Measure Amount of change from natural land cover types to human land use types in the Great Lakes Basin.

Purpose This metric assesses the change in land cover/land use within the Great Lakes Basin, and may be used to infer the potential impact of land conversion on Great Lakes ecosystems.

Features This metric offers information on the presence, location, and predominance of land cover or land uses that are a direct result of human habitation and activities, as demonstrated by the use of remote-sensing and GIS data. Field-based collection of human impacts can also be accomplished by: surveys (using global positioning systems); sketches; personal interviews; and record analyses at local, county, or state offices.

Limitations This measure will need to be validated fully with thorough field sampling. The development of related impacts from human land use (e.g., using a regression model using impervious surface parameters and stream flow parameters) is an important goal, but requires uniform measurement of field parameters across a vast geographic region to determine accurate information to calibrate such models.

Interpretation This metric makes use of human impact metrics, and may be focused on land conversion that has occurred in proximity to sensitive ecosystems, e.g., wetlands. Because human activities are temporally variable and are non-linear in their spatial and temporal patterns, this metric is complex. Thus, multiple-scale, multiple-season, multiple-year analyses of human impact measures are required to develop a robust indicator. Land conversion can be more thoroughly explored and explained if linked to ecological functions (e.g., vegetation density, as it relates to uptake/accumulation/leaching of nutrient runoff). Land cover change has great potential for complicating the development of these metrics as indicators. Thus, multiple-season, multiple-year analyses of wetland-adjacent land cover are required to develop a robust indicator. The classification system for land cover types should be linked to the ecological endpoint of interest. This interpretation may vary as a result of the specificity of land cover type. For example, general-agriculture land cover types (e.g., "row crop agriculture") may be most appropriate, if considering general nutrient inputs from sheet flow into adjacent wetlands. Alternatively, data including crop types may be most appropriate if considering pesticide inputs from sheet flow into adjacent wetlands.

Comments A thorough field-sampling protocol, properly validated geographic information, and other remote-sensing-based data could lead to successful development of land conversion metrics as indicators of Great Lakes ecosystem conditions. Such an indicator could be applied to select sites, but would be most effective if used at a regional or basin-wide scale.

Metric Maps The Great Lakes Basin is mapped for the presence, wetland-proximity, and spatial extent of human-built land cover types using remote-sensing based geographic information. Human land uses may include (but are not limited to) agriculture, mines, recreational areas, and (sub)urbanization, each calculated by relevant watersheds.