Extracting soil water holding capacity parameters of a distributed agro-hydrological model from high resolution optical satellite observations series
2016
Ferrant, Sylvain | Bustillo, Vincent | Burel, Enguerrand | Salmon-Monviola, Jordy | Claverie, Martin | Jarosz, Nathalie | Yin, Tiangang | Rivalland, Vincent | Dedieu, Gérard | Demarez, Valérie | Ceschia, Eric | Probst, Anne | Ahmad, Al Bitar | Kerr, Yann H. | Probst, Jean-Luc | Durand, Patrick | Gascoin, Simon | Centre d'études spatiales de la biosphère (CESBIO) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT) | Institut Universitaire de Technologie - Paul Sabatier (IUT Paul Sabatier) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Sol Agro et hydrosystème Spatialisation (SAS) ; Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST | Department of Geographical Sciences ; University of Maryland [College Park] (UMD) ; University System of Maryland-University System of Maryland | NASA Goddard Space Flight Center (GSFC) | Site Auch ; Institut Universitaire de Technologie - Paul Sabatier (IUT Paul Sabatier) ; Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Centre National de la Recherche Scientifique (CNRS) | École nationale supérieure agronomique de Toulouse (ENSAT) ; Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT)-Université de Toulouse (UT) | Laboratoire Ecologie Fonctionnelle et Environnement (LEFE) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP) ; Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) ; Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT) | Institut National Polytechnique (Toulouse) (Toulouse INP) ; Université de Toulouse (UT) | European Spatial Agency (ESA); research program BAG'AGES - Agence de l'Eau Adour-Garonne (AEAG); CNRS-INSU Observatoire Spatial Regional (OSR) funds; ANR ESCAPADE; ANR RUEdesSOLS; CNES (the French Space Agency); ESA | Mutlu Ozdogan | ANR-14-CE01-0011,RUEdesSOLS,Estimation de la Réserve Utile en Eau des sols par mesures directes et inversion de modèles de cultures, à l'échelle de la parcelle agricole et du territoire(2014)
Sentinel-2 (S2) earth observation satellite mission, launched in 2015, is foreseen to promote within-field decisions in Precision Agriculture (PA) for both: (1) optimizing crop production; and (2) regulating environmental impacts. In this second scope, a set of Leaf Area Index (LAI) derived from S2 type time-series (2006-2010, using Formosat-2 satellite) is used to spatially constrain the within-field crop growth and the related nitrogen contamination of surface water simulated at a small experimental catchment scale with the distributed agro-hydrological model Topography Nitrogen Transfer and Transformation (TNT2). The Soil Water Holding Capacity (SWHC), represented by two parameters, soil depth and retention porosity, is used to fit the yearly maximum of LAI (LAX) at each pixel of the satellite image. Possible combinations of soil parameters, defining 154 realistic SWHC found on the study site are used to force spatially homogeneous SWHC. LAX simulated at the pixel level for the 154 SWHC, for each of the five years of the study period, are recorded and hereafter referred to as synthetic LAX. Optimal SWHCyear_I,pixel_j, corresponding to minimal difference between observed and synthetic LAX(year_I,pixel_j), is selected for each pixel, independent of the value at neighboring pixels. Each re-estimated soil maps are used to re-simulate LAX(year_I). Results show that simulated and synthetic LAX(year_I,allpixels) obtained from SWHCyear_I,allpixels are close and accurately fit the observed LAX(year_I,allpixels) (RMSE = 0.05 m(2)/m(2) to 0.2 and R-2 = 0.99 to 0.94), except for the year 2008 (RMSE = 0.8 m(2)/m(2) and R-2 = 0.8). These results show that optimal SWHC can be derived from remote sensing series for one year. Unique SWHC solutions for each pixel that limit the LAX error for the five years to less than 0.2 m(2)/m(2) are found for only 10% of the pixels. Selection of unique soil parameters using multi-year LAX and neighborhood solution is expected to deliver more robust soil parameters solutions and need to be assessed further. The use of optical remote sensing series is then a promising calibration step to represent crop growth within crop field at catchment level. Nevertheless, this study discusses the model and data improvements that are needed to get realistic spatial representation of agro-hydrological processes simulated within catchments.
显示更多 [+] 显示较少 [-]