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Plant Available Water Content Units?

yshennanyshennan Member
edited June 2014 in Terrestrial Models

I am running the Nutrient Retention: Water Purification model, and I'm wondering what unit is required for the Plant Available Water Content grid? The user guide says 'a fraction' but doesn't specify anything else... does that mean a %?

I currently have a TIFF file with values in mm from 0-6998. Is this correct?

Thank you!



  • PerrinePerrine Moderator, NatCap Staff
    Dear Yara,

    Apologies that this is not clear in the user guide. PAWC is actually an input to the Water Yield model (which is used in the nutrient model), and the parameter description has not been updated in the nutrient model section. In the meantime, you can check the Water yield user guide: you'll see that PAWC needs to be expressed as a proportion between 0 and 1.

    Additional information can be found in the Data sources section.

    Very likely, your values between 0 and ~7000 are in mm, over the whole soil layer. In that case, you'd divide the value by the soil depth to have the proportion of available water to plants (per unit of soil depth).

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