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Investigating the Relationship between the Inter-Annual Variability of Satellite-Derived Vegetation Phenology and a Proxy of Biomass Production in the Sahel

Michele Meroni, Felix Rembold, Michel Verstraete, Rene Gommes, Anne Schucknecht, Gora Beye
2014 Remote Sensing  
However, there is limited knowledge about the relationship between vegetation biomass production and these variables at the regional scale.  ...  The consistency of the results and the actual link between remote sensing-derived phenological parameters and biomass production were evaluated using field measurements of aboveground herbaceous biomass  ...  Acknowledgments The authors thank Ferdinando Urbano and Ana Perez-Hoyos of the Joint Research Centre of the European Commission for their support in the preparation of land cover information.  ... 
doi:10.3390/rs6065868 fatcat:ubazklahjfbkdcmxoupdkebw3e

Remote sensing of vegetation dynamics in drylands: Evaluating vegetation optical depth (VOD) using AVHRR NDVI and in situ green biomass data over West African Sahel

Feng Tian, Martin Brandt, Yi Y. Liu, Aleixandre Verger, Torbern Tagesson, Abdoul A. Diouf, Kjeld Rasmussen, Cheikh Mbow, Yunjia Wang, Rasmus Fensholt
2016 Remote Sensing of Environment  
Finally, both VOD and NDVI well reflect the spatial and inter-annual dynamics of the in situ green biomass data; however, the seasonal metrics showing the highest degree of explained variance differ between  ...  temporal and spatial variability of in situ measured green biomass (herbaceous mass and woody plant foliage mass) in the semi-arid Senegalese Sahel.  ...  Aleixandre Verger is the recipient of a Juan de la Cierva postdoctoral fellowship from the Spanish Ministry of Science and Innovation.  ... 
doi:10.1016/j.rse.2016.02.056 fatcat:x34yqk3lgbgjrozeqbi47d5g7m

Assessing woody vegetation trends in Sahelian drylands using MODIS based seasonal metrics

Martin Brandt, Pierre Hiernaux, Kjeld Rasmussen, Cheikh Mbow, Laurent Kergoat, Torbern Tagesson, Yahaya Z. Ibrahim, Abdoulaye Wélé, Compton J. Tucker, Rasmus Fensholt
2016 Remote Sensing of Environment  
The authors thank everyone involved in collecting the ground data in Senegal, Mali, and Niger, especially the Centre de Suivi Ecologique (CSE) and the Observatory AMMA-CATCH.  ...  High spatial resolution satellite images were provided within the NextView license agreement.  ...  While annual herbaceous vegetation that is dominant in the Sahel impact inter-annual variability, the long-living woody stratum is found to contribute more to long-term trends in vegetation productivity  ... 
doi:10.1016/j.rse.2016.05.027 fatcat:jojsr3p2afdnpmxfjb2elj2jii

Trends in Woody and Herbaceous Vegetation in the Savannas of West Africa

Julius Y. Anchang, Lara Prihodko, Armel T. Kaptué, Christopher W. Ross, Wenjie Ji, Sanath S. Kumar, Brianna Lind, Mamadou A. Sarr, Abdoul A. Diouf, Niall P. Hanan
2019 Remote Sensing  
The linearity/non-linearity of the productivity–rainfall relationship and its impact on the interpretation of overall greening trends, and specific woody and herbaceous vegetation trends, is also examined  ...  relationship is used to infer changing herbaceous conditions between early and late periods of the time series.  ...  Acknowledgments: We acknowledge the contribution of our colleagues from the Centre de Suivi Ecologique (CSE) in Dakar, Senegal, responsible for the provision of long-term in situ biomass data from Senegal  ... 
doi:10.3390/rs11050576 fatcat:epw3ei4m45hcbjvnuvipmejzpa

Uncovering Dryland Woody Dynamics Using Optical, Microwave, and Field Data—Prolonged Above-Average Rainfall Paradoxically Contributes to Woody Plant Die-Off in the Western Sahel

