The Human Footprint (HF) of the Northern Appalachian/Acadian ecoregion measures the extent and relative intensity of human influence on terrestrial ecosystems at a resolution of 90 m using best available data sets on human settlement (population density, dwelling density, urban areas), access (roads, rail lines), landscape transformation (landuse/landcover, dams, mines, watersheds), and electrical power infrastructure (utility corridors). The Human Footprint is calculated by assigning Human Influence (HI) scores of 0 to 10 to geographic data layers that map features of human activity. Where 0 is no human influence (no conversion from natural state) and 10 is maximum human influence (complete conversion e.g. urban areas, road surfaces). HI scores from assigned to data layers are combined together to calculate the Human Influence Index (HII), that measures total direct human impact.
The Human Footprint is a relative measure of human impact - relative to the ecological context. The Human Footprint is calculated by normalizing the Human Influence Index (HII) within ecological subunits within the study area using the equation HFi = [(HIIi - HIImin_j) * 100] / (HIImax_j - HIImin_j) where i represents the cell and j represents the ecologic subunit of which the cell is a member.
Gillian Woolmer - Wildlife Conservation Society Canada Stephen C. Trombulak - Middlebury College Justina C. Ray - Wildlife Conservation Society Canada Patrick J. Doran - The Nature Conservancy Mark G. Anderson - The Nature Conservancy Robert F. Baldwin - Clemson University Alexis Morgan - WWF-Canada Eric W. Sanderson - Wildlife Conservation Society
The GAP Land Stewardship Classification System categories are defined as follows: Status 1: An area having permanent protection from conversion of natural land cover and a mandated management plan in operation to maintain a natural state (< 5% anthropogenic use), within which disturbance events (of natural type, frequency, intensity, and legacy) are allowed to proceed without interference, or are mimicked through management.
Status 2: An area having permanent protection from conversion of natural land cover and a mandated management plan in operation to maintain a primarily natural state, but which may receive uses or management practices that degrade the quality of existing natural communities (< 5% low intensity anthropogenic disturbance), including suppression of natural disturbance.
Status 3: An area having permanent protection from conversion of natural land cover for the majority of the area (> 50%), but subject to extractive uses (> 5%) of either a broad, low-intensity type (e.g., logging) or localized intense type (e.g., mining). It confers protection to federally listed endangered and threatened species throughout the area.