Soil Bunds in Aquacrop

Hello Tom,

Just curious as to know what form of soil bunds is Aquacrop considering - is it the contour soil bunds or is the row soil bunds ( like in paddy fields).

So, as per my understanding, the model considers the height of soil bunds in determining the surface runoff; so, will the form of soil bunds have any impact on the surface runoff calculation?

Thank you,

Hi @amoolyaudaishetty

Apologies for the late response, completely forgot about this one. This is a quote from the AC reference manual 3:

Since field management and crop type might affect surface runoff, the user can adjust CNsoil
when specifying the effect of field surface practices affecting surface runoff. The specified
CNsoil, can be adjusted by considering the crop type (if different from ‘small grain’),
treatment and hydrologic conditions. Further-on specific field practices such as tied ridges
and soil bunds might prevent soil surface runoff. In that case the runoff subroutine is
bypassed. When the field is surrounded by soil bunds, water that cannot infiltrate as a result
of excessive rainfall or irrigation will be stored between the bunds. The storage capacity is
however limited by the height of the bunds. Water that overtops the bunds is assumed to
be lost by surface runoff.

So i believe the model is assuming contour soil bunds. I would assume the type of bunds will have an impact on runoff calculations however i am certainly no expert in that area so I would not be able to give you any more info im afraid.


No worries at all @tom.

Right, from the above quote that you’ve shared, I too believe that they are referring to the contour soil bunds - especially if we were to go by the statement "field is surrounded by soil bunds’. But, you see, the passage also mentions “water being stored between the bunds” ( as in between row soil bunds?). This is slightly confusing.

But yeah, I suppose for now I’ll just go with the contour soil bunds.

Thanks for sharing the information and your thought on this, Tom. Appreciate it.