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13 publications listed under Blue spaces

The Restorative Power of Blue Spaces: A 19-Country Study

2026 / Blue spaces, Health and well-being

Living in urbanised areas can deplete cognitive and emotional resources. To help restore them, many people seek out natural locations. Blue spaces (e.g. rivers, lakes, coasts) are among people’s favourite restorative settings, but we know little about the importance of type or quality for psychological restoration, or the role of nature connectedness. Using survey data from 19 countries (n = 17,131), we explored the extent to which participants perceived a recent blue space visit had helped them “rest and recover [their] abilities to focus” and feel “part of nature”. Seventeen blue space types were investigated, spanning marine, lentic (‘standing’) inland, and lotic (‘flowing’) inland waters in both more natural and more built settings, respectively. Accounting for country differences, linear mixed models found all blue space settings were recalled as restorative, with sandy beaches and rural rivers/canals the most, and marshlands the least. Recalled nature connectedness was also high overall, although more natural blue spaces consistently scored higher than built ones. Perceived safety was the quality indicator most associated with both outcomes. Actively engaging with the water (e.g. swimming, paddling) was associated with greater restoration than remaining on-land, and both outcomes showed diminishing marginal returns over time, peaking around 3 h. Path analysis focusing on walking (the most common visit activity) suggested a reciprocal relationship between perceived restoration and nature connectedness. Results provide multi-country evidence that spending recreational time at safe blue spaces can benefit diverse populations by helping them to restore depleted cognitive/emotional resources and connect with the natural world.

Visitor Perception of Lake Water Quality in Two Highly Managed Urban Lakes in Saint Paul, Minnesota

2026 / Blue spaces

Urban lakes provide important recreational and aesthetic benefits but often require intensive management to restore and maintain water quality. However, if there are mismatches between measured and perceived water quality, improvements may go unnoticed. While conventional water quality indicators such as chlorophyll a and Secchi depth are routinely monitored, it remains unclear how well these biophysical metrics align with public perceptions. We conducted a survey to measure visitors’ perceptions of water quality at two highly visited urban lakes in Saint Paul, Minnesota—Como Lake, a shallow eutrophic lake undergoing intensive in-lake management, and Lake Phalen, a deeper mesotrophic lake with fewer recent interventions. Across three years (2022–2024), we recruited over 800 survey respondents via signage that encouraged volunteers to participate by exchanging text-messages with a custom chatbot. Comparing long-term open water measurements with visitors’ water quality scores showed mixed relationships with chlorophyll a levels. Visitor perception scores were lower for eutrophic Como Lake, but this difference was small relative to the four-fold difference in chlorophyll a concentrations between the lakes. Open-ended responses suggest that visitors base their evaluations on a combination of visual cues such as water clarity, trash, and aquatic vegetation. These findings underscore the complexity of human–lake interactions and suggest that perception of ecological conditions may be informed by additional factors including expectations, communication, and lake-specific context. Incorporating visitor perception into lake monitoring and management may help align restoration goals with visitor experiences in urban settings.

Will Biodiversity Actions Yield Healthy Places? A Systematic Review of Human Health Outcomes Associated With Biodiversity-Focused Urban Greening

2025 / Biodiversity, Blue spaces, Green spaces, Health and well-being, Systematic Review, Urban

Figure 1. Seven biodiversity-supporting elements in urban landscapes and definitions for each. Biodiversity-supporting elements are adapted from Spotswood et al. (2019). There is growing interest in using urban greening projects to support biodiversity. While there are many potential co-benefits, the health outcomes resulting from biodiversity-supporting activities have yet to be synthesized. We conducted a systematic review of health outcomes associated with seven biodiversity-supporting elements, including patch size, connections, matrix quality, habitat diversity, native plants, special resources and vegetation management. We identified 1550 studies linking elements with human health. Results show that many types of biodiversity-supporting elements are associated with a wide range of positive health outcomes. These outcomes included improved physical and mental health, increased physical activity, improved childhood development, social outcomes, and reduced exposure to harms such as sun, heat, and pollution (including light, air and noise). Other biodiversity-supporting elements such as reducing pesticide use, native plants, and habitat diversity were associated with a smaller and more specific range of health outcomes. While most findings showed positive associations between biodiversity-supporting elements and health, many also yielded mixed, neutral, or negative findings. Further, most identified study designs were observational, limiting our ability to uncover causality. We found that studies using a natural experimental design yielded a greater fraction of mixed, neutral, and negative findings compared to observational designs (the majority of studies) and experimental studies (largely short term in nature). These results confirm concerns about the strength of research findings built largely on correlational research designs. We also identify areas of trade-off between biodiversity-supporting elements and human health. These include actions that positively affect health yet negatively impact biodiversity, such as the maintenance of sports fields and trails in parks that can negatively impact habitat and disrupt wildlife behaviour. Biodiversity-supporting elements can also negatively impact some dimensions of human health, including by increasing human–wildlife conflict, disease vectors, allergenic pollen, biogenic volatile organic compounds (BVOCs), through and green gentrification. Our review reveals a large potential for co-benefits for human health to come from biodiversity-focused actions in cities. Careful attention to minimizing tensions and trade-offs could help to reduce the potential for conflict between biodiversity and human health objectives.

