Christopher X J. Jensen
Associate Professor, Pratt Institute

Urban Transect Walks: helping your students see the overlap between ecological and social patterns

Posted 14 Aug 2017 / 0
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This year around, I put most of my impression of the Ecological Society of America annual meeting into a single summary post [link pending]. But one element of the meeting was so valuable that I wanted to highlight it in a separate post. A field trip led by Charlie Nilon and co-facilitated by Paige Warren, Myla Aronson, and George Middendorf seemed worthy of describing on its own.

Based on a Teaching Issues and Experiments in Ecology activity originally published by Charlie and George, this field trip took us across an urban gradient along Portland, Oregon’s North Williams Avenue. We took a bus to North Rosa Parks Way and then walked down Williams Avenue to about NE Fremont Street. Along the way we discussed ways in which students might use such a crosstown walk to study both ecological and social gradients and look for signs of a changing environment. Charlie and George treat such walks as “urban transects”, and as such they can be conducted using the same techniques as any ecological transect might; what you observe might be different than in a “natural” ecosystem, but the approach is the same.

Before the walk, Charlie sent all of us who had signed up for the field trip some background reading materials, including a great history of the Albina neighborhood through which we would walk our transect (“Bleeding Albina: A History of Community Disinvestment, 1940-2000“). Having this reading was crucial, as much of the history of the neighborhoods that we walked has been obscured by more recent changes in the built environment and in the demographics of current residents. As can be observed in so many other “livable cities” across the United States, the process of gentrification is rather rapidly shifting not only Portland’s architecture but also who can afford to live (and who feels welcome) in the city.

Although not all cities have the density and diversity to perform such a transect walk, where you can do it these walks are filled with learning opportunities. There are a variety of ways of performing such an activity, but the simplest way is to walk one direction making informal observations (recording a “natural history” of the transect) and then return conducting a more formal study (testing hypotheses about patterns observed in the “natural history”). We only walked in one direction and we did not have time to actually make any formal observations, but we were introduced to a variety of possible observations that undergraduate students can make on such a walk. These include a variety of conventional ecological measurements (including noise levels, canopy cover, soil temperature and moisture, animal and plant species richness) as well as measurements particular to human-dominated environments (including building density and age, size of lots, presence and absence of sidewalks, density and types of cars).

I started teaching in South Williamsburg, Brooklyn (New York City) in 1994, so I have some sense of how the historical sequence of gentrification unfolds. I have been interested in the process from a variety of angles. As a privileged, white resident of New York City, I have always been acutely aware of my role in the process (and how hard it is not to transform neighborhoods by your presence). As a former public school teacher who served a rather under-privileged population, I can also see gentrification through the eyes of my former students, many of whom probably can no longer afford to live in the neighborhood they used to call home. But there’s also an ecological quality to gentrification, one that reminds me of the process of succession: as one socioeconomic population displaces another, over time that population also has the potential to facilitate the entry of an additional (more privileged) population, perhaps until the neighborhood reaches a “climax” level of affluence. Clearly the analogy between succession and gentrification is rather weak, as human populations from different socioeconomic groups are not the same as biological species. And the last thing that I would want to ever do would be to naturalize the process of gentrification, which I think has serious ethical implications. But can we use ecological tools to better understand the process of gentrification?

Based on my experience with this walk (and other observations that I have made an urban resident), I think that we might be able to.

One thing that was really clear as we walked South on North Williams Avenue was that how a neighborhood shifts has a lot to do with its general infrastructure. At the north end of our transect walk was a neighborhood that was filled with massive, old trees and some very classic old architecture. Here we saw lots of signs of gentrification. The most prominent to me were the total remodels: quite a number of beautifully-designed houses had been exquisitely restored, their yards filled with well-manicured gardens. Often these restored houses stood next to very similar houses that had not been restored, suggesting a neighborhood in the middle of transition towards greater affluence. This north end of North Williams Avenue reminded me of Brooklyn neighborhoods like Park Slope and Clinton Hill, each of which went through a period of economic decline before being “discovered” by more wealthy emigrants attracted to the “good bones” of the classic architecture. If we think about urban neighborhoods successively increasing in population density, one factor that can clearly arrest that succession is the presence of architecture that can be restored to its original, classic condition. It is of course ironic that the appeal of such architecture depends on the overall identity and socioeconomic status of a neighborhood; the history of North Williams Avenue suggests that the displacement of African American residents facilitated the emigration of people with the affluence to “fix up” the old infrastructure. The process of gentrification is rife with such ironies.

