Figure 1: Our initial understanding of the actors influencing our topic of urban green spaces, from preliminary research and findings.
The boundary between what is natural and what is urban has always been blurred. This is evident more than ever with the popularization of urban green spaces. The Environmental Protection Agency defines green spaces as “land that is partly or completely covered with grass, trees, shrubs, or other vegetation. Green space includes parks, community gardens, and cemeteries.” (EPA 2015). A lot of research has been done on the benefits of green spaces in developing urban communities. The Portland-based Urban Greenspace Institute claims that, “Our motto, In Livable Cities is Preservation of the Wild, reflects our philosophy that well-designed, nature-rich cities are beautiful, equitable, compact, and ecologically sustainable places to live, thereby reducing urban sprawl across the rural landscape.” (Integrating 2015). There is no doubt that this subject is important to urban centers, but we were left wondering if urban green spaces actually reduce urban sprawl across the urban environment or would push urban sprawl farther. Our framing questions is:
What are the implications of an equitable distribution of land use?
To situate and focus our research on this topic, our focus question is:
How have urban green spaces influenced population development and urban sprawl in Portland?
These questions, although situated in the Portland metropolitan area, can be applied to any developing urban space. The United Nations estimate that 47% of the world’s total population lives in urban areas, and they project this number to rise to 60% within the next fifteen years (Home et al. 2009). The total area of urban land worldwide has increased 58,000 km2 from 1970 to 2000, which is significant because there is thought to be a connection between green spaces and urban land expansion. In addition, the rate of expansion of urban land has been greater than the corresponding population growth (Seto et al. 2011). This global increase of urban sprawl poses various challenges to urban planning as expansive cities take up more land and have higher transportation costs than compact ones. Urban sprawl also is linked to decreased physical activity, increased air pollution and other negative health implications. The driving factors of urban expansion differ greatly between the different regions of the world and even within countries. For example, countries with higher incomes generally have slower rates of urban expansion and a greater link between GDP and expansion. The United States is a bit of an anomaly from this model in that urban land expansion is driven more by population growth than it is in other high income countries. Other factors that affect urban land expansion include land use policy, international capital flow and transportation costs, all of which are incredibly nuanced to each unique urban area.
One of the most important issues with equitable urban land use is gentrification, defined as “rehabilitation of working class and derelict housing and the consequent transformation of an area into a middle class neighborhood” (Atkinson et al. 2004). This is a huge issue for many cities because of the large racial and classist inequalities that result from gentrified neighborhoods, which is relevant because urban green spaces can be a driving factor in the gentrification of a neighborhood. Green spaces may attract wealthier communities and push marginalized communities into other neighborhoods. This is also an increasingly important issue in our modern world as cities around the world experience the effects of globalization on the neighborhood level (Atkinson et al. 2004).
The United Nations has created various models for future population growth and the current prediction is that by 2030 the global population will have reached 8.5 billion people (Home et al. 2009). With the rapid industrial development of the world, along with the already large proportion of its population already living in urban areas, city planning and land-use planning will benefit greatly from learning more about the advantages implications of not only allocating land for green spaces, but also ensuring the equity of that distribution among demographically differing neighborhoods. Because neighborhoods differ so greatly, figuring out what the demographics of a space are will improve the planning of land use. With our research, we hope to map out the demographics of major Portland neighborhoods and compare that to corresponding green spaces in this areas. Along with this, we plan to look out outside research surrounding the conversation of green spaces in other situated areas and see if these green spaces have an impact on the development and growth of these communities.
When managed properly, urban green spaces are capable of providing numerous benefits such as reducing pollution and building community. Increasing green spaces may decrease exposure to air pollution, improve water quality and possibly mitigate climate change (Conway et al. 2010). Local ecosystems will benefit from urban green spaces as healthy streams and increased habitat provide refuge for both local and migratory species (Rodgers and Evans 2007). Green areas also provide much needed space for outdoor recreation, which encourages physical activity and may reduce obesity. Given these benefits one would expect to see green spaces a priority in urban planning. The issue however, lies in limited land in urban areas and conflict of interest over the proper allocation of that land. In densely populated cities such as Los Angeles a dearth of affordable housing has led to a reluctance to convert land to green space (Conway et al. 2010). One proposed solution is greening efforts that make use of available space without tearing down buildings. However, decisions over green space management often lead back to the larger debate of determining the ‘best’ use of limited urban space.
Beginning our research, we looked at the dominant conversation concerning urban green spaces and current research being conducted. To do this, we looked at a variety of 25 different articles, books, and journals concerning urban green spaces that were among the most prominent and accessible resources online. There were several key trends we noticed. First, while we did record a few books and popular articles, the vast majority of resources we found were scholarly journals. This suggests that while urban green spaces are important for a lot of people, the people most interested in them were scholars and researchers. Interested in this, we decided to map where the authors conducted their research, see figure 2.
Figure 2: Cities with Situated Urban Green Space Research and Countries with the highest level of Human Development
Figure 3: Example of Data Collected (2 of 25 sources shown, see appendix 1 for full source list)
All the research shown in the 25 articles we recorded was conducted in North America, Europe, and East Asia. The majority of interest for urban green spaces is in highly developed, already established cities rather than still developing cities. In addition, the majority of research was focused around public health (7 articles), ecology (5 articles), and community (4 articles). This makes sense as these are topics that are generally more critical for already developed cities. This background research was also useful in establishing where the gaps in research are and what regions would most benefit from further research into urban green spaces. India, China and Africa have experienced the greatest rate of urban land expansion from 1970 to 2000, so it is important to note that none of the articles analyzed were situated in Africa or India. This indicates that many of the areas with the most current and pressing interest in urban land development are excluded from the discourse on the green spaces.
The earliest article we found was from 1999. Urban green space is a relatively new topic of discussion with the average article being published around 2010. This shows that it is still a largely unexplored area of research for most of the world. Furthermore, almost all the articles were positive towards urban green spaces, whether that was that they promote outside activity, ecological diversity, community building, or raise property value. Very few were critical of green spaces or mentioned potential problems such as gentrification or its relationship with urban sprawl.