TY - JOUR
T1 - Modification of DAISY SVAT model for potential use of remotely sensed data
AU - van der Keur, Peter
AU - Hansen, Søren
AU - Schelde, Kirsten
AU - Thomsen, Anton
N1 - Funding Information:
The RS-Model research program within the framework of the Earth Observation Program is funded by the Danish Space Board Committee, the Danish Agricultural and Veterinary Research Council and the Danish Technical Research Council. Per Abrahamsen (Danish Informatics Network in the Agricultural Sciences) is greatly acknowledged for his help on DAISY programming and technical advice.
PY - 2001/2/3
Y1 - 2001/2/3
N2 - The SVAT model DAISY is modified to be able to utilize remote sensing (RS) data in order to improve prediction of evapotranspiration and photosynthesis at plot scale. The link between RS data and the DAISY model is the development of the minimum, unstressed, canopy resistance rminc during the growing season. Energy balance processes are simulated by applying resistance networks and a two-source model. Modeled data is validated against measurements performed for a winter wheat plot. Soil water content is measured by time domain reflectometry. Crop dry matter content and leaf area index are modeled adequately. Modeled soil water content, based on a Brooks and Corey [Brooks, R.H., Corey, A.T., 1964. Hydraulic properties of porous media. Hydrology Paper no. 3, Colorado University, Fort Collins, CO, 27 pp.] parameterization, from 0 to 20, 0 to 50 and 0 to 100 cm is calibrated satisfactorily against measured TDR values. Simulated and observed energy fluxes are generally in good agreement when water supply in the root zone is not limiting. With decreasing soil moisture content during a longer drought period, modeled latent heat flux is lower than observed, which calls for both improved parameterizations for environmental controls and for a improved estimation of the rminc parameter.
AB - The SVAT model DAISY is modified to be able to utilize remote sensing (RS) data in order to improve prediction of evapotranspiration and photosynthesis at plot scale. The link between RS data and the DAISY model is the development of the minimum, unstressed, canopy resistance rminc during the growing season. Energy balance processes are simulated by applying resistance networks and a two-source model. Modeled data is validated against measurements performed for a winter wheat plot. Soil water content is measured by time domain reflectometry. Crop dry matter content and leaf area index are modeled adequately. Modeled soil water content, based on a Brooks and Corey [Brooks, R.H., Corey, A.T., 1964. Hydraulic properties of porous media. Hydrology Paper no. 3, Colorado University, Fort Collins, CO, 27 pp.] parameterization, from 0 to 20, 0 to 50 and 0 to 100 cm is calibrated satisfactorily against measured TDR values. Simulated and observed energy fluxes are generally in good agreement when water supply in the root zone is not limiting. With decreasing soil moisture content during a longer drought period, modeled latent heat flux is lower than observed, which calls for both improved parameterizations for environmental controls and for a improved estimation of the rminc parameter.
KW - Crop energy balance
KW - DAISY model
KW - Minimum canopy resistance
KW - Remote sensing
UR - http://www.scopus.com/inward/record.url?scp=0035798905&partnerID=8YFLogxK
U2 - 10.1016/S0168-1923(00)00212-4
DO - 10.1016/S0168-1923(00)00212-4
M3 - Article
AN - SCOPUS:0035798905
SN - 0168-1923
VL - 106
SP - 215
EP - 231
JO - Agricultural and Forest Meteorology
JF - Agricultural and Forest Meteorology
IS - 3
ER -