How systemic racism shaped the ecosystems of U.S. cities
Human Health & the Environment
Science Magazine, 10 09, 2020
Video (4:08)
Description
Historically Black and immigrant communities are more vulnerable to environmental stressors
Read the research: https://scim.ag/3nzjnQE
Credits
producer
Meagan Cantwell
supervising producer
Joel Goldberd
research
Schell et al., Science 2020
DOI: 10.1126/science.aay4497
special thanks
Elizabeth Pennisi
Pratheek Rebala
Sacha Vigneri
video footage
Meagan Cantwell
Pond5
Videoblocks
Videvo
archival footage
Dynamic Films
Encyclopedia Britannica Films
FDR Presidential Library
Prelinger Archives
photos
Library of Congress
Ted Etyan/Flickr
Will Parson/Chesapeake Bay Program
Enoch Pratt Free Library/Maryland’s State Library Resource Center
illustrations
British Library/Flickr
maps/data
Howard Center for Investigative Journalism/CNS/NPR
Johns Hopkins University
Library of Congress
Meagan Cantwell
Portland State/SUPR Lab
Robert K. Nelson et al., 2020 “Mapping Inequality”
music
“Vultures” by Chris Burns
Transcript
0:01 · The urban environment is a feat of human decision-making— from where to develop street grids lined with large glass office buildings, to which green spaces to preserve for outdoor recreation.
0:13 · How humans make these choices, and the natural environment’s response, can create extremely different ecosystems in neighborhoods just a few blocks away from each other.
0:23 · Researchers delved into dozens of studies to understand what drives these variations.
0:29 · One well documented phenomenon in cities is the relationship between wealth and biodiversity.
0:35 · More affluent areas generally have greater canopy cover, with larger, mature trees, as well as a higher diversity of birds.
0:45 · This is known as the “luxury effect.”
0:48 · Low-income areas typically have more man-made surfaces— including major heat-absorbers like asphalt and concrete, compared to higher-income areas.
0:59 · The lack of shade from trees and vegetation, combined with more asphalt and concrete, makes it hotter in these neighborhoods— a phenomenon known as an “urban heat island.”
1:10 · These communities are also more likely to be near sources of air pollutants, like expansive interstates pumping car exhaust.
1:19 · Although wealth can sometimes predict the outcomes of an urban ecosystem, there isn’t always a clear relationship.
1:26 · In some cases, the racial make-up of a neighborhood is better than income when forecasting canopy cover.
1:33 · Researchers explored studies that highlight how systemic racism shaped our build environment.
1:39 · One glaring example in the United States is residential segregation.
1:44 · From 1933-1968, the federal government limited access to homeownership among Black Americans through a practice known as redlining.
1:55 · Neighborhoods were graded based on the riskiness of providing a mortgage in the area.
2:00 · The grades ranged from A, the most desirable areas, full of wealthy businessmen, to D, neighborhoods considered high-risk investments due to a combination of factors: from their environmental quality and distance from large industrial factories to the main determinant, the presence of foreign-born and Black people.
2:22 · The inability for Black people to buy homes in these neighborhoods meant many types of capital investments left— landlords abandoned their properties, and public services, such as transportation and park maintenance, weren’t prioritized.
2:36 · Today, many U.S. cities still exhibit long-lasting environmental impacts from this discrimination.
2:42 · Neighborhoods which had a “D” grade in the 60s have about half the canopy cover of historically white communities.
2:50 · Some studies evaluate how the current environment relates to historically redlined communities, but researchers did not find any research that traces how ecosystems changed over time because of this segregation.
3:03 · They propose that because habitable regions are more spread out in these areas, animal populations struggle to breed since they are cut off from each other.
3:14 · The reduced breeding options for animals could have decreased gene diversity, an important way for animals to adapt to changing environments.
3:23 · And decreased gene flow of native species could promote the abundance of pest species, like mosquitos and brown rats, which carry diseases that can infect humans.
3:34 · The combination of all these outcomes— from urban heat islands to increased pests— make low-income, marginalized communities far more vulnerable to risks like climate change.
3:47 · Scientists say such evidence shows that conservation and social justice cross paths— especially along neighborhood streets.