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2020
Statistical,
data-driven methods are considered good alternatives to process-based models
for the sub-national monitoring of cereal crop yields, since they can flexibly
handle large datasets and can be calibrated simultaneously to different areas.
Here, we assess the influence of several characteristics on the ability of
these methods to forecast cereal yields at the local scale. We look at two
diverse agro-climatic …
Agriculture
provides humanity with food, fibers, fuel, and raw materials that are paramount
for human livelihood. Today, this role must be satisfied within a context of
environmental sustainability and climate change, combined with an unprecedented
and still-expanding human population size, while maintaining the viability of
agricultural activities to ensure both subsistence and livelihoods. Remote
sensing has the capacity to assist the …
A physically based metamodel is proposed to describe the dependency of canopy reflectance on the wavelength, leaf and soil optical properties. The four-stream solution is first applied to describe the interaction between the soil background and the vegetation layers. This leads to the calibration of four terms for a given canopy structure, observation configuration and …
Selection of sugar beet (Beta vulgaris L.) cultivars that are resistant to Cercospora Leaf Spot (CLS) disease is critical to increase yield. Such selection requires an automatic, fast, and objective method to assess CLS severity on thousands of cultivars in the field. For this purpose, we compare the use of submillimeter scale RGB imagery acquired …
Accurate and timely observations of wheat phenology and, particularly, of heading date are instrumental for many scientific and technical domains such as wheat ecophysiology, crop breeding, crop management or precision agriculture. Visual annotation of the heading date in situ is a labour-intensive task that may become prohibitive in scientific and technical activities where high-throughput is needed. This …
The detection of wheat heads in plant images is an important task for estimating pertinent wheat traits including head population density and head characteristics such as health, size, maturity stage, and the presence of awns. Several studies have developed methods for wheat head detection from high-resolution RGB imagery based on machine learning algorithms. However, these …
2019
Authors : Beauchêne K, Leroy F, Fournier A, Huet C, Bonnefoy M, Lorgeou J, de Solan B, Piquemal B, Thomas S and Cohan J-P | Abstract :
In order to evaluate the impact of water deficit in field conditions, researchers or breeders must set up large experiment networks in very restrictive field environments. Experience shows that half …
Authors : Xiuliang Jin; Simon Madec; Dan Dutartre; Benoit de Solan; Alexis Comar; Frédéric Baret | Abstract :
Total above-ground biomass at harvest and ear density are two important traits that characterize wheat genotypes. Two experiments were carried out in two different sites where several genotypes were grown under contrasted irrigation and nitrogen treatments. A high …
Authors : Toreti ; Andrea ; A. Belward ; I. Perez‐Dominguez ; G. Naumann ; J. Luterbacher ; O. Cronie ; L. Seguini ; G. Manfron ; R. Lopez-Lozano ; B. Baruth ; M. van den Berg ; F. Dentener ; A. Ceglar ; T. Chatzopoulos ; M. Zampieri | Abstract :
Temperature and precipitation are …
Authors : Meroni, Michelen; Fasbender, Dominique ; Lopez-Lozano, Raul ; Migliavacca, Mirco | Abstract :
The application of detailed process-oriented simulation models for gross primary production (GPP) estimation is constrained by the scarcity of the data needed for their parametrization. In this manuscript, we present the development and test of the assimilation of Moderate Resolution Imaging …
Authors : Yan Guangjian; Hu Ronghai; Luo Jinghui; Marie, Weiss; Jiang Hailan; Mu Xihan; Xie Donghui; Zhang Wuming | Abstract :
