You are just awesome... I love all your soil lectures.
@stellakountoupi53144 жыл бұрын
Excellent, thank you so much!!!
@asrajo5728 Жыл бұрын
you help me understand this confusing thing, Thanks for sharing sir!
@RileyLeff6 ай бұрын
thanks dude
@JieGuo-me5wt4 ай бұрын
As one of the comments mentioned below, l is missing in the relative hydraulic conductivity equation I think.
@villaautomation4 жыл бұрын
could you send me the simulation control with simulink-matlab of the richards equation?
@rotemzilberman2035 Жыл бұрын
Thank you
@PranujAmatya Жыл бұрын
Hi! Good information here. But aren't you missing the lambda exponent on the relative saturation term in the hydraulic conductivity function? I have literature that shows a lambda exponent on there, but its missing here, so just confused. Thanks in advance.
@JieGuo-me5wt4 ай бұрын
i think l (nomally 0.5) is missing there?
@nurlatifahmohdnor8939 Жыл бұрын
In what year U.S. net farm income swelled to $33.3 billion?
@nasrintaghavi68773 жыл бұрын
Hello. Thanks for the excellent video. I have a question about finding Hp of a soil from the curve. Could you please help me with this: I have a soil with theta_s=0.32, theta_r=0.01, the soil field moisture content is 35.2%. I have the retention curve, but I don't know how to extract its related Hp from the curve. Do I need to use the field moisture content as theta in the bottom axis to find the Hp on the vertical axis? If yes, field moisture content=35.2% is more than theta_s=0.32. Is this possible?
@selkerjss3 жыл бұрын
Please note that in this formulation, theta-s is the maximum water content of a soil. So your proposed situation is not possible.
@nasrintaghavi68773 жыл бұрын
@@selkerjss Yes, thank you so much for clarification, that's exactly why I asked it. I actually got these data from a lab, there is a column of data called "saturation" which I think it's the saturated system to start pulling the water out. I've asked them to clarify it, and if it's the case, then theta_s would be more than field moisture content that seems to be right. Just another quick question: Is the field moisture content (%) at 105 degree, the gravimetric moisture content? If yes, I will need to convert it to volumetric moisture content, put this on the curve and get the related pressure (h), right? Thanks again!
@selkerjss3 жыл бұрын
@@nasrintaghavi6877 Hello Nasrin - when you see data associated with 105 degrees, this is typically indicating the "oven dry" condition. It can be expressed either gravimetrically or volumetrically, which in either case can be put in % terms. So I cannot give you a solid answer. You need to look at the laboratory procedures.
@nasrintaghavi68773 жыл бұрын
@@selkerjss Dear John, thanks for your help! It is not mentioned in the laboratory files, so I just asked them to clarify it. Cheers.
@ZXD13145 ай бұрын
Please can you share soil hydrology and biophysics
@Vindikatorz Жыл бұрын
what is the reference for this?
@selkerjss Жыл бұрын
van Genuchten, M.Th. (1980). "A closed-form equation for predicting the hydraulic conductivity of unsaturated soils". Soil Science Society of America Journal. 44 (5): 892-898. Bibcode:1980SSASJ..44..892V. doi:10.2136/sssaj1980.03615995004400050002x. hdl:10338.dmlcz/141699.
@jaimejacobc4 жыл бұрын
How we can measure the values of pressure and saturation of a soil in different deep. I would like to write to your email.
@selkerjss4 жыл бұрын
Look up the "instantaneous profile method." Typically you use a TDR/dielectric sensor or neutron probe for moisture, and a tensiometer for pressure. You dig a hole, and install them into the sides of the hole and re-fill the hole. That said, there are many approaches - it really depends on your site and objectives.
@jaimejacobc4 жыл бұрын
@@selkerjss I understood John. My focus of my question is this. I´m a Metallurgical Engineering, and I need to model the movement of solution in a unsaturated porous media (heap leaching), but the studies that I have been read they modelling the head of suction vs saturation or moisture of ore using the Van Genuchten model. But how they measurement both parameters (head of suction and saturation) to adjust the permeability? Can you ligth me in that please. Greetings Jaime
@techlegend3363 Жыл бұрын
Hello, any one can help me by giving Modflow and Hydrus software for Macbook, thanks Well Explain You great concepts are clear now