Understanding and managing experiential aspects of soundscapes at Muir woods national monument

Integrating spatial-temporal soundscape mapping with landscape indicators for effective conservation management and planning of a protected area

Protected areas (PAs) possess generous biodiversity, making them great potential for human and wildlife well-being. Nevertheless, rising anthropogenic sounds may pose a serious challenge and threat to the habitats. Therefore, understanding the acoustic environments of PAs and implementing proper conservation strategies are essential for maintaining species richness within the territory. In this study, we investigate the spatial-temporal variations of soundscape distribution in the Dashanbao Protected Area (DPA) of China, ultimately discussing the planning and management strategies. Firstly, to systematically analyse the spatial-temporal soundscape distribution of the reserve, we generated single and multi-acoustic source maps by classifying geographical, biological, and anthropogenic sounds. In the region, we installed 35 recording points and collected sounds using the synchronic recording method. Secondly, we conducted Spearman correlation analyses to examine the relationships between the sound sources and i) temporal variations, ii) landscape feature indicators. Thirdly, we identified the dominant sound sources in the region and their conflict areas through the cross-analysis module of Grass Geographic Information Systems (GIS). Finally, we provided sound control strategies by discussing landscape indicators and land-use management policies. The results show that even though there is conservation planning in the DPA, anthropogenic sounds dominate in certain parts of the reserve depending on diurnal and seasonal cycles. This reveals deficiencies in the DPA's current planning concerning the soundscape and highlights the effectiveness of spatial-temporal mapping. Additionally, our correlation analyses demonstrate that landscape feature indicators can represent how sound environment is affected by landscape. The patch diversity (PD), landscape shape index (LSI), Shannon's Diversity Index (SHDI), woodland, shrubland, and water distance (WD) were identified as the primary predictors for both biological and anthropogenic sounds. None of the indicators exhibited a significant positive or negative correlation with geological sounds. Consequently, to enhance and conserve the acoustic quality of the region, spatial-temporal mapping with landscape indicators can be employed in the management and planning processes.

Understanding park visitors' soundscape perception using subjective and objective measurement

Environmental noise knows no boundaries, affecting even protected areas. Noise pollution, originating from both external and internal sources, imposes costs on these areas. It is associated with adverse health effects, while natural sounds contribute to cognitive and emotional improvements as ecosystem services. When it comes to parks, individual visitors hold unique perceptions of soundscapes, which can be shaped by various factors such as their motivations for visiting, personal norms, attitudes towards specific sounds, and expectations. In this study, we utilized linear models and geospatial data to evaluate how visitors' personal norms and attitudes, the park's acoustic environment, visitor counts, and the acoustic environment of visitors' neighborhoods influenced their perception of soundscapes at Muir Woods National Monument. Our findings indicate that visitors' subjective experiences had a greater impact on their perception of the park's soundscape compared to purely acoustic factors like sound level of the park itself. Specifically, we found that motivations to hear natural sounds, interference caused by noise, sensitivity to noise, and the sound levels of visitors' home neighborhoods influenced visitors' perception of the park's soundscape. Understanding how personal factors shape visitors' soundscape perception can assist urban and non-urban park planners in effectively managing visitor experiences and expectations.

Using aircraft tracking data to estimate the geographic scope of noise impacts from low-level overflights above parks and protected areas

Sightseeing air tours have proven to be a challenging management issue for many tourist destinations around the world, especially at locations meant to protect natural and cultural resources and wilderness character. Two of the primary challenges with managing air tours are a lack of information about their travel patterns and how such patterns result in a measurable noise impact to listeners. Recent studies have highlighted the usefulness of newer technology for tracking aircraft travel patterns, particularly over national parks. In this synthesis, we pair aircraft tracks with acoustic data using a quantitative observer-based audibility modelling software toolkit. The findings delimit the long-term geographic scope of audibility for specific aircraft noise sources above landscapes of Hawai'i Volcanoes and Denali National Parks, U.S. and identify practical, 3-dimensional offset distances that can be used to reduce the functional effects of air tour noise in terms of sound level.

