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

NAME  KEYWORDS  SYNOPSIS  Flags:  Parameters:  DESCRIPTION  NOTES  TODO  REFERENCES  SEE ALSO  AUTHOR  SOURCE CODE 

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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.

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: Wednesday Nov 27 22:53:26 2024 in commit: b90ce69e88409469369ec1edb86fde8ec822af8b

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