scholarly journals Advancing the Interpretation of Shallow Water Marine Soundscapes

2021 ◽  
Vol 8 ◽  
Author(s):  
Megan F. McKenna ◽  
Simone Baumann-Pickering ◽  
Annebelle C. M. Kok ◽  
William K. Oestreich ◽  
Jeffrey D. Adams ◽  
...  
Keyword(s):  
Shallow Water ◽  
Human Activity ◽  
Tidal Flow ◽  
Integrated Approach ◽  
Sound Level ◽  
Sound Levels ◽  
Tidal Changes ◽  
Human Use ◽  
Using Data ◽  
Acoustic Environments

Soundscapes offer rich descriptions of composite acoustic environments. Characterizing marine soundscapes simply through sound levels results in incomplete descriptions, limits the understanding of unique features, and impedes meaningful comparisons. Sources that contribute to sound level metrics shift in time and space with changes in biological patterns, physical forces, and human activity. The presence of a constant or chronic source is often interwoven with episodic sounds. Further, the presence and intensity of sources can influence other sources, calling for a more integrated approach to characterizing soundscapes. Here, we illustrate this complexity using data from a national-scale effort, the Sanctuary Soundscape Monitoring Project (SanctSound), an initiative designed to support collection of biological, environmental, and human use data to compliment the interpretation of sound level measurements. Using nine examples from this diverse dataset we demonstrate the benefit of integrating source identification and site features to interpret sound levels across a diversity of shallow water marine soundscapes (<150 m). Sound levels from sites in high human use areas reflect the anthropogenic influences on the soundscape, especially when measuring broad frequency bands, whereas sites with relatively low human activity and high sound levels reveal biological features of the soundscape. At sites with large tidal changes, sound levels correlated with the magnitude of tidal flow, and sound levels during high tidal flow periods were similar to sound levels at sites near commercial shipping lanes. At sites in relatively close proximity (<30 km), sound levels diverge because of the presence of different proximate sound contributors and propagation features of the site. A review of emerging methodologies for integrated soundscape analysis, including acoustic scenes, provides a framework for interpreting soundscapes across a variety of conditions. With a global growth in monitoring efforts collecting standardized measurements over widely distributed arrays, more integrated methods are needed to advance the utility of soundscapes in marine resource management.

scholarly journals How Wildlife Respond to Natural Noise

2021 ◽  
Author(s):  
Dylan G.E. Gomes
Keyword(s):  
Sound Level ◽  
Anthropogenic Sources ◽  
Anthropogenic Noise ◽  
Frequency Noise ◽  
Spider Webs ◽  
Predator Prey ◽  
Sound Levels ◽  
Natural Noise ◽  
Acoustic Environments ◽  
High Sound

Animal sensory systems have evolved in a natural din of noise since the evolution of sensory organs. Anthropogenic noise is a recent addition to the environment, which has had demonstrable, largely negative, effects on wildlife. Yet, we know relatively little about how animals respond to natural sources of noise, which can differ substantially in acoustic characteristics from human-caused noise. Here we review the noise literature and suggest an evolutionary approach for framing the study of novel, anthropogenic sources of noise. We also push for a more quantitative approach to acoustic ecology research. To build a better foundation around the effects of natural noise on wildlife, we experimentally and continuously broadcast whitewater river noise across a landscape for three summers. Additionally, we use spectrally-altered river noise to explicitly test the effects of masking as a mechanism driving patterns. We then monitored bird, bat, and arthropod abundance and activity and assessed predator-prey relationships with bird and bat foraging assays and by counting prey in spider webs. Birds and bats largely avoided high sound levels in noisy environments. Bats also avoided acoustic environments dominated by high frequency noise while birds avoided noise that overlapped with their song, the latter trend suggesting that communication is impaired. Yet, when sound levels were high overlapping noise was not any more disruptive than non-overlapping noise, which suggests that intense noise interferes with more than communication. Avoidance of noise that overlapped in frequency with song was stronger for low-frequency singers. Bats that employ higher frequency echolocation were more likely to avoid high sound level noise; we explore potential explanations for this pattern. Most arthropod Orders responded to noise, yet the directions of effects were not consistent across taxa. Some arthropods increased in abundance in high sound level areas - perhaps in response to the absence of bird and bat predators. Reinforcing this possibility, visually foraging birds and passively listening bats decreased foraging effort beyond what was expected based on declines in abundance and activity. Orb-weaving spiders increased dramatically in high sound level areas, which could be due to a release from predation, an increase in prey capture, or direct attraction to high sound level river noise. Overall, we demonstrated significant changes to many vertebrate and invertebrate taxa during playback of whitewater river noise. We were able to parse out the effects of sound pressure level and background frequency on these individual taxa and predator-prey behaviors. Our results reveal that animals have likely long been affected by particular characteristics of noise, which may help explain contemporary responses to anthropogenic noise. As the spatial and temporal footprint of anthropogenic noise is orders of magnitude greater than intense natural acoustic environments, the insights provided by our data increase the importance of mitigating noise pollution impacts on animals and their habitats. It is clear that natural noise has the power to alter animal abundances and behavior in a way that likely reverberates through entire communities and food webs. Future work should focus on strengthening the relationships between these potential predators and prey and highlight how the structure of the system changes under such noise treatments.

