Request > Impacts of green and blue space on mental health

The Eklipse Expert Working Group (EWG) reports on the beneficial effects of green and blue spaces on human mental health and well-being, highlight the importance of these spaces’ types and characteristics, and the need for more, targeted research on their effects.

Blue spaces:

The EWG identified the beneficial effects of visits to and experience blue space on human mental health and well-being. These effects are most evident for coastal areas. Qualitative studies have provided insights into blue spaces’ experiential characteristics, which would undoubtedly guide future research, such as the unique dynamic and fluid characteristic of water and the sense of visually open space. Overall the EWG reported that this is a relatively young research field. More high-quality research is necessary, including focusing on a broader range of blue space (particularly inland water) types, blue space characteristics, as well as geographical locations (especially beyond the United Kingdom).

Some of the insights of the analysis show that:

• The majority of the reviewed studies comes from the United Kingdom (fourteen of the twenty-six studies).
• Participant numbers ranged from eleven to an entire population. They included the elderly, children, representative panel data, convenience samples, and mentally distressed people.
• Most studies investigated the effects of blue space on affective outcomes, well-being, life satisfaction, (recalled) restoration, general mental health problems, and problematic behaviour.
• Coastal areas showed benefits across all three study categories (i.e., experimental, cross-sectional and longitudinal, and qualitative). Likewise, studies looking at direct effects of coastal exposure, as opposed to just coastal availability or proximity, showed, in general, more consistently positive results on mental health.
• Few studies investigated inland water exposure, looking at either a river, a canal, a wetland, or the percentage of freshwater around the residence.
• Affect, and affective disorders showed the most pronounced effects across blue space categories. Qualitative studies pointed towards unique and beneficial blue spaces characteristics, including the water’s space and fluidity’s visual openness.

Ultimately, the systematic review outcomes signal the need to look beyond more availability and proximity of blue spaces to actual exposure and people’s experiences in blue spaces.

Green spaces:

The EWG review showed a beneficial relationship between green space and mental health for most types of green space. However, comparisons between different green space types have revealed heterogeneity in outcomes that point at potential underlying pathways that deserve further attention. Highlighting two main avenues for future research: a better assessment of the actual exposure and the role of individual experiences within specific green spaces. Gaining knowledge on how actual exposure to – and experience with – specific natural features can improve and maintain mental health. Overall, enhancing the understanding of which types, characteristics, and variety of green space are required to tailor urban green space design to increasingly vulnerable urban communities’ specific needs and preferences to face increased urbanisation and climate change.

Some of the insights of the analysis show that:

• The studies included in the review were highly heterogeneous in terms of objectives, theoretical frameworks, covariate data, target population, and research methods.
• Other studies point out this diversity as a challenge to makes drawing solid conclusions.
• However, the EWG encounter the same challenge. This diversity in outcomes and user characteristics may not necessarily be a weakness but, instead, a prerequisite for understanding how precisely different green space types and characteristics influence mental health and well-being.
• Another way to purposefully address this heterogeneity is by having a larger contribution from longitudinal studies. Moreover, integrating it in the research methodology by enabling, for instance, a direct comparison not only between different green space types and characteristics, but also between other users (e.g., age, mental health status), various activities (e.g., active versus passive activities), different locations (geographical locations, or in areas with varying densities of the population), or different seasons.

Impact in Policy

Science for Environment Policy (2021) The solution is in nature. Future Brief 24. Brief produced for the European Commission DG Environment. Bristol: Science Communication Unit, UWE Bristol (link)

The impact of the quality of the environment on human health is well described and increasingly taken into account for urban and peri-urban design and policies; however, this is not the case for the impact of biodiversity on mental health and well-being.

Biodiversity may have a great impact on our well-being and mental health. A systematic review of the health and well-being benefits of biodiverse environments has been published in the Journal of Toxicology and Environmental Health (Lovell et al. 2014).  It shows that a biodiverse nature has positive effects on mood and is good for health and that disturbed ecosystems might have a negative effect on human well-being. Bowler et al. (2010) show further evidence of the added benefits to health of exposure to natural environments by conducting a systematic review that compares health or well-being measurements in natural and built environments; however, this review did not explicitly mention biodiversity as such. In 2010, a study of the Faculty of Public Health showed that green spaces can lower the incidence of hyperactivity or depression and that, conversely, people without access to green spaces are more likely to develop stress or anger-again, without explicitly referring to biodiversity (Faculty of Public Health, 2010; Gidlofgunnarson, Ohrstrom, 2007). The importance of natural elements and their impact on mental health can be demonstrated in initiatives such as developing therapeutic gardens aiming to help Alzheimer patients. These studies suggest that there may be some evidence available to enable the design of green spaces to benefit human mental health and mental well-being.

