How does over-irrigation damaging to soil? a. it reduces the amount of organic material in soil.. b. it results in the accumulation of salt near the soil surface.. c. it increases the acidity of soil.. d. it removes water from the water table.

The correct answer is - b. It results in the accumulation of salt near the soil surface.

As for most things where we have the unwritten rule that everything should be done with measure and to much good turns out to be bad, it's the same with the irrigation, if it's with measure than it's very helpful but if it's too much it causes damage. When there's too much water on the soil the big amount of water causes both direct and indirect accumulation of salt near the surface of the soil. The direct causing is that the water itself very often contains material that has salt in it, so it brings and deposits salt on the soil. The indirect causing is that too much water is very often striping the upper layer of the soil so the lower parts are coming very close to the surface and those parts usually contain bigger amounts of salt in them.