Soil Salinity
Living organisms have a limited tolerance of salinity. You will measure the conductivity of several soil samples to determine the salinity of the soil. In addition, raise the temperature of an ionic solution to determine the effect of temperature on conductivity.
Lab Summary
In this exploration, students will use a conductivity sensor to measure the salinity of community soil samples using a standard procedure to measure electrical conductivity.
Ionic salt compounds in the soil will dissociate in aqueous solution into anions and cations, conducting electricity as the positive and negative ions travel toward oppositely charged electrodes.
Students will demonstrate the disparities in soil salinity by taking samples in diverse locations and predicting whether their soil could support common agricultural crops. In addition, students will investigate the effects of temperature on conductivity.
Downloads
- Download Free Lab (PDF, 600 KB) (598 KB, .pdf)
(student version)
Method
Use the Conductivity Sensor to measure the salinity of community soil samples using a standard procedure.
Here's What You Need
U.S. Educator prices shown.
Probeware
PASPORT Conductivity Sensor (PS-2116A) - $110
Utilizes platinum probes for greater range and improved accuracy in high & low concentrations.
PASPORT pH Sensor (PS-2102) - $79
Has a wide measurement range of 0 to 14 pH. Has a resolution of 0.01 pH. For use with PASPORT Interfaces.
Xplorer GLX (PS-2002) - $349
The Xplorer GLX is a data collection, graphing, and analysis tool designed for science students and educators.
Other Materials
- Beakers (4), 250-mL
- Wash bottle and Waste container
- Stirring Rod
- Measuring Spoons
- Hot plate
- Trowel or Digging Tool
- Water, Distilled, 1.0 L
- Liquid Fertilizer, 1 drop
- Protective Gear
- Sealable plastic bags
- Community soil samples in sealed bags
- Pen or pencil
- Permanent marking pen
