Glossary & Important Terms
| A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T |U | V | W | X | Y | Z |
A
AGTSL3: Percent Agriculture / Grassland on Slopes greater than 3%
E
E. coli: the bacteria species Escherichia coli
ECOLI_PRED: Escherichia coli Cell Count Predictions (bacterial cells/100 ml)
Ecological Driver: An ecological element that causes a change in an organism, community, ecosystem, or other ecological component of the landscape. An ecological driver may be biotic (e.g., an invasive plant species that causes a decrease in the biological diversity of a forest) or abiotic (e.g., a fire that causes a decrease in the biological diversity of a forest)
Ecological Receptor: An ecological element that is affected (either directly or indirectly) by an ecological driver. For example, the understory plant species that are extirpated as a result of a forest fire are ecological receptors)
Endpoint: Endpoints describe a characteristic of an ecosystem of interest, and should be an ecologically relevant measurement. An endpoint can be any parameter, from a biochemical state to an ecological community's functional condition
EPA: Environmental Protection Agency
Eutrophic: Waters or soils that are rich in nutrients and have high primary productivity
Extirpated: Locally extinct
F
FGDC: The Federal Geographic Data Committee , which coordinates the development of the National Spatial Data Infrastructure
G
GIS: Geographic Information System(s)
H
HUC: Hydrologic Unit Code
K
Karst topography: A type of topography that is formed over limestone, dolomite, or gypsum by dissolution and characterized by sinkholes, caves, and underground drainage
L
Landsat : The satellite based U.S. National Aeronautics and Space Administration project that, in the late 1960s and early 1970s, endeavored to observe land features from space. The program has evolved by the launching of a total of seven satellites to date. Landsat imagery is used for a variety of earth observations
Landscape: A complex concept encompassing several definitions: For the purposes of this report, a landscape is an area containing a mosaic of land-cover "patches", i.e., distinct areas that can be defined or mapped. The traits, patterns, and structure of a specific geographic area including its biological composition, its physical environment, and its anthropogenic or social patterns
Landscape characterization: The process of documenting the traits and patterns of the essential elements of the landscape
Landscape ecology: The study of the distribution patterns of communities and ecosystems, the ecological processes that affect those patterns, and changes in pattern and process over time and space
Landscape indicator: A measurement of the landscape, calculated from mapped or remotely sensed data, used to describe some other spatial or temporal pattern(s) of land-use or land-cover across a geographic area
Landscape metric: A measurement of a component or components (e.g., patches of forest) within the landscape, which is used to characterize composition and spatial configuration of the component within the landscape (e.g., forest size, fragmentation, proximity to other land-cover types). For the purposes of this document, synonymous with a 'Landscape Ecology Metric'
Landscape unit: A reference unit (usually of area) that is being measured, mapped, or described
N
Natural Breaks: Classes are based on natural groupings of data values. Natural break points are identified by looking for groupings and patterns inherent in the data. The features are divided into classes whose boundaries are set where there are relatively large jumps in the distribution of data values
NED: National Elevation Dataset
NLCD: National Land-Cover Dataset
NWIS: National Water Information System
O
Oligotrophic: Waters or soils that are poor in nutrients and have low primary productivity
ORD: Office of Research and Development
P
PAGT: Percent Total Agriculture / Grassland
PAGTC: Land-Cover Percent Agriculture / Grassland Change
Patch: A discrete land-cover unit, for example, a "patch of forest" is a specific 25-acre wooded area in Taney County, Missouri
PBAR: Percent Barren
PCTIARD: Percent Impervious Surfaces
PDF: A document in Adobe Portable Document Format (PDF); the filename extension is .pdf; See EPA's PDF page to learn more.
PERM: Permeability (in / hr)
PFOR: Percent Forest
PFORC: Land-Cover Percent Forest Change
Primary productivity: The rate at which biomass is produced by organisms, which synthesize complex organic substances from simple inorganic substrates, such as in photosynthesis
PRISM: Parameter-elevation Regressions on Independent Slopes Model
PURB: Percent Urban
PURBC: Land-Cover Percent Urban Change
Q
Quantile: Each class contains an approximately equal number (count) of features. A quantile classification is well-suited to linearly distributed data. Because features are grouped by the number within each class, the resulting map can be misleading, in that similar features can be separated into adjacent classes, or features with widely different values can be lumped into the same class. This distortion can be minimized by increasing the number of classes
R
RAGT120: Percent Total Agriculture / Grassland within 120m of Streams
RDDENS: Road Density (km road/km²)
Reporting Unit: Any defined area (e.g., an 8-digit USGS hydrologic unit code "HUC" or portion, thereof) for which a landscape metric (e.g., percent urban) is calculated
RFOR120: Percent Forest within 120m of Streams
ROUGH: Roughness coefficient (unitless)
RURB120: Percent Urban within 120m of Streams
RUSLE: Revised Universal Soil Loss Equation
RUSLE_A_KHY: Gross Soil Erosion [RUSLE] (kg / ha / yr)
RUSLE_K: Soil surface erodibility [K factor] (unitless)
S
SEDMOD: Spatially Explicit Sediment Delivery Model
SEDMOD_KHY: Net Sediment Delivery [SEDMOD] (kg / ha / yr)
Standard Deviation: Classes show the amount a feature's attribute value varies from the mean value of the distribution. Class breaks are generated by successively adding or subtracting the standard deviation from the mean. A two-color ramp is best used to emphasize values above or below the mean. It is particularly useful in viewing spatial variability of a parameter
STATSGO: State Soil Geographic (database)
STORET: STOrage and RETrieval system
STRMDENS: Stream Density (km stream/km²)
T
TAM_PRED: Total Ammonia Concentration Predictions (mg/L)
TP_PRED: Total Phosphorus Concentration Predictions (mg/L)
W
Water-Quality Pour Point: A field-based water-quality sampling station location, for which an associated subwatershed is determined. Each 'pour point' can be considered the final exit point of surface water, from which precipitation (that falls within the associated subwatershed) exits