Wetland ecology at Pymatuning Laboratory of Ecology – Day 7
Salt Marsh Ecology. Day 7 of wetland ecology began with a detailed look at the ecology of salt marshes, including the vegetation zonation that commonly emerges along the salinty, nutrient, and flooding gradient from the ocean to the upland. Although the physical environment directly controls much of the zonation patterns, they are also the result of competitive dynamics among plant species. We discussed how anthropogenic nutrient loading alters these competitive dynamics, and may result in the compression or complete elimination of some vegetation zones, particularly the highly diverse high-marsh environment. We also briefly talked about the detritus-based food webs that characterize salt marshes and then examined a few case studies where herbivory has played a particularly important role in shaping these systems, such as the trophic cascades caused by population expansions of particular species (e.g.,lesser snow geese, Littorina snails, nutria).
Coastal Processes and Great Lakes Wetlands. We then drove up to Presque Isle Peninsula to observe the dynamic environment that characterizes coastal regions, and talked a bit about how the natural processes of deposition and erosion create and destroy wetlands in this setting. We walked out to Gull point to observe the youngest land surface on the peninsula – it is only a few decades old. The hike meandered through Phragmites-dominated wetlands, which seemed fitting after the morning lecture. As we walked, the students were hollering out common names and scientific names of wetland plants in preparation for the exam tomorrow…they made me proud. Some pictures below.
PLE Day 7, a set on Flickr.