---
name: "i.biomass"
section: "1grass"
platform: "linux"
package: "grass-doc"
version: "8.4.1-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/i.biomass"
---

# i.biomass(1grass)

Computes biomass growth, precursor of crop yield calculation.

## 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)

Accessed: Monday Feb 24 17:51:31 2025

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