What Types of Nature Exposure Are Associated With Hedonic, Eudaimonic and Evaluative Wellbeing? An 18-Country Study

2024 / Blue spaces, Green spaces, Health and well-being

Figure 2. Summary of fully adjusted models of all dimensions of SWB and residential availability and visits to green space, coastal blue space and freshwater blue space. Although spending time in nature can improve subjective wellbeing (SWB), little is known about how different types of nature exposure are associated with different dimensions of SWB or the consistency of associations across national/cultural contexts. Using data from 18 countries, associations between green, coastal and freshwater blue space exposures (including residential availability, visits ‘yesterday’ and visits in the previous four weeks) and hedonic, eudaimonic, and evaluative wellbeing were estimated. Overall, residential nature availability showed little association with any wellbeing outcome, whereas visiting green and coastal locations ‘yesterday’ was associated with better hedonic wellbeing. Although frequently visiting green, coastal and freshwater spaces were all associated with greater evaluative wellbeing, greater eudaimonic wellbeing was only associated with frequent visits to green and freshwater spaces. Variations existed across countries. Results suggest that different types of nature exposure vary in their association with different dimensions of SWB. Understanding these differences may help us maximise the potential of natural environments as SWB-promoting resources.

Applying an Ecosystem Services Framework on Nature and Mental Health to Recreational Blue Space Visits Across 18 Countries

2023 / Blue spaces

The effects of nature on mental health and subjective well-being have yet to be consistently integrated into ecosystem service models and frameworks. To address this gap, we used data on subjective mental well-being from an 18-country survey to test a conceptual model integrating mental health with ecosystem services, initially proposed by Bratman et al. We analysed a range of individual and contextual factors in the context of 14,998 recreational visits to blue spaces, outdoor environments which prominently feature water. Consistent with the conceptual model, subjective mental well-being outcomes were dependent upon on a complex interplay of environmental type and quality, visit characteristics, and individual factors. These results have implications for public health and environmental management, as they may help identify the bluespace locations, environmental features, and key activities, that are most likely to impact well-being, but also potentially affect recreational demand on fragile aquatic ecosystems.

Beyond “Bluespace” and “Greenspace”: A Narrative Review of Possible Health Benefits from Exposure to Other Natural Landscapes

2023 / Blue spaces, Green spaces

Graphical abstract: Does exposure to natural landscapes not dominated by plants or liquid-water influence human health? Numerous studies have highlighted the physical and mental health benefits of contact with nature, typically in landscapes characterized by plants (i.e., “greenspace”) and water (i.e., “bluespace”). However, natural landscapes are not always green or blue, and the effects of other landscapes are worth attention. This narrative review attempts to overcome this limitation of past research. Rather than focusing on colors, we propose that natural landscapes are composed of at least one of three components: (1) plants (e.g., trees, flowering plants, grasses, sedges, mosses, ferns, and algae), (2) water (e.g., rivers, canals, lakes, and oceans), and/or (3) rocks and minerals, including soil. Landscapes not dominated by plants or liquid-state water include those with abundant solid-state water (e.g., polar spaces) and rocks or minerals (e.g., deserts and caves). Possible health benefits of solid-state water or rock/mineral dominated landscapes include both shorter-term (e.g., viewing images) and longer-term (e.g., living in these landscapes) exposure durations. Reported benefits span improved emotional and mental states and medical treatment resources for respiratory conditions and allergies. Mechanisms underlying the health benefits of exposure consist of commonly discussed theories in the “greenspace” and “bluespace” literature (i.e., instoration and restoration) as well as less discussed pathways in that literature (i.e., post-traumatic growth, self-determination, supportive environment theory, and place attachment). This is the first review to draw attention to the potential salutogenic value of natural landscapes beyond “greenspace” and “bluespace.” It is also among the first to highlight the limitations and confusion that result from classifying natural landscapes using color. Since the extant literature on natural landscapes – beyond those with abundant plants or liquid-state water – is limited in regard to quantity and quality, additional research is needed to understand their restorative potential and therapeutic possibilities.

