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
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.