March 26, 2004: Trip to Old Woman Creek

Posted: Fri Apr 09, 2004 3:03 am

March 26
11:15 p.m.

For years, scientists have known about the important role that wetlands play in filtering the water that ends up in streams, rivers and lakes. Yet after all these years, we still don’t know how. The purpose of this project is to try to discover how wetlands in general and estuaries in particular break down organic pollutants.

We will travel to Old Woman Creek National Estuarine Research Reserve near the southernmost point of Lake Erie to do our work.

What is an estuary and why are they important?
a) http://www.estuaries.org/
b) http://www.estuaries.gov/
c) http://www.whatsanestuary.com/

Where are we working?
http://www.dnr.state.oh.us/dnap/owc/default.htm

How do we do our work?
We left Columbus this morning around 8:00 a.m. and arrived at Old Woman Creek around 11:00 a.m. After a quick tour of the Visitor Center and the labs, we grabbed a bite to eat at a local restaurant and returned to the reserve to collect a sample core.

1)Fit corer onto extender:

a. Alé tried first, then Yo gave it a shot… The tube hadn’t been used for a couple of years and had been stored on its side. A seemingly trivial point, but the plastic had deformed and become slightly oval-shaped; it no longer fit on the extender. Fortunately, we had a replacement.

b.The intrepid field workers set out.

2)Take boat to appropriate location

a.The field workers look for locations rich with organic matter (limited amounts of sand in the upper sediment layers).

b.The Canadian geese honked and flapped away.
c. The carp slapped their tails on the surface of the water (but this camera is not good enough to get a picture of it!)

3) Plunge the corer into the sediment under the water

a.author’s note: the water is pretty shallow here, but you wouldn’t want to walk in it… you’d sink in mud up to your waist and would have a very tricky time getting out. Dave, our guide and a researcher at OWC, told us that he hesitates to strap on waders in the event that he needs to make a quick exit from his boots.

4) Take the corer out and cap both ends. Exposure to oxygen will change the chemistry in the different layers of the core—we want to make sure oxygen doesn’t change anything so we can study sediment conditions as they really exist! Therefore, care must be taken to keep the oxygen out.

5) When you get back to the lab, attach the corer to the extruder, and use a ratchet to squeeze the sediment core. This will force water out of the sediment pore spaces. We will use this water to understand sediment porewater chemistry.

6) Remove a screw from the corer, attach a syringe (oops! we forgot a necessary attachment in Columbus! Luckily, today was a practice run; and it is precisely this type of problem that practice runs address!) and draw out the porewater. Careful not to get splattered in the face by high-pressure mud.

7) Sediment porewater will be tested in an oxygen-free, argon-filled, positive-pressure environment.
a. oxygen-free for reasons noted above
b. argon-filled: argon is a non-reactive gas (do you know why?) that is heavier than air and pushes remaining air out of the way (a bit like carbon dioxide filling up the bottom of a fish tank filled with baking soda and vinegar)
c. positive-pressure: in the event that there is a leak, the air in the area wants to get out, not get in.

8 ) Clean up
a. remove the corer from the extruder
b. remove the cap from one end
c. use Newton’s first law to remove the mud (like ketchup, mud in motion stays in motion even if the container it is in comes to a stop)
i. there are contests to see who can fling the mud the farthest.
ii. predictably, Yo won this round (he’s had the most practice)
iii. my bets are on Alé and Kaelin; by the time they’re finished with their research here this summer; they’ll be taking LOTS of samples.

Things to think about
Field work is exciting for many reasons; you get to visit exotic places; your work is a vital step in the process of adding to the body of scientific knowledge; and you get to play outside with really smart people and talk about important ideas.

To be sure, there are challenges:
* weather can be uncomfortable (fortunately, it was a warm rain!) or dangerous (we had to postpone our data collection until the morning’s strong winds died down)
* equipment may not work as planned, requiring McGuiver-esque solutions involving duct tape and wire hangers and a trip to the hardware store.
* collecting the necessary quantity and quality of data may be repetitious (i.e., a little boring)

Luckily the importance of the work and drive to better understand the world in which we live makes these challenges easy to overcome.