Science Buddies: "Ask an Expert"

I am doing my project on testing retention of salinity in salt after watering with different concentrations of salt water. I wanted to use arid soil as salinity is an agricultural problem in arid regions. However, I went to my local nursery and could not find any. Can you advise on where to purchase arid soil?

Also, I will drain water and different depths of my planter and then use an electric conductivity probe to measure salinity. Would the logic be that the more salt in the drainage, the less that remained in the soil or the more salt in the drained water, the more in the soil?

Hi!

This is an interesting experiment. For your first question, I would check with a Home Depot or local landscaping supply store to see if they have arid soil.

As for your second question, the more salt in the drainage would indicate that less remained in the soil. After draining the water, the salt remains would be any salt that was not absorbed by the soil, so you would need to subtract this measurement from the total salinity of the original saltwater to find the amount of salt absorbed by the soil. Be sure to measure the salinity of your soil prior to adding the saltwater to ensure accurate results.

Let us know if you have any other questions!

Good luck with your project,
Chloe