GRASS GIS manual: i.biomass

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 lightuseefficiency=name latitude=name dayofyear=name transmissivitysingleway=name wateravailability=name output=name [--overwrite] [--verbose] [--quiet]

Flags:

--overwrite: Allow output files to overwrite existing files
--verbose: Verbose module output
--quiet: Quiet module output

Parameters:

fpar=name [required]: Name of fPAR raster map
lightuseefficiency=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]
transmissivitysingleway=name [required]: Name of single-way transmissivity raster map [0.0-1.0]
wateravailability=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 i.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

It 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.

[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.

AUTHORS

Yann Chemin, Bec de Mortagne, France

Last changed: $Date: 2011-11-08 13:24:20 -0800 (Tue, 08 Nov 2011) $

Main index - Imagery index - Full index