Informal Urban Green Space: Residents' Perception, Use, and Management Preferences across Four Major Japanese Shrinking Cities
Urban residents' health depends on green infrastructure to cope with climate change. Shrinking cities could utilize vacant land to provide more green space, but declining tax revenues preclude new park development-a situation pronounced in Japan, where some cities are projected to shrink by over ten percent, but lack green space. Could informal urban green spaces (IGS; vacant lots, street verges, brownfields etc.) supplement parks in shrinking cities? This study analyzes residents' perception,
... se, and management preferences (management goals, approaches to participatory management, willingness to participate) for IGS using a large, representative online survey (n = 1000) across four major shrinking Japanese cities: Sapporo, Nagano, Kyoto and Kitakyushu. Results show that residents saw IGS as a common element of the urban landscape and their daily lives, but their evaluation was mixed. Recreation and urban agriculture were preferred to redevelopment and non-management. For participative management, residents saw a need for the city administration to mediate usage and liability, and expected an improved appearance, but emphasized the need for financial and non-financial support. A small but significant minority (~10%) were willing to participate in management activities. On this basis, eight principles for participatory informal green space planning are proposed. Land 2017, 6, 59 2 of 24 research-we still know little about what residents in Japan think of informal urban green spaces such as vacant lots, street verges or brownfields, let alone participative management approaches. To fill this gap, this paper seeks to provide some insight by analyzing how residents in four major shrinking Japanese cities perceive and use informal urban green spaces, what management goals and approaches they prefer, and how willing they are to participate in managing such spaces. Japanese cities are facing a major demographic challenge with consequences for urban land and green space management. This makes the country a useful object of study, because similar demographic trends are expected in other countries such as South Korea or China as the population peaks and the economy enters the post-growth stage. Until 2040, many are projected to experience both rapid aging and population decline, with some likely to lose over 10% of their total population  . The major effects of this trend are fourfold. First, the cumulative effects of aging and depopulation are eroding cities' tax base, which in turn forces them to balance expenses for maintaining green spaces with competing demands such as aging water infrastructure. This puts budgets for green space under scrutiny and leaves them at risk of being cut, even though many Japanese cities already fail to provide the 10 m 2 of park area per person set in governmental standards  . Second, the number of both vacant houses and vacant lots are increasing , a trend that will likely accelerate as population decline intensifies. While this process could be seen as an opportunity for municipalities to buy land at a moderate price to increase public green space, their financial situation makes this difficult. In fact, strategic park planning in Japan has recently focused on protecting current levels of green space rather than expanding them, as cities are struggling to cover maintenance costs for parks built during the decades of high population and economic growth. Third, as the population demographics change, so do people's green space and nature needs  . Recent years have seen a strong demand for recreational urban agriculture, with long waiting lists for community garden parcels being a common occurrence. While some cities such as Yokohama have started retrofitting parks with areas for growing vegetables, such initiatives are still rare. Finally, Japanese cities will need to invest heavily into green infrastructure to adapt to and mitigate the effects of rising global temperatures due to climate change    . The cities' aging population is particular at risk from heat-related health problems, making this also an urgent issue of public health. These demographic transition-related major effects have led researchers to investigate the potential of non-traditional green spaces  . Recent research has shown that both in Japan and abroad, informal urban green spaces (IGS) such as vacant lots, street verges, brownfields, power line corridors and waterside spaces can make up about 5% of urban land  . Moreover, residents are already using these spaces for recreation, both as adults and children [23, 25] . However, not all residents evaluate these spaces favorably as they are largely unmanaged. In particular, the aesthetics of wild nature do not necessarily directly translate from a Western to a Japanese cultural context  , where many residents prefer to see a human touch as evidence of human care and attention for a space. Against an international background of residents using and re-using-often spontaneously-land considered derelict or unwanted by conventional urban planning    , researchers have thus called for exploring ways informal green spaces in shrinking Japanese cities could be managed by the local community using participatory approaches  . However, a number of questions about participatory IGS management in Japan remain unanswered. Addressing the following gaps in the literature will support municipalities in planning and implementing such management approaches, with the intention of contributing to residents' wellbeing. Under what circumstances and in what form might participatory IGS management be feasible in shrinking Japanese cities? To answer these questions, two major gaps in the existing literature need to be addressed. First, existing exploratory studies [23, 25] on how residents in Japan perceive, use, and evaluate IGS have been limited in scope (single city) and sample size (<200), were not representative and, as mail-back surveys, may have suffered from bias where only residents interested in the topic responded. Second, we know little about how residents think of participatory IGS management, from their preferred management goals and approaches to acceptable levels and forms of participation. Land 2017, 6, 59 3 of 24 This paper thus focuses on the following questions: (1) how do residents perceive, use and evaluate IGS across major shrinking Japanese cities; (2) what management goals do residents prefer for IGS; (3) how do residents think about different ways, approaches and circumstances in participatory IGS management; and (4) how willing are residents to engage in participatory IGS management? Addressing these questions is important, because the resulting findings and insights may inform urban planning, climate adaptation and participatory management in post-growth industrialized countries, using Japan as a case where depopulation is most advanced. The study thus contributes to the local (site-specific), national and international discourse.