Measuring CO2 Production Using Soda Lime:

Soil Moisture Content Data Form

For use with Protocol 8b: Determining Moisture Content

Complete one form for each soil sample.

Name(s)  _____________________________                       Date  _______________

Soil sample ID number ____________________________________________

Soil sampling location _____________________________________________

Type of area sampled (e.g., forest, schoolyard) _________________________

Date soil sample was collected  _____________________________________

Describe the soil sample (e.g., number and size of rocks and roots in sample; did the soil appear to be very wet or very dry?)

Was the soil sample well mixed?                                   ______________________

Date and time soil subsample placed in drying oven                   ______________________

Date and time soil subsample removed from drying oven            ______________________

or, time and power level required to dry subsample in microwave ______________

Protocol 8b, Part 1: Determine percent moisture, using a subsample.

Step 2: Weight of beaker = _____________ g.

Step 3:

 wet wt of soil = combined wt of beaker and soil – wt of beaker = ____________ g – ____________ g = ____________ g

Step 5:

 dry wt of subsample = combined wt of beaker and soil after drying – wt of beaker = ____________ g – ____________ g = ____________ g

Step 6:

 moisture content  = wet wt - dry wt          wet wt = _____g - ____g          _____g moisture content  = ___________

This result is expressed in decimal form for use in dry weight and CO2 calculations. To express as a percentage instead, simply multiply by 100.

Part 2: Adjust total sample to 50% moisture, if needed.

Step 1: Total soil weight = ______________ g

Step 2:

 actual water wt of full sample = total soil wt of full sample x moisture content of subsample = __________ g x __________ = __________ g

Step 3:

 dry wt of full sample = total soil wt of full sample – actual water wt of full sample = _________ g – _________ g = _________ g

Step 4:

 wt of water to be added = desired water wt – actual water wt = ______ g – ______ g = ______ g