frame; they may correspond to resource units, or they may be
artificial units constructed for the sole purpose of the sampling
design.
Science Advisory Board
(SAB)
A peer review panel internal to USEPA. The Ecological Effects
Committee of the SAB conducts reviews of EMAP’s overall program and the conceptual framework for integrating EMAP with
ORD’s Ecological Risk Assessment program. Preparation for SAB
reviews is coordinated by the director of the Office of Modeling,
Monitoring Systems, and Quality Assurance (OMMSQA); the
assistant administrator for ORD is responsible for funding. SAB
review is considered level 1 peer review.
Spatial model
A set of rules and procedures for conducting spatial analysis to
derive new information that can be analyzed to aid in problem
solving and planning.
Spatial statistics
Statistical methodology and theory that accounts for spatial aspects
of a spatially distributed dataset. Conventional population estimation does not normally account for spatial attributes, except perhaps
for spatial identity of subpopulations.
Status
The distribution of scores for condition indicators with relation to
the reference condition associated with specific social values or
desired uses for a specific time period.
Stratum (strata)
A sampling structure that restricts sample randomization/selection
to a subset of the frame. Inclusion probabilities may or may not
differ among strata.
Stressor
“Any physical, chemical, or biological entity that can induce an
adverse response.”
Stressor indicator
A characteristic of the environment that is suspected to elicit a
change in the state of an ecological resource, and they include
both natural and human-induced stressors. Selected stressor indicators will be monitored in EMAP only when a relationship between
specific condition and stressor indicators is known or if a testable
hypothesis can be formulated.
Subnominal
Having undesirable or unacceptable ecological condition. The
quantified standard established for a condition indicator to represent
unacceptable or undesirable ecological condition is called the
subnominal assessment endpoint.
Subpopulation
Any subset of a population, usually having a specific attribute that
distinguishes its members from the rest of the population, for
example, lakes from a specified population that are above 1000 m
in elevation. Subpopulations are important entities in the EMAP
plan. Any defined subpopulation is subject to characterization via
estimation of subpopulation attributes and comparison to other
subpopulations. It is this focus that imposes the greatest restrictions
on the EMAP design and establishes the primary directions of the
EMAP analyses.
Surface fitting
A statistical procedure of estimating the parameters of a surface
model or of approximating an implied surface by distribution free
methods from a spatially distributed sample. A two-dimensional
generalization of regression.
Surface waters
The inland surface waters consisting of all the nation’s lakes (other
than the Great Lakes), rivers, and streams. Lakes are distinguished
from wetlands by depth and by size. Streams (and rivers) will be
identified from stream traces on maps and confirmed in field visits.
5 Geographic Information Systems and Remote Sensing Applications in Environmental. . . 231
artificial units constructed for the sole purpose of the sampling
design.
Science Advisory Board
(SAB)
A peer review panel internal to USEPA. The Ecological Effects
Committee of the SAB conducts reviews of EMAP’s overall program and the conceptual framework for integrating EMAP with
ORD’s Ecological Risk Assessment program. Preparation for SAB
reviews is coordinated by the director of the Office of Modeling,
Monitoring Systems, and Quality Assurance (OMMSQA); the
assistant administrator for ORD is responsible for funding. SAB
review is considered level 1 peer review.
Spatial model
A set of rules and procedures for conducting spatial analysis to
derive new information that can be analyzed to aid in problem
solving and planning.
Spatial statistics
Statistical methodology and theory that accounts for spatial aspects
of a spatially distributed dataset. Conventional population estimation does not normally account for spatial attributes, except perhaps
for spatial identity of subpopulations.
Status
The distribution of scores for condition indicators with relation to
the reference condition associated with specific social values or
desired uses for a specific time period.
Stratum (strata)
A sampling structure that restricts sample randomization/selection
to a subset of the frame. Inclusion probabilities may or may not
differ among strata.
Stressor
“Any physical, chemical, or biological entity that can induce an
adverse response.”
Stressor indicator
A characteristic of the environment that is suspected to elicit a
change in the state of an ecological resource, and they include
both natural and human-induced stressors. Selected stressor indicators will be monitored in EMAP only when a relationship between
specific condition and stressor indicators is known or if a testable
hypothesis can be formulated.
Subnominal
Having undesirable or unacceptable ecological condition. The
quantified standard established for a condition indicator to represent
unacceptable or undesirable ecological condition is called the
subnominal assessment endpoint.
Subpopulation
Any subset of a population, usually having a specific attribute that
distinguishes its members from the rest of the population, for
example, lakes from a specified population that are above 1000 m
in elevation. Subpopulations are important entities in the EMAP
plan. Any defined subpopulation is subject to characterization via
estimation of subpopulation attributes and comparison to other
subpopulations. It is this focus that imposes the greatest restrictions
on the EMAP design and establishes the primary directions of the
EMAP analyses.
Surface fitting
A statistical procedure of estimating the parameters of a surface
model or of approximating an implied surface by distribution free
methods from a spatially distributed sample. A two-dimensional
generalization of regression.
Surface waters
The inland surface waters consisting of all the nation’s lakes (other
than the Great Lakes), rivers, and streams. Lakes are distinguished
from wetlands by depth and by size. Streams (and rivers) will be
identified from stream traces on maps and confirmed in field visits.
5 Geographic Information Systems and Remote Sensing Applications in Environmental. . . 231