Further south along our transect, a different trend was apparent. The most obvious shift was a change in the number of trees: we went from being almost totally shaded to being in open sunlight, suggesting that historically there was a dividing line between these northern and southern portions of North Williams Avenue. The housing changed as well: fairly large yards containing more luxurious houses yielded to much smaller yards containing smaller, more compact houses. And then we began to see the new construction: like all gentrifying cities that I have visited, Portland has its own kind of condominium. While some of these higer-rise buildings are just luxury one-family homes, most are higher-density multi-residence constructions… some of which reach the density level of what I would call an apartment building. Rather rapidly between NE Prescott and NE Skidmore streets, North Williams Avenue becomes a pretty high-density neighborhood, at least by Portland standards.

Although it is not really possible to read the whole building history of the neighborhood on such a walk, it appeared to me that two factors explained why the southern end of North Williams Avenue was experiencing greater densification as it gentrified. The first factor has to do with existing housing stock: it appeared as though the market value of many of the homes on the southern end of our walk was much lower, in part due to the lack of trees but also due to less expensive initial construction and smaller yards. This probably makes it easier for a developer to purchase a series of lots, demolish the existing single-family homes, and build a condominium. It was also pretty clear that zoning played a role: as we walked south, there were clearly more retail and industrial buildings, a common target for conversion to luxury housing. The southern end of North Williams Avenue reminded me of the Brooklyn neighborhoods of Greenpoint and Williamsburg, whose combination of industrial buildings and working-class houses has made it a target for both demolition of the original architecture and conversion to higher-density housing.

In my eyes, economic forces are in some ways like ecological forces. The distribution of resources as well as the historical presence and absence of different populations dictate whether a neighborhood will shift over time. This process can be influenced by deliberated human decisions (such as whether there is redlining in a city, or how zoning is used to foster particular forms of development), but a lot of what happens as neighborhoods gentrify is not planned: it unfolds because there are economic gradients that push some people into neighborhoods and some people out of neighborhoods. And you can see this dynamic unfold in cities, because even good-faith attempts to maintain socioeconomic diversity often can’t hold back the economic tide. Portland is clearly a city that prides itself on being very tolerant of diversity, but like so many other cities this welcoming instinct doesn’t actually translate to diverse communities because many demographic groups are priced out of neighborhoods by the gentrification process. Here’s where this “succession analogy” could be useful: can we use ecological thinking to better understand the factors that allow gentrification to displace previous residents and lower the diversity of city neighborhoods? And if we gain this understanding, could we use it to design better policies aimed at maintaining diversity within neighborhoods?

I realize that my musings, inspired by this great field trip, are probably a bit beyond the scope of an urban transect walk that I might undertake with my students. But in observing how ecological measures like tree cover correlate with urban measures like building density, students can at least be able to make connections between the scientific study of ecology and a sociological understanding of our built urban environments. I think that’s a pretty powerful outcome of this activity!

Many faculty are conducting these crosstown walks; the Global Crosstown Walk Project, organized by UrBioNet, even endeavors to foster the practice across continents! As we move more deeply into the Anthropocene, a geological epoch during which most humans will live in cities, it becomes more and more important that we understand the dynamic ecology of our cities: both in terms of how they accomodate other species (biodiversity) and how they accomodate the diversity of humans (socioeconomic diversity).

One of the best aspects of taking these sorts of Field Trips at the ESA meeting is that doing so allows you to get to know other people with similar interests. The group of people assembled for this walk were really diverse from a scientific perspective, although there did seem to be a lot of people with specialized plant knowledge. And although our group clearly slanted towards people who do a lot of teaching, the institutions where we teach were quite varied. What seemed to be a commonality amongst all this diversity was our interest in making a connection between the science we teach and important social issues, and appropriately so: this activity is a wonderful way to allow our students to make the connection between the study of scientific patterns and awareness of social phenomena.

Below is a chronological gallery of selected photographs that I took on the tour, with narrative captions:

A Major Post, Anthropogenic Change, Cultural Anthropology, Ecological Society of America, Ecology, Economic sustainability, Economics, Ecosystem Services, Environmental Justice, Population Pressure, Public Policy, Sustainability, Sustainable Urban Design, Urban Planning

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