Encroachment of Typha Stands on Open Fen Communities: Distinguishing Mechanisms Maintaining Diversity in Coastal WetlandsEPA Grant Number: F6F60550
Title: Encroachment of Typha Stands on Open Fen Communities: Distinguishing Mechanisms Maintaining Diversity in Coastal Wetlands
Investigators: Distler, Matthew T.
Institution: SUNY College of Environmental Science and Forestry
EPA Project Officer: Zambrana, Jose
Project Period: September 1, 2006 through September 1, 2008
Project Amount: $102,292
RFA: GRO Fellowships for Graduate Environmental Study (2006) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Ecological Indicators/Assessment/Restoration , Fellowship - Terrestrial Ecology and Ecosystems
The primary objectives of this research are to describe the long-term development of coastal Lake Ontario and inland fens and to determine whether the recent expansion of dense cattail (Typha) stands in coastal wetlands is part of a historical pattern or represents a novel change to these ecosystems, perhaps related to Lake Ontario water level regulation and increased nutrient levels in coastal wetlands. Analysis will focus on the stability of diverse fen communities in coastal and inland wetlands and the impact of historical disturbances in these wetlands, particularly fire and flooding. Additional work will be directed at more accurately describing the timing and rate of cattail encroachment in Lake Ontario wetlands. Finally, the viable wetland seed bank will be assessed in areas invaded by cattail and in uninvaded fen areas in order to evaluate the restoration and regeneration potential in these dense cattail areas.
Plant macrofossil analysis of deep peat cores will be used to describe the development and disturbance history of inland and coastal wetlands. A single core will be analyzed in detail from each of three coastal wetlands and two inland wetlands to characterize the changes in plant communities over time and determine the differences between inland and coastal patterns of development. Additional peat cores from these and three other coastal and inland wetlands will be taken from three different landscape positions and assessed for major stratigraphic changes, allowing spatial comparisons of historical cattail dominance or other major changes. Aerial photographs from 1938 through 2000 will be rectified and the major vegetation zones digitized in ArcGIS software to analyze the changes in cattail and other communities over that time period. The wetland seed bank will be assessed through a greenhouse germination study. Shallow peat samples will be taken along transects representing a gradient of cattail stand age to determine the relationship between fen plant propagule composition and age.
Knowledge of the disturbance history and past resilience of coastal fen communities will help managers to better predict the effectiveness of proposed Lake Ontario water level regimes. This study will also help ascertain to what degree cattail encroachment has changed the regenerative abilities of the fen community. In general, elucidation of long term processes will serve as a framework for prioritizing management actions and undertaking restoration of degraded communities.