Exploring the relationship between the soundscape and the environment: A systematic review

Abstract

The soundscape encompasses all biological, geophysical, and anthropogenic sounds in an environment and serves as an important communication medium for biota. While macro-level observations have suggested a correlation between the acoustic and physical environments, detailed and synthesized empirical evidence establishing nuanced relationships remains limited. Establishing empirical relationships between the soundscape and the environment is essential to ensure monitoring programs are grounded in robust ecological principles. However, empirical evidence about the relationship between the soundscape, environmental attributes, and biotic communities is scarce and scattered. Here, we synthesize evidence about correlations between the soundscape and at least one environmental variable or indicator. We analyse where (location) and when (year) the relationships between the soundscape and the environment have been investigated, what study designs and methods have been used to quantify these relationships, and what relationships were found between the soundscape and environmental or biological attributes. Our key findings include (1) the relationship between the soundscape and the environment is underexplored in aquatic ecosystems – particularly freshwater; (2) riparian and underwater soundscapes are seldom monitored simultaneously; and (3) the relationships found are not tested across various climate regions, elevations, temporal and spatial scales, or study designs. Since most studies use acoustic indices to analyse their soundscape, future research needs to assess whether the relationships between the soundscape and the environment change under different audio processing methods. We also show there is potential to extend the likes of acoustic monitoring far beyond monitoring soniferous biota populations, to include monitoring ecological health, ecosystem processes, and non-soniferous biota. Finally, we present a list of key questions to increase our knowledge of the connection between the soundscape and the environment. These questions will promote a solid conceptual base for future acoustic monitoring programs that enhance the interpretation of acoustic data, develop new technologies, and consider a broader cross-system (land to water) context.

Keywords

• Ecoacoustics
• Soundscape ecology
• Biodiversity monitoring
• Environmental ecology
• Ecological monitoring
• Remote monitoring