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Agro-hydrology and multi-temporal high-resolution remote sensing: toward an explicit spatial processes calibration

Ferrant, Sylvain and Gascoin, Simon and Veloso, Amanda and Salmon-Monviola, Jordy and Claverie, Martin and Rivalland, Vincent and Dedieu, Gérard and Demarez, Valerie and Ceschia, Eric and Probst, Jean-Luc and Durand, Patrick and Bustillo, Vincent Agro-hydrology and multi-temporal high-resolution remote sensing: toward an explicit spatial processes calibration. (2014) Hydrology and Earth System Sciences, 18 (12). 5219-5237. ISSN 1027-5606

(Document in English)

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Official URL: http://dx.doi.org/10.5194/hess-18-5219-2014


The growing availability of high-resolution satellite image series offers new opportunities in agrohydrological research and modeling. We investigated the possibilities offered for improving crop-growth dynamic simulation with the distributed agro-hydrological model: topography-based nitrogen transfer and transformation (TNT2). We used a leaf area index (LAI) map series derived from 105 Formosat-2 (F2) images covering the period 2006–2010. The TNT2 model (Beaujouan et al., 2002), calibrated against discharge and in-stream nitrate fluxes for the period 1985–2001, was tested on the 2005–2010 data set (climate,land use, agricultural practices, and discharge and nitrate fluxes at the outlet). Data fromthe first year (2005) were used to initialize the hydrological model. A priori agricultural practices obtained from an extensive field survey, such as seeding date, crop cultivar, and amount of fertilizer, were used as input variables. Continuous values of LAI as a function of cumulative daily temperature were obtained at the crop-field level by fitting a double logistic equation against discrete satellite-derived LAI. Model predictions of LAI dynamics using the a priori input parameters displayed temporal shifts from those observed LAI profiles that are irregularly distributed in space (between field crops) and time (between years). By resetting the seeding date at the crop-field level,we have developed an optimization method designed to efficiently minimize this temporal shift and better fit the crop growth against both the spatial observations and crop production. This optimization of simulated LAI has a negligible impact on water budgets at the catchment scale (1mmyr 1 on average) but a noticeable impact on in-stream nitrogen fluxes (around 12 %), which is of interest when considering nitrate stream contamination issues and the objectives of TNT2 modeling. This study demonstrates the potential contribution of the forthcoming high spatial and temporal resolution products from the Sentinel-2 satellite mission for improving agro-hydrological modeling by constraining the spatial representation of crop productivity.

Item Type:Article
Additional Information:Thanks to European Geosciences Union editor. The definitive version is available at http://www.hydrology-and-earth-system-sciences.net. The original PDF of the article can be found at Hydrology and Earth System Sciences website : http://www.hydrol-earth-syst-sci.net/18/5219/2014/hess-18-5219-2014.html
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:Other partners > Agrocampus Ouest (FRANCE)
French research institutions > Centre National d'Études Spatiales - CNES (FRANCE)
French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Université de Toulouse > Institut National Polytechnique de Toulouse - Toulouse INP (FRANCE)
French research institutions > Institut National de la Recherche Agronomique - INRA (FRANCE)
French research institutions > Institut de Recherche pour le Développement - IRD (FRANCE)
Other partners > National Aeronautics and Space Administration - NASA (USA)
Université de Toulouse > Université Toulouse III - Paul Sabatier - UT3 (FRANCE)
Other partners > University of Maryland (USA)
Laboratory name:
Sylvain Ferrant was the recipient of a CNES posdocrate research grant
Deposited On:30 Sep 2015 12:37

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