Within the Terrascope 2024 project, one avenue for addressing waning biodiversity is adaptive landscaping. Solutions related to this urban planning concept will center around repurposing abandoned places in cities with the goal of expanding pollinator habitats and improving wastewater management to nurture the populations of insects, birds, plants, and aquatic species affected by cities.
Adaptive building and landscaping is a broad concept that many U.S. cities have experimented with to transform industrial wastelands into lush community spaces for their residents. The process of building according to adaptive landscaping usually fits the following criteria: attracts insects and other pollinators due to thoughtful incorporation of plants, focuses on removing toxins from soil and water, is less invasive regarding human infrastructure, supports to recreational activities, and supplements economic activity and cultural traditions.
A case study in successful adaptive landscaping is Gas Works Park in Seattle, a factory-turned-green-space that was realized after intensive efforts to remove pollutants from the soil were undertaken so a healthy natural habitat was reclaimed.
When considering places with potential for rebuilding with a greener design, Terrascope 2024 takes “abandoned” to describe any area (building, lot, etc.) that either belongs to the city or does not have another viable owner and is currently in disuse. For abandoned buildings, taxes are not paid and buildings are not legally occupied. A “distressed” building has similar potential for repurposing, being both unoccupied and dilapidated, but it may or may not have outstanding taxes. Both types of unmaintained infrastructure are part of the solution plan for Terrascope 2024.
The Birds and The Bees (Plus Plants)
When modeling the potential solutions to declining biodiversity by way of adaptive landscaping, Terrascope 2024 will use success metrics for pollinators and species specific to Massachusetts because the solution will use Boston as the model. There are three endangered species of bees in Massachusetts whose recovery would provide great economic and health benefits to the city and are therefore important reference points for measuring recovery of biodiversity: Anthophora walshii, Bombus pensylvanicus, Bombus terricola. Pollinators in general have an expected benefit of $30 billion in the US per year, and wild types like those previously mentioned are estimated to account for $4 billion of that.
Given that bees contribute so greatly, it is alarming that their colonies have seen a decrease in number as great as 8% from year to year. There are many threats to their population size, including the mysterious colony collapse disorder, overwintering mortality, and pesticide use in agricultural areas. A study in Oklahoma found that there was no statistically significant difference between the number of bees found in rural areas and those found in urban areas, suggesting that urban habitats can play a role in the resurgence of bee populations, where they are safe at least from the effects of pesticides.
There are also 35 threatened or endangered moth and butterfly species and 30 such bird species. Gauging the size of these populations, in comparison to these populations in past decades and in comparison to these populations in other cities, will serve as measurable indicators for determining the success of a solution proposal.
Plant biodiversity can be tracked the same way, intended to grow in complement to the pollinators’ presence as building plans will feature reintroduction of diverse native plant species suffering dwindling numbers. Other indicators that will be adopted by this group, inspired by a 2017 plan by the Massachusetts state government for improving the prospects of pollinators, will be to increase the acreage of pollinator habitat within the city and to reduce colony overwintering mortality rate to 15% or lower. Lowering the mortality rate is important to maintaining population size. These goals pertain to insects in particular.
The distinction between insects which provide economic benefits to humans and those considered “pests” is also important to make. Insect species and arthropods comprise most of the Earth’s species, occupy diverse niches, and provide food and medical benefits for ecosystems. Because of all of insects’ functions and connections to other species in the ecosystem, their richness, or the quantity of different species, impacts the state of the ecosystem, and any changes in their richness can significantly change the state of the ecosystem. However, there is not necessarily a human interest to promote the population of certain insects like mosquitoes or roaches—the “pests”.
Pests are usually defined as species that threaten human needs but which may still play important ecological roles, like cockroaches that help recycle waste. While the project will not focus on nurturing the population of these pest species, part of the designation of “pest” is that such species require little help from humans to maintain a burgeoning population. The project will instead focus on altering industrial spaces so that pests which live off of urban waste may thrive but species that require a greater presence of plants may thrive, too.
Specific Biodiversity Metrics
Species evenness has been evaluated as a factor of species richness, and specifically, it is a mathematical function of richness, making it an indicator of both biodiversity and health of an ecosystem. For this reason, evenness rather than richness will be the metric used to gauge success of the Adaptive Building group when it comes to aquatic species.
An example to illustrate the meaning of evenness is as follows: a river with one carp and nine trout is far worse in biodiversity than a river with five carp and five trout, despite having the same number of total individuals and species. The group is considering calculation of evenness according to how “evenness” is generally measured in scientific studies:
In this case, the Shannon Diversity Index is a value that accounts for both abundance of a species and the number of other species present.
A final aspect of the solution is categorizing abandoned places according to their population density and proximity to the city center, and both these factors will dictate the size of infrastructure that could be developed in the area. Neighborhoods located in the less developed parts of a city, including maturing suburbs, usually near the edges and away from urban centers are considered “periphery”. The exact distance radius will not be used as a quantitative metric for designating “center” and “periphery” since this can vary from city to city. Instead, “center” and “periphery” can be more quantitatively defined by measuring the percent of surface area in the region that is impervious to water. This is further explained here. The designation of the abandoned infrastructure as “residential,” “commercial,” “industrial,” or “mixed use” will also influence the possibilities for repurposing based on the city development policies regarding each type.
- Abandoned Land Potential
- Environmental Impact
- Economic Feasibility
- Why It Matters
- Proposed Solution
- Consulting MIT Researchers