First Sampling Result!

We started our first carbon dioxide gas sampling this week. If you go back in the blog to our previous post you can see Steven and I establishing the 'collar network' at the site. Now that collar network will finally got some use!

The 'collars' are used to measurement the amount of carbon dioxide gas being emitted from the soil surface. The gas is measured by placing a lid on the collar rim and using a needle to extract a gas sample every 15 minutes from the head space of the collar for an entire hour. This process follows a well known protocol in the soil science world call the "GRACEnet Protocol" (Greenhouse Gas Reduction through Agricultural Carbon Enhancement network.”) developed by the United States Department of Agriculture in 2005. Then these gas samples are put through a machine back at the lab to determine the carbon dioxide concentration in each sample. From there the concentration are run through a coding program which calculates the amount of carbon being release per each collar at each time of sampling and creates a heat map of the data (Figure 6). See the pictures below to get some examples of this process out in the field.

Figure 1: Preparing the supplies need for sample measurement, the syringes are for extracting gas samples (left) the vials are used to hold the gas samples until they can be processed in the lab (right) and the cardboard sheets are used to organize the vials until they can be processed.

Figure 2: New Crow Lab intern, Kaelin places the collar lid on the collar rim after the first gas sample has been extracted at time = 0 minutes in which the lid is not needed.

Figure 3: 15 minutes is need to wait for each collar between each sampling to make sure there has been enough build up of carbon dioxide.

Figure 4: Masters student, Casey, samples from a collar lid using a syringe

Figure 5: Research Assistant, Steven, injects a gas sample into a vial for later processing in the lab.

Figure 6: Final result! The resulting carbon flux (emitted gas) in micro-grams of carbon of carbon dioxide for the site at the final gas sampling at 60 minutes