Tranquillity in Urban Classical Chinese Gardens and Modern Parks: The Effect of Natural and Contextual Features

Parks and green spaces are an integral part of many urban areas. Such spaces offer a variety of psychological, physical and social benefits promoting a stronger sense of community and allowing people to cope better with everyday stress. These parks are often designed to provide tranquillity for people, and it is now an emerging area of policy in the promotion of quality of life. Tranquillity is considered a natural asset. Although they are vital, tranquil spaces are under threat, and it is, therefore, important to identify and understand such places so that they can be further planned and managed for the benefits that they provide. This study conceptualises the understanding of tranquillity and determines the extent to which a tranquil environment can be achieved. The study identified six parks referred to as “modern parks (MPs)” and “classical Chinese gardens (CCGs)”. Three parks each are located in Hong Kong and Guangzhou. Questionnaires were used to ascertain the importance of tranquil areas and the contribution of park components towards tranquillity. This study investigates the contribution of park elements that include both natural and contextual features. Furthermore, park characteristics and park elements were similarly identified. There were clear differences between natural and contextual features in terms of their potential contribution towards park users’ perceived tranquillity. There is also a striking importance and potential contribution of contextual features within classical Chinese gardens in relation to perceived tranquillity. This study concludes that there is the need to continue to enhance the quality of park spaces with regard to fostering tranquillity in urban areas.

Developing Connectedness to Nature in Urban Outdoor Settings: A Potential Pathway Through Awe, Solitude, and Leisure

Outdoor leisure experiences may represent an understudied yet effective pathway to promote connectedness to nature for urban park visitors. In contrast to outdoor recreation, this critical essay argues outdoor leisure more heavily emphasizes eudaimonic sentiments and intrinsic motivation in comparison with the goal-oriented and hedonic nature of outdoor recreation. It is further argued that two specific social psychological constructs, awe and solitude, may be especially useful in promoting leisure experiences in urban outdoor spaces. Relevant philosophical and social psychological literature is reviewed and synthesized to outline how land managers and environmental educators may facilitate experiences of awe and solitude to better promote contexts for experiencing outdoor leisure in urban parks. Specifically, reviewed literature suggests that utilizing the recreation opportunity spectrum framework and co-creative processes may be an effective path forward in better supporting urban park environments that are conducive to awe, solitude, and leisure. The review and synthesis of this research may ultimately guide environmental educators, land managers, and researchers in ways to more effectively support connectedness to nature via outdoor leisure experiences as an outcome for visitors to outdoor urban spaces.

Perception of National Park Soundscape and Its Effects on Visual Aesthetics

Soundscape perception is a very weak link in the national park landscape evaluation system in China. A thorough understanding of soundscapes and their effects on visual aesthetics is important for the management of national park landscapes. In this study, features of soundscapes (e.g., loudness, frequency, preference, and auditory satisfaction) were investigated based on 394 valid questionnaires of residents in the Qianjiangyuan National Park Pilot Area. The effects of soundscape on visual aesthetics were analyzed using the PLS-SEM. The results demonstrated that: (1) Peddling voice and insect sound were the loudest components in the soundscape, running water and birdsong were the most commonly heard and most preferred, religious sound was the quietest and least frequently heard, and horn was the least preferred. Residents in the Pilot Area were generally satisfied with the auditory environment. (2) Both sound frequency and preference have significant effects on auditory satisfaction, but preference (path coefficient = 0.426) has a larger effect than does frequency (path coefficient = 0.228). (3) Loudness has negligible effects on visual aesthetics, but other soundscape characteristics did influence visual aesthetics. Soundscape preference had the most significant effect (path coefficient = 0.305), followed by auditory satisfaction (path coefficient = 0.174), and sound frequency (path coefficient = 0.165). Among them, effects of perception frequency are the indirect utilities.

