Kaelyn Wilke Analysis of Urban Structure in Minnesota’s Twin Cities: Accessibility and Land Use Bolobilly at

Presentation Outline Background Previous Research Research Question Maps of the Study Area, Buffer Zones, and Land Use Methods Variable Layers and Results Conclusions Future Research Data Sources Bibliography

Urban Structure and Growth Urban structure Layout of how land is used in a city crimetheory.com, gearthblog.com Denver

Urban Structure and Growth One of the most famous models is the Concentric Zone Model –Origin: Henry Burgess, 1920s –Explains land use as expanding out of a central business district, or CBD. –Good demonstration of the attempt to classify trends in the development of cities, or urban structure. crimetheory.com, gearthblog.com Denver

Urban Centrality and Accessibility Does the method of measurement depend on the model?

Background Urban structure is a prominent theme in urban geography. Another aspect examined in urban development is accessibility. Accessibility refers to the ease of traveling from one location to another. Could there be a causal relationship between accessibility and land use? If so, there should be correlations of a measure of accessibility with the exploitation and infrastructure of the city.

Previous Research Relationship between accessibility and land use Two ways to measure accessibility Relative Accessibility –Proximity to downtown Integral Accessibility –Travel times and network connectivity Stanilov, Kiril Accessibility and Land Use: The Case of Suburban Seattle, 1960–1990. Regional Studies, Vol. 37.8, pp. 783–794.

Previous Research Two-way relationship between land use and accessibility Ottensmann, John, R., Using the Land Use in Central Indiana (LUCI) Models in Transportation Planning, Indiana University Purdue University Indianapolis Esri, Opus Corp Land use affects accessibility Accessibility and transportation affect or lead to changes in land use

Previous Research Issues with accessibility –Personal choice –Impedance –Population traits (age, socio-economics) Method of measurement –Polygon –Patterns of human behavior –Infrastructure Makri, M.C., Folkesson, C. Accessibility Measures for Analyses of Land Use and Travelling with Geographical Information Systems Lund Universtiy, Sweden. University of Karlskrona?Ronneby, Sweden. nytimes.com, pro.corbis.com, flickr- Aaron Michael Brown

Research Questions What are appropriate measures of accessibility? How does accessibility affect the land use in the Twin Cities? –Canopy, Pