The Pymatuning wetlanders discussed salt marshes this morning, with a focus on plant adaptations to salinity, causes of plant community zonation, food-web structure, energy flow, and sulfur biogeochemistry. And of course, some discussion of when herbivory goes awry, with guest appearances by lesser snow geese, Littoraria snails, and nutria.
We then sampled macroinvertebrate communities at two more wetlands. We almost got the van stuck in the mud, but with 7 wetlanders pushing the van we made it. After sampling we had lunch and looked over the ice cream selection at the local ice cream place in Linesville. It seemed like a good day for ice cream to me, but the students decided that they would rather spend the time identifying macroinvertebrates in the lab. The entire afternoon was devoted to macroinvertebrate data collection.
Today was the midterm exam. The students looked a bit tired this morning. The first half of the exam was in the classroom and the second half was in the field. Word on the wetland street is that the first part was challenging, but the plant identifications were straightforward. As it should be.
We went to Geneva marsh this afternoon and began sampling macroinvertebrates as part of a comparative ecology project. We will sample marsh and shallow pond sites under open and closed canopies, and sites with and without fish. Two wetlands were sampled this afternoon, including Geneva marsh itself and a nearby pond. The students then spent the rest of the afternoon isolating the macroinvertebrates from their samples. One student in the class has been proclaiming that he really wants to see a walking-stick insect (because as he says, they don’t really want to be seen). I think he was pleasantly surprised that we did collect the “wetland-version” of this morphology today, a water-stick insect (family Nepitae).
Tomorrow we will sample another two sites and begin to identify and tally our collections.
The Pymatuning wetlanders wrapped up two weeks of the wetland ecology course today by first examining swamps and riparian wetlands and then heading out to Pymatuning Creek Marsh to collect the wells and data loggers that we installed last week. The collection of the wells proved difficult, but the students were creative and managed to recover them all.
We then visited Dr. Rick Relyea’s research laboratory where his research team told us about the interesting experimental work they are doing in ecotoxicology, community ecology, and behavioral ecology. The students had many questions, and it was nice to be able to give them direct exposure to this sort of cutting-edge research.
We returned to lab and spent the afternoon identifying and tallying our macroinvertebrate samples. We found many new macroinvertebrate types this year, and I am looking forward to seeing the results.
After discussing freshwater marsh ecology and seed banks this morning, the Pymatuning wetlanders headed into the field to sample macroinvertebrates. We will be comparing the composition of macroinvertebrate communities in several shallow ponds and marshes, at both closed-canopy and open-canopy sites, as well as shallow ponds with and without fish. We spent the afternoon picking the macroinvertebrates out of the samples, and identifying and counting them. So many bugs! Going to be more work to do tomorrow. More pictures at end…
The Pymatuning wetlanders had a chance to demonstrate their knowledge of wetland hydrology, biogeochemistry, and vegetation this morning. The first part of the exam was written and focused on the conceptual material, and the second part was in the field and focused on wetland plant identification. They seemed very prepared, although a bit tired.
We then completed a laboratory experiment examining the ability of Sphagnum moss to acidify its surroundings, and the students were able to use the results to understood how and why Sphagnum does this. This was followed by a literature-based activity examining top-down controls on Spartina productivity in salt marshes, with small groups reading and presenting the results of several recent studies to the rest of the class. The class then synthesized the results of all of the papers into a simple feedback diagram highlighting the many controls on salt marsh productivity. We ended the day by discussing our next field project, which will be focused on wetland macroinvertebrates. The students practiced their netting skills along the edge of Lake Pymatuning in preparation for tomorrow’s fieldwork.
Students in ecology (EES-152) at Lehigh University share pictures of our field activities via Twitter. Below are some highlights from a river ecology laboratory, which included one lab period of sampling, and another lab period focused on macroinvertebrate identification, quantification, and data analysis.
The Pymatuning wetlanders began this rainy Monday morning by examining adaptations of plants to the wetland environment. Hydrophyte leaf anatomy, carnivorous plants, aerenchyma tissue, venturi-induced convection, pressurized ventilation, and much more!
During lunch, Jessica Hua (the fabulous course TA) gave a presentation on the identification of some common wetland macroinvertebrates (i.e., invertebrates that are large enough to easily see with your naked eye). She was careful to emphasize which ones bite and which was do not, and I suspect that the students appreciated this information. 🙂
We then headed out in the field and began sampling the macroinvertebrate communities at several different wetlands. The students will quantify community composition at these different places, and assess the potential environmental controls on community structure. Below is a 5-minute video that highlights our sampling fun…