What is acoustic diversity? Definitions and examples

Acoustic diversity refers to the measurement of sound variation within a given environment across criteria such as frequency, quality, and temporal distribution.

Due to “the inherent informational value of sound within ecosystems”, investigating acoustic diversity can lead to significant conclusions, with research into bioacoustics and ecology allowing the relationship between biodiversity and sonic environments to become better understood. Monitoring acoustic diversity can be an effective method for evaluating biodiversity; for example, reductions in acoustic diversity can demonstrate biodiversity loss as a result of “a disruption of ecological processes”. 

In this way, the study of acoustic diversity has been part of an increased understanding of the importance of animal sounds to their communication, navigation, mating, and avoidance of predators, as well as how injurious the effects of anthropophony are upon wildlife – reducing its ability to use sounds for these purposes. The resulting fuller appreciation of the relationship between natural and human systems demonstrates the breadth of acoustic diversity’s relevance.

As it relates to biophony, the concept of acoustic diversity can act as a reminder that the diversity of the living natural world – biodiversity – is not solely confined to the “visual perspective” where difference is visualized through “size, shape or color”. On the contrary, biodiversity can be embodied sonically by acoustic diversity via the “sounds […] emanating intentionally or involuntarily from living organisms – birds, mammals, amphibians, insects, fish, plants and others”.

Soundscape analysis software (allowing acoustic data to be processed and visualized) and passive acoustic monitoring (PAM; which allows large-scale data collection across a range of environments) – “reliable and low-cost approach[es] to monitoring vocalizing biodiversity over extended periods” – are continuing to foster a holistic understanding of the importance of acoustic diversity, including the correlation between high acoustic diversity and high levels of biodiversity. In addition, “explor[ation] [of] the spatial and temporal patterns of soundscapes, [has] connect[ed] them to broader ecological processes”, countering the conception of soundscapes as discrete or insignificant. 

Alongside increasing acknowledgement of “the limitations of traditional environmental metrics” – methods which may not fully convey environmental health in all of its detail – acceptance of acoustic diversity’s importance has grown accordingly. In fact, it is increasingly accepted that “environmental sounds [can be used] to […] examine and interpret various dynamic ecological processes”. This has in part been driven by the repercussions of noise pollution on human mental and physical health. In terms of urban living, understanding the serious health problems which can arise from excessive anthropophonic noise means that introducing acoustic diversity via “natural elements […] such as green spaces and water features” can be of critical importance.

Acoustic diversity has therefore become vital not only for ecological health but for “the social and economic well-being of human populations”; as a result, the relevance of this topic extends beyond the environmental but also to social and economic fields.

As the data collection and analysis necessary for the study and understanding of acoustic diversity has not yet become standardized, it can, however, be difficult to “establish consistent metrics” for the discipline. Similarly, a lack of public understanding of this area of study means that securing its support for relevant “soundscape management and preservation” can be challenging. Nevertheless, studying acoustic diversity has important applications within environmental conservation, urban planning, and sustainable development.

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Featured photo by Mati Flo on Unsplash