Ecoregions denote areas of general similarity in ecosystems
and in the type, quality, and quantity of environmental resources. They are designed to serve as a spatial framework
for the research, assessment, management, and monitoring of
ecosystems and ecosystem components. These general purpose regions are critical for structuring and implementing
ecosystem management strategies across federal agencies, state agencies, and non-governmental organizations that are
responsible for different types of resources within the same geographical areas. The approach used to compile this map is
based on the premise that ecological regions can be identified through the analysis of patterns of biotic and abiotic
phenomena, including geology, physiography, vegetation, climate, soils, land use, wildlife, and hydrology. The relative
importance of each characteristic varies from one ecological region to another regardless of the hierarchical level. The
Ecoregions of Michigan map was compiled at a scale of 1:250,000, as part of the US EPA framework of ecological regions.
Although there have been differences in conceptual approaches and mapping methodologies used by the USDA Forest
Service, USDA NRCS, and US EPA to develop the most common ecoregion-type frameworks, collaboration on refinement
of these frameworks is a step toward attaining consensus and consistency in ecoregion frameworks for the entire nation.
Comments regarding this map should be addressed to James Omernik, U.S. Geological Survey, 200 SW 35th Street,
Corvallis, OR 97333, (541) 754-4458, [email protected]; or Sandy Bryce, Dynamac Corp., c/o US EPA, 200 SW
35th Street, Corvallis, OR 97333, (541) 754-4788, [email protected].