A stochastic simulation model for assessing the masking effects of road noise for wildlife, outdoor recreation, and bioacoustic monitoring

Traffic noise is one of the leading causes of reductions in animal abundances near roads. Acoustic masking of conspecific signals and adventitious cues is one mechanism that likely causes animals to abandon loud areas. However, masking effects can be difficult to document in situ and the effects of infrequent noise events may be impractical to study. Here, we present the Soundscapes model, a stochastic individual-based model that dynamically models the listening areas of animals searching for acoustic resources (“searchers"). The model also studies the masking effects of noise for human detections of the searchers. The model is set in a landscape adjacent to a road. Noise produced by vehicles traveling on that road is represented by calibrated spectra that vary with speed. Noise propagation is implemented using ISO-9613 procedures. We present demonstration simulations that quantify declines in searcher efficiency and human detection of searchers at relatively low traffic volumes, fewer than 50 vehicles per hour. Traffic noise is pervasive, and the Soundscapes model offers an extensible tool to study the effects of noise on bioacoustics monitoring, point-count surveys, the restorative value of natural soundscapes, and auditory performance in an ecological context.

Soundscapes and protected area conservation: Are noises in nature making people complacent?

This study explores how existing connections to natural places may affect PA visitors’ experiences and perceptions within the PA. Specifically, outside-the-PA soundscape perceptions are examined to better understand how their experiences outside the PA may affect perceptions of PA soundscapes and visitors’ ability to effectively contribute to conservation monitoring. Survey research (n=389) of recent urban visitors to the Chilean Coyhaique National Reserve (CNR) in Patagonia unpacked perceptions of the acoustic environments within the places where participants felt most connected to nature, including landscape features, favorite and prevalent sounds, and acceptability of particular anthrophonic sounds. Favorite and prevalent sounds were open-coded, and anthrophonic sounds were rated for prevalence and acceptability. The mountain landscape features and sounds (‘wind’, ‘running water’,‘ birds’) participants described as prominent within the places where they felt most connected to nature aligned well with CNR characteristics. Participants who ‘sometimes’‘/often’ heard certain anthropogenic sounds (vehicles, aircraft, machines, city sounds), within the places where they felt most connected to nature, rated those sounds as more acceptable than participants who reported ‘never’ hearing them, raising concerns about complacency toward anthrophony in natural settings. Continued research efforts are warranted to better understand visitors’ frames of reference, their influence on the reliability of social norm data for PA soundscape monitoring, and their influence on PA managers’ ability to protect conservation values.

Electroencephalography (EEG)-Based Neural Emotional Response to the Vegetation Density and Integrated Sound Environment in a Green Space

Emotion plays an important role in physical and mental health. Green space is an environment conducive to physical and mental recovery and influences human emotions through visual and auditory stimulation. Both the visual environment and sound environment of a green space are important factors affecting its quality. Most of the previous relevant studies have focused solely on the visual or sound environment of green spaces and its impacts. This study focused on the combination of vegetation density (VD) and integrated sound environment (ISE) based on neural emotional evaluation criteria. VD was used as the visual variable, with three levels: high (H), moderate (M) and low (L). ISE was used as the sound variable, with four levels: low-decibel natural and low-decibel artificial sounds (LL), low-decibel natural and high-decibel artificial sounds (LH), high-decibel natural and low-decibel artificial sounds (HL) and high-decibel natural and high-decibel artificial sounds (HH). These two variables were combined into 12 unique groups. A total of 360 volunteer college students were recruited and randomly assigned to the 12 groups (N = 30). All 12 groups underwent the same 5 min high-pressure learning task (pretest baseline), followed by a 5 min audio-visual recovery (posttest). Six indicators of neural emotion (engagement, excitement, focus, interest, relaxation and stress) were dynamically measured by an Emotiv EPOC X device during the pretest and posttest. Analysis of covariance was used to determine the main and coupled effects of the variables. (1) VD and ISE have significant effects on human neural emotions. In moderate- and high-VD spaces, artificial sound levels may have a positive effect on excitement. (2) A higher VD is more likely to result in excitatory neural emotion expression. (3) Low-VD and high-VD spaces have a higher degree of visual continuity. Both extremely low and extremely high VDs result in a higher expression of stressful emotions than observed for a moderate VD. (4) High-decibel artificial sounds are more likely to attract attention, possibly because artificial sounds are easier to recognize than natural sounds. However, when both the natural and artificial sounds are low, it is difficult to induce higher tones, and the lower the artificial sound decibel level, the easier it is to relax. Additionally, under the influence of an ISE, attention recovery and stress recovery may be negatively correlated. The results show that an appropriate combination of VD and ISE can improve the health benefits of a green space and thus the well-being of visitors.

