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An NDVI-Based Vegetation Phenology Is Improved to be More Consistent with Photosynthesis Dynamics through Applying a Light Use Efficiency Model over Boreal High-Latitude Forests

Siheng Wang, Lifu Zhang, Changping Huang, Na Qiao
2017 Remote Sensing  
Results show that VI-based phenology is improved towards tracking seasonal GPP changes more precisely after applying the light use efficiency model compared to raw NDVI or APAR, especially over ENF.  ...  applying a light use efficiency model.  ...  Results of the present study show that VI-based phenology is improved towards better tracking seasonal photosynthesis (GPP) dynamics through applying a VI-based LUE model.  ... 
doi:10.3390/rs9070695 fatcat:mlptnlcjgjfjfalcvejwgtrgda

Satellite chlorophyll fluorescence measurements reveal large-scale decoupling of photosynthesis and greenness dynamics in boreal evergreen forests

Sophia Walther, Maximilian Voigt, Tea Thum, Alemu Gonsamo, Yongguang Zhang, Philipp Köhler, Martin Jung, Andrej Varlagin, Luis Guanter
2016 Global Change Biology  
Although the maps in Fig. 4c,d show a tendency of SIF 388 of SIF to the light-use efficiency of boreal forests 417 418 Following a production-efficiency model (Monteith, 1972), SIF and GPP can be 419  ...  of photosynthesis in mid-to-high latitude 154 forests.  ... 
doi:10.1111/gcb.13200 pmid:26683113 fatcat:3fmrwb2zb5bnbkbesuy6dtprvq

Satellite-based modeling of gross primary production in an evergreen needleleaf forest

Xiangming Xiao, David Hollinger, John Aber, Mike Goltz, Eric A. Davidson, Qingyuan Zhang, Berrien Moore
2004 Remote Sensing of Environment  
In this paper, we develop a new, satellite-based Vegetation Photosynthesis Model (VPM) to estimate the seasonal dynamics and interannual variation of GPP of evergreen needleleaf forests.  ...  The VPM model uses two improved vegetation indices (Enhanced Vegetation Index (EVI), Land Surface Water Index (LSWI)).  ...  The modeling study was supported by research grants from NASA Interdisciplinary Science Program (NAG5-10135) and Land Cover and Land Use Change Program (NAG5-11160).  ... 
doi:10.1016/j.rse.2003.11.008 fatcat:6ehjc77yvzdo7baspxg3z4kpni

Detecting Inter-Annual Variations in the Phenology of Evergreen Conifers Using Long-Term MODIS Vegetation Index Time Series

Laura Ulsig, Caroline Nichol, Karl Huemmrich, David Landis, Elizabeth Middleton, Alexei Lyapustin, Ivan Mammarella, Janne Levula, Albert Porcar-Castell
2017 Remote Sensing  
This study investigates the potential of a Photochemical Reflectance Index (PRI), which has been linked to vegetation light use efficiency, to improve the accuracy of MODIS-based estimates of phenology  ...  Long-term observations of vegetation phenology can be used to monitor the response of terrestrial ecosystems to climate change.  ...  We further offer thanks to Pasi Kolari for his support in preparing the flux dataset used in this analysis.  ... 
doi:10.3390/rs9010049 fatcat:gnopydcraffcnn3wochtbhbqtq

GEOCLIM: A global climatology of LAI, FAPAR, and FCOVER from VEGETATION observations for 1999–2010

Aleixandre Verger, Frédéric Baret, Marie Weiss, Iolanda Filella, Josep Peñuelas
2015 Remote Sensing of Environment  
The GEOCLIM data set is demonstrated to be 23 consistent, both spatially and temporally.  ...  9 Land-surface modelling would benefit significantly from improved characterisation of the seasonal 10 variability of vegetation at a global scale.  ...  Improved 492 monitoring of vegetation dynamics at very high latitudes: A new method using MODIS NDVI. M., Verger, A., Diouf, A., Baret, F., & Samimi, C. (2014).  ... 
doi:10.1016/j.rse.2015.05.027 fatcat:4s2itlhasraqbfxwrpdsurvh6q

Remote Sensing of Environmental Changes in Cold Regions: Methods, Achievements and Challenges