Mechanisms Underlying Childhood Exposure to Blue Spaces and Adult Subjective Well-Being: An 18-Country Analysis

2022 / Blue spaces

Figure 1. Conceptual model linking childhood exposure to blue spaces to adult subjective well-being with serial-parallel mediation through intrinsic motivation and recent visits to blue and green spaces (solid lines = indirect paths, dotted lines = direct paths). Contact with natural environments is associated with good health and well-being. Although childhood nature experiences may be important in the development of an individual’s relationship with nature and subsequent well-being, previous studies have tended to focus on ‘nature’ in general, and the mechanisms by which childhood experiences influence well-being in adulthood remain insufficiently studied. Drawing on cross-sectional survey data from an 18-country sample (N = 15,743) the current work extended previous research by examining: a) blue spaces (coasts, rivers, lakes, etc.) in particular; b) associations between adults’ recalled childhood exposure to blue spaces, frequency of recent visits to green and blues spaces, and adult subjective well-being; c) the role of childhood exposure to blue spaces on intrinsic motivations to spend time in nature; and d) the consistency of these relationships across different countries. Tests of a model where childhood exposure to blue spaces was linked to adult subjective well-being serially through intrinsic motivation and then recent blue and green space visits exhibited a good fit, a pattern largely consistent across all 18 countries. However, an alternative model where recent visits predicted intrinsic motivation also demonstrated good fit, indicating that these processes may be iterative. Building familiarity with and confidence in and around blue spaces in childhood may stimulate a joy of, and greater propensity to spend recreational time in, nature in adulthood, with positive consequences for adult subjective well-being.

Associations Between Green/Blue Spaces and Mental Health Across 18 Countries

2021 / Blue spaces, Green spaces, Health and well-being

Figure 1. Relationships between: (1) Green space visits in last 4 weeks, (2) Inland-blue space visits in last 4 weeks, (3) Coastal-blue space visits in last 4 weeks, and (4) nature connectedness (1–7); and positive well-being (0–100; a,e,l,m), risk of mental distress (0–1; b,f,j,n), use of depression medication (0–1; c,g,k,o), and use of anxiety medication (0–1; d,h,l,p), averaged across 18 countries (n = 16,302). Living near, recreating in, and feeling psychologically connected to, the natural world are all associated with better mental health, but many exposure-related questions remain. Using data from an 18-country survey (n = 16,307) we explored associations between multiple measures of mental health (positive well-being, mental distress, depression/anxiety medication use) and: (a) exposures (residential/recreational visits) to different natural settings (green/inland-blue/coastal-blue spaces); and (b) nature connectedness, across season and country. People who lived in greener/coastal neighbourhoods reported higher positive well-being, but this association largely disappeared when recreational visits were controlled for. Frequency of recreational visits to green, inland-blue, and coastal-blue spaces in the last 4 weeks were all positively associated with positive well-being and negatively associated with mental distress. Associations with green space visits were relatively consistent across seasons and countries but associations with blue space visits showed greater heterogeneity. Nature connectedness was also positively associated with positive well-being and negatively associated with mental distress and was, along with green space visits, associated with a lower likelihood of using medication for depression. By contrast inland-blue space visits were associated with a greater likelihood of using anxiety medication. Results highlight the benefits of multi-exposure, multi-response, multi-country studies in exploring complexity in nature-health associations.

Casting a Wide Net and Making the Most of the Catch

2021 / Blue spaces, College students, Development, Underserved populations

Usha Varanasi describes lessons learned and the people and principles that influenced six decades of professional endeavours from graduate schools to ascending, often unexpectedly, the science and management ladder in National Oceanic and Atmospheric Administration (NOAA) Fisheries, which manages US living marine resources. For this woman chemist from India, the twists of fate and love of adventure presented amazing opportunities as well as challenges. Her research on cetacean biosonar as well as on the impact of fossil fuel pollution on seafood safety and the health of marine organisms taught her the value of multidisciplinary approaches and unusual alliances. Transitioning into management, and eventually as the director of Northwest Fisheries Science Center, Usha learned the value of transparency and empathy while communicating our results to impacted communities, and the resolve to support the science regardless of the consequences. Her advice to young professionals is that the journey should be as fulfilling as reaching the goalpost.