Leaf area index (LAI) is a key parameter of vegetation structure in the fields of agriculture, forestry, and ecology. Optical indirect methods based on the Beer-Lambert law are widely adopted in numerous fields given their …
Authors : Garcia-Condado, Sara; Lopez-Lozano, Raul; Panarello, Lorenzo; Cerrani, Iacopo; Nisini, Luigi; Zucchini, Antonio; Van der Velde, Marijn; Baruth, BettinaGarcia-Condado, Sara; Lopez-Lozano, Raul; Panarello, Lorenzo; Cerrani, Iacopo; Nisini, Luigi; Zucchini, Antonio; Van der Velde, Marijn; Baruth, Bettina | Abstract :
This study assesses crop residues in the EU from major crops using empirical models to predict …
Authors : Madec, Simon; Jin, Xiuliang; Lu, Hao; De Solan, Benoit; Liu, Shouyang; Duyme, Florent; Heritier, Emmanuelle; Baret, Frederic | Abstract :
Wheat ear density estimation is an appealing trait for plant breeders. Current manual counting is tedious and inefficient. In this study we investigated the potential of convolutional neural networks (CNNs) to provide accurate ear …
2018
Authors : Bablet, A.; Vu, P. V. H.; Jacquemoud, S.; Viallefont-Robinet, F.; Fabre, S.; Briottet, X.; Sadeghi, M.; Whiting, M. L.; Baret, F.; Tian, J. | Abstract :
Surface soil moisture content (SMC) is known to impact soil reflectance at all wavelengths of the solar spectrum. As a consequence, many semi-empirical methods aim at inferring SMC …
Authors : Delloye, Cindy; Weiss, Marie; Defourny, Pierre | Abstract :
One of the most common approaches to reducing the environmental impact of nitrogen (N) fertilisation in intensive agrosystems is to adjust the N input of the crop requirement. This adjustment is frequently related to the nitrogen nutrition index (NNI) based on the concepts of the …
Authors : Brede, Benjamin; Gastellu-Etchegorry, Jean-Philippe; Lauret, Nicolas; Baret, Frederic; Clevers, Jan G. P. W.; Verbesselt, Jan; Herold, Martin | Abstract :
Land Surface Phenology (LSP) and Leaf Area Index (LAI) are important variables that describe the photosynthetically active phase and capacity of vegetation. Both are derived on the global scale from optical satellite sensors and …
Authors : Olioso, Albert; Jacob, Frederic; Weiss, Marie | Abstract :
The SAIL-Thermique model was developed to simulate land surface emissivity. It is adapted from the original SAIL model. A specific experiment was set-up over a soybean canopy for evaluating spectral emissivity simulations. Multispectral data were obtained thanks to a CIMEL CE 312-2 radiometer and emissivities …
Authors : Roujean, Jean-Louis; Olioso, Albert; Ceschia, Eric; Hagolle, Olivier; Weiss, Marie | Abstract :
Satellite Sentinel-2 offers a global coverage of the Earth at the frequency of a few days with pixel size ranging from 10 to 20 meters. Such spatio-temporal resolution fosters an advanced research in agriculture. Accounting for BRDF (Bidirectional Reflectance Distribution Function) …
Authors : Baret, Frederic; Madec, Simon; Irfan, Kamran; Lopez, Jeremy; Comar, Alexis; Hemmerle, Matthieu; Dutartre, Dan; Praud, Sebastien; Tixier, Marie Helene | Abstract :
Leaf rolling in maize crops is one of the main plant reactions to water stress that can be visually scored in the field. However, leaf-scoring techniques do not meet the high-throughput requirements …
Authors : Liu, Shouyang; Baret, Frederic; Andrieu, Bruno; Abichou, Mariem; Allard, Denis; de Solan, Benoit; Burger, Philippe | Abstract :
This work investigates the spatial distribution of wheat plants and its consequences on the canopy structure. A set of RGB images were taken from nadir on a total 14 plots showing a range of sowing densities, …
Authors : Jiang, Jingyi; Comar, Alexis; Burger, Philippe; Bancal, Pierre; Weiss, Marie; Baret, Frederic | Abstract :
Background: Leaf biochemical composition corresponds to traits related to the plant state and its functioning. This study puts the emphasis on the main leaf absorbers: chlorophyll a and b (C-ab), carotenoids (C-c), water (C-w) and dry mater (C-m) contents. …