Timeline

• Date request received:  September 2016
• Date of Experts Working Group kick-off meeting: 04/07/2017
• Call for Knowledge: March–April 2017
• Call for Experts: September-October 2017
• Date of experts selection: November 2017
• Date of the online EWG kick-off meeting: November 2017
• Date of the first meeting with the requesters and EKLIPSE KCB and methods experts: March–April 2017
• Finalisation: June 2020

In September 2016, a request was received by Expert Working Group Biodiversity & Health, 3rd National Action Plan on Health and Environment (PNSE3) – Ministry in charge of the Environment (MTES), France, and the World Health Organization (WHO).

This request aims to provide recommendations regarding the design, management, and creation of natural spaces in urban or suburban areas to promote urban inhabitants’ mental health.

Scoping phase

Initially, the requester suggested providing the current knowledge of green spaces’ effects on mental health and physical health. Based on the discussion results between the KCB, the requesters, and the Call for Knowledge (CfK) carried out on April-May 2017. It was agreed to refine the request question to target mental health and psychological well-being and omit physical health (unless linked to mental health in existing research). Psychological disorders were also included in the request’s scope, but indoor greenness (houses, workplaces) would not be considered. The requester has a specific interest in positive impacts to generate recommendations for designing and managing green and blue spaces in cities or nearby neighbourhoods and initially required a systematic review approach.

The CfK specifically resulted in the identification of 6 reviews, 18 articles and about 30 other references provided by experts through the KNOCK Forum. Based on the scoping process and the Call for Knowledge, a Document of Work (DoW) was compiled.

Answering the request

Selection of an Expert Working Group (see above)

To answer this request, Eklipse sent out a Call for Expertise (CfE) and selected 11 experts in November 2017. These experts covered a broad range of expertise, gender and geographical representation to form the Eklipse Expert Working Group (EWG).

The next step was for the Expert Working Group to develop a methodological protocol based on the DoW, including the scientific aspect of a thorough literature search and possible appraisal. From the identified methods, the expert working group decided on performing a systematic review that will follow the following steps:

1) Eligibility criteria for the articles will be formulated
2) A systematic search strategy will be employed to yield relevant articles
3) Meta-data will be extracted and coded for each eligible study
4) Each study will be critically appraised
5) A narrative and descriptive synthesis will be performed
6) Outcomes of the synthesis will be discussed

Methods Protocol

During the scoping process, the EKLIPSE Methods Expert Group (MEG) and the Knowledge Coordination Body (KCB) Health group discussed potential knowledge synthesis methods, which can be applied for this request. Building on the discussions and materials prepared by the EKLIPSE MEG, the following methods were suggested for the different steps of the request:

• Cochrane-style systematic review
• Solution scanning, meta-analysis
• Rapid evidence assessment
• Causal Chain Analysis
• Systematic review

After analysing the available knowledge and other elements like the purpose of the question, time and resources available, consequences and controversies, among others (to have more information on methods criteria section, please follow this link), the EWG support by the MEG and considering the open consultation on the methods protocol decided to perform a systematic review. The systematic review allowed the group to analyse the scientific literature that focused on the influence of type and characteristics of green and blue spaces concerning mental health and wellbeing benefits in cities and sub-urban areas in an interdisciplinary way. For practical reasons, the EWG decided to perform two separate reviews: blue and other for green spaces.

Finalisation

The draft report developed by the expert working group to answer the question of “which types and components of urban and peri-urban blue spaces have a significant impact on human mental health and mental well-being” was released for external review (22nd January 2020-28th of February 2020). The second systematic review draft to understand “which types and components of urban and peri-urban green spaces have a significant impact on human mental health and mental well-being” was released in summer 2020. The EWG has integrated the comments from these processes, and the final reports are publically available.