Tuesday, September 29, 2015

The SERC Experience: My Summer on the Chesapeake Bay

Rather than being knee-deep in water quality research at my home base in Gainesville, I spent this past summer at the Smithsonian Environmental Research Center located in Edgewater, MD, on the iconic Chesapeake Bay. 

Research activities at SERC encompass virtually all aspects of coastal ecosystems: wetland biogeochemistry, marine biodiversity and invasions, plant and animal population dynamics, water quality, effects of global change and land use, and more! You can check out highlights of SERC research on twitter @SmithsonianEnv.

Step One: Get a GRIP
So, how did I end up in Maryland? The story begins with the National Science Foundation (NSF). Every year, NSF funds graduate studies through their Graduate Research Fellowship Program. NSF recently created a new initiative called the Graduate Research Internship Program (GRIP). NSF GRIP offers NSF Graduate Research Fellows the opportunity to expand their research and spend a few months at a national lab or federal agency. I received a NSF Graduate Research Fellowship at the beginning of my graduate studies, so I was eligible for this new internship program - I applied, and I got a GRIP! 

The Global Change Research Wetland
During my 10-week stay this summer, I joined the Biogeochemistry Lab, whose Principal Investigator is Dr. Pat Megongial. Much of the Biogeochemistry Lab’s research takes place at the Kirkpatrick Marsh, which is also referred to as the Global Change Research Wetland. The Global Change Research Wetland is the world’s premier field site for research on tidal wetland responses to global change, and has been home to experiments and observations on the interactions between salt marsh plant communities, CO2, nitrogen, and sea level for almost 30 years. Essentially, researchers at the Global Change Research Wetland are increasing our understanding of the fate tidal marshes face in a future world.

Aerial view of the Global Change Research Wetland at the Smithsonian Environmental Research Center, taken by Dr. Chuck Gallegos.

Every summer, the experimental chambers in the marsh are comprehensively surveyed. Data collected during these surveys are used to understand how experimental and natural changes influence the marsh plant community, which can then assist efforts to understand how these changes might scale to other tidal marsh systems. One of my internship goals was to get my feet wet and hands dirty in Global Change Research Wetland activities (figuratively and literally!), and I was not disappointed! In July, I had the opportunity to assist with a few aspects of the aforementioned marsh survey, including stem density and dimension measurements.

Top to bottom: in the marsh and field station (credit: SERC)

How to MarshCycle
As part of my internship, I was also graciously included in a project called MARSHCYCLE. MARSHCYCLE investigators – including Dr. Maria Tzortziou of CCNY, lead Principal Investigator, and co-Principal Investigators Drs. Pat Neale and Pat Megonigal at SERC, among other scientists – are integrating field, modeling, and remote sensing approaches to disentangle and quantify key carbon processes taking place along the wetland-estuary boundary (where land meets water). My specific role was to evaluate the hydrology of the main tidal creek flooding and draining the Global Change Research Wetland. Information about flow patterns can be used to complete mass balances of water quality constituents entering and leaving the marsh, as well as to clarify mechanisms related to the release and capture of these constituents within the marsh.

The mouth of the Global Change Research Wetland tidal creek. 
On Transducers
To carry out this analysis, the creek needed to be instrumented with flow and depth measurement devices. The selected flow meter was equipped with acoustic and pressure transducers. Acoustic transducers emit sound pulses that bounce off of particles and debris floating in the water. The instrument measures the amount of time it takes for the sound pulses to return to the acoustic transducer after having bounced off of the particles in the water, and can then calculate the velocity of water moving through the creek. This measurement principle is based on the Doppler effect. The pressure transducer measures the surrounding pressure, which corresponds to the depth of the water column. Flow can then be calculated by knowing the depth and velocity of the water.

Taking flow measurements at the Global Change Research Wetland tidal creek.
The flow meter was situated on the creek bottom about 1.5 meters below the water surface.
Collected data are still being analyzed, but we’re starting to see some interesting patterns using time series analysis approaches. Stay tuned for results in the future!

Growing in Work
This internship experience was wonderful in so many ways. I was able to get involved in SERC research and outreach happenings, gain new colleagues and mentors, work in a cutting-edge environmental research facility, learn about water resources issues in a different part of the country, and make some wonderful friends! 

Unpacking our vessel after taking a flow transect of the Rhode River.
Graduate students often don’t create time for these external opportunities because of the various pressures associated with research and school, but I can think of no better supplement to my scientist-engineer training than to have experienced a different work culture and learned from a group of world-renowned scientists outside of my immediate academic circle.

Until next time: A Chesapeake Bay reminder...

Natalie Nelson is a PhD student in Agricultural and Biological Engineering at UF. Her previous IrriGator contributions covered the Annual International Meetings of the American Society of Agricultural and Biological Engineers (here and here).