Taking the Long View for Oceans and Human Health Connection through Community-Driven Science

2021 / Blue spaces, Community science, Health and well-being, Indigenous communities, Reciprocal healing

Figure 1. Olympic Region Harmful Algal Bloom (ORHAB) partners and sampling sites. The most proactive approach to resolving current health and climate crises will require a long view, focused on establishing and fostering partnerships to identify and eliminate root causes of the disconnect between humans and nature. We describe the lessons learned through a unique scientific partnership that addresses a specific crisis, harmful algal blooms (HABs), along the northeast Pacific Ocean coast, that blends current-day technology with observational knowledge of Indigenous communities. This integrative scientific strategy resulted in creative solutions for forecasting and managing HAB risk in the Pacific Northwest as a part of the US Ocean and Human Health (OHH) program. Specific OHH projects focused on: Understanding genetic responses of Tribal members to toxins in the marine environment Knowledge sharing by elders during youth camps Establishing an early warning program to alert resource managers of HABs are explicit examples of proactive strategies used to address environmental problems. The research and monitoring projects with Tribal communities taught the collaborating non-Indigenous scientists the value of reciprocity, highlighting both the benefits from and protection of oceans that promote our well-being. Effective global oceans and human health initiatives require a collective action that gives equal respect to all voices to promote forward thinking solutions for ocean health.

Protecting Health in Dry Cities: Considerations for Policy Makers

2020 / Blue spaces, Green spaces

Water has always been essential for cities to survive and thrive. The earliest cities, from 4000 BC, were founded near water sources. Conversely, water scarcity might have contributed to the demise of ancient cities such as Tikal in present day Guatemala and Angkor in present day Cambodia. Water deprivation was also used as a weapon in ancient times; when Sennacherib of Assyria ransacked Babylon in 689 BC, he destroyed the city’s water supply. Dry cities present complex challenges in a dynamic world. The supply of water in many cities will increasingly fall short of demand, with diverse and potentially severe effects on health. In a world of pervasive inequalities, water scarcity is likely to hit the most vulnerable hardest. The challenge of achieving health in dry cities is intensified in the setting of resource scarcity, state and societal fragility, and weak institutions. The inter-relation between human health and the environment needs to be central to planning and management of both water and health systems. Promoting health and wellbeing in dry cities is essential to achieving the sustainable development goals. Innovation will be key to progress; it requires foresight, strong institutions, and action from many people.

Research Note: Residential Distance and Recreational Visits to Coastal and Inland Blue Spaces in Eighteen Countries

2020 / Blue spaces, Health and well-being, Recreation

Figure 1. Given residential locations (correct to three decimal degrees) of the 15,216 respondents included in analysis. The map of Spain includes respondents resident in the autonomous city of Melilla. Respondents resident in the Canary Islands, Azores, and Madeira are not displayed. Varied categorisations of residential distance to bluespace in population health studies make comparisons difficult. Using survey data from eighteen countries, we modelled relationships between residential distance to blue spaces (coasts, lakes, and rivers), and self-reported recreational visits to these environments at least weekly, with penalised regression splines. We observed exponential declines in visit probability with increasing distance to all three environments and demonstrated the utility of derived categorisations. These categories may be broadly applicable in future research where the assumed underlying mechanism between residential distance to a blue space and a health outcome is direct recreational contact.

Assessing the Value of the U.S. Roadless Rule for People and Nature

2026 / Blue spaces, Public land, Recreation

For more than a century, forest policy in the United States has recognized the importance of protecting forested watersheds to safeguard water resources. The 2001 U.S. Forest Service Roadless Area Conservation Rule (Roadless Rule) established Inventoried Roadless Areas (IRAs) across approximately 60 million acres of National Forest System lands to sustain high-quality soil, water, biodiversity, and recreational values by restricting road building and commercial timber harvest. Because IRAs are administratively designated rather than legislatively protected, they remain vulnerable to policy reversals. Recent efforts to rescind the Roadless Rule have renewed concerns about potential ecological and economic consequences. Here, we assess vulnerabilities to weakened protections under the Roadless Rule by quantifying the benefits IRAs provide for river protection, clean water provisioning, recreational opportunities, and aquatic biodiversity across the conterminous United States. We find that IRAs protect over 130,000 kms of streams and rivers, representing 2.5% of total river length, and serve as the primary protection mechanism for more than 100,000 kms of rivers (1.9%) when accounting for other regulatory and conservation frameworks. These protections are geographically widespread and particularly important in regions with limited alternative safeguards. IRA-influenced watersheds supply drinking water to at least 25 million Americans, with several states sourcing water for over one-third of their populations from these areas. Proximity of National Forests to urban centers amplifies these benefits, even in states with relatively small IRA extents. In addition, IRA-protected watersheds overlap substantially with high-demand hunting and fishing areas and support diverse aquatic biodiversity. Our results demonstrate that rescinding the Roadless Rule would diminish protections for rivers, and may compromise drinking water quality and affordability, reduce recreational opportunities, and threaten freshwater biodiversity. Safeguarding Roadless Rule protections is therefore essential for sustaining ecosystem services, supporting human well-being, and advancing broader conservation and resilience goals under increasing climatic and land-use pressures.