Blue and green make grey work better: how blue and green infrastructure can improve equity of ecosystem services in urban areas
Andersson, E. J. Langemeyer, S. Borgström, T. McPhearson, D. Haase, J. Kronenberg, D.N. Barton, M. Davis, S. Naumann, L. Röschel, F. Baró. 2019. Enabling green and blue infrastructure to improve contributions to human well-being and equity in urban systems. BioScience 69(7):566-574. https://doi.org/10.1093/biosci/biz058
Ecosystem services are something humans benefit from greatly, even when we are not aware of them! Ecosystem services are defined as the benefits provided by the natural environment to humans from healthy ecosystems. People living in urban areas may feel more disconnected to nature than their neighbors in more rural areas, but ecosystem services can and do exist even in densely populated urban centers. Exploring how to make these ecosystem services work efficiently and serve everyone in an equitable way has been challenging for ecologists and urban planners alike. However, as cities are becoming more prepared to tackle climate change and move in a more sustainable direction, there have been a lot of advances in how to improve the diversity and quantity of ecosystem services available.
Green and Blue Infrastructure
In this article, Erik Andersson and his team of energy consultants work to understand how ecosystem services can be turned into equitable benefits for all urban residents, with a particular focus on the benefits from urban green and blue infrastructure (GBI). Green infrastructure are urban installments of vegetation or soils that work to mimic and restore natural processes. For example, water management from pervious surfaces like rain gardens and shade from trees and urban parks. Blue infrastructure refers to the incorporation of water elements, like rivers or canals, into urban areas to utilize the ecosystem services provided by water to residents in urban spaces. The authors remind us, historically in urban planning and policy making, infrastructural networks, such as green, blue, and grey (the built infrastructures), were treated separately. Today urban planners are transitioning infrastructure management to be more comprehensive and focus on incorporating GBI because of the benefits to urban residents. Green and blue spaces in and around cities can serve urban residents in a variety of ways, including addressing critical issues such as “temperature increases, poor environmental quality, and limited social inclusion.” GBI also holds promise for helping cities to tackle “broader urban sustainability challenges, such as climate change impacts, needs for outdoor recreation, and spaces for social activity.” A comprehensive approach to managing urban infrastructure, including grey, green, and blue, that focuses on the interactions between different infrastructure elements is important for moving cities in a sustainable and climate-change ready direction. However, the distribution of benefits from managing infrastructure more comprehensively differ spatially across neighborhoods. A common example of this is accessibility to transportation and mobility or having less updated infrastructure in low socioeconomic neighborhoods.
GBI such as street trees, parks, gardens, waterways, and wetlands all make residents of urban areas feel more connected to nature. However, it is important to realize that the distribution and accessibility of these benefits and ecosystem services are not equal. As an example of this inequality is highlighted in the un-even tree canopy cover in many cities. Neighborhoods with lower socioeconomic status commonly have fewer street trees and communities in these neighborhoods cannot benefit from the ecosystem services provided by street trees, such as additional shade and cleaner air. Addressing these inequities is challenging. It is difficult to overcome the barriers that exist exacerbating these inequities. Some of these barriers include urban development, institutional arrangements, historical legacies, and social inequities and structural racism. The authors stress the importance of addressing inequities through a systemic and context-sensitive approach that improves the flow and more equitable distribution of ecosystem services.
Infrastructure, Institutions, and Perceptions
The authors focus their study on three key factors to help in this aim: infrastructure, institutions, and perceptions. These three factors serve as interconnected systems in urban areas that contribute to the flow of ecosystem services. These factors work to “mediate or hinder the flow of benefits” to urban residents and “therefore affect the distribution of benefits” across the population. Infrastructure acts as the networks, layouts, and intersections that make up the built urban environment, and include both green and blue infrastructure. Institutions include the institutional arrangement in cities, comprising of ownership, user rights, and policy decisions. Consumers do hold some power over institutions. Making sustainable and educated choices in what we consume and who we choose as elected officials help to hold institutions accountable for treating the environment with respect. And lastly, perceptions in urban areas, include the understanding and preferences of beneficiaries, and the numerous social and cultural factors that influence how people have access to commodities in urban areas.
When thinking about infrastructures and all of the factors that influence the accessibility to these benefits throughout the urban population, it is important to remember how inter-connected different infrastructure elements are. In fact, in order to understand an individual infrastructure element, such a green or blue infrastructure, one must understand how it is connected to and influenced by other infrastructure elements. Additionally, more vulnerable communities, tend to bear a disproportional burden of environmental degradation. In order to achieve a more equitable and sustainable city, with equal access to the ecosystem services of GBI, urban planners need to be able to locate and distinctly address areas of need or demand for these services at the community level. An improved understanding of how GBI and ecosystem services are delivered to the entirety of the urban population will help to make these services more accessible to all residents.
The authors conclude that in order to deliver the full potential of ecosystem services from GBI to all urban residents, we must address issues within the wider urban system. Approaching urban planning from a trans-disciplinary perspective will highlight the quality and accessibility of ecosystem services across the population. The authors stress that there is not one framework or standard method that will work across all urban areas, instead a context-specific approach must be taken to develop a relevant solution that will work for the community at hand. This baseline approach should be used to position and align a wide variety of stakeholders in a common goal of helping to make ecosystem services from GBI in urban areas accessible to all.