Geoscience Reference
In-Depth Information
5
CHAPTER
Light Attenuation Profiling as an Indicator of
Structural Changes in Coastal Marshes
Elijah Ramsey III, Gene Nelson, Frank Baarnes, and Ruth Spell
CONTENTS
5.1 Introduction.............................................................................................................................59
5.1.1 Marsh Canopy Descriptions .......................................................................................60
5.2 Methods ..................................................................................................................................61
5.2.1 Field Collection Methods ...........................................................................................61
5.2.1.1 Area Frequency Sampling...........................................................................62
5.2.1.2 Vertical Frequency Sampling ......................................................................62
5.2.1.3 Atypical Canopy Structures ........................................................................62
5.2.1.4 Changing Sun Zenith ..................................................................................63
5.3 Results.....................................................................................................................................64
5.3.1 Vertical Frequency Sampling .....................................................................................64
5.3.2 Atypical Canopy Structures .......................................................................................65
5.3.3 Changing Sun Zenith..................................................................................................67
5.4 Discussion...............................................................................................................................69
5.5 Summary.................................................................................................................................71
Acknowledgments ............................................................................................................................72
References ........................................................................................................................................72
5.1 INTRODUCTION
To best respond to natural and human-induced stresses, resource managers and researchers
require remote sensing techniques that can map the biophysical characteristics of natural resources
on regional and local scales. The implementation of advanced measurement techniques would
provide significant improvements in the quantity, quality, and timeliness of biophysical data useful
in understanding the sensitivity of vegetation communities to external influences. In turn, this
biophysical data would provide resource planners with a rational decision-making system for
resource allocation and response action development planning.
Remotely sensed imagery can be analyzed to provide an accurate, instantaneous, synoptic view
of the spatial characteristics of vegetation environments (Ustin et al., 1991; Wickland, 1991). By
59