Jinyang Du, Jennifer D. Watts, Lingmei Jiang, Hui Lu, Xiao Cheng, Claude Duguay, Mary Farina, Yubao Qiu, Youngwook Kim, John S. Kimball, Paolo Tarolli
2019 Remote Sensing  
Cold regions, including high-latitude and high-altitude landscapes, are experiencing profound environmental changes driven by global warming.  ...  With the advance of earth observation technology, remote sensing has become increasingly important for detecting, monitoring, and understanding environmental changes over vast and remote regions.  ...  The efficiency parameter is more difficult to model and can vary based on vegetation type, water limitations, and light conditions [220] .  ... 
doi:10.3390/rs11161952 fatcat:63wghdyherdo3cyxasqpcbrz3m

MODELING GROSS PRIMARY PRODUCTION OF AN EVERGREEN NEEDLELEAF FOREST USING MODIS AND CLIMATE DATA

Xiangming Xiao, Qingyuan Zhang, David Hollinger, John Aber, Berrien Moore
2005 Ecological Applications  
In this study we developed and validated a satellite-based vegetation photosynthesis model (VPM; GPP = 6, X FAPAP" X PAR) that incorporates improved vegetation indices derived from the moderate resolution  ...  The enhanced vegetation index (EVI) better correlated with the seasonal dynamics of GPP than did the nornlalized difference vegetation index (NDVI).  ...  John Lee, Holly Hughes, arid Jeremiah Walsh provided expert assistance with the Howland Forest multi-year CO, flux and climate data set.  ... 
doi:10.1890/04-0470 fatcat:guzjmu3kwbdjlegc6tdjdwpjaq

Spatiotemporal Dynamics in Vegetation GPP over the Great Khingan Mountains Using GLASS Products from 1982 to 2015

Ling Hu, Wenjie Fan, Huazhong Ren, Suhong Liu, Yaokui Cui, Peng Zhao
2018 Remote Sensing  
Another method of vegetation monitoring is based on remotely sensed GPP models. The major approach to this method is to employ the maximum light use efficiency (LUE) [23] [24] [25] [26] [27] [28] .  ...  To date, only a few studies [10] have reported on how the GPP of boreal forests vary with climate.  ...  Author Contributions: All authors contributed significantly to this manuscript.  ... 
doi:10.3390/rs10030488 fatcat:nd47aokam5au3ox3rlgkzavgpi

Investigation of North American vegetation variability under recent climate: A study using the SSiB4/TRIFFID biophysical/dynamic vegetation model

Zhengqiu Zhang, Yongkang Xue, Glen MacDonald, Peter M. Cox, G. James Collatz
2015 Journal of Geophysical Research - Atmospheres  
With more observational data availability, more studies with different models and focusing on different regions will be possible and are necessary to achieve comprehensively understanding of the vegetation  ...  at seasonal to decadal scales over North America (NA) to assess a 2-D biophysical model/dynamic vegetation model's (SSiB4/TRIFFID) ability to simulate these characteristics for the past 60 years (1948  ...  The data for this paper is available at http://www.sscnet.ucla.edu/geog/wamme/ NA_ClimVeg/NA_ClimVeg1948_08.tar.gz.  ... 
doi:10.1002/2014jd021963 fatcat:v2m7wsyyz5extostdipr4uj3ea

Multi-model analysis of terrestrial carbon cycles in Japan: limitations and implications of model calibration using eddy flux observations

K. Ichii, T. Suzuki, T. Kato, A. Ito, T. Hajima, M. Ueyama, T. Sasai, R. Hirata, N. Saigusa, Y. Ohtani, K. Takagi
2010 Biogeosciences  
eddy flux sites in Japan and (2) spatial simulations for Japan with a default model (based on original settings) and a modified model (based on model parameter tuning using eddy flux data).  ...  Terrestrial biosphere models show large differences when simulating carbon and water cycles, and reducing these differences is a priority for developing more accurate estimates of the condition of terrestrial  ...  This study was financially supported by the A3 Foresight Program (CarboEastAsia: Capacity building among ChinaFlux, JapanFlux, and KoFlux to cope with climate change protocols by synthesizing measurement  ... 
doi:10.5194/bg-7-2061-2010 fatcat:6crsx2wwdzeqdcklvj44sgouqa

