Variable

Acronym and Description (if needed)

Land cover composition

Percent Composition by Class

%CLASS

Median Class Density

AREA_MD_class; area in land use

Range in Class Density

AREA_RA_class; range in area in land use

Modified Simpson’s Diversity Index

MSIDI; landscape; quantify diversity at the landscape level

Patch Richness Density

PRD; landscape; number of patch types present

Land cover configuration

Forest Fragmentation Index

FRAG; See Riitters et al. (2000)

Median Patch Size

PATCH_class; class variable

Median Perimeter to Area Ratio

PARA_MD_class; class variable; equals ratio of the patch perimeter (m) to area (m²).

Perimeter to Area Ratio Range

PARA_RA_class; class; measure of variability in the PARA ratio.

Median Shape Index

SHAPE_MD_class; class; measures the complexity of patch shape compared to a standard shape (square) of the same size; alleviates the size dependency problem of PARA

Shape Index Range

SHAPE_RA_class; class; a measure of the variety of land use class shapes.  Less variety likely related to human modification of landscape (e.g., row crop field shapes are highly similar)

Aggregation Index

AI_class; class.  Percentage based on the ratio of observed number of like adjacencies; a measure of contagion.

Mass Fractal Dimension

MFRAC; class; tendency of patch types to be spatially aggregated.  Measures contagion or interspersion of a land use class; varies between 0 and 2.

Perimeter to Area Fractal Dimension

PAFRAC_class; class; describes how patch perimeter increases per unit increase in patch area

Interspersion and Juxtaposition Index

IJI; class; a measure of patch adjacency

Cohesion

COHESION_class; class; connectivity of habitat as perceived by organisms dispersing in binary landscapes

Median Core Area Density

CORE_MD; class; area of land use patch after elimination of edge

Range in Core Area Density

CORE_RA; class; variability in area unaffected by edge

Median Proximity

PROX_MD_class; class; size and proximity of all patches whose edges are within a specified search radius of the focal patch

Range in Proximity

PROX_RA_class; class

Median Perimeter to Area Ratio

PARA_MD_land; landscape; as for class, but for entire landscape, irrespective of land use

Range in Perimeter to Area Ratio

PARA_RA_land; landscape; as for class, but for entire landscape, irrespective of land use

Median Shape Index

SHAPE_MD_land; landscape; as for class, but for entire landscape, irrespective of land use

Range in Shape Index

SHAPE_RA_land; landscape; as for class, but for entire landscape, irrespective of land use

Aggegration Index

AI_land; landscape; as for class, but for entire landscape, irrespective of land use

Contagion

CONTAG; landscape; probability of finding a cell of type i next to a cell of type j, based on cell adjacencies

Perimeter to Area Fractal Dimension

PAFRAC_land; landscape; as for class, but for entire landscape, irrespective of land use

Cohesion

COHESION_land; landscape; as for class, but for entire landscape, irrespective of land use

Median Core Area Density

CORE_MD_land; landscape; as for class, but for entire landscape, irrespective of land use

Range in Core Area Density

CORE_RA_land; landscape; as for class, but for entire landscape, irrespective of land use

Median Proximity

PROX_MD_land; landscape; as for class, but for entire landscape, irrespective of land use

Range in Proximity

PROX_RA_land; landscape; as for class, but for entire landscape, irrespective of land use

Topography

Elevation

ELEV

Slope (˚)

SLP

Aspect

AZ; azimuth from N in degrees

Ruggedness Index (250 m window)

RUG₂₅₀; Standard Deviation of Elevation within 250 m moving window

Ruggedness Index (500 m window)

RUG₅₀₀; Standard Deviation of Elevation within 500 m moving window

Ruggedness Index (1,000 m window)

RUG_1,000; Standard Deviation of Elevation within 1,000 m moving window

Topographic Index (250 m window)

TOPO₂₅₀; Difference in Elevation between focal cell and mean within 250 m window

Topographic Index (500 m window)

TOPO₅₀₀; Difference in Elevation between focal cell and mean within 500 m window

Topographic Index (1,000 m window)

TOPO_1,000; Difference in Elevation between focal cell and mean within 1,000 m window

Topographic Wetness Index

WET; ln(Catchment Area/tangent of the slope angle);

“Stream Power” Index

POW; Aspect x Slope%

Mean Angular Deviation of Aspect

MAD; variability in aspect

Mean Stream Density

STREAM

Mean Proximity to Stream

PROX_Stream

Climate

Annual Mean Temperature

TEMP_MN

Mean Diurnal Temperature Range

TEMP_RA; Max Temperature of Warmest Month- Min Temperature of Coldest Month

Isothermality

ISO; Mean Diurnal Range/Temperature Annual Range

Temperature Seasonality

TEMP_CV; Coefficient of Variation in Temperature

Max Temperature of Warmest Month

TEMP_MAX

Min Temperature of Coldest Month

TEMP_MIN

Mean Temperature of Wettest Quarter

WTEMP_MN; For wettest 3 months

Mean Temperature of Driest Quarter

DTEMP_MN; For driest 3 months

Mean Temperature of Warmest Quarter

HTEMP_MN; For warmest 3 months

Mean Temperature of Coldest Quarter

CTEMP_MN; For coldest 3 months

Annual Precipitation

PRCP

Precipitation of Wettest Month

PRCP_MAX

Precipitation of Driest Month

PRCP_DRY

Precipitation Seasonality

PRCP_CV; Coefficient of Variation in Precipitation

Precipitation of Wettest Quarter

WPRCP

Precipitation of Driest Quarter

DPRCP

Precipitation of Warmest Quarter

HPRCP

Precipitation of Coldest Quarter

CPRCP

Day of year (number) for start of growing season

GROWST

Day of year (number) for end of growing season

GROWEND

Number of days of growing season

GROWDAYS

Total precipitation for the 1st six weeks of the growing season

PRCP_6GRW

Total precipitation for the growing season

PRCP_GROW

Growing degree days above base temperature for 3 months prior to the start of the growing season

DEG_PGRW

Growing degree days above base temperature for the 1st six weeks of the growing season

DEG_6GRW

Growing degree days above base temperature for the growing season

DEG_GROW

Mean temperature for the growing season

TEMP_GROW

Temperature range for the growing season

TEMP_RAGR

Potential Human Disturbance

Mean Road Density

ROAD

Mean Human Density

HUMAN; Mean county-level human population density