Question

why permeability in sand is more than clays​

Answer 1

Answer:

Why do they do this? Some surface soils in the area have a high clay content (very small particles), so they have high porosity but low permeability. Adding sand helps increase the average soil particle size, increasing the permeability.

Answer 2

Explanation:

Surprisingly, clay can have high porosity too because clay has a greater surface area than sand, therefore, more water can remain in the soil. ... Some surface soils in the area have a high clay content (very small particles), so they have high porosity but low permeability.