irrigation+rainfall = evaporation + transpiration + runoff + leaching Which one of these processes do Farmers really have control over during the growing season? If you have the ability to irrigate your sandy soils and water is cheap and plentiful, then you are fortunate and have some control on the left side of the equation. If you do not have irrigation, you must look at the factors on the right side of the equation to see what can be controlled or minimized to benefit your crop. Evaporation from the soil surface can be reduced with mulch or leaving crop residue on the soil surface. Transpiration is a function of the plant leaf surface area and the weather. Runoff is or should be minimal in sandy textured soils with high percolation rates. This leaves the leaching of water out of the root zone as the #1 controllable loss of moisture to your crop. Interrupting the downward movement of moisture in your soil by installing a "smart" barrier can greatly reduce the leaching of water and nutrients. SWRT subsurface membranes detain/retain up to 90% of irrigation or rainfall in the root zone for crop use by disrupting the gravitational movement of water in the soil while still allowing excess water to percolate and do not create anaerobic soil conditions.
According to our agronomists, the reason is that soils are not (except very rarely) made of just one soil type, but a mix of sand, silt, and clay. Soils that are considered “high” in clay might have 30% clay but it is the silt that is causing the capillary rise, as shown in the video.
@@PurdueExtension the pores "shutting" down by swelling is caused by the presence of expansive clay minerals (e.g. montmorilonite or another smectite; structure 2:1). If these minerals are not present (some 1:1 expand a little as well) then you may have a higher rise. Same for silt. Expansive (2:1) clay minerals may affect the capillary rise.
Hello @C Xyooj - As the video discussed, capillary rise is greatest in silty soils (medium to fine particle sizes), and lower in both sandy (coarse particles) and clayey (very fine particles) soils. Capillary rise can be calculated with the capillary rise equation for sands and silts, but it cannot really be calculated for the clays because the flow is so slow in the clays due to the extremely small pores. For sandy and silty soils, the height (h) of water rise is determined by the largest pore sizes in the material. The capillary rise equation is h=(2) (surface tension) / (radius of pores)(density of water)(gravitational acceleration). So for example, for a soil material with largest pore size radius of 0.01 cm, the calculation would be: H=(2)(72.7 g/sec2) / (0.01cm)(1g/cm3)(980cm/sec2) = 14.8cm=h. So the water would rise 14.8 cm up into the soil material.
@@PurdueExtension thank you for your reply. is it surface tension of the soil or the container holding the soil? and is there a table for this variable? water density varies base on the temperature of the water, so it is least dense in vapor form? gravitational acceleration is fairly constant on the Earth surface therefore, the rise nearly deduces to the inverse of the radius of the pores? this is the average radius of the pores?
i come from bonsai world, this is usefull info, no bonsai people i ever hear talk about the capillary effect on sail.
thanks from Norway.
Wow. I wish I had known this years ago, so many things make sense now. Thanks for the excellent explaination
Just blew my mind. I've been watering my potted plants from above for awhile now...
Thank you! I enjoyed your explanation.
Thanks, best video I found for my physics class
Great vid! Thank you.
irrigation+rainfall = evaporation + transpiration + runoff + leaching
Which one of these processes do Farmers really have control over during the growing season? If you have the ability to irrigate your sandy soils and water is cheap and plentiful, then you are fortunate and have some control on the left side of the equation. If you do not have irrigation, you must look at the factors on the right side of the equation to see what can be controlled or minimized to benefit your crop. Evaporation from the soil surface can be reduced with mulch or leaving crop residue on the soil surface. Transpiration is a function of the plant leaf surface area and the weather. Runoff is or should be minimal in sandy textured soils with high percolation rates.
This leaves the leaching of water out of the root zone as the #1 controllable loss of moisture to your crop. Interrupting the downward movement of moisture in your soil by installing a "smart" barrier can greatly reduce the leaching of water and nutrients. SWRT subsurface membranes detain/retain up to 90% of irrigation or rainfall in the root zone for crop use by disrupting the gravitational movement of water in the soil while still allowing excess water to percolate and do not create anaerobic soil conditions.
Thank you for the nice explanation.
Good clarification. Nice demo
Wow, it really is that simple.
great video
So this is either similar or is in fact a perk test for home building then?
How long does it take to get to the top point there on the silt tube? I am assuming that one rises fastest.
Hi, I'm interested too. Have you figured out the answer yet?
Good explanation for my geology class
does capillary rise means the rise of water table?
Nice
But I have read many papers proving that clay shows the highest capillary rise. what do you say about that?
According to our agronomists, the reason is that soils are not (except very rarely) made of just one soil type, but a mix of sand, silt, and clay. Soils that are considered “high” in clay might have 30% clay but it is the silt that is causing the capillary rise, as shown in the video.
@@PurdueExtension the pores "shutting" down by swelling is caused by the presence of expansive clay minerals (e.g. montmorilonite or another smectite; structure 2:1). If these minerals are not present (some 1:1 expand a little as well) then you may have a higher rise. Same for silt. Expansive (2:1) clay minerals may affect the capillary rise.
how high is the rise for each of these soil and how to calculate them?
Hello @C Xyooj - As the video discussed, capillary rise is greatest in silty soils (medium to fine particle sizes), and lower in both sandy (coarse particles) and clayey (very fine particles) soils. Capillary rise can be calculated with the capillary rise equation for sands and silts, but it cannot really be calculated for the clays because the flow is so slow in the clays due to the extremely small pores. For sandy and silty soils, the height (h) of water rise is determined by the largest pore sizes in the material.
The capillary rise equation is h=(2) (surface tension) / (radius of pores)(density of water)(gravitational acceleration).
So for example, for a soil material with largest pore size radius of 0.01 cm, the calculation would be:
H=(2)(72.7 g/sec2) / (0.01cm)(1g/cm3)(980cm/sec2) = 14.8cm=h.
So the water would rise 14.8 cm up into the soil material.
@@PurdueExtension thank you for your reply.
is it surface tension of the soil or the container holding the soil? and is there a table for this variable?
water density varies base on the temperature of the water, so it is least dense in vapor form?
gravitational acceleration is fairly constant on the Earth surface
therefore, the rise nearly deduces to the inverse of the radius of the pores? this is the average radius of the pores?
HI LUOA
Lli