scholarly journals Phantom rivers filter birds and bats by acoustic niche

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
D. G. E. Gomes ◽  
C. A. Toth ◽  
H. J. Cole ◽  
C. D. Francis ◽  
J. R. Barber
Keyword(s):  
Insect Wing ◽  
Passive Listening ◽  
Hunting Strategies ◽  
Sound Levels ◽  
Acoustic Niche ◽  
Using Data ◽  
Acoustic Environments ◽  
Breeding Seasons ◽  
And Behavior ◽  
High Sound

AbstractNatural sensory environments, despite strong potential for structuring systems, have been neglected in ecological theory. Here, we test the hypothesis that intense natural acoustic environments shape animal distributions and behavior by broadcasting whitewater river noise in montane riparian zones for two summers. Additionally, we use spectrally-altered river noise to explicitly test the effects of masking as a mechanism driving patterns. Using data from abundance and activity surveys across 60 locations, over two full breeding seasons, we find that both birds and bats avoid areas with high sound levels, while birds avoid frequencies that overlap with birdsong, and bats avoid higher frequencies more generally. We place 720 clay caterpillars in willows, and find that intense sound levels decrease foraging behavior in birds. For bats, we deploy foraging tests across 144 nights, consisting of robotic insect-wing mimics, and speakers broadcasting bat prey sounds, and find that bats appear to switch hunting strategies from passive listening to aerial hawking as sound levels increase. Natural acoustic environments are an underappreciated niche axis, a conclusion that serves to escalate the urgency of mitigating human-created noise.

scholarly journals The Spatial Selective Auditory Attention of Cochlear Implant Users in Different Conversational Sound Levels

2021 ◽  
Vol 10 (14) ◽  
pp. 3078
Author(s):  
Sara Akbarzadeh ◽  
Sungmin Lee ◽  
Chin-Tuan Tan
Keyword(s):  
Cochlear Implant ◽  
Sound Level ◽  
Auditory Attention ◽  
Impaired Hearing ◽  
Speech Stimuli ◽  
Electric Hearing ◽  
Sound Levels ◽  
Acoustic Hearing ◽  
Speech Envelope ◽  
Different Levels

In multi-speaker environments, cochlear implant (CI) users may attend to a target sound source in a different manner from normal hearing (NH) individuals during a conversation. This study attempted to investigate the effect of conversational sound levels on the mechanisms adopted by CI and NH listeners in selective auditory attention and how it affects their daily conversation. Nine CI users (five bilateral, three unilateral, and one bimodal) and eight NH listeners participated in this study. The behavioral speech recognition scores were collected using a matrix sentences test, and neural tracking to speech envelope was recorded using electroencephalography (EEG). Speech stimuli were presented at three different levels (75, 65, and 55 dB SPL) in the presence of two maskers from three spatially separated speakers. Different combinations of assisted/impaired hearing modes were evaluated for CI users, and the outcomes were analyzed in three categories: electric hearing only, acoustic hearing only, and electric + acoustic hearing. Our results showed that increasing the conversational sound level degraded the selective auditory attention in electrical hearing. On the other hand, increasing the sound level improved the selective auditory attention for the acoustic hearing group. In the NH listeners, however, increasing the sound level did not cause a significant change in the auditory attention. Our result implies that the effect of the sound level on selective auditory attention varies depending on the hearing modes, and the loudness control is necessary for the ease of attending to the conversation by CI users.

scholarly journals Impact of sound levels and patient-related factors on sleep of patients in the intensive care unit: a cross-sectional cohort study

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Piotr F. Czempik ◽  
Agnieszka Jarosińska ◽  
Krystyna Machlowska ◽  
Michał P. Pluta
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Sleep Quality ◽  
Sleep Duration ◽  
Smartphone Application ◽  
Sound Level ◽  
Related Factors ◽  
Cross Sectional ◽  
Sound Levels ◽  
The Impact

