How to Detect Anions in Soil

Clean the electrodes (probes) of the electrical conductivity meter by rinsing them with deionized water. Tap water contains ions from soil and pipes. During an electrical conductivity test, the water ions can change places with other ions in the soil and change the results. Blot the probes dry with a lab cleaning tissue.

Choose a standard solution with a known electrical conductivity close to the EC that you believe your soil will be. A standard solution is a mixture of evenly distributed substances with a known concentration. Change the setting on the EC meter to "calibrate." There are multiple ways to calibrate meters. Follow the manufacturer's instructions for calibrating the EC meter with the standard solution.

Change the EC meter from "calibrate" to "measure." Insert the probe into the solution, and wait until the meter stabilizes to verify the electrical conductivity of the standard solution.

Clean the probes again, rinsing them with deionized water. Blot the probes dry with a lab cleaning tissue.

Insert the probes into the soil sample in the measure mode. The anions increase the conductivity of the water in the soil. Allow time for the meter reading to stabilize. If the meter does not automatically take the temperature of the sample into account, adjust the knob on the meter according to manufacturer's directions. Temperature is important for accurate readings. As the temperature increases, so does the resistance of the conducting metal in the probe.