NAME

       i.biomass  - Computes biomass growth, precursor of crop yield calculation.

KEYWORDS

       imagery, biomass, FPAR, yield

SYNOPSIS

       i.biomass
       i.biomass --help
       i.biomass  fpar=name  lightuse_efficiency=name latitude=name dayofyear=name transmissivity_singleway=name
       water_availability=name output=name  [--overwrite]  [--help]  [--verbose]  [--quiet]  [--ui]

   Flags:
       --overwrite
           Allow output files to overwrite existing files

       --help
           Print usage summary

       --verbose
           Verbose module output

       --quiet
           Quiet module output

       --ui
           Force launching GUI dialog

   Parameters:
       fpar=name [required]
           Name of fPAR raster map

       lightuse_efficiency=name [required]
           Name of light use efficiency raster map (UZB:cotton=1.9)

       latitude=name [required]
           Name of degree latitude raster map [dd.ddd]

       dayofyear=name [required]
           Name of Day of Year raster map [1-366]

       transmissivity_singleway=name [required]
           Name of single-way transmissivity raster map [0.0-1.0]

       water_availability=name [required]
           Value of water availability raster map [0.0-1.0]

       output=name [required]
           Name for output daily biomass growth raster map [kg/ha/d]

DESCRIPTION

       i.biomass calculates the biomass growth for a day after [1][2].  Input:

           •   fPAR, the modified Photosynthetic Active Radiation for crops.

           •   Light Use Efficiency [0.0-1.0], in Uzbekistan cotton is at 1.9 most of the time.

           •   Latitude [0.0-90.0], from r.latlong.

           •   DOY [1-366].

           •   Transmissivity of the atmosphere single-way [0.0-1.0], mostly around 0.7+ in clear sky.

           •   Water availability [0.0-1.0], possibly using direct output from i.eb.evapfr.

NOTES

       i.biomass can use the output of i.eb.evapfr directly as water availability input.

TODO

       Remove Latitude, DOY and Tsw from input and replace with a raster input compatible with r.sun output.

SEE ALSO

        i.eb.evapfr, r.latlong, r.sun

REFERENCES

       [1] Bastiaanssen, W.G.M., Ali,  S.,  2002.  A  new  crop  yield  forecasting  model  based  on  satellite
       measurements  applied  across  the  Indus  Basin,  Pakistan.  Agriculture,  Ecosystems  and  Environment,
       94(3):321-340. (PDF)

       [2] Chemin, Y., Platonov, A.,  Abdullaev,  I.,  Ul-Hassan,  M.  2005.   Supplementing  farm  level  water
       productivity assessment by remote sensing in transition economies. Water International. 30(4):513-521.

AUTHOR

       Yann Chemin, Bec de Mortagne, France

SOURCE CODE

       Available at: i.biomass source code (history)

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       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual