between gross ecosystem productivity (GEP) estimated by the eddy covariance (EC) method and Moderate Resolution Imaging Spectroradiometer (MODIS) vegetation indices (VIs  ...  We show our respect and acknowledge the people, the traditional custodians of the land, of elders past and present of the Arrernte nation at Alice Springs, the Wiradjuri people at Tumbarumba, the Meru  ... 
doi:10.5194/bg-13-5587-2016 fatcat:4wjo5ip5urdjjjsfueytxt7cgy

A continuous measure of gross primary production for the conterminous United States derived from MODIS and AmeriFlux data

Jingfeng Xiao, Qianlai Zhuang, Beverly E. Law, Jiquan Chen, Dennis D. Baldocchi, David R. Cook, Ram Oren, Andrew D. Richardson, Sonia Wharton, Siyan Ma
2010 Remote Sensing of Environment  
Our GPP estimates provide a spatially and temporally continuous measure of gross primary production for the U.S. that is a highly constrained by eddy covariance flux data.  ...  With these estimates, we then examined the patterns, magnitude, and interannual variability of GPP. We estimated a gross carbon uptake between 6.91 and 7.33 Pg C yr − 1 for the conterminous U.S.  ...  Acknowledgements This research was partly supported by the National Science Foundation (NSF) Carbon and Water Program (EAR-0630319). We  ... 
doi:10.1016/j.rse.2009.10.013 fatcat:duxinq4ccnarzbxuslay6o6rq4

Variability and recent trends in the African terrestrial carbon balance

P. Ciais, S.-L. Piao, P. Cadule, P. Friedlingstein, A. Chédin
2009 Biogeosciences  
The land use flux alone is estimated to be a source of 0.13 Pg C yr −1 caused by deforestation.  ...  Overall, we found that the African net terrestrial carbon balance (Net Biome Productivity, NBP) increased from a net CO 2 source to the atmosphere of 0.14 Pg C yr −1 in the 1980s to a net sink of 0.15  ...  Piao was supported by the Foundation for the Author of National Excellent Doctoral Dissertation of PR China (FANEDD-200737). Edited by: J.  ... 
doi:10.5194/bg-6-1935-2009 fatcat:pjljf2srb5cmhlihiyyusyjw2m

Simultaneous assimilation of satellite and eddy covariance data for improving terrestrial water and carbon simulations at a semi-arid woodland site in Botswana

T. Kato, W. Knorr, M. Scholze, E. Veenendaal, T. Kaminski, J. Kattge, N. Gobron
2013 Biogeosciences  
The mean uncertainty reduction (relative to the prior) over all parameters is 14.9% for the simultaneous assimilation of LHF and FAPAR, 8.5% for assimilating LHF only, and 6.1% for assimilating FAPAR only  ...  Here, we use the Carbon Cycle Data Assimilation System (CCDAS) to investigate the key parameters controlling ecological and hydrological activities for a semi-arid savanna woodland site in Maun, Botswana  ...  This study was supported by the Postdoctoral Fellowships for Research Abroad, Japan Society for the Promotion of Science, the Ministry of Education, Science, Culture, Sports and Technology of Japan, and  ... 
doi:10.5194/bg-10-789-2013 fatcat:zps7wqbbkvdyhfvg4w7rgbg77a

Estimation of gross primary production over the terrestrial ecosystems in China

Xianglan Li, Shunlin Liang, Guirui Yu, Wenping Yuan, Xiao Cheng, Jiangzhou Xia, Tianbao Zhao, Jinming Feng, Zhuguo Ma, Mingguo Ma, Shaomin Liu, Jiquan Chen (+11 others)
2013 Ecological Modelling  
However, a high proportion of sparsely vegetated area in China resulted in the overall low GPP.  ...  The inter-annual variability in GPP was significantly influenced by air temperature (R 2 = 0.66, P < 0.05), precipitation (R 2 = 0.71, P < 0.05), and normalized difference vegetation index (NDVI) (R 2  ...  We also acknowledge the Coordinated Observations and Integrated Research over Arid and Semi-arid China (COIRAS) (lead by Key Laboratory of Regional Climate-Environment Research for the Temperate East Asia  ... 
doi:10.1016/j.ecolmodel.2013.03.024 fatcat:fr5gstwdc5c4hc7geqmomtsabm

Evaluation of satellite based indices for gross primary production estimates in a sparse savanna in the Sudan

M. Sjöström, J. Ardö, L. Eklundh, B. A. El-Tahir, H. A. M. El-Khidir, M. Hellström, P. Pilesjö, J. Seaquist
2009 Biogeosciences  
One of the more frequently applied methods for integrating controls on primary production through satellite data is the Light Use Efficiency (LUE) approach.  ...  Results show a strong correlation between vegetation indices and gross primary production (GPP), demonstrating the significance of vegetation indices for deriving information on primary production with  ...  We appreciate the assistance from the Agricultural Research Corporation (ARC) personnel in El Obeid and the assistance from the people of Demokeya during fieldwork.  ... 
doi:10.5194/bg-6-129-2009 fatcat:fxk3e2d6wra5zmhfwlatyf3aly

Joint control of terrestrial gross primary productivity by plant phenology and physiology

Jianyang Xia, Shuli Niu, Philippe Ciais, Ivan A. Janssens, Jiquan Chen, Christof Ammann, Altaf Arain, Peter D. Blanken, Alessandro Cescatti, Damien Bonal, Nina Buchmann, Peter S. Curtis (+29 others)
2015 Proceedings of the National Academy of Sciences of the United States of America  
Terrestrial gross primary productivity (GPP) varies greatly over time and space.  ...  The variability in carbon sequestration is partially caused by variation in terrestrial gross primary productivity (GPP) (2), which is the cumulative rate over time of gross plant Significance Terrestrial  ...  We thank the anonymous reviewers and Steven Running for their constructive comments and suggestions, and Lianhong Gu and Ying-Ping Wang for their help in data analyses.  ... 
doi:10.1073/pnas.1413090112 pmid:25730847 pmcid:PMC4352779 fatcat:24txdk34qvb4fl6glc5lxj7yey

Variability and recent trends in the African carbon balance

P. Ciais, S.-L. Piao, P. Cadule, P. Friedlingstein, A. Chédin
2008 Biogeosciences Discussions  
The main spatial pattern of interannual variability in NBP and in gross carbon fluxes is related with ENSO, with dryer conditions prevailing over 15 savannas during El Niño and wetter conditions over forests  ...  Overall, we found 5 that the African net carbon balance (Net Biome Productivity, NBP) increased from a net carbon source of −0.14 Pg C yr −1 in the 1980s to a net carbon sink of 0.15 Pg C yr −1 in the  ...  Mougin for their very  ... 
doi:10.5194/bgd-5-3497-2008 fatcat:tohnruy2ybgr5bpqzcdijnexca
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