Polycentric governance and stakeholder participation in natural resource management have potential benefits for both human and environmental well-being. Researchers and decision-makers have attempted to conceptualise the ecological, social and political potential of such semi-formal approaches to urban green space management. However, few studies have quantified the actual benefits in terms of biodiversity and associated ecosystem service provision, or the factors that mediate levels of participation.The links between biodiversity potential, site access and user participation were explored in a case study comprising ten established examples of organised social-ecological initiatives in the inner-city area of Greater Manchester. At the micro-scale, the case study quantified the levels of community involvement (measured in volunteer hours month¯¹) in local green commons and the biodiversity potential (assessed using floristic and structural diversity as a surrogate) of the ten sites. Descriptive analysis identified that site spatial and design characteristics affected all three measures and subsequent correlational analyses revealed a high degree of synergy between site use and biodiversity.

Common approaches to mapping green infrastructure in urbanised landscapes invariably focus on measures of land use or land cover and associated functional or physical traits. However, such onedimensional perspectives do not accurately capture the character and complexity of the landscapes in which urban inhabitants live. The new approach presented in this paper demonstrates how open-source, high spatial and temporal resolution data with global coverage can be used to measure and represent the landscape qualities of urban environments. Through going beyond simple metrics of quantity, such as percentage green and blue cover, it is now possible to explore the extent to which landscape quality helps to unpick the mixed evidence presented in the literature on the benefits of urban nature to human well-being. Here we present a landscape approach, employing remote sensing, GIS and data reduction techniques to map urban green infrastructure elements in a large U.K. city region. Comparison with existing urban datasets demonstrates considerable improvement in terms of coverage and thematic detail. The characterisation of landscapes, using census tracts as spatial units, and subsequent exploration of associations with social-ecological attributes highlights the further detail that can be uncovered by the approach. For example, eight urban landscape types identified for the case study city exhibited associations with distinct socioeconomic conditions accountable not only to quantities but also qualities of green and blue space. The identification of individual landscape features through simultaneous measures of land use and land cover demonstrated unique and significant associations between the former and indicators of human health and ecological condition. The approach may therefore provide a promising basis for developing further insight into processes and characteristics that affect human health and well-being in urban areas, both in the United Kingdom and beyond.

Studies have repeatedly affirmed the positive links between human and environmental health but few have sufficiently addressed the complexity brought about by the range of urbanity, population and both green space and domestic gardens cover associated human settlements. With the global population increasingly residing in cities, the relevance of urbanisation, local population and discrete types of green space provision on measures of health, remains a research imperative. To explore this complexity, a series of regression models were employed to quantify the mitigation of local health deprivation by green space and domestic gardens, across a four-stage rural-urban gradient, controlling for household income and local population. The population-standardised quantification of green space provision offered greater interpretive power than did a simple measure of land cover density. Domestic gardens, of the two green land-cover types, provided the most convincing mitigating effect on health deprivation. The findings call for increased acknowledgement of urban gardens in local health promotion, and a closer consideration of local population in planning green space provision and management.

This article provides a perspective on nature-based solutions. First, the argument is developed that nature-based solutions integrate social and ecological systems. Then, theoretical considerations relating to relational values, multifunctionality, transdisciplinarity, and polycentric governance are briefly outlined. Finally, a conceptual model of the social–ecological system of nature-based solutions is synthesised and presented. This conceptual model comprehensively defines the social and ecological external and internal systems that make up nature-based solutions, and identifies theoretical considerations that need to be addressed at different stages of their planning and implementation The model bridges the normative gaps of existing nature-based solution frameworks and could be used for consistent, comprehensive, and transferable comparisons internationally. The theoretical considerations addressed in this article inform practitioners, policymakers, and researchers about the essential components of nature-based solutions. The conceptual model can facilitate the identification of social and ecological interconnections within nature-based solutions and the range of stakeholders and disciplines involved.

Background: There is a growing body of literature supporting positive associations between natural environments and better health. The type, quality and quantity of green and blue space ('green-space') in proximity to the home might be particularly important for less mobile populations, such as for some older people. However, considerations of measurement and definition of green-space, beyond single aggregated metrics, are rare. This constitutes a major source of uncertainty in current understanding of public health benefits derived from natural environments. We aimed to improve our understanding of how such benefits are conferred to different demographic groups through a comprehensive evaluation of the physical and spatial characteristics of urban green infrastructure. Methods: We employed a green infrastructure (GI) approach combining a high-resolution spatial dataset of landcover and function with area-level demographic and socioeconomic data. This allowed for a comprehensive characterization of a densely populated, polycentric city-region. We produced multiple GI attributes including, for example, urban vegetation health. We used a series of step-wise multi-level regression analyses to test associations between population chronic morbidity and the functional, physical and spatial components of GI across an urban socio-demographic gradient. Results: GI attributes demonstrated associations with health in all socio-demographic contexts even where associations between health and overall green cover were non-significant. Associations varied by urban sociodemographic group. For areas characterised by having higher proportions of older people ('older neighbourhoods'), associations with better health were exhibited by land-cover diversity, informal greenery and patch size in high income areas and by proximity to public parks and recreation land in low income areas. Quality of GI was a significant predictor of good health in areas of low income and low GI cover. Proximity of publicly accessible GI was also significant. Conclusions: The influence of urban GI on population health is mediated by green-space form, quantity, accessibility, and vegetation health. People in urban neighbourhoods that are characterised by lower income and older age populations are disproportionately healthy if their neighbourhoods contain accessible, good quality public green-space. This has implications for strategies to decrease health inequalities and inform international initiatives, such as the World Health Organisation's Age-Friendly Cities programme.