Exploring the perceived restorativeness of natural soundscapes under the global pandemic of COVID-19: A moderated mediation model

Although emerging studies have discussed the potential benefits of soundscape in mental restoration, few have investigated how soundscape renews and re-energizes people, especially in facing the current public challenge of the COVID-19 crisis. We established a moderated mediation model to examine the relationship of the four restorative components of soundscape: being away, compatibility, extent and fascination. The data were collected in Xixi Wetland National Park, China, before the outbreak of COVID-19 (n = 562) in October 2019 and post COVID-19 in October 2020 (n = 341). The results revealed that natural soundscapes have great restorative benefits for visitors. The inter relationships of the restorative components are moderated by the perceived stress level which show significant different before and after the COVID-19 pandemic. The post-COVID-19 visitors reported a higher level of stress while natural soundscapes had greater effects on their mental restoration. The direct effects of extent and fascination as well as the mediating effects of fascination were stronger among the post-COVID-19 group. However, the path coefficient from being away to compatibility were higher in the pre-COVID-19 group. This study improves the current understanding of the interactive mechanism among the restorative components of soundscape. Knowledge about natural soundscape encourages practitioners to consider it as a guideline for the creation of sustainable environments, especially under the COVID-19 crisis.

Thinking Outside the Park: Connecting Visitors’ Sound Affect in a Nature-Based Tourism Setting with Perceptions of Their Urban Home and Work Soundscapes

This study examined the potential for Perceived Affective Quality (PAQ; pleasantness, eventfulness, familiarity) soundscape measures developed within urban settings to enrich current soundscape management approaches within protected areas (PAs). Drawing on the premise that people bring experiences from other life contexts into PA settings and PA visitors are increasingly coming from urban areas, research integrated urban visitors’ soundscape perceptions of their home and work acoustic environments with their perceptions of acoustic environments in PAs. Two-phased survey research (n = 333) separated visitors into urban density groups and compared PAQ variables across home, work, and PA contexts. Significant differences resulted, both in ratings of the three acoustic contexts (PA, home, work) for all three PAQ components and between urban density groups. The importance of pleasantness was confirmed across all contexts; however, alone, this dimension lacked sufficient contrast to interpret the complexity of soundscape perceptions, especially considering diverse Healthy Parks, Healthy People (HPHP) visitor experience scenarios and goals. Thus, managers should consider (1) additional PAQ variables that can provide more useful and contrasting information; (2) incorporating methods that integrate PAQ measures across visitors’ different acoustic contexts, and (3) including urban density measures within HPHP research.

Listening to Forests: Comparing the Perceived Restorative Characteristics of Natural Soundscapes before and after the COVID-19 Pandemic

Natural sounds are known to contribute to health and well-being. However, few studies have investigated what makes a natural sound renew and re-energize people, especially in the face of significant stressors caused by the Corona Virus Disease 2019 (COVID-19). This study examined the interactive mechanism towards the perceived restorative characteristics of natural soundscapes: fascination, being-away, compatibility, and extent. Two groups of data were collected in Burleigh Heads National Park, Australia, before the outbreak of COVID-19 (n = 526) and in October 2020 (n = 371). The objective measures of LAeq confirmed that the acoustic environment of Burleigh Heads National Park are quiet and peaceful for attention restoration. The results of the subject evaluation revealed that participants from the post-COVID-19 group reported higher stress levels, while there was a greater mental restoration through water sounds. There are significant differences between the pre- and post-COVID-19 groups with respect to the relationships among the perceived restorative characteristics of natural soundscapes. The direct effects of extent and fascination, as well as the mediating effects of fascination, were more significant among the post-COVID-19 group than the pre-COVID-19 group. However, the effects of being-away on compatibility were less significant in the post-COVID-19 group. This study reduces the gap that exists on the research of environment–people–health–wellbeing nexus. Knowledge about natural soundscapes encourages administrations to consider it as a guideline for the planning and management of natural resources, especially during the COVID-19 pandemic.

