Movement of concentration

A discussion forum for old Hydrus-2D & Meshgen. Happy Posting!
Download PDF document with all topics (February 8, 2008, 1.9MB):
http://www.pc-progress.com//Downloads/F ... on_H2D.pdf
Post Reply
sanjay9376
Posts: 10
Joined: Thu Aug 13, 2009 10:34 am
Location: India

Movement of concentration

Post by sanjay9376 » Wed Mar 23, 2011 1:40 pm

Hello everyone,
I am simulating phosphorus movement under drip fertigation. I am applying the specific quantity of fertilizer. I did the chemical analysis of soil samples at different depths, i found that Phosphorus is moving upto 6o cm even beyond that depth. I am giving all the soil hydraulic properties as per available data or soil catalogue data. But after simulation, the model could not able to show the movement of Phosphorus concentration beyond 10 cm. What might be the reason?
Thanking you in advance

Sanjay

Jirka
Posts: 4620
Joined: Sat Mar 16, 2002 3:47 pm
Location: USA
Location: Riverside, CA

Post by Jirka » Sat Mar 26, 2011 7:52 pm

There are multiple mechanisms that may be responsible for moving phosphorus below the depth predicted by modeling.

One obvious mechanism can be preferential flow. HYDRUS offers you several models that can be used for that, with the simplest being the mobile-immobile water (dual-porosity) model.

Another mechanism can be the colloid-facilitated transport of phosphorus. Here, phosphorus may sorb to colloids, and then colloids may transport phosphorus to deeper depths that could be predicted using uniform transport model. We have this option so far only in the HYDRUS-1D code. You can download this module from the library of HYDRUS-1D projects.

Jirka

Post Reply