Is it water saturation?

Yes

Dear Sir,

At first, You have to calculate how much water is required to saturate the soil. You can calculate the water to be require for the full saturation of a soil by calculating the degree of saturation of that soil.

Degree of Saturation , Sr = Vw / Vv

Where, Sr= Degree of Saturation

Vw= Volume of water

Vv= Volume of air

Now, let,

Take a soil sample in core sampler and wt. of this sample is 0.7 Kg and its volume is .00035 m3. Measure the volume by measuring Hight ( h) and radius (r) by using the equation (3.14*r2h).

Place the core sampler in oven. After drying it's weight reduce to 0.6 Kg.

Now,

Mass of water in soil sample= 0.7-0.6= 0.1Kg

Volume of water (Vw)= 0.1/1000= 0.0001 m3 [Density of water=1000 Kg/m3 ]

Now calculate volume of air or void (Vv) to the following way

Ps=Ms/Vs= GsPw....................(1)

Where, Ps=Density of soil solid/ Particle

Ms=Mass of oven dry soil

Vs= Volume of soil particle of oven dry soil

Gs= Specific gravity of soil ( Ranges from 2.65-2.80 from sandy to clay)

Pw= Density of water

Now we can write from equation (1)

Vs=Ms/( Gs*Pw)

=0.6/(2.65*1000) [ Let, Gs=2.65], Pw of water=1000 Kg/m3

=0.000226 m3

Now volume of air or pore space or void in oven dry soil

Vv = Total volume of soil in core sampler- volume of soil particle

=V- Vs =0.00035-0.000226= 0.000124 m3

Now,

Degree of saturation (Sr)= Vw/Vv=0.0001/0.000124=0.806=80.6%

Now,

For 80.6% saturation of 0.6 Kg soil water is required 0.1 Kg

For 100% saturation of 0.6 Kg soil water is required =(0.1*100)/80.6

= 0.1241 Kg water

This way Please, calculate the amount of water to be required to 100% saturation of water you will be use your Pot

Let, it will be 12 Kg

Now place some soil in a core sampler from your pot soil and calculate what will be the final wt. of 12 Kg Soil after placing it in a oven by using the relative value from the core sampler

Let, 12Kg soil will be 10 Kg after oven dry

Now considering the above calculation

For 100% saturation of 0.6 Kg soil water is required 0.1241 Kg Water

For 100% saturation of 10 kg soil water is required =( 0.1241*10)/ 0.6

=2.068 Kg/L water

For, 75% Saturation= 1.551 Kg/L Water

For 50% saturation = 1.034

So, Finally you have to pour 2.068 , 1.551, 1.034 Kg/L of water in your pot for 12 Kg Soil for 100%, 75% and 50% Saturation Respectively

Dear Sir, Please Follow this steps for the calculation of water require to saturate your experimental pots at 100% ,75%, 50% and the same other rates................