While the term “ecosystem services” may sound like a corporate antithesis to the course of natural order, it is actually an umbrella term for the ways in which the human experience is favorably altered and enhanced by the environment. Ecosystem services are therefore an important factor in creating cities which provide the maximum benefit to their residents with the minimal harm to their environment.
Aiming to find out how city planning can affect the provision of these ecosystem services, a new study published in Frontiers in Ecology and Environment by researchers at the University of Exeter's Environment and Sustainability Institute and Hokkaido University's Division of Environmental Resources evaluates the repercussions of rapid and fragmented urbanization and the possible detriment to ecosystem services and human well-being. In particular, the study is concerned with approaches to land-use and the outcomes they yield on the environment. Studied are two opposing tactics: a “land-sharing,” sprawl model (think Atlanta or Houston), or “land-sparing,” tight-knit urbanism (think New York or Tokyo).
Based on the UN’s Millennium Ecosystem Assessment, created to analyze the impact of our actions on ecosystems and their benefits to us, ecosystem services are grouped into four major categories: provisioning, regulating, cultural and supporting services. The first two are broken up into items we consume: food, water, fiber, wood, and medicine, and the systems that produce these items: pollination, decomposition, water purification, irrigation and carbon storage. The latter are less specific, but measure how ecosystems impact our culture, ideas, and recreation, and the services that support the ecologies, such as photosynthesis, nutrient creation, and water cycles.
The Exeter/Hokkaido study looks at carbon storage, water infiltration, human well-being, agricultural production, pollination, pest control, noise reduction, air purification, and temperature regulation. By studying these nine services, they come to a familiar consensus: that low-lying structures and sprawl (land sharing) are economically and ecologically faulted, while on the other hand compact, vertical urbanism, with large areas of adjacent green space (land sparing) are beneficial. However, they do uncover a single, conflicting service among these nine, finding that human well-being is more greatly benefitted by a sprawl system. Because of this, the study concludes that “for humans to get the most benefit, combining this [land sparing] approach with greening of built land using street trees and some small parks and gardens is the best method,” explains lead author Dr Iain Stott.
While there have been significant studies on the science of urbanism and ecology by organizations including the International Finance Corporation, the US Council on Environmental Quality, and Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES), there has yet to be a critical-mass adoption of such concerns in architectural practices, but there is a pressing imperative for it. In order for this to occur, ecosystem services must become more widely known or understood as an idea - or perhaps more cleverly packaged into a branded concept, similar to the way that leadership in energy and environmental design has been successfully marketed as the LEED standard in green buildings.
While it can be easy to dismiss measures that will add new costs and protocols to building design, especially by those footing the bill, solutions that benefit ecosystem services need not be overly expensive, and many tools to implement such changes already exist. The Exeter/Hokkaido study suggests street plantings, permeable roads and pavements, green walls and green roofs as several small tools which can create large positive benefits to ecosystem services, and even break down the simplified “land sharing vs land sparing" dichotomy.
The recently completed renovation to the Jacob K Javits Convention Center in New York is a specific example of how ecology and design can be mutually beneficial to economy and ecology. Earning the title of second largest green roof in North America, the Javits Center canopy can now absorb rainwater, a boon to the city’s sewer system, and is providing a new ecology for a variety of bird species. It will soon also host bee colonies for honey production. In tandem, the building’s new facade of fritted glass panels, of primary advantage to birds, has also helped moderate the building’s temperature.
The evidence shows that design choices that benefit ecosystem services are congruous with our own best interests, a point mirrored by the Exeter/Hokkaido study and others advocating for wider adoption of design practices that consider these imperatives. Though these practices may seem like common sense to those living in cities or monitoring the success of land sharing projects like New York’s High Line or land sparing ventures like London's Queen Elizabeth Olympic Park and Jeanne Gang’s newly unveiled park on Chicago’s Northerly Island, future success hinges on these practices being the rule and not the exception.
Learn more about the study by the University of Exeter and Hokkaido University, titled "Land sparing is crucial for urban ecosystem services," here.