Abstract Sleep disruption is common in patients in the intensive care unit (ICU). The aim of the study was to measure sound levels during sleep-protected time in the ICU, determine sources of sound, assess the impact of sound levels and patient-related factors on duration and quality of patients' sleep. The study was performed between 2018 and 2019. A commercially available smartphone application was used to measure ambient sound levels. Sleep duration was measured using the Patient's Sleep Behaviour Observational Tool. Sleep quality was assessed using the Richards-Campbell Sleep Questionnaire (RCSQ). The study population comprised 18 (58%) men and 13 (42%) women. There were numerous sources of sound. The median duration of sleep was 5 (IQR 3.5–5.7) hours. The median score on the RCSQ was 49 (IQR 28–71) out of 100 points. Sound levels were negatively correlated with sleep duration. The cut-off peak sound level, above which sleep duration was shorter than mean sleep duration in the cohort, was 57.9 dB. Simple smartphone applications can be useful to estimate sound levels in the ICU. There are numerous sources of sound in the ICU. Individual units should identify and eliminate their own sources of sound. Sources of sound producing peak sound levels above 57.9 dB may lead to shorter sleep and should be eliminated from the ICU environment. The sound levels had no effect on sleep quality.

Tidal fish connectivity of reef and sea grass habitats in the Indo-Pacific

2007 ◽  
Vol 87 (5) ◽  
pp. 1287-1296 ◽  
Author(s):  
Richard K.F. Unsworth ◽  
James J. Bell ◽  
David J. Smith
Keyword(s):  
Shallow Water ◽  
National Park ◽  
Fish Assemblages ◽  
Fish Fauna ◽  
Subsistence Fisheries ◽  
Tidal State ◽  
Sea Grass ◽  
Water Fish ◽  
Tidal Changes ◽  
Near Shore

The present study considered the influence of the tide on shallow water fish assemblages within the Wakatobi Marine National Park, Indonesia. Timed underwater visual observations were made across a gradient of intertidal to subtidal habitats from near-shore to reef crest at different tidal heights. Transient fish were found to dominate shallow water fish assemblages and the assemblage composition varied with tidal state. Fish assemblages were more diverse and abundant at higher tides in both coral and sea grass habitats, however, this was more pronounced within sea grass habitats. A tidal reduction from ≈2.0m to ≈0.8m (above chart datum) corresponded to a 30% reduction in fish abundance, while species richness also significantly decreased from 13.5 to 10.8 species per standardized timed observation. Fifty fish groups were reported from sea grass habitats with the most abundant being from the Engraulidae family and Lethrinus harak, which form important local subsistence fisheries. This research confirms the importance of tidal changes in structuring the fish fauna of Indonesian sea grass habitats and underlines the connectivity that exists between these habitats and nearby coral reefs.

Incubator Noise

PEDIATRICS ◽  
1975 ◽  
Vol 56 (4) ◽  
pp. 617-617
Author(s):  
Gōsta Blennow ◽  
Nils W. Svenningsen ◽  
Bengt Almquist
Keyword(s):  
Low Frequency ◽  
Sound Level ◽  
Noise Levels ◽  
Frequency Sound ◽  
Mechanical Noise ◽  
Sound Levels ◽  
Infant Incubator ◽  
Improved Model ◽  
Model C

Recently we reported results from studies of incubator noise levels.1 It was found that in certain types of incubators the noise was considerable, and attention was called to the sound level in the construction of new incubators. Recently we had the opportunity to study an improved model of Isolette Infant Incubator Model C-86 where the mechanical noise from the electrically powered motor has been partially eliminated. With this modification it has been possible to lower the low-frequency sound levels to a certain degree in comparison to the levels registered in our study.

scholarly journals L-type calcium channels refine the neural population code of sound level

2016 ◽  
Vol 116 (6) ◽  
pp. 2550-2563 ◽  
Author(s):  
Calum Alex Grimsley ◽  
David Brian Green ◽  
Shobhana Sivaramakrishnan
Keyword(s):  
Calcium Channels ◽  
Calcium Current ◽  
Dynamic Range ◽  
Sound Level ◽  
Neural Population ◽  
Total Calcium ◽  
Local Networks ◽  
Sound Levels ◽  
Local Circuits

