Perspectives on the Ecological Role of Geophysical Sounds

Abstract

Humans categorize unwanted sounds in the environment as noise. Consequently, noise is associated with negative human and ecological values, especially when it is derived from an anthropogenic source. Although evidence confirms that many machine-generated anthropogenic sounds have negative impacts on animal behavior and communication, natural sources of non-biological sound, such as wind, rain, running water, and sea waves (geophonies) have also been categorized as noise and are frequently dismissed or mischaracterized in acoustic studies as an outside factor of acoustic habitats rather than an integrated sonic component of ecological processes and species adaptations. While the proliferation of machine-generated sound in the Biosphere has become an intrusive phenomenon in recent history, geophony has shaped the Earth’s sonic landscapes for billions of years. Therefore, geophonies have very important sonic implications to the evolution and adaptation of soniferous species, forming essential ecological and semiotical relationships. This creates a need to distinguish geophonies from machine-generated sounds and how species respond to each accordingly, especially given their acoustic similarities in the frequency spectrum. Here, we introduce concepts and terminology that address these differences in the context of ecoacoustics. We also discuss how Acoustic Complexity Indices (ACIs) can offer new possibilities to quantifiably evaluate geophony in relation to their sonic contest.

Sonotope patterns within a mountain beech forest of Northern Italy: a methodological and empirical approach

“…July-August Tot ≤2000 >2000 Tot ≤2000 >2000 astronomical periods. The sources of low-frequency sonic events are commonly attributed to geophony produced by wind when in rural and remote areas (Mullet et al, 2016;Farina et al, 2021b). Although mid-to high-frequency sounds >2000 Hz, associated with biophony (Gage and Axel, 2014;Farina and James, 2016), were more subtle than low-frequency geophonies, biophony throughout our study area was more prevalent in July-August, when the breeding season of birds was at the end, than in May-June.…”

Soundscape mapping: understanding regional spatial and temporal patterns of soundscapes incorporating remotely-sensed predictors and wildfire disturbance

“…The decreased quiet, during increased anthropophony and at times of increased biophony, describes silences and not a naturally quiet landscape. Comparatively, naturally-quiet landscapes contain biophony and geophony and are valued for human enjoyment (Farina et al 2021). Quiet, here, helps identify acoustically active landscapes and avoid less ecologically relevant spaces, especially for future soundscape analysis.…”

Human Auditory Ecology: Extending Hearing Research to the Perception of Natural Soundscapes by Humans in Rapidly Changing Environments

“…Geophony (wind, rain, stream sounds, etc.) is assumed to play an active role in ecological processes, including habitat selection (Doligez & Boulinier, 2008; Farina et al, 2021; Mullet et al, 2017), that is “the act of choosing the combination of available abiotic and biotic elements for the purpose of fulfilling the life history events of the organism” (Montgomery & Roloff, 2017). Water may have a special status in that respect, not only because of its acoustic characteristics (Geffen et al, 2011; Guyot et al, 2017; McDermott et al, 2009), but also because of its vital importance to living organisms as an essential nutrient.…”