Back in May, I received an email through the neighborhood message board that the Smithsonian Environmental Research Center was looking for volunteers to assist in their Annual Marsh Grass Census and Harvest. I wasn't sure exactly what this would entail, but I jumped at the chance to participate. I am currently working to finish my BS in Environmental Management at University of Maryland, University College and figured this would be a great way to supplement what I was learning in class and get a first hand look at Environmental Science in action.
I work full time, so I was only able to volunteer a few days each week the census/harvest was underway. After meeting in the biochemistry lab at the SERC campus on that first Thursday, we rode out to marsh and I was introduced to the Smithsonian Environmental Research Marsh. The marsh is located on the Rhode River in Edgewater, MD, near the mouth of Muddy Creek. I was given the basics of the Global Warming experiments and what the census and harvest were all about. With that established, we headed out into the unforgiving heat and out into the marsh.
SERC has spent much of the past two decades studying the effects of global warming. With the experiments in the marsh that I learned about, the focus was on how increased carbon dioxide levels would affect the marsh grasses. With rising sea levels, it is important to understand what will happen to the marshes.
Marshes act as huge filters that suck up large mounts of sediment and pollution before it reaches open waters, as well as providing habitat for plants and animals. Studying what is happening in the marshes will up us understand the condition of the environment and how it may be changing today. Human impact on the environment has led to increased CO2 being pumped into the atmosphere, which is believed to raise the average global temperature. This is believed to contribute to the rise in sea levels world wide, rising seas temperatures and increased storm activity and intensity.
Sea Levels and CO2
The experiments in the marsh were designed to examine what the effects of rising sea level and increased CO2 levels could potentially have on wetlands across the globe. Would the marsh become inundated if water levels continue to rise? Or would the plants benefit, growing larger and healthier due to more abundant CO2? In order to survive, they would need to increase soil levels to keep from being submerged as the water keeps getting higher. Plants use CO2 to "build tissue" (Langley, 2011) and more CO2 is likely to increase tissue building, a process called "the CO2 fertilization effect" (Langley, 2011). What would hamper this effect was that plants would need more nitrogen as CO2 levels increase in order to grow more robust, increase root base and raise soil levels.
By pumping in CO2 and Nitrogen gas into the chambers, under different conditions and in different amounts, scientists can measure the effects and determine what may happen to the marshes as sea levels and CO2 levels rise. These experiments have been gathering data in the marsh since the 1980's in one form or another, with three experiments currently in underway.
Each experiment consists of enclosed chambers. The small chambers and the large Phragmites chambers was where I spent my time during the harvest. (I did not spend much time involved with the large chambers since they're census and harvest was completed either before I began volunteering the first week or on the days I was not present.) Each set of chambers study different conditions, plant species, etc.
The first day was brutally hot! The temperatures were forecast to be in the 100's, so we had to be careful while out in the sun. I ended up working in the sorting tent back under the tree canopy at base camp, working with Nick Mudd.
While I was on the marsh, I recorded the data that Fred Teasley and Lillian Aoki called out to me at the small chamber site. These small chambers focused on the schoenplectus americanum plants, which are also called sedges. Studying the control environment (no chamber or added CO2) as well as the chambers with CO2 pumped in, it could be determined how much the CO2 had helped the sedges grow more robust and how much the soil levels had increased. I recorded the data while they called it out to me: number of plants, height, did it have rust spots, a broken tip or a miner (a bug that had drilled a home into the stalk). I didn't ask too many questions that first day; I just observed and took orders like a good soldier.
Fred and Lillian counted a small chamber. Fred with a handful of sedges.
I spent the majority of Friday recording data with Andrew Peresta (research Assistant) and Jim Duls (engineer). I wanted to climb into the marsh and start counting and measuring myself, but with close to 100 chambers and my inexperience, I did not do much more than record and sort. Not to mention, we were under explicit instructions NOT to step on the marsh, but to stay on the boardwalk or walkways. I decided, that since I tend to be a little accident prone and clumsy, my feet should stay out of the chamber areas and not take any chances.
