Bob and I spent the last week finishing up the soil analysis at the Arboretum. Due to a broken still we were unable to complete the pH and electrical conductivity analysis for the samples, as both of these measurements require the soil sample to be in solution with destilled deionized water. I’ll complete these measurements in January, when I return from study abroad. But since we had some time to kill while the soil samples were cooking, we got to take some beautiful walks at the Arboretum!
They also have a totally awesome jungle gym that I was not too proud to play on. Plus, there was an exhibit of giant Lego sculptures, and one was of a Galapagos tortoise and finch! (coughcough follow my study abroad blog in Ecuador this quarter coughcough)!
On Friday we watched Taran, Meghan, and Alyssa give presentations on their projects with the REUs and they were totally awesome! Super super proud of all of them <3 Taran won the prize for best poster too! And we all got field guides from Evelyn and Becky 🙂
Now down to the deliverables: what did I learn from this summer? Well, lemme tell you…here’s a small excerpt from my wrap-up paper for the URG.
While I cannot correlate the phylogenetic diversity of the prairie plants to their soil yet, I nevertheless have at this point been able to notice a variety of interesting trends in my soil data. For the purposes of viewing these trends, I have created two charts of my data, with the average GSM and LOI for each of the 18 sites. These charts generally mirror each other, with sites with high moisture similarly having high organic matter. Since I had no experience with soil science prior to this project, this correlation was incredibly exciting to me until I looked at a textbook and found that the connection is not unique to my soil. The organic matter is the part of the soil that retains water, and thus the higher the organic matter, the higher the water content. My data is therefore consistent with known trends, increasing my confidence in its accuracy. The lowest GSM/LOI averages were at the 41st St Bioretention, a restoration in the Chicago Park District. This site was between the beach and Lake Shore Drive, making for generally dry, sandy soil. The highest GSM/LOI averages by far came from Harvey Creek, in Sandwich, IL. This soil was incredibly dark, almost black, and reminded me of fully decomposed compost. Sure enough it had very high SOM. Although I have not found out much about the history of this site, besides that it was privately owned, it was in a dip in the land that may retain water, increasing decomposition and thus SOM.
In addition to the soil research, I learned much more about restoration practices, in prairies and in general, than I had ever known before. The key takeaway that I got was this: ecosystem restoration is really hard. I had assumed that once you created the restored ecosystem, you could leave it alone to be wild again. In reality, a restored area requires diligent maintenance in order to retain the qualities of the target ecosystem. A large part of maintenance is repeatedly removing invasives, either by pulling/mowing them, spraying them, or, in the case of prairies, doing a controlled burn. Restoring a site is a never-ending project, not a quick fix.
Thanks so much for reading!