Fragmented
Being divided or convoluted into distinct parts, rather than entire. In
EMAP, the spatial fragmentation of resources and the spatial/temporal fragmentation of resource attributes affect the precision of
certain population statistics, so that attention must be given to this
state.
Frame
A representation of a population, used to implement a sampling
strategy as, for example, (1) a list frame that lists the identifying
units in the population, for instance, a list of all the lakes in the
United States between 10 and 2000 ha, or (2) an area frame that
consists of explicit descriptions of a partition of the areal extent of
an areal universe like the NASS frame.
Frame, conceptual
An explicit definition of a frame that does not involve a tangible
realization.
Geographic information
system (GIS)
A collection of computer hardware, software, and geographic data
designed to capture, store, update, manipulate, analyze, and display
geographically referenced data.
Great Lakes
In EMAP, the resource that encompasses the five Great Lakes –
Superior, Michigan, Huron, Erie, and Ontario, including river
mouths up to the maximum extent of lake influence; wetlands
contiguous to the lakes; and the connecting channels, Lake
St. Clair, and the upper portion of the St. Lawrence Seaway.
Grid
A data structure commonly used to represent map features. A
cellular-based data structure composed of cells or pixels arranged
in rows and columns (also called a “raster”).
Grid enhancement
Increasing the grid density, a method for augmenting the sample.
When the sample size is too small, as will occur for rare resources,
the grid density may be increased in order to obtain a sample size
adequate for population description. Grid enhancement is one
method of producing an augmented sample.
Grid, hierarchical
Having nested levels and structure, the density of the EMAP grid is
readily increased or reduced in a regular manner into hierarchical
levels of density. Adjacent levels may differ in density by a variety
of factors: 3, 4, 7, or many functions of these base factors. The grid
of points at one level will be contained in the grid at a higher
density.
Grid randomization
The process of randomly positioning the grid so that each (discrete)
unit of area of fixed size is equally likely to contain a grid point.
This process is the basis for the probability sample designation for
EMAP monitoring.
Grid, triangular (EMAP)
A lattice of points in exact equilateral triangular structure on a plane.
The EMAP grid points are 27.1 km apart.
Habitat
“The place where a population (e.g., human, animal, plant, microorganism) lives and its surroundings, both living and non-living.”
Heuristic method
In EMAP, a process for exploring and organizing information to
conceptually discover and describe or postulate relationships
among indicator variables and key processes of an ecosystem or
resource.
Hierarchical geometric
decomposition
The mathematical process of breaking down a geometric structure
into component parts. In the EMAP grid, the process by which the
triangular grid is subdivided into higher density grids is hierarchical
geometric decomposition. Related notions are enhancement and
disaggregation; the opposite notion is composition of components
into a larger whole.
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Being divided or convoluted into distinct parts, rather than entire. In
EMAP, the spatial fragmentation of resources and the spatial/temporal fragmentation of resource attributes affect the precision of
certain population statistics, so that attention must be given to this
state.
Frame
A representation of a population, used to implement a sampling
strategy as, for example, (1) a list frame that lists the identifying
units in the population, for instance, a list of all the lakes in the
United States between 10 and 2000 ha, or (2) an area frame that
consists of explicit descriptions of a partition of the areal extent of
an areal universe like the NASS frame.
Frame, conceptual
An explicit definition of a frame that does not involve a tangible
realization.
Geographic information
system (GIS)
A collection of computer hardware, software, and geographic data
designed to capture, store, update, manipulate, analyze, and display
geographically referenced data.
Great Lakes
In EMAP, the resource that encompasses the five Great Lakes –
Superior, Michigan, Huron, Erie, and Ontario, including river
mouths up to the maximum extent of lake influence; wetlands
contiguous to the lakes; and the connecting channels, Lake
St. Clair, and the upper portion of the St. Lawrence Seaway.
Grid
A data structure commonly used to represent map features. A
cellular-based data structure composed of cells or pixels arranged
in rows and columns (also called a “raster”).
Grid enhancement
Increasing the grid density, a method for augmenting the sample.
When the sample size is too small, as will occur for rare resources,
the grid density may be increased in order to obtain a sample size
adequate for population description. Grid enhancement is one
method of producing an augmented sample.
Grid, hierarchical
Having nested levels and structure, the density of the EMAP grid is
readily increased or reduced in a regular manner into hierarchical
levels of density. Adjacent levels may differ in density by a variety
of factors: 3, 4, 7, or many functions of these base factors. The grid
of points at one level will be contained in the grid at a higher
density.
Grid randomization
The process of randomly positioning the grid so that each (discrete)
unit of area of fixed size is equally likely to contain a grid point.
This process is the basis for the probability sample designation for
EMAP monitoring.
Grid, triangular (EMAP)
A lattice of points in exact equilateral triangular structure on a plane.
The EMAP grid points are 27.1 km apart.
Habitat
“The place where a population (e.g., human, animal, plant, microorganism) lives and its surroundings, both living and non-living.”
Heuristic method
In EMAP, a process for exploring and organizing information to
conceptually discover and describe or postulate relationships
among indicator variables and key processes of an ecosystem or
resource.
Hierarchical geometric
decomposition
The mathematical process of breaking down a geometric structure
into component parts. In the EMAP grid, the process by which the
triangular grid is subdivided into higher density grids is hierarchical
geometric decomposition. Related notions are enhancement and
disaggregation; the opposite notion is composition of components
into a larger whole.
224
S. O. Darkwah et al.