Skip to content

i.biomass

Computes biomass growth, precursor of crop yield calculation.

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

Example:

i.biomass fpar=name lightuse_efficiency=name latitude=name dayofyear=name transmissivity_singleway=name water_availability=name output=name

grass.script.run_command("i.biomass", fpar, lightuse_efficiency, latitude, dayofyear, transmissivity_singleway, water_availability, output, overwrite=None, verbose=None, quiet=None, superquiet=None)

Example:

gs.run_command("i.biomass", fpar="name", lightuse_efficiency="name", latitude="name", dayofyear="name", transmissivity_singleway="name", water_availability="name", output="name")

grass.tools.Tools.i_biomass(fpar, lightuse_efficiency, latitude, dayofyear, transmissivity_singleway, water_availability, output, overwrite=None, verbose=None, quiet=None, superquiet=None)

Example:

tools = Tools()
tools.i_biomass(fpar="name", lightuse_efficiency="name", latitude="name", dayofyear="name", transmissivity_singleway="name", water_availability="name", output="name")

This grass.tools API is experimental in version 8.5 and expected to be stable in version 8.6.

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]
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

fpar : str, required
    Name of fPAR raster map
    Used as: input, raster, name
lightuse_efficiency : str, required
    Name of light use efficiency raster map (UZB:cotton=1.9)
    Used as: input, raster, name
latitude : str, required
    Name of degree latitude raster map [dd.ddd]
    Used as: input, raster, name
dayofyear : str, required
    Name of Day of Year raster map [1-366]
    Used as: input, raster, name
transmissivity_singleway : str, required
    Name of single-way transmissivity raster map [0.0-1.0]
    Used as: input, raster, name
water_availability : str, required
    Value of water availability raster map [0.0-1.0]
    Used as: input, raster, name
output : str, required
    Name for output daily biomass growth raster map [kg/ha/d]
    Used as: output, raster, name
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: None
verbose: bool, optional
    Verbose module output
    Default: None
quiet: bool, optional
    Quiet module output
    Default: None
superquiet: bool, optional
    Very quiet module output
    Default: None

fpar : str, required
    Name of fPAR raster map
    Used as: input, raster, name
lightuse_efficiency : str, required
    Name of light use efficiency raster map (UZB:cotton=1.9)
    Used as: input, raster, name
latitude : str, required
    Name of degree latitude raster map [dd.ddd]
    Used as: input, raster, name
dayofyear : str, required
    Name of Day of Year raster map [1-366]
    Used as: input, raster, name
transmissivity_singleway : str, required
    Name of single-way transmissivity raster map [0.0-1.0]
    Used as: input, raster, name
water_availability : str, required
    Value of water availability raster map [0.0-1.0]
    Used as: input, raster, name
output : str, required
    Name for output daily biomass growth raster map [kg/ha/d]
    Used as: output, raster, name
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: None
verbose: bool, optional
    Verbose module output
    Default: None
quiet: bool, optional
    Quiet module output
    Default: None
superquiet: bool, optional
    Very quiet module output
    Default: None

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.

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.

SEE ALSO

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

AUTHOR

Yann Chemin, Bec de Mortagne, France

SOURCE CODE

Available at: i.biomass source code (history)
Latest change: Friday Aug 08 09:39:19 2025 in commit ed72c71