Hello,
I am using a VG model that simulates the West central Florida sand, I put alpha=0.03 for having a 30cm AEP, n=1.7, l=0.5, but from profile information it only got 2cm AEP, I changed alpha to 0.025 and 0.3 the AEP still remain 2cm, if change n=3 it has 4cm AEP, but I cannot use very high number for n because that would be unrealistic. How can I change the parameter? Thank you in advance!
alpha equals to inverse of AEP?
alpha equals to inverse of AEP?
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Re: alpha equals to inverse of AEP?
I assume that AEP refers to the AirEntry Point, right? The standard van Genuchten (VG) model does not have an airentry point. In the VG model, the water content increases all the way till the pressure head reaches a zero value. Hydrus offers you an option to use the VG model with the airentry value of – 2 cm (based on some work Rien did and published with Marcell Schaap in early 2000). If you want to have a larger airentry value, you need to use the modified VG model. Then by manipulating the Theta_m value, you can get different values of AEP. J.
Re: alpha equals to inverse of AEP?
Thank you Jirka for explaining,
I meant capillary zone for AEP, I was hoping to have 15cm capillary zone, from the parameters I have it only shows of a 2cm capillary zone, if I want a 15cm capillary zone model I will need to set an unrealistic high n value, how I can change it? And the other question is how can set rootzone thickness? Thank you.
I meant capillary zone for AEP, I was hoping to have 15cm capillary zone, from the parameters I have it only shows of a 2cm capillary zone, if I want a 15cm capillary zone model I will need to set an unrealistic high n value, how I can change it? And the other question is how can set rootzone thickness? Thank you.