Project Description  |
The International Alvar Conservation Initiative is a collaborative effort aimed at providing a unified, consistent approach to understanding and conserving this rare and vulnerable Great Lakes ecosystem. The Alvar Initiative has been coordinated by the Great Lakes Program of The Nature Conservancy (TNC). Individual projects related to the Initiative were coordinated through annual meetings and ongoing discussions of the Alvar Working Group, a forum involving over 50 collaborators from government and non-government organizations and universities.
When the Alvar Initiative project began in the mid-1990s, there were numerous descriptions and classifications of alvar plant communities in use in Ontario, New York, and Michigan. It was difficult, however, to compare the results of the different studies, because they used different criteria to sample and describe the plant communities. So an important objective of the Alvar Initiative was to provide consistency by developing a uniform sampling methodology for gathering vegetation data, using these methods to survey a wide variety of alvar sites across the Great Lakes region, and then using results of these field studies to develop a single regional classification of alvar community types.
This new classification provides the basic inventory data to compare alvar sites across state and international boundaries so that regional conservation priorities for alvar sites can be identified. Altogether 103 survey sites were visited as part of Alvar Initiative field surveys, and data on an additional 18 sites that had been previously surveyed were compiled from collaborators. Together, these included 27 sites in Michigan, 72 in Ontario, 10 in New York, four in Ohio, five in Quebec, one in Wisconsin, and two in Illinois. Seven of the Ontario sites were too small or disturbed to be included in our community summaries. The Illinois sites were identified as closely related to alvar, but not alvar under our definition. The Quebec sites were not visited as part of this project and deserve further study. (During 1998, Quebec botanists initiated a floristic survey of the Outaouais region and identified 16 alvar sites, mostly near the Ottawa River.)
The community inventory methods were designed to gather two kinds of data: basic inventory data, and preliminary research data on ecological processes.
Quantitative data were recorded from 85 plots, each 10 m by 10 m square, which were selected to represent the best examples of the variety of alvar communities observed during field surveys. Within the plot, the surveyor noted all species in each layer of vegetation present (e.g. trees, tall shrubs, short shrubs, herbs, nonvascular plants) and the percentage of cover for each layer within the boundaries of the plot. Environmental data such as soil depth were also recorded for each plot.
Data from the 85 plots and 120 species lists were entered in spreadsheets and evaluated using standard community analysis software in the PCORD set of programs. These results were discussed by a small group of collaborators, including Carol Reschke, Wasyl Bakowsky, Pat Comer, Judith Jones, Don Faber-Langendoen, Don Cuddy, and Bruce Gilman, to develop a final recommended classification of alvar communities. The scientific names of the communities were adjusted to be consistent with the U.S. National Vegetation Classification system. Since the national classification community names have not yet been incorporated into all the state or provincial heritage databases, nor reviewed by the Canadian NVC partners, a cross-referencing table with the corresponding state or provincial community names is provided. While the community classification arrived at through the International Alvar Conservation Initiative provides a framework to describe and evaluate alvar sites in the Great Lakes basin, other systems may provide useful definitions at a more detailed level. The overall project is summarized in: Reschke, C., R. Reid, J. Jones, T. Feeney, and H. Potter. 1999. Conserving Great Lakes alvars: final technical report of the International Alvar Conservation Initiative. The Nature Conservancy, Chicago, Illinois, USA. 230 pp.
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