TY - JOUR T1 - The quantitative relation between ambient soundscapes and landscape development intensity in North Central Florida JF - Landscape Ecology Y1 - 2019 A1 - Dooley, Jenet M. A1 - Brown, Mark T. KW - Ambient sound KW - Anthrophony KW - biophony KW - Development intensity KW - LDI index KW - Noise disturbance KW - Power spectral density KW - Remote sensing KW - Soundscape KW - Technophony AB -

Context

It is widely accepted that wildlife is subjected to detrimental human noise within urban landscapes but little is known about how the intensity of land use changes soundscapes.

Objectives

The objective of this research was to produce quantitative associations between characteristics of ambient soundscapes and land use intensity. These relations were used to examine the 2 kHz demarcation between anthrophony and biophony and compare the impact of different sized contributing areas on ambient soundscape characteristics.

Methods

This study related the surrounding land use intensity of 67 sites in north central Florida (USA) to several metrics describing their recorded soundscapes. Land use intensity was measured remotely at three scales using the landscape development intensity index (LDI).

Results

The analysis revealed that the LDI index had a statistically significant effect on soundscape characteristics after controlling for important factors such as climate, season, and attenuation due to hard ground. The trends between LDI and soundscape confirmed that human generated sounds are loud, continuous, and occupy low frequencies. The evenness of the sound distribution decreased with landscape intensity and LDI correlated significantly with sound below 3 kHz. Land use intensity within a 100 and 500-m radius contributing area were most closely related to soundscape metrics.

Conclusions

LDI is a tool with the potential to predict the extent and intensity of anthropogenic noise disturbance on wildlife from remote sensing data. The utility of this tool allows for widespread application to identify and mitigate conflicts in the acoustic realm between human noise and wildlife.

UR - http://link.springer.com/10.1007/s10980-019-00936-2 JO - Landscape Ecol ER - TY - THES T1 - ANALYSIS AND VISUALISATION OF VERY-LONG-DURATION ACOUSTIC RECORDINGS OF THE NATURAL ENVIRONMENT T2 - School of Electrical Engineering and Computer Science Y1 - 2018 A1 - Yvonne Phillips KW - acoustic indices KW - Anthropophony KW - bioacoustics KW - biophony KW - Cicadas KW - Clustering KW - Data reduction KW - Diel plots; Dot-matrix plots KW - ecoacoustics KW - Ecological Monitoring KW - Geophony KW - Long-duration false-colour spectrograms KW - Microphone malfunction KW - Principal Components Analysis KW - Soundscape ecology KW - Very-long-duration audio recording KW - Visualisation AB -

Advances in technology and reduction in data storage costs enable the autonomous collection of large quantities of continuous audio recordings. While the collection of very long environmental recordings has become easier, the analysis of these recordings remains challenging. A very-long-duration audio recording is defined as one with a minimum length of one day, but may have durations of weeks, months, or years. This thesis provides methods for data reduction and visualisation that enable the ecological interpretation and navigation of very-long-duration audio recordings.
The major theme of data reduction commenced after the establishment of protocols and the collection of two thirteen-month continuous audio recordings from two separate Southeast Queensland forest ecosystems. The acoustic indices calculated on one-minute audio segments were used to develop two new techniques to visualise the contents of very- long-duration recordings. An acoustic index is a mathematical expression used to measure a particular aspect of the energy distribution in audio recordings. Microphone failure in one channel was noticed shortly after the recording commenced. A method was established to detect microphone problems in long recordings.
A novel error measure was developed to detect seasonal and site differences and enable optimisation of the clustering based on seasonal and site differences in the data. Cluster interpretation on very-long-duration audio recordings is problematic because listening to large amounts of audio is time-consuming and therefore impractical. To overcome this, a series of five methods were developed to build on the interpretations made through listening. These methods enabled the allocation of an acoustic label to each cluster, resulting in a labelled acoustic sequence. This acoustic sequence was used to develop three additional visualisation techniques.
The culmination of the methods developed in this thesis was the six case studies. These extended the ecological interpretation of the acoustic sequence beyond those that were made through the visualisations. The case studies demonstrated that clustering can facilitate ecological interpretation of very-long-duration audio recordings.

JF - School of Electrical Engineering and Computer Science PB - Queensland University of Technology UR - https://eprints.qut.edu.au/123020/1/Yvonne_Phillips_Thesis.pdf ER - TY - JOUR T1 - Acoustic masking of soniferous species of the St-Lawrence lowlands JF - Landscape and Urban Planning Y1 - 2017 A1 - Desrochers, Louis A1 - Proulx, Raphaƫl KW - acoustic masking KW - biophony KW - distribution overlap KW - phenology KW - soundscapes KW - urban noise AB -

How much of the acoustic resource shared by vocalizing animal species is masked by human-induced noise has become a central question in the emerging field of soundscape ecology. The goal of our study was to evaluate the joint probability that masking could occur for anuran, bird, or stridulating orthopteran species along the spectral, spatial and temporal dimensions of the acoustic space. We evaluated acoustic overlap in the dominant frequencies, absolute amplitudes (emitter-receiver distances), and time-series (temporal match-mismatch) of human- and animal-induced sounds in three landscape settings: urban, peri-urban and rural. Acoustic overlap was evaluated at the day scale during the active vocalizing period of each taxon. Our results suggest that acoustic masking is unlikely for a vast majority of species in the three taxonomic groups; ranging from 5–7% for anurans to 3–4% for birds and less than 1% for orthopterans. However, in urban contexts, acoustic masking could be a selective force when coupled to other factors that covary with the amount of noise produced by human activities, such as habitat loss and degradation.

VL - 168 UR - http://linkinghub.elsevier.com/retrieve/pii/S0169204617302232 JO - Landscape and Urban Planning ER -