Paulo N. Bernardino, Martin Brandt, Wanda De Keersmaecker, Stéphanie Horion, Rasmus Fensholt, Ilié Storms, Jean-Pierre Wigneron, Jan Verbesselt, Ben Somers
2020 Remote Sensing  
This study provides new evidence supporting a better understanding of the "greening Sahel", suggesting that a sudden increase in woody vegetation biomass does not necessarily imply a stable ecosystem recovery  ...  We used a phenology-based remote sensing approach coupled with field data to estimate the severity and recovery rates of a large scale die-off event that occurred in 2014–2015 in Senegal.  ...  Acknowledgments: The authors would like to thank M. Mbaye and everyone else who supported the field data collection.  ... 
doi:10.3390/rs12142332 fatcat:4upntp2hrzflbjk2gerbcwki7y

Remote sensing of vegetation in the Sudano-Sahelian zone: A literature review from 1975 to 2014

Martin Karlson, Madelene Ostwald
2016 Journal of Arid Environments  
The aim of this paper was to investigate how the hands-on application of RS for vegetation analysis has developed in the SSZ by reviewing the scientific literature published between 1975 and 2014.  ...  changes in vegetation productivity and broad vegetation types, whereas its use for studying interactions between vegetation and environmental factors has been relatively low.  ...  Acknowledgements The work has been funded by the Swedish International Development Cooperation Agency (Sida), the Swedish Energy Agency and the Swedish Research Council (VR/Sida).  ... 
doi:10.1016/j.jaridenv.2015.08.022 fatcat:fvoj6zzmmnehjb6lsxmuzmeuga

Evaluation of the Standardized Precipitation Index as an early predictor of seasonal vegetation production anomalies in the Sahel

Michele Meroni, Felix Rembold, Dominique Fasbender, Anton Vrieling
2016 Remote Sensing Letters  
We analysed the performance and timeliness of the Standardized Precipitation Index (SPI) in anticipating deviations from mean seasonal vegetation productivity in the Sahel.  ...  season (zCFAPAR) is used as a proxy of seasonal productivity.  ...  Data and case study description We investigated the link between RFE-derived SPI and FAPAR-derived anomalies of seasonal productivity for the period 1999-2013 in the Sahel.  ... 
doi:10.1080/2150704x.2016.1264020 fatcat:jwldzc7sg5aqxm5piq4ftx4vru

Driving forces of recent vegetation changes in the Sahel: Lessons learned from regional and local level analyses

Louise Leroux, Agnès Bégué, Danny Lo Seen, Audrey Jolivot, Francois Kayitakire
2017 Remote Sensing of Environment  
In this study we proposed to make a bridge 18 between vegetation trend analysis and LULCC studies to improve the understanding of the various 19 factors that influence the biomass production changes observed  ...  in satellite time series (using 20 integrated Normalized Difference Vegetation Index [NDVI] as a proxy).  ...  inter-annual rainfall variability in semi-arid 344 environments, the trends in iNDVI contain a significant rainfall signal.  ... 
doi:10.1016/j.rse.2017.01.014 fatcat:fcgejwalcvexvkuqhl6dnca74m

Do Agrometeorological Data Improve Optical Satellite-Based Estimations of the Herbaceous Yield in Sahelian Semi-Arid Ecosystems?

Abdoul Diouf, Pierre Hiernaux, Martin Brandt, Gayane Faye, Bakary Djaby, Mouhamadou Diop, Jacques Ndione, Bernard Tychon
2016 Remote Sensing  
Acknowledgments: This research was supported by the AGRICAB project (Contract No. 282621), funded by the  ...  After analyzing the SOS metrics against a proxy of biomass production in the Sahel however, [14] indicated that vegetation monitoring and biomass production forecasts should not be based on SOS in areas  ...  So far as we know however, no study has yet investigated the relationship between the onset/end metrics derived from satellite vegetation indices and from rainfall estimates in the West African Sahel.  ... 
doi:10.3390/rs8080668 fatcat:2ekm4vtmofesbefexaqenwamzq

Identifying environmental controls on vegetation greenness phenology through model-data integration

