Soil Porosity Test

This test substituted water for air. To find the amount of air in the soil, we took a 400mL beaker and filled it with 200mL of packed soil and a graduated cylinder was filled with 100mL of water.

Water was continuously added until it began to pool at the surface of the soil sample.

We measured the remaining water in the graduated cylinder. Of the 100mL of water, only 17mL was not used in filling the empty air spaces in the soil sample.

This means that 83mL of the total 200mL of soil was composed of air. Again, water is substituted for soil in this procedure.

83mL water
200mL soil   =   41.5% air

This soil sample is 41.5% air