This fall I started working in the Agroecology lab, helping with Elizabeth de la Reguera’s study investigating the effects of saltwater intrusion on agricultural land. Hundreds of soil samples were acquired, before my time, from sites located on the Lower Eastern Shore of Maryland to test for carbon storage potential. These field samples were separated into aggregate size classes by sequentially wet sieving, a process called carbon fractionation (Six et al., 2000). The samples were then ready to be oven dried for several days.
After oven drying the aggregate sizes, I began to work with the samples. My first weeks in the lab revolved around scraping the dried soil from their tins into coin envelopes to be used later. If you saw me in the lab around this point in time you would’ve saw a seemingly never-ending mountain of tins that I’d be chipping away at, needless to say I never had to worry about having nothing to do. In addition to scraping the tins, I eventually began to prepare and measure a small amount of soil from these coin envelopes to be used for carbon and nitrogen analysis.
In a broader context, I learned from this study that not only is the amount of carbon in soil important for agricultural purposes, but where that carbon is located is just as important. I found that carbon inside of macroaggregates, which is broken down easier, tends to be more labile and can be used by crops more readily than carbon located in microaggregates (John et al., 2005).
Most days I would work individually in the lab, but that does not mean that there is no team chemistry on this project. Elizabeth communicates with me on a regular basis to ensure that I understand what is currently going on. Additionally, Dr. Tully and others in the Agroecology lab encourage me to come forward if I have any questions. This individualistic yet team-rooted environment is one of my favorite things about working in the lab and makes me excited to continue learning new things and helping on this project!
- By Zach Johnson
John, B., Yamashita, T., Ludwig, B., & Flessa, H. (2005). Storage of organic carbon in aggregate and density fractions of silty soils under different types of land use. Geoderma, 128(1-2), 63-79.
Six, J., Paustian, K., Elliott, E. T., & Combrink, C. (2000). Soil structure and organic matter I. Distribution of aggregate-size classes and aggregate-associated carbon. Soil Science Society of America Journal, 64(2), 681-689.