The phantom chorus: birdsong boosts human well-being in protected areas

Spending time in nature is known to benefit human health and well-being, but evidence is mixed as to whether biodiversity or perceptions of biodiversity contribute to these benefits. Perhaps more importantly, little is known about the sensory modalities by which humans perceive biodiversity and obtain benefits from their interactions with nature. Here, we used a 'phantom birdsong chorus' consisting of hidden speakers to experimentally increase audible birdsong biodiversity during 'on' and 'off' (i.e. ambient conditions) blocks on two trails to study the role of audition in biodiversity perception and self-reported well-being among hikers. Hikers exposed to the phantom chorus reported higher levels of restorative effects compared to those that experienced ambient conditions on both trails; however, increased restorative effects were directly linked to the phantom chorus on one trail and indirectly linked to the phantom chorus on the other trail through perceptions of avian biodiversity. Our findings add to a growing body of evidence linking mental health to nature experiences and suggest that audition is an important modality by which natural environments confer restorative effects. Finally, our results suggest that maintaining or improving natural soundscapes within protected areas may be an important component to maximizing human experiences.

Rapid Resource Change and Visitor-Use Management: Social-ecological Connections at the Bonneville Salt Flats

Parks and protected areas are complex, and managers often need integrated social-ecological science-based information that illuminates the dynamic interactions between the biophysical and social processes. However, modeling and determining social-ecological connections are difficult due to disciplinary paradigms, divergent research questions, and data sets representing different scales. During this investigation, researchers sought to evaluate social-ecological linkages at a large salt pan (Bonneville Salt Flats) in western Utah (US). Specifically, the investigation evaluated how the changing level and location of salt-crust moisture and ponding water influenced visitors' spatial distribution of use and important elements of their experience. The findings indicate that visitors travel more distance, spend more time recreating, and use the Salt Flats in higher densities during dry conditions. However, the results also highlight that importance levels ascribed to specific aspects of the visitor experience remained relatively stable regardless of changes in salt-crust moisture and ponding water. Illuminating such linkages is important because most natural resource issues in society, including resources at the Bonneville Salt Flats, are not solely ecological or social in nature but characterized by deeper enmeshment between the two.

Personal Audiovisual Aptitude Influences the Interaction Between Landscape and Soundscape Appraisal

It has been established that there is an interaction between audition and vision in the appraisal of our living environment, and that this appraisal is influenced by personal factors. Here, we test the hypothesis that audiovisual aptitude influences appraisal of our sonic and visual environment. To measure audiovisual aptitude, an auditory deviant detection experiment was conducted in an ecologically valid and complex context. This experiment allows us to distinguish between accurate and less accurate listeners. Additionally, it allows to distinguish between participants that are easily visually distracted and those who are not. To do so, two previously conducted laboratory experiments were re-analyzed. The first experiment focuses on self-reported noise annoyance in a living room context, whereas the second experiment focuses on the perceived pleasantness of using outdoor public spaces. In the first experiment, the influence of visibility of vegetation on self-reported noise annoyance was modified by audiovisual aptitude. In the second one, it was found that the overall appraisal of walking across a bridge is influenced by audiovisual aptitude, in particular when a visually intrusive noise barrier is used to reduce highway traffic noise levels. We conclude that audiovisual aptitude may affect the appraisal of the living environment.

