Nature-based, technological and social solutions can improve cities (Source: The Lancet)

Authors: Alessandro Ossola and Michelle Leishman, September 24th, 2021

Nature-Based Solutions (NBSs) are a new approach to greening cities that seeks the integration among natural, technical and human elements to achieve specific benefits, better performance and increased resilience. The integration of these elements can increase the effectiveness of urban greening interventions, for instance when monitoring technology (e.g., soil moisture sensing) is coupled with adaptive and proactive management (e.g., preventative irrigation prior to a heatwave). While NBSs are still in their infancy in Australia (Frantzeskaki et al., 2021; Ossola & Lin, 2021), these solutions offer a new, integrated and more sustainable way to manage urban plantings and urban greening.

Designed by nature and powered by technology and people

Compared to natural landscapes, plants live in cities among infrastructure, buildings and utilities as well as among people and our decisions. Because of this, urban plants can “interact” with (and sometimes benefit from) the presence of built and human factors in cities. Think about how the simple shade of your house can create a completely different microclimate and habitat opportunities for different plant species with different traits (e.g., shade- and part-shade tolerant vs full-sun species).

By embracing this concept to the fullest, we can imagine that nature-based solutions can be designed and planned to work alongside urban technologies and people. For instance, new scientific evidence suggests that solar panels installed among vegetated areas can have significantly increased energy output compared to those installed in non-vegetated areas, due to reduced peak temperatures and hence improved efficiency (Fig. 1). Similarly, stewardship programs involving residents and home-owners can ensure street plantings are taken care of and irrigated during periods of extreme heat and drought (Moskell et al., 2016).

Because of this, we can more creatively think and design urban plantings where the interactions between plants and other organisms, as well as technology and people, can ensure greater resilience, particularly when considering the looming challenges from climate change. Full integration of these factors can maximize our chances of success of urban plantings while reducing costs and risks of failure.

Figure 1: Rotating solar panels on the Sydney’s Coal Loader green roof are used to protect both plants and people from heat as well as to produce renewable energy (Image: Kirsty Beilharz). Scientific evidence suggests that energy production of solar panels surrounded by vegetation is higher due to reduced air temperatures that increase panel efficiency.

PLANTS + TECH + PEOPLE = A recipe for success

For Nature-Based Solutions to be successful several guiding principles should be considered based on your local context and situation.

Technology changes fast. Fueled by a drive to innovate and perfect, most technologies arise, mature and are replaced by something new. When incorporating technical features into NBS, we need to ensure that these can match the useful life expectancy of a NBS intervention. Think how many substrates, media, cells, etc., have been marketed in the last few years. Once one piece of technology is incorporated into a NBS, these must work together for the longest period of time to ensure environmental and economy sustainability. While predicting what the next technology will be is near to impossible (remember you did not have a mobile phone 20 years ago), technological elements that are reliable, serviceable, redundant and scalable, can often offer the best bang for your buck!
People change their minds. When considering how to include people and communities in NBS programs, careful consideration must be given to the fact that often these might take months and years to be implemented, only to fade off in a matter of weeks due to lack of interest, reduced engagement, barriers to stewardship and much more. As such, rather than starting with a widespread and unrealistic program, try creating something small and scalable that can be flexibly adjusted as new opportunities, skills, talents and interests join the quest. Often finding community leaders, industry champions and allies early on can make the difference between a successful long-term program with high retention and something that doesn’t last the distance.
Nature is still a mystery. Like us, nature often does not behave as expected. Sometimes we simply can’t understand why a plant died after all our care and attention. Let’s face it, we still know little about the many wonders of the natural word and why plants and animals do what they do. This is why our WPW researchers spend their lives trying to better understand the complexities of nature and what these can tell us about our beloved plants. If you stay silent you might hear some leaves whispering to one of our eager scientist!
Build flexibility. You surely remember the old adage ‘one size does not fit all’. Also, what works in one place might completely fail in another. Because of the ever-changing nature of cities, flexible rather than static solutions are increasingly needed to keep up with the unstoppable pace of urban change, development and progress. Can you imagine flexible solutions that can solve not one, but multiple problems at the same time? What about a water-sensitive design feature that couples stormwater prevention during flooding as well as evaporative cooling during a summer heatwave? Modular Lego-like approaches work well with plants as we can play around with a great diversity of species, cultivars, hybrids, etc. By using modular approaches, you can introduce flexibility and increase the safety margins of your nature-based solutions.
Plan A, B, C and of course Z. As crazy as it sounds, when planning something new, firstly try to envision how this could fail. Real innovators and disruptors often flip the concept of “success” around, by trying to fail the ideas on purpose to identify weak points, flaws and mitigation strategies. This approach can generate a much greater knowledge of the urban system you are managing, as well as inform do’s and don’ts critical to ensure long-term success of NBS and other solutions. By embracing and not rejecting failure we can design for sequential adjustments and corrections needed to reach sustainable outcomes that streamline management and minimize costs.

REFERENCES

Frantzeskaki, N., Ossola, A., Bush, J., 2021. Nature-based solutions for changing urban landscapes: Lessons from Australia. Urban Forestry and Urban Greening (in press).

Lin, B., Ossola, A., Ripple, W., et al., 2021. Integrating solutions to adapt cities for climate change. The Lancet Planetary Health, 5(7): e479–e486. https://doi.org/10.1016/S2542-5196(21)00135-2

Moskell, C., Bassuk, N., Allred, S., MacRae, P., 2016. Engaging residents in street tree stewardship: results of a tree watering outreach intervention. Arboriculture & Urban Forestry, 42(5): 301-317. https://www.cabdirect.org/cabdirect/abstract/20173347298

Ossola, A., Lin, B., 2021. Making Nature-Based Solutions “climate-ready” for the 50°C world. Environmental Science and Policy, 123: 151-159. https://doi.org/10.1016/j.envsci.2021.05.026

Resources

What tree growers need from you

How to successfully establish your new trees

Water Sensitive Urban Design

Planting nature-based solutions

What can we learn from natural ecosystems?