Someone posted the following to our 'Ask the Team' forum: "What are the key tasks you must master in order to be a contributing member of this team?" I think this is an excellent question for any science research team, so I am using it as my focus for this journal entry.
Curiosity and Carbon Fluxes
You have to be interested in what you are studying, and you have to care about it. Researcher Kim Miller explained that she is particularly interested in things you cannot see and touch, such as the gases being taken in and given off by wetland soil microbes. Soil microbes are the ones who decompose the organic matter – the vegetation that has died. During this process of decomposition, the soil microbes produce gases just like we produce and breathe out gases as a by-product of our metabolism.
Soil collars isolate the area of wetland from which the carbon flux will be measured. These collars extend down about 20 cm.
The fundamental reason she is studying carbon flux – flux means change over time – is that the gas compounds carbon dioxide, CO2, and methane, CH4, trap heat in our atmosphere. The more CO2 and CH4, the warmer the atmosphere can get. This is a significant contributing factor to climate change.
To measure the carbon flux (change over time) between the wetland soil and the air directly above it, the soil collars are enclosed by these caps.
Kim's project measures the flux of both CO2 and CH4, and when the gas samples we collect are analyzed, she can calculate the ratio of CO2 to CH4. The flux of methane (the CH4) is of particular importance in this study as although much less CH4 is being given off than CO2, in the atmosphere methane traps 25 times more heat than carbon dioxide!
Gas samples are withdrawn from the enclosed space between the collar and cap right after the cap is put on, and again after 20 minutes. The two samples are then analyzed to determine the change in gas composition over time (the flux).
So to put this all together: northern wetlands are cold and wet (and beautiful, I might add). These wetlands support a lot of vegetation. When the vegetation dies, soil microbes decompose it. However, because it is cold and wet, the decomposition process is very slow. In the recent past, more carbon in the form of dead vegetation has been added to the northern wetland system than is decomposed by the soil microbes. We say that wetlands are a "carbon sink." The wetter an area is, the more likely it is that there are more methane-producing microbes.
As our overall global climate warms, conditions change for our northern wetlands. Some areas are drying, which means there will be more carbon dioxide producing soil microbes, but some areas are getting wetter, which would favor methane producing soil microbes. The information about carbon fluxes that Kim is gaining from this project will contribute to our knowledge of the process of northern wetland carbon fluxes, particularly carbon in the form of methane. At this point, the flux of methane has not been studied as much as the flux of carbon dioxide.
Kim Miller taking gas samples to determine the carbon flux (particularly methane) in Finnish wetland soils.
Wow, all that information based on just one aspect of what it takes to be a contributing team member! However, acting to satisfy your curiosity and caring about the topic you are researching really are critical. I will continue with this topic in later posts. Please keep those questions coming!
Field day bonus
Some geese flew over while we were taking measurements. They circled a few times on the wind, seemingly unhappy that we were occupying their space. Take a listen – they honk, but it is not a Canada goose honk. I wonder what species of geese are here in Finland?
http://youtu.be/OJUnMPsGkSs