Tree Cover Versus Demographics in a Changing Atlanta, 1970s
Map 1
Boundaries for Rings 1 (inner) to 4
My goal here was to empirically define and explore how tree cover varied across locations and lines and race and class in the Atlanta metro area of the 1970s, just as its sprawl had begun to accelerate.
Method: Using ArcMap 10.3, I divvied Atlanta's 1980 census tracts up into four "rings" of approximately equal numbers of tracts, starting with the inner core of the city and moving outward. Tabulating racial and income figures for each tract and its corresponding ring, I then compared tracts including or bordering on forest patches to those that did not, ring by ring.
Source for census data: NHGIS
Map 2
Atlanta Metro Area Forest Cover, Early 1970s
Source: Land Use and Land Cover (LULC) dataset (1 and 2, 1975-77) developed from orginal sources dating between 1972-1976 by USGS describes the vegetations, water , natural surface, and cultural features on the land. Originally downloaded from Georgia GIS Clearinghouse 6-13-2014.
ring table.xlsxTable 1--Rings by Income, Race, and Forest Patches
While per capita incomes were generally lower, and percentages of Black residents were higher, in the inner most rings, the forested tracts through the first two rings were both whiter and higher income. In ring 3, however, Black percentages were higher in the forested tracts. And in ring 4, forests made less of a difference for both race and income. "Centroid" here is the centermost point geometrically of a given tract.
Chart 1
This and the rest of this series of ten charts dissect the data mentioned and cited above to show the patterns of residence in forested versus unforested tracts by ring, also by race and class (the latter defined here in terms of annual income). The percentages offered in charts 3-10 are the average proportion of a given group (whether Black or white, low or medium or high income) in the forested or unforested tracts of a given ring.
Chart 2
Chart 3
Chart 4
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Chart 6
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Chart 8
Chart 9