Motorized Recreation Sounds Influence Nature Scene Evaluations: The Role of Attitude Moderators

Soundscape assessment takes many forms, including letting the consequences of the soundscape be an indicator of soundscape quality or value. As a result, much social science research has been conducted to better quantify problem soundscapes and the subsequent effects on humans exposed to them. Visual evaluations of natural environments are one area where research has consistently shown detrimental effects of noisy or anthropogenic soundscapes (e.g., those containing noise from motorized recreation), but the potential moderating role of individual attitudes toward elements within the soundscape has not been sufficiently explored. This study demonstrates that both pro-motorized recreation and pro-motorized recreation management attitudes can alter the effect of motorized recreation noise on scenic evaluations in opposing directions. Pro-recreation attitudes lessen the effect of the soundscape, while pro-management attitudes heighten the negative effect of anthropogenic sounds on scenic evaluation. The implications for other areas of soundscape research, especially with regard to soundscape quality assessment through experienced outcomes, are discussed, including possible strategies for prioritizing known or relevant moderating variables.

Acoustic environments matter: Synergistic benefits to humans and ecological communities

Protected areas are critical locations worldwide for biodiversity preservation and offer important opportunities for increasingly urbanized humans to experience nature. However, biodiversity preservation and visitor access are often at odds and creative solutions are needed to safeguard protected area natural resources in the face of high visitor use. Managing human impacts to natural soundscapes could serve as a powerful tool for resolving these conflicting objectives. Here, we review emerging research that demonstrates that the acoustic environment is critical to wildlife and that sounds shape the quality of nature-based experiences for humans. Human-made noise is known to affect animal behavior, distributions and reproductive success, and the organization of ecological communities. Additionally, new research suggests that interactions with nature, including natural sounds, confer benefits to human welfare termed psychological ecosystem services. In areas influenced by noise, elevated human-made noise not only limits the variety and abundance of organisms accessible to outdoor recreationists, but also impairs their capacity to perceive the wildlife that remains. Thus soundscape changes can degrade, and potentially limit the benefits derived from experiences with nature via indirect and direct mechanisms. We discuss the effects of noise on wildlife and visitors through the concept of listening area and demonstrate how the perceptual worlds of both birds and humans are reduced by noise. Finally, we discuss how management of soundscapes in protected areas may be an innovative solution to safeguarding both and recommend several key questions and research directions to stimulate new research.

A Review of the Benefits of Nature Experiences: More Than Meets the Eye

Evidence that experiences of nature can benefit people has accumulated rapidly. Yet perhaps because of the domination of the visual sense in humans, most research has focused on the visual aspects of nature experiences. However, humans are multisensory, and it seems likely that many benefits are delivered through the non-visual senses and these are potentially avenues through which a physiological mechanism could occur. Here we review the evidence around these lesser studied sensory pathways—through sound, smell, taste, touch, and three non-sensory pathways. Natural sounds and smells underpin experiences of nature for many people, and this may well be rooted in evolutionary psychology. Tactile experiences of nature, particularly beyond animal petting, are understudied yet potentially fundamentally important. Tastes of nature, through growing and consuming natural foods, have been linked with a range of health and well-being benefits. Beyond the five senses, evidence is emerging for other non-visual pathways for nature experiences to be effective. These include ingestion or inhalation of phytoncides, negative air ions and microbes. We conclude that (i) these non-visual avenues are potentially important for delivering benefits from nature experiences; (ii) the evidence base is relatively weak and often based on correlational studies; and (iii) deeper exploration of these sensory and non-sensory avenues is needed.

The relationship between aircraft noise exposure and day-use visitor survey responses in backcountry areas of national parks

To evaluate the relationship between aircraft noise exposure and the quality of national park visitor experience, more than 4600 visitor surveys were collected at seven backcountry sites in four U.S. national parks simultaneously with calibrated sound level measurements. Multilevel logistic regression was used to estimate parameters describing the relationship among visitor responses, aircraft noise dose metrics, and mediator variables. For the regression models, survey responses were converted to three dichotomous variables, representing visitors who did or did not experience slightly or more, moderately or more, or very or more annoyance or interference with natural quiet from aircraft noise. Models with the most predictive power included noise dose metrics of sound exposure level, percent time aircraft were audible, and percentage energy due to helicopters and fixed-wing propeller aircraft. These models also included mediator variables: visitor ratings of the "importance of calmness, peace and tranquility," visitor group composition (adults or both adults and children), first visit to the site, previously taken an air tour, and participation in bird-watching or interpretive talks. The results complement and extend previous research conducted in frontcountry areas and will inform evaluations of air tour noise effects on visitors to national parks and remote wilderness sites.