Authors : Franch, Belen; Vermote, Eric F.; Roger, Jean-Claude; Murphy, Emilie; Becker-Reshef, Inbal; Justice, Chris; Claverie, Martin; Nagol, Jyoteshwar; Csiszar, Ivan; Meyer, Dave; Baret, Frederic; Masuoka, Edward; Wolfe, Robert; Devadiga, Sadashiva | Abstract :
The Advanced Very High Resolution Radiometer (AVHRR) sensor provides a unique global remote sensing dataset that ranges from the 1980s to the …
2017
Authors : Liu, Shouyang; Baret, Fred; Abichou, Mariem; Boudon, Fred; Thomas, Samuel; Zhao, Kaiguang; Fournier, Christian; Andrieu, Bruno; Irfan, Kamran; Hemmerle, Matthieu; de Solan, Benoit | Abstract :
The use of active remote sensing techniques based on light detection and ranging (LiDAR) was investigated here to estimate the green area index (GAI) of wheat crops. Emphasis …
Authors : Madec, Simon; Baret, Fred; de Solan, Benoit; Thomas, Samuel; Dutartre, Dan; Jezequel, Stephane; Hemmerle, Matthieu; Colombeau, Gallian; Comar, Alexis | Abstract :
The capacity of LiDAR and Unmanned Aerial Vehicles (UAVs) to provide plant height estimates as a high-throughput plant phenotyping trait was explored. An experiment over wheat genotypes conducted under well watered …
Authors : Li, Wenjuan; Baret, Frederic; Weiss, Marie; Buis, Samuel; Lacaze, Roselyne; Demarez, Valerie; Dejoux, Jean-francois; Battude, Marjorie; Camacho, Fernando | Abstract :
A wide range of ecological, agricultural, hydrological and meteorological applications at local to regional scales requires decametric biophysical data. However, before the launch of SENTINEL-2A, only few decametric products are produced and most …
Authors : Yan Guangjian; Hu Ronghai; Luo Jinghui; Marie, Weiss; Jiang Hailan; Mu Xihan; Xie Donghui; Zhang Wuming | Abstract :
Accurate estimation of leaf chlorophyll content (Cab) from remote sensing is of tremendous significance to monitor the physiological status of vegetation or to estimate primary production. Many vegetation indices (Vls) have been developed to retrieve …
Authors : Jacob, Frederic; Lesaignoux, Audrey; Olioso, Albert; Weiss, Marie; Caillault, Karine; Jacquemoud, Stephane; Nerry, Francoise; French, Andrew; Schmugge, Thomas; Briottet, Xavier; Lagouarde, Jean-Pierre | Abstract :
We investigated the use of multispectral thermal imagery to retrieve land surface emissivity and temperature. Conversely to concurrent methods, the temperature emissivity separation (TES) method simply requires single overpass …
Authors : Jin, Xiuliang; Liu, Shouyang; Baret, Frederic; Hemerle, Matthieu; Comar, Alexis | Abstract :
Plant density is useful variable that determines the fate of the wheat crop. The most commonly used method for plant density quantification is based on visual counting from ground level. The objective of this study is to develop and evaluate a …
Authors : Yan Guangjian; Hu Ronghai; Luo Jinghui; Marie, Weiss; Jiang Hailan; Mu Xihan; Xie Donghui; Zhang Wuming | Abstract :
Background: Plant density and its non-uniformity drive the competition among plants as well as with weeds. They need thus to be estimated with small uncertainties accuracy. An optimal sampling method is proposed to estimate the …
Authors : Liu, Shouyang; Baret, Fred; Andrieu, Bruno; Burger, Philippe; Hemmerle, Matthieu | Abstract :
Crop density is a key agronomical trait used to manage wheat crops and estimate yield. Visual counting of plants in the field is currently the most common method used. However, it is tedious and time consuming. The main objective of this …
Authors : Weiss, Marie; Baret, Frederic | Abstract :
In the context of precision viticulture, remote sensing in the optical domain offers a potential way to map crop structure characteristics, such as vegetation cover fraction, row orientation or leaf area index, that are later used in decision support tools. A method based on the RGB color …
2016
Authors : Inoue, Yoshio; Guerif, Martine; Baret, Frederic; Skidmore, Andrew; Gitelson, Anatoly; Schlerf, Martin; Darvishzadeh, Roshanak; Olioso, Albert | Abstract :