The coding of sound level by ensembles of neurons improves the accuracy with which listeners identify how loud a sound is. In the auditory system, the rate at which neurons fire in response to changes in sound level is shaped by local networks. Voltage-gated conductances alter local output by regulating neuronal firing, but their role in modulating responses to sound level is unclear. We tested the effects of L-type calcium channels (CaL: CaV1.1–1.4) on sound-level coding in the central nucleus of the inferior colliculus (ICC) in the auditory midbrain. We characterized the contribution of CaL to the total calcium current in brain slices and then examined its effects on rate-level functions (RLFs) in vivo using single-unit recordings in awake mice. CaL is a high-threshold current and comprises ∼50% of the total calcium current in ICC neurons. In vivo, CaL activates at sound levels that evoke high firing rates. In RLFs that increase monotonically with sound level, CaL boosts spike rates at high sound levels and increases the maximum firing rate achieved. In different populations of RLFs that change nonmonotonically with sound level, CaL either suppresses or enhances firing at sound levels that evoke maximum firing. CaL multiplies the gain of monotonic RLFs with dynamic range and divides the gain of nonmonotonic RLFs with the width of the RLF. These results suggest that a single broad class of calcium channels activates enhancing and suppressing local circuits to regulate the sensitivity of neuronal populations to sound level.

A layer-integrated approach for shallow water free-surface flow computation

2007 ◽  
Vol 24 (12) ◽  
pp. 1699-1722
Author(s):  
Meng-Chi Hung ◽  
Te-Yung Hsieh ◽  
Tung-Lin Tsai ◽  
Jinn-Chuang Yang
Keyword(s):  
Free Surface ◽  
Shallow Water ◽  
Free Surface Flow ◽  
Integrated Approach ◽  
Surface Flow ◽  
Flow Computation

Elevated Sound Levels within a Busy NICU

2005 ◽  
Vol 24 (6) ◽  
pp. 33-37 ◽  
Author(s):  
Charlene Krueger ◽  
Susan Wall ◽  
Leslie Parker ◽  
Rose Nealis
Keyword(s):  
Preterm Infants ◽  
Noise Level ◽  
Sound Level ◽  
Behavioral Effects ◽  
Outcome Variable ◽  
Sound Levels ◽  
Main Outcome Variable

Purpose: Elevated sound levels in the NICU may contribute to undesirable physiologic and behavioral effects in preterm infants. This study describes sound levels in a busy NICU in the southeastern U.S. and compares the findings with recommended NICU noise level standards.Design: NICU sound levels were recorded continuously at nine different locations within the NICU. Hourly measurements of loudness equivalent (Leq) sound level, sound level exceeded 10 percent of the time (L10), and maximum sound level (Lmax) were determined.Sample: Sound levels were sampled from nine different locations within the NICU.Main Outcome Variable: Sound levels are described using the hourly, A-weighted Leq, L10, and Lmax.Results: The overall average hourly Leq (M = 60.44 dB, range = 55–68 dB), L10 (M = 59.26 dB, range = 55–66 dB), and Lmax (M = 78.39, range = 69–93 dB) were often above the recommended sound levels (hourly Leq <50 dB, L10 <55 dB, and 1-second Lmax <70 dB). In addition, certain times of day, such as 6–7 AM and 10 AM–12 noon, were noisier than other times of day.

scholarly journals INFRASOUND AND LOW FREQUENCY NOISE IMMISION FROM PIPELINES. iMPROVING THE ISO 1996-2:2017 PROPOSED METHODS. CASES STUDIES CONDUCTED AT LOS ANDES AND PERUVIAN RAINFOREST

Akustika ◽  
2019 ◽  
Vol 32 ◽  
pp. 335-345
Author(s):  
Walter Montano
Keyword(s):  
Low Frequency ◽  
Sound Level ◽  
Frequency Noise ◽  
Gas Extraction ◽  
Howler Monkeys ◽  
Noise Sources ◽  
Industrial Facilities ◽  
Sound Levels ◽  
Continuous Noise ◽  
Amazonian Rainforest

The gas extraction wells are in Amazonian rainforest and by them there are their industrial facilities. The pipeline has about 800 km with four pumps stations and two compressor stations. The challenge of conducting sound measurements was important-there is no specialized literature-and other noise "sources" are howler monkeys, cicadidae chirping, woodpeckers, trees´foliage, etc. However the problem is simply because those fixed industrial facilities are the only ones. People live in isolated hamlet on the side of dirt roads, so they are exposed 24/7 to the continuous noise; at homes 4 km away from the plants the sound level is 60 dBC, but in the spectrum of ILFN tones could not be identified. This Paper presents the procedures that were developed to identify the ILFN tones, improving the methods proposed in ISO 1996-2, writing a software that "automatically eliminates" the sound levels that don´t belong to the industry,

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