Human impacts on the landscape are most severe in built environments. Restoring ecological services in the built environment requires quantifying current and post-restoration conditions. The heuristic of ecological services is very useful in conceptualizing ecosystem functions; however, measuring ecological services requires a scalar distinction in those functions. The smallest unit of ecosystem management is the catchment (roughly 1000 ha); the mid-scale area of management is the sub-basin (roughly one million ha), and the largest reasonable area of ecosystem management is the ecoregion (Omernik Level 3). Measuring ecological services at each scale demonstrates the necessity for scalar distinctions in ecosystem functions and ecological services metrics. A set of metrics for specific ecological services has been developed for each scale and demonstrated through application in the
Ozark Interior Highlands, the Illinois River and
Upper White River Basins, and three catchments.