Soil carbonation (but not really)

I am Jonathan Moy, an undergraduate intern in the Agroecology lab. I work with Elizabeth de la Reguera, an MS student here, in two of her projects. Her work is largely on how saltwater intrusion in Maryland affects the carbon found in soil. We recently finished transferring four thousand switchgrass plants to UMD’s greenhouse. Later in the year, the lab will be planting the switchgrass along with other salt-tolerant plants in saltwater intruded agricultural plots to determine the carbon the plants imparted in the soil. The data from that experiment will be helpful in giving farmers in Maryland a well-supported reason to use salt-tolerant crops in their crop rotations. The project I am working on right now examines the aggregate distribution in saltwater intruded agricultural fields. Soil aggregates are important to the available nutrients to the soils [1]. We are most closely looking at soil carbon—thus the title of this post. Carbonation the way most people use it usually refers to carbon dioxide reacting with a beverage to make it effervescent. While that doesn’t happen in our soils, carbon is still very interesting in soils! The method we are using uses a series of sieves to separate the soil carbon by availability [2,3]. Essentially, the smaller the aggregates are, the less available the carbon is to the plants’ roots [2]. One of the pictures with this post shows Elizabeth displaying the second smallest sieve we use in this experiment. Fun fact: the picture also features the very first sample we processed for this experiment.

During spring break, I was given the opportunity to visit the sites that we are working on! You may not be able to tell from the picture (I’m the guy in blue), but I had a blast soil sampling. If you look really closely, you can see that I’m smiling. Those soils were the same soils that we are processing right now, so that is just one more thing to be excited about when processing my samples. Before that, I spent a lot of time in the Greenhouse seeding, thinning, and transferring switchgrass until we had four thousand switchgrass plants individually growing in deep planting plugs.

References
Ontl, T.A. et al. (2013). Topographic and Soil Influences on Root Productivity of Three Bioenergy Cropping Systems. The New Phytologist, 199, 727-737. doi: 10.1111/nph.12302

Elliott, E.T. (1986). Aggregate Structure and Carbon, Nitrogen, and Phosphorus in Native and Cultivated Soils. Soil Science Society of America Journal. 50, 627-633.

Six, J. et al. (2000). Soil Structure and Organic Matter: I. Distribution of Aggregate-Size Classes and Aggregate-Associated Carbon. Soil Science Society of America. 64, 681-689.