Canopy chlorophyll content (CCC) is an essential ecophysiological variable for photosynthetic functioning. Remote sensing of CCC is vital for a wide range of ecological and agricultural applications. The objectives of this study were to explore …
Authors : Baret, Frederic | Abstract :
The supply of biophysical variables derived from satellite observations serves several applications related to agriculture, the environment, resource management and the climate. Moreover, these same variables may be acquired at a range of scales:. -at the very local level, the use of precision agriculture allows adapting cultural practices to …
Authors : Vuolo, Francesco; Zoltak, Mateusz; Pipitone, Claudia; Zappa, Luca; Wenng, Hannah; Immitzer, Markus; Weiss, Marie; Baret, Frederic; Atzberger, Clement | Abstract :
This technical note presents the first Sentinel-2 data service platform for obtaining atmospherically-corrected images and generating the corresponding value-added products for any land surface on Earth. Using the European Space Agency's (ESA) Sen2Cor …
Authors : Verger, Aleixandre; Kandasamy, Sivasathivel; Baret, Frederic | Abstract :
Time series processing is an important ingredient of a biophysical algorithm in order to get the expected continuous and smooth dynamics required by many applications. Several temporal techniques have been proposed to reduce noise and fill gaps in the time series of satellite data. The …
Authors : Steven, Michael D.; Malthus, Timothy J.; Baret, Frederic | Abstract :
No abstract.
Authors : Gouache, David; Beauchene, Katia; Mini, Agathe; Fournier, Antoine; de Solan, Benoit; Baret, Fred; Comar, Alexis | Abstract :
Digital and image analysis technologies in greenhouses have become commonplace in plant science research and started to move into the plant breeding industry. However, the core of plant breeding work takes place in fields. We will …
Authors : Tagliabue, Giulia; Panigada, Cinzia; Colombo, Roberto; Fava, Francesco; Cilia, Chiara; Baret, Frederic; Vreys, Kristin; Meuleman, Koen; Rossini, Micol | Abstract :
The accurate mapping of forest species is a very important task in relation to the increasing need to better understand the role of the forest ecosystem within environmental dynamics. The objective of this …
2015
Authors : Li, Wenjuan; Weiss, Marie; Waldner, Francois; Defourny, Pierre; Demarez, Valerie; Morin, David; Hagolle, Olivier; Baret, Frederic | Abstract :
The leaf area index (LAI) and the fraction of photosynthetically active radiation absorbed by green vegetation (FAPAR) are essential climatic variables in surface process models. FCOVER is also important to separate vegetation and soil for …
2014
Authors : Verger, Aleixandre; Vigneau, Nathalie; Cheron, Corentin; Gilliot, Jean-Marc; Comar, Alexis; Baret, Frederic
| Abstract :
Unmanned airborne systems (UAS) technology opens new horizons in precision agriculture for effective characterization of the variability in crop state at high spatial resolution and high revisit frequency. Green area index (GAI) is a key agronomic variable involved in …
Authors : Fernandes, Richard; Weiss, Marie; Camacho, Fernando; Berthelot, Beatrice; Baret, Fred; Duca, Riccardo | Abstract :
Leaf area index (LAI) is identified as a Level 2b product to be derived from the Sentinel-2 (S2) Multispectral Imager (MSI) in support of user services [1]. The Validation of Sentinel 2 (VALSE2) project conducted a review, implementation and …
Authors : Comar, Alexis; Baret, Frederic; Obein, Goel; Simonot, Lionel; Meneveaux, Daniel; Vienot, Francoise; de Solan, Benoit | Abstract :
Leaf reflectance of monocotyledons generally displays a strong azimuthal anisotropy due to the longitudinal orientation of the veins. The Cook and Torrance (CT) bidirectional reflectance distribution function model was adapted to account for this distinctive feature. …
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