Vegetation Classification and Mapping Project Report - USGS

Vegetation Classification and Distribution Mapping Report: Petrified Forest National Park
Transition zone: An area where the
vegetation composition and structure is
intermediate between two associations.
The transition zone may be small as the
associations abruptly change due to a large
shift in the landscape, such as a cliff, or it
may be large as the physical environment
changes gradually. Transition zones often
are challenges to properly classify and/or
map vegetation.
United States National Map Accuracy
Standards (NMAS): USGS accuracy
standards for published maps, including
horizontal and vertical accuracy, accuracy
testing method, accuracy labeling on
published maps, labeling when a map is
an enlargement of another map, and basic
information for map construction as to
latitude and longitude boundaries. The
table below shows the standard for some
common map scales. To meet NMAS
maps must have less than 10 percent of the
points tested (well-defined points) exceed
the standard. Note that the conversion of
paper maps into digital data usually creates
additional error.
sample from the mapped data actually
represents that category on the ground,
also known as error of commission. This
quantity is computed by dividing the
number of correctly classified samples
by the total number of samples that were
classified as belonging to that category
(Story and Congalton 1986). Compare with
producer accuracy.
Universal Transverse Mercator
(UTM): Map coordinate system (not a
map projection) that is defined by the
Transverse Mercator projection, which has
a set of zones defined by a central meridian
as shown in the figure below for the United
States (Portions from ESRI 1994). All
spatial data products developed by the
program (vegetation spatial data, plot and
accuracy assessment plot data locations
are in this coordinate system.
68
Horizontal accuracy examples.
Scale Engineering National Map
Scale Accuracy
Standard
1:1,200 1”= 100’ +/- 3.33 feet
1:2,400 1”= 200’ +/- 6.67 feet
1:4,800 1”= 400’ +/- 13.33 feet
1:9,600 1”= 800’ +/- 26.67 feet
1:10,000 +/- 27.78 feet
1:12,000 1” = 1000’ +/- 33.33 feet
1:24,000 1” = 2000’ +/- 40.00 feet
1:63,360 1” = one mile +/- 105.60 feet
1:100,000 +/- 166.67 feet
United States National Vegetation
Classification (USNVC): The Association
for Biodiversity’s vegetation classification
system. It is the basis for the FGDC
National Vegetation Classification
Standard.
User accuracy: The probability that a
Universal Transverse Mercator projections for
the U.S.
Vegetation: The collective plant cover over
an area (FGDC 1997).
Vegetation characterization: The detailed
portrayal of a vegetation association
using diagnostic and dominant species,
structure, and ecological processes.
The program has a formal structure for
association description based on the
ABI model. Also known as vegetation
description. An example of an association
characterization can be found at http://
biology.usgs.gov/npsveg/agfo/mapclass/
scbc.pdf.
Vegetation classification: The process
of categorizing vegetation into repeatable