M. Forkel, N. Carvalhais, S. Schaphoff, W. v. Bloh, M. Migliavacca, M. Thurner, K. Thonicke
2014 Biogeosciences Discussions  
We demonstrated that LPJmL with new phenology and optimized parameters better reproduces seasonality, inter-annual variability and trends of vegetation greenness.  ...  Here we implemented a~new phenology model within the LPJmL (Lund Potsdam Jena managed lands) DGVM and integrated several observational data sets to improve the ability of the model in reproducing satellite-derived  ...  We thank Ranga Myneni and Frédéric Baret for their comments on FAPAR datasets. We thank the IT  ... 
doi:10.5194/bgd-11-10917-2014 fatcat:jkgvumbxqzfojdaepkbog47vpa

Identifying environmental controls on vegetation greenness phenology through model–data integration

M. Forkel, N. Carvalhais, S. Schaphoff, W. v. Bloh, M. Migliavacca, M. Thurner, K. Thonicke
2014 Biogeosciences  
We demonstrated that LPJmL with new phenology and optimized parameters better reproduces seasonality, inter-annual variability and trends of vegetation greenness.  ...  Here we implemented a new phenology model within the LPJmL (Lund Potsdam Jena managed lands) DGVM and integrated several observational data sets to improve the ability of the model in reproducing satellite-derived  ...  We thank Ranga Myneni and Frédéric Baret for their comments on FAPAR datasets. We thank the IT  ... 
doi:10.5194/bg-11-7025-2014 fatcat:obndyj3xlfdmberfedfrk2wode

Thirty-two Years of Sahelian Zone Growing Season Non-Stationary NDVI3g Patterns and Trends

Assaf Anyamba, Jennifer Small, Compton Tucker, Edwin Pak
2014 Remote Sensing  
We update the Global Inventory Modeling and Mapping Studies (GIMMS  ...  All authors contributed equally to writing and editing the paper. Conflicts of Interest The authors declare no conflict of interest. Remote Sens. 2014, 6  ...  Acknowledgments This work was made possible by funding from USDA Foreign Agricultural Service Global Agricultural Monitoring project through its support of our operational GIMMS NOAA AVHRR NDVI production  ... 
doi:10.3390/rs6043101 fatcat:5jzy5pv5krd7xdahqdhbejbsum

Topographic Effects on Vegetation Biomass in Semiarid Mixed Grassland under Climate Change Using AVHRR NDVI Data

Zhaoqin Li
2014 British Journal of Environment and Climate Change  
To achieve the objective, the applicability of AVHRR NDVI data being a proxy of vegetation biomass was investigated.  ...  This paper aims to investigate the topographic effects on vegetation biomass under climate change in semiarid Canadian mixed grass prairie.  ...  ACKNOWLEDGEMENTS This research was funded by the ISTP Canada-China project on "Climate Affects Grasslands in Canadian Prairie and Tibet, China". We thank Parks Canada for providing AVHRR/NDVI imagery.  ... 
doi:10.9734/bjecc/2014/11146 fatcat:2uk3cr4mgjcx3fxxny2wuscumi

Global Analysis of Bioclimatic Controls on Ecosystem Productivity Using Satellite Observations of Solar-Induced Chlorophyll Fluorescence

Nima Madani, John Kimball, Lucas Jones, Nicholas Parazoo, Kaiyu Guan
2017 Remote Sensing  
Here, we use a relatively long-term global SIF observational record from the Global Ozone Monitoring Experiment-2 (GOME-2) sensors to investigate the relationships between SIF, used as a proxy for GPP,  ...  We found that productivity in arid ecosystems is more strongly controlled by soil water content to an extent that soil moisture explains a higher proportion of the seasonal cycle in productivity than VPD  ...  The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.  ... 
doi:10.3390/rs9060530 fatcat:dsuniktsxnbsni5ybawzfzodzy

Using Low Resolution Satellite Imagery for Yield Prediction and Yield Anomaly Detection

Felix Rembold, Clement Atzberger, Igor Savin, Oscar Rojas
2013 Remote Sensing  
Low resolution satellite imagery has been extensively used for crop monitoring and yield forecasting for over 30 years and plays an important role in a growing number of operational systems.  ...  Vegetation performance anomaly detection with low resolution images continues to be a fundamental component of early warning and drought monitoring systems at the regional scale.  ...  variability leads to high inter-annual fluctuations in primary production and to a large risk of famines [3] .  ... 
doi:10.3390/rs5041704 fatcat:oq23wwe56vbzfeobfaaadfw2jq
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