## 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

Last changed: $Date$