Perception of urban park soundscape

A number of studies have been initiated to explore how to improve the soundscape quality in urban parks. However, good soundscape quality in parks cannot be provided without a thorough understanding of the complex relationships among sound, environment, and individuals. As acoustic comfort is considered to be an important outcome of soundscape quality, this study investigates the relative impacts of the factors influencing acoustic comfort evaluation by formulating a multivariate ordered logit model. This study also explores the inter-relationships among acoustic comfort evaluation, acceptability of the environment, and preference to stay in a park using a path model. A total of 595 valid responses were obtained from interview surveys administered in four parks in Hong Kong while objective sound measurements were carried out at the survey spots concurrently. The findings unveil that acoustic comfort evaluation, besides visual comfort evaluation of landscape, also plays an important role on users' acceptability of the urban park environment. Compared with all the studied acoustic related factors, acoustic comfort evaluation serves as a better proxy for park users' preference to stay in urban parks. Hearing the breeze will significantly increase the likelihood of individuals in giving high acoustic comfort evaluation. Conversely, hearing the sounds from heavy vehicles or sounds from bikes will significantly reduce the likelihood in giving a high acoustic evaluation.

Effects of soundscapes on perceived crowding and encounter norms

Soundscapes in recreation settings are becoming an important issue, but there are few studies of the effects of sounds on recreation experiences, especially crowding perceptions and encounter norms. This study compared effects of six types of sounds (an airplane, a truck engine, children playing, birds, water, and a control) on perceived crowding (PC) and encounter norms for hikers. Data were collected from 47 college students through lab experiments using simulated images, with moving hikers inserted in the original photo taken in the Jungmeori area of Mudeungsan Provincial Park in Korea. Overall, the motor-made sounds of the airplane and truck engine increased PC and decreased acceptability ratings, and the natural sounds of birds and water decreased PC and increased acceptability ratings. Ratings of the sound of children playing were similar to those in the control (i.e., no sound). In addition, as numbers of hikers increased, the overall effects of sounds decreased, and there were few significant differences in PC or acceptability ratings at the highest encounter levels. Theoretical and methodological implications are discussed.

Reducing visitor noise levels at Muir Woods National Monument using experimental management

Noise impacts resources and visitor experience in many protected natural areas, and visitors can be the dominant source of noise. This experimental study tested the efficacy and acceptability of signs asking visitors to be quiet at Muir Woods National Monument, California. Signs declaring a "quiet zone" (at the park's Cathedral Grove) or a "quiet day" (throughout the park) were posted on a randomized schedule that included control days (no signs). Visitor surveys were conducted to measure the cognitive and behavioral responses of visitors to the signs and test the acceptability of these management practices to visitors. Visitors were highly supportive of these management practices and reported that they consciously limited the amount of noise they produced. Sound level measurements showed substantial decreases on days when signs were posted.

Effects of changed aircraft noise exposure on experiential qualities of outdoor recreational areas

The literature indicates that sound and visual stimuli interact in the impression of landscapes. This paper examines the relationship between annoyance with sound from aircraft and annoyance with other area problems (e.g., careless bicycle riding, crowding, etc.), and how changes in noise exposure influence the perceived overall recreational quality of outdoor recreational areas. A panel study (telephone interviews) conducted before and after the relocation of Norway's main airport in 1998 examined effects of decreased or increased noise exposure in nearby recreational areas (n = 591/455). Sound from aircraft annoyed the largest proportion of recreationists, except near the old airport after the change. The decrease in annoyance with sound from aircraft was accompanied by significant decreases in annoyance with most of the other area problems. Near the new airport annoyance with most factors beside sound from aircraft increased slightly, but not significantly. A relationship between aircraft noise annoyance and perceived overall recreational quality of the areas was found.