1. General Model Information
Name: SBFLEVO - Growth model to simulate crop growth, optical reflectance and radar backscatter of sugar beet.
Main medium: terrestrial
Main subject: agriculture, hydrology
Organization level: ecosystem, population
Type of model: ordinary differential equations
Keywords: crop growth, sugar beet, remote sensing, photosynthesis, light interception, light reflection, radar backscatter, optical reflectance
Dr.ir. B.A.M. Bouman.
Research Institute for Agrobiology and Soil Fertility (AB-DLO), Dept. Agrosystems Research, P.O.Box 14, 6700 AA Wageningen, THE NETHERLANDS.
The model simulates daily growth of a sugar beet crop on the basis of underlying physiological and physical processes (e.g. light interception, photosynthesis, respiration), and its optical reflectance and radar backscatter on the basis of physical interaction processes. The crop model part is SUCROS*87 for potential crop growth (i.e. ample supply of water and nutrients, no pests, weeds and diseases). The rate of dry matter accumulation is a function of irradiation, temperature and crop characteristics. The optimal reflectance model is EXTRAD: optical reflectance is simulated in the green, red and infrared bands from soil and crop optical properties, leaf area index, canopy architecture and illumination conditions. The vegetation indices NDVI, WDVI and IR/R-ratio are calculated. The radar backscatter model is CLOUD: radar backscatter (gamma) is simulated from the amount of water in the soil and in the canopy and from soil and canopy backscatter characteristics for several angles of incidence, VV and HH polarization and in Ku1, Ku2, X, C, S and L-bands. All submodels have been parameterized and validated on data collected during several remote sensing campaigns in (South-)Flevoland, The Netherlands, between 1980-1988 (ground based ROVE, Agriscatt).
Purpose of the model:
Model parentage: SUCROS87 and EXTRAD.
Source of the Abstract: CAMASE Register of Agro-ecosystems Models
II. Technical Information
Operating System(s): VAX computer, IBM compatible PC/AT >= 640 Kb RAM.
Costs: : Dfl. 270,=.
Programming Language(s): Microsoft FORTRAN-77.
III. Mathematical Information
Rate variables: Phenological development, leaf and canopy photosynthesis (gross, net), maintenance ad growth respiration, crop growth, growth of plant organs.
State variables: Biomass (total, and per crop organ e.g. leaf, stem, root, tuber), leaf area index, soil cover, intercepted light. Auxiliary variables: reflected solar radiation, vegetation indices, radar backscatter.
Geographical latitude and longitude, weather data (daily radiation, minimum and maximum temperature), top soil moisture content, crop specific physiological and morphological properties, canopy reflection characteristics, canopy and soil radar backscatter backscatter characteristics, crop management information. Input check in model: No.
Crop rate and state variables (e.g. leaf area index, soil cover, biomass), optical canopy reflection, vegetation indices (NDVI, WDVI, IR/Gr ratio), radar backscatter (multi-incidence angle, VV and HH polarization, multi-frequency).
Basic spatial unit: Field level (some m2).
Time interval of simulation: 1 day.
Bouman, B.A.M., 1992. Linking physical remote sensing models with crop growth simulation models, applied to sugar beet. International Journal of Remote Sensing vol 13 no. 14: 2565-2581
Clevers, J.G.P.W., C. Buker, H.J.C. van Leeuwen & B.A.M. Bouman, 1994. A framework for Monitoring crop growth by combining directional and spectral remote sensing information. Accepted for publication in Remote Sensing of Environment 1994.
Bouman, B.A.M., 1992. SBFLEVO and WWFLEVO, Growth models to simulate crop growth, optical reflectance and radar backscatter of sugar beet and winter wheat, calibrated for Flevoland. CABO-DLO report 163. CABO-DLO Wageningen, The Netherlands. 116 pp.
V. Further information in the World-Wide-Web
7. Appendix: PIK Available Model Toolbox 1996
VI. Additional remarks
Parentage: SUCROS87 and EXTRAD.
Last review of this document by: T. Gabele: Dec 10 1997
Status of the document:
last modified by
Joachim Benz Mon Jul 2 18:31:37 CEST 2007