Full metadata
Title
Quantifying percent-cover in Prescott National Forest, Arizona through the integration of Landsat imagery, vegetation Indices, and spatial transformations
Description
Accurate characterization of forest canopy cover from satellite imagery hinges on the development of a model that considers the level of detail achieved by field methods. With the improved precision of both optical sensors and various spatial techniques, models built to extract forest structure attributes have become increasingly robust, yet many still fail to address some of the most important characteristics of a forest stand's intricate make-up. The objective of this study, therefore, was to address canopy cover from the ground, up. To assess canopy cover in the field, a vertical densitometer was used to acquire a total of 2,160 percent-cover readings from 30 randomly located triangular plots within a 6.94 km2 study area in the central highlands of the Bradshaw Ranger District, Prescott National Forest, Arizona. Categorized by species with the largest overall percentage of cover observations (Pinus ponderosa, Populus tremuloides, and Quercus gambelii), three datasets were created to assess the predictability of coniferous, deciduous, and mixed (coniferous and deciduous) canopies. Landsat-TM 5 imagery was processed using six spectral enhancement algorithms (PCA, TCT, NDVI, EVI, RVI, SAVI) and three local windows (3x3, 5x5, 7x7) to extract and assess the various ways in which these data were expressed in the imagery, and from those expressions, develop a model that predicted percent-cover for the entire study area. Generally, modeled cover estimates exceeded actual cover, over predicting percent-cover by a margin of 9-13%. Models predicted percent-cover more accurately when treated with a 3x3 local window than those treated with 5x5 and 7x7 local windows. In addition, the performance of models defined by the principal components of three vegetation indices (NDVI, EVI, RVI) were superior to those defined by the principal components of all four (NDVI, EVI, RVI, SAVI), as well as the principal and tasseled cap components of all multispectral bands (bands 123457). Models designed to predict mixed and coniferous percent-cover were more accurate than deciduous models.
Date Created
2012
Contributors
- Schirmang, Tracy Lynn (Author)
- Myint, Soe W (Thesis advisor)
- Fall, Patricia L. (Thesis advisor)
- Brazel, Anthony J. (Committee member)
- Arizona State University (Publisher)
Topical Subject
Resource Type
Extent
vi, 43 p. : ill. (some col.), maps (some col.)
Language
eng
Copyright Statement
In Copyright
Primary Member of
Peer-reviewed
No
Open Access
No
Handle
https://hdl.handle.net/2286/R.I.14983
Statement of Responsibility
by Tracy Lynn Schirmang
Description Source
Retrieved on May 1, 2013
Level of coding
full
Note
thesis
Partial requirement for: M.A., Arizona State University, 2012
bibliography
Includes bibliographical references (p. 42-43)
Field of study: Geography
System Created
- 2012-08-24 06:27:33
System Modified
- 2021-08-30 01:46:16
- 3 years 2 months ago
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