Soundscape and Landscape Ecology - Soundscape Ecology: Principles, Patterns, Methods and Applications - page 22

1.12 The Sonic Components of the Environment
and the General Theory of Resources
The word resource is used in both ecology and economics, and literally it means
“re-surge,” from the Latin “spring (surgere) again (re).” This term can be applied to
every natural element (abiotic and biotic) as well as to any manmade elements,
material or immaterial, which, after having been used/consumed, regenerates itself
by way of its internal, independent mechanisms. Some sounds (especially music) or
some sonotopes such as the bird chorus in an urban park, or the silence of a remote
location in the wild, can be considered acoustic resources.
According to his “general theory of resources” (Farina 2012 ), the individual
sounds, sonotopes, and soundtopes may be considered resources for a receiver when
these objects are requested to satisfy a need. For instance, in territorial defense a song
from a competitor represents a ranging resource to establish the less costly behavior in
territory maintenance. A soundtope of a roosting flock of starlings ( Sturnus vulgaris )
represents information on the location of abundant food for eavesdropping
individuals. A sonotope created by sea waves against a coral reef represents
the location where the pelagic larvae of reef fish move (Tolimieri et al. 2000 ).
1.13 Definition of a Sonic Eco-Field
Sonic processes refer to the dynamics and the effects that sounds produce on living
organisms such as reverberation, masking, annoyance, stress, mating selection, and
phonotaxy. The sonic processes are subjectively perceived and as a consequence
they always require a focal species or aggregation (population, community) to be
identified. Some important sonic processes activated for mating, for territory
defense, or for antipredatory strategies are explained when the eco-field theory is
adopted.
This theory states that to locate resources every organism requires the presence
of an eco-field, defined as a spatial configuration carrier of meaning for a specific
function (Farina and Belgrano 2004 , 2006 ).
According to a biosemiotic Percian model ( object, interpretant, representamen ),
the eco-field is the representamen where the object is the resource whereas the
interpretant is the function (Farina 2008 ) (Fig. 1.13 ).
The eco-field is recognized by a cognitive template activated by a specific
function when a physiological need for a specific resource exceeds a certain
threshold.
The eco-field can be represented by a spatial arrangement of fixed objects such
as trees, mobile animals such as herds, or sonic energy. In this last case we prefer to
name this specific eco-field a sonic eco-field. The spatial distribution of broadcast
sonic signals is used to locate specific resources.