A remotely sensed pigment index reveals photosynthetic phenology in evergreen conifers

John A. Gamon, K. Fred Huemmrich, Christopher Y. S. Wong, Ingo Ensminger, Steven Garrity, David Y. Hollinger, Asko Noormets, Josep Peñuelas
2016 Proceedings of the National Academy of Sciences of the United States of America  
Noormets, Asko; and Peñuelas, Josep, "A remotely sensed pigment index reveals photosynthetic phenology in evergreen conifers" (2016). Papers in Natural Resources. 585.  ...  For example, the MOD17 algorithm based on the light-use efficiency (LUE) model (10) states that daily GPP, or gross primary production, is a product of absorbed radiation (APAR) and the Significance  ...  phenology, particularly for evergreens that have been difficult to measure from satellites using more conventional vegetation indices (e.g., the NDVI).  ... 
doi:10.1073/pnas.1606162113 pmid:27803333 pmcid:PMC5135292 fatcat:oixpvh5czjhlnkll2oec6dgdfu

Environmental controls on the greening of terrestrial vegetation across northern Eurasia

P. Dass, M. A. Rawlins, J. S. Kimball, Y. Kim
2015 Biogeosciences Discussions  
For the period 1982–2008 we find that GPP, estimated using ensemble satellite NDVI (Normalized Difference Vegetation Index) observations from GIMMS3g and VIP datasets, is most sensitive to temperature,  ...  Warming over the period analyzed, even without a sustained increase in precipitation, led to a significant GPP increase over 67.3 % of the region.  ...  This research was supported through NASA grant NNX11AR16G and the Permafrost Carbon Network (http://www.permafrostcarbon.org/), funded by the National Science Foundation.  ... 
doi:10.5194/bgd-12-9121-2015 fatcat:nzgxb7edxrhnnhmk4ac2nzntny

Constraining modelled global vegetation dynamics and carbon turnover using multiple satellite observations

Matthias Forkel, Markus Drüke, Martin Thurner, Wouter Dorigo, Sibyll Schaphoff, Kirsten Thonicke, Werner von Bloh, Nuno Carvalhais
2019 Scientific Reports  
Using a machine learning approach, we found that remaining errors in simulated forest carbon turnover can be explained with bioclimatic variables.  ...  This demonstrates the need to improve model formulations for climate effects on vegetation turnover and mortality despite the apparent successful constraint of simulated vegetation dynamics with multiple  ...  M.F. performed this work at his previous affiliations TU Wien and MPI for Biogeochemistry, and by using the HPC infrastructure as a visiting scientist at PIK Potsdam.  ... 
doi:10.1038/s41598-019-55187-7 pmid:31822728 pmcid:PMC6904745 fatcat:f4gn32uyd5d6fl33sclkqeuy6i

Vegetation Dynamics Enhancing Long-Term Climate Variability Confirmed by Two Models

Christine Delire, Nathalie de Noblet-Ducoudré, Adriana Sima, Isabelle Gouirand
2011 Journal of Climate  
The realistic modeled vegetation-atmosphere feedback gives us confidence that the vegetation dynamics enhancement of the long-term climate variability is not a model artifact.  ...  The models simulate feedbacks of the right sign and order of magnitude over large regions of the globe: positive temperature feedback in the mid-to high latitudes, negative feedback in semiarid regions  ...  We are also grateful to the developers of the free NCL software used for the figures.  ... 
doi:10.1175/2010jcli3664.1 fatcat:msfp2e6ovjdgnlob7dhzhyg5im

Assessing land cover change resulting from large surface mining development

Rasim Latifovic, Kostas Fytas, Jing Chen, Jacek Paraszczak
2005 International Journal of Applied Earth Observation and Geoinformation  
The primary impact was assessed using an information extraction method applied to two LANDSAT scenes.  ...  A remote sensing based land cover change assessment methodology is presented and applied to a case study of the Oil Sands Mining Development in Athabasca, Alta., Canada.  ...  Acknowledgements We would like to thank to Bert Guindon from the Canadian Centre of Remote Sensing for his useful input and review during manuscript preparation.  ... 
doi:10.1016/j.jag.2004.11.003 fatcat:w5iucs3ejre67pqt7xclzats3q
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