Soundscape and Landscape Ecology - Soundscape Ecology: Principles, Patterns, Methods and Applications - page 11

Fig. 1.4 In the soundscape,
geophonies are the sonic
sources that have a
direct influence on
biophonies and secondarily
on anthrophonies.
Anthrophonies can strongly
impact on biophonies
1.6.4 The Relatioships Between Geophonies, Biophonies
and Anthrophonies
The interaction between geophonies, biophonies, and anthrophonies determines
peculiar patterns in the sonic environment. The geophonies represent the indepen-
dent variable when compared with the other two sources; its influence is the main
constraint especially affecting the biophonies (Fig. 1.4 ).
It is demonstrated that high levels of geophonies or anthrophonies depress the
biophonies or modify the way in which organisms emit sounds (songs, calls, alarms,
vocalizations).
For instance, a windy day depresses the song of most birds, and proximity to a
heavily traveled highway prevents acoustic communication among the majority of
vocal species living in the neighborhoods. Figure 1.5 shows a map of a soundscape
created plotting recording sessions with sampling stations.
The depression in soundscape activity that is observable on the right side of the
picture is coincident with the presence of a small river, whose noise masks or
depresses the biophonies (mainly produced by birds).
Climatic events are important constraint for biophonies. The anthrophonies can
produce severe changes in biophonies when these are of strong intensity, as close to
an airport. Anthrophonies (ship engines, drilling platforms) have dramatic effects in
both shallow and deep waters, affecting the survival of whales and other cetaceans.
In urban areas, the presence of vegetation in parks and along the avenues reduces
the effect of traffic noise and noise in general, as well documented by Voichita
Bucur in the 2006 topic Urban Forest Acoustic (Bucur 2006 ).
1.7 Foreground and Background Sonic Environment
Sonic events have qualitative (e.g., frequency categories) and quantitative (e.g.,
pressure level) characteristics. The spatial and temporal variations of these
characteristics create a dynamic sonic gradient across the landscapes, providing
additional information not otherwise available.
In fact, the addition of sonic variables to a landscape analysis allows us to
consider the temporal variability of the landscape.