The closely related split-beam echo sounders can provide another layer for habitat
interpretation by quantifying the size and density of fishes.
9.2 Applications
The principle of optical discrimination (i.e., photography, multispectral and
hyperspectral) is generally intuitive at a fundamental level, relating directly to the
spectral properties of the benthos. Although acoustic discrimination is not so
straightforward, rapid progress is currently being made in creating benthic habitat
maps from acoustic data. In the field of ASC mapping, recent advances in interpreting acoustic backscatter have led to benthic habitat maps with greater thematic
accuracy and resolution. In the fields of SSS and MBES mapping, application of
tonal and textural classifiers to backscatter imagery have greatly expanded the
output of these systems to include a rapidly expanding suite of seafloor properties.
Examples of such applications are presented below.
9.2.1 Single-Beam Acoustic Seabed Classification
Mumby and Harborne (1999) argued that a standardized approach to mapping
tropical coastal habitats greatly increased the utility of the resulting maps. Greene
et al. (1999) made the same argument for deep seabed habitats. Anderson et al.
(2008) proposed a list of ten priorities for research that would advance the field of
acoustic seabed classification. At least five of these priority research areas fall
under the general topic of standardizing instruments and methods. There is
widespread agreement, therefore, on the benefits of standardization, but almost no
studies employing single-beam ASC in coral reef study sites have used the same
classification scheme (Table 9.1).
Developing a standardized approach to mapping relies on an objective and
systematic method for defining seabed classes; it does not require producing every
habitat map at the same spatial scale, thematic resolution, or using the same data
source (Mumby and Harborne 1999). Hierarchical classification schemes are one
way to provide both commonality among sites and flexibility to identify detailed
classes where needed. The span of thematic and spatial resolutions required for
these tasks also dictates a hierarchical classification scheme that can be expanded
or collapsed to the desired level of detail or resolution of available data (Mumby
and Harborne 1999). Examples of hierarchical classification schemes include those
developed by the Florida Marine Research Institute (Madley et al. 2002) and the
NOAA Biogeography Branch (Costa et al. 2009a).
This section describes two recent developments that advance single-beam ASC
toward the goal of employing a hierarchical classification scheme based on
geomorphology and biotic cover that would be applicable to multiple sites and
9 Acoustic Applications
227
interpretation by quantifying the size and density of fishes.
9.2 Applications
The principle of optical discrimination (i.e., photography, multispectral and
hyperspectral) is generally intuitive at a fundamental level, relating directly to the
spectral properties of the benthos. Although acoustic discrimination is not so
straightforward, rapid progress is currently being made in creating benthic habitat
maps from acoustic data. In the field of ASC mapping, recent advances in interpreting acoustic backscatter have led to benthic habitat maps with greater thematic
accuracy and resolution. In the fields of SSS and MBES mapping, application of
tonal and textural classifiers to backscatter imagery have greatly expanded the
output of these systems to include a rapidly expanding suite of seafloor properties.
Examples of such applications are presented below.
9.2.1 Single-Beam Acoustic Seabed Classification
Mumby and Harborne (1999) argued that a standardized approach to mapping
tropical coastal habitats greatly increased the utility of the resulting maps. Greene
et al. (1999) made the same argument for deep seabed habitats. Anderson et al.
(2008) proposed a list of ten priorities for research that would advance the field of
acoustic seabed classification. At least five of these priority research areas fall
under the general topic of standardizing instruments and methods. There is
widespread agreement, therefore, on the benefits of standardization, but almost no
studies employing single-beam ASC in coral reef study sites have used the same
classification scheme (Table 9.1).
Developing a standardized approach to mapping relies on an objective and
systematic method for defining seabed classes; it does not require producing every
habitat map at the same spatial scale, thematic resolution, or using the same data
source (Mumby and Harborne 1999). Hierarchical classification schemes are one
way to provide both commonality among sites and flexibility to identify detailed
classes where needed. The span of thematic and spatial resolutions required for
these tasks also dictates a hierarchical classification scheme that can be expanded
or collapsed to the desired level of detail or resolution of available data (Mumby
and Harborne 1999). Examples of hierarchical classification schemes include those
developed by the Florida Marine Research Institute (Madley et al. 2002) and the
NOAA Biogeography Branch (Costa et al. 2009a).
This section describes two recent developments that advance single-beam ASC
toward the goal of employing a hierarchical classification scheme based on
geomorphology and biotic cover that would be applicable to multiple sites and
9 Acoustic Applications
227