Andrew (left) and Jim (right) during my second day.
The following week was much more interesting for me as I started to grasp the theories and the
functions of the experiments (not to mention it was raining and cloudy, giving us all a break from the 100 degree hear from the week before). We spent most of the second week working at the Phragmite site, which was the newer experiment that was constructed back in the winter of
2010-2011. These chambers housed a much larger array of marsh plants and continued building on the experimental data that was compiled with the small and large chambers over the years. I learned from asking the head of the phragmites experiment Tom Mozdzer that this new experiment was taking the older experiments a bit further. The Phrag chambers were further out into the marsh and focused on the phragmites marsh plants that thrive there. I called them reeds, since that's what I grew up calling them.
The phrag chambers were much more of a challenge. Being a new experiment and going through its first harvest, we all learned how best to count the control plots and the chambers themselves. With a much larger selection of plants, I again recorded data for the most part. The biggest challenge was not learning the names of the plant types; I actually picked up the terms fairly quickly. The challenge was learning to identify the different plants by sight. That took some time, but eventually I was able to tell the difference between disticholis and spartina. I can now also identify water hemp. Still, there are others that I could not identify, which kept me holding the clipboard until the last day.
Back at camp, Nick Mudd and a volunteer or two would count, measure and cataloged a sample from each chamber as they were delivered from the marsh. The samples would eventually be taken back to the lab, placed in the oven to dry them out, and then examined in the lab.
Engineer Gary Peresta, Lillian and Fred sorting at days end Far Above: Phragmites Chamber / Above: Large Chamber
What the data has shown is that many marsh plants will grow faster, which in turn makes new soil faster. The larger plants and more developed roots bases, coupled with higher soil levels, show that the marshes are capable of keeping pace with rising sea levels, under certain conditions. In the large chambers, the added nitrogen also showed that some plants, like distocholis and spartina that do not respond to higher CO2 levels like the sedges, grow like crazy with the addition of nitrogen into their environment. The phragmites chambers were developed to further study this climate change data, building on what has been learned so far.
Aside from the enormous spiders that camped out in the tent during sorting and the biting flies out on the marsh, I had an absolute blast! It was quiet, peaceful and I was able to apply what I had learned since coming back to school in a real-time science environment. Taking a class on Urban Watersheds helped me understand the effects of global climate change and urbanization that has threatened the Chesapeake Bay and waters around the world. Having grown up on the Chesapeake, I was introduced to science and terms that I recognized but had not truly understood.
For instance, Tom Mozdzer told me that their is native phragmites and another type that was an invasive type of phragmites in the region. He also told me that the largest concentration of the invasive phragmities in the Chesapeake region was found in Chesapeake Beach, where I grew up. I found everyone I worked with to be nice, helpful and very patient when my questions began and did not stop.
SERC has numerous different labs that study various aspects of the environment. My time on the marsh was focused on the marsh. I hope to continue to volunteer at SERC in the future and I am also considering applying for an internship next summer.
Above: Me at base camp. Above right: The northern most american alligator?
If you would like to learn more about the ongoing work at SERC or internship and volunteering opportunities, visit the link below follow. If you want to follow me here and my future posts, please click the link at the top of the page.
Acknowledgements:
Thanks to Fred, Nick, Lillian, Kate, Eva, Gary, Jim, Andrew, Tom, Petey and Pat for welcoming me and giving me the chance to help out with this years harvest. I truly had a blast and look forward to being able to help out again!
http://www.serc.si.edu/
http://serc.si.edu/labs/biogeochem/index.aspx
Sources:
Langley, A., Megonigal, P. (July 2011). "Ecosystem response to elevated CO2 levels limited by nitrogen-induced plant species shift". Nature Online. Retrieved on August 4, 2011 from: http://www.nature.com/nature/journal/v466/n7302/full/nature09176.html
