Crop coefficient

[Alice Bernini]

Hello everyone,

I'm seeking information on which crop coefficient (Kc) QSWAT utilizes and where I can find this information.

Thank you in advance for your assistance.

Alice

[Mourad Guesri]

Hi Alice,

I've only worked with swat on rainfall-runoff modelling but maybe this information can help:

The crop coefficient (Kc) used by QSWAT is typically derived from standard values that are adjusted based on local conditions. These coefficients are crucial for calculating crop evapotranspiration (ETc) and are determined by the product of Kc and the reference evapotranspiration (ETo). The Kc values represent the crop type and its stage of development, which can vary during the crop's growth cycle.

For detailed information on crop coefficients used in SWAT or QSWAT, you can refer to the FAO Irrigation and Drainage Paper No. 56, which provides a comprehensive list of crop coefficients for various growth stages of different crops². Additionally, local agricultural or water management authorities may have adapted these coefficients to local conditions, so it's worth checking with them as well.

If you're looking for specific Kc values for a particular crop or region, you might find the information in scientific publications or databases related to agricultural water management³. Remember, the actual Kc values used in a QSWAT model may be adjusted based on field observations and local climate data to reflect the actual water use of crops more accurately.

Source: Conversation with Bing, 4/8/2024

(1) Chapter 6 - ETc - Single crop coefficient (Kc) - Food and Agriculture .... https://www.fao.org/3/X0490E/x0490e0b.htm.

(2) Actual and standard crop coefficients for semi-natural and planted .... https://link.springer.com/article/10.1007/s00271-023-00867-6.

(3) Crop Coefficients - Farmwest. https://farmwest.com/climate/calculator-information/et/crop-coefficients/.

(4) Determining crop coefficient, yield response factor to water ... - Springer. https://link.springer.com/article/10.1007/s42535-023-00661-x.

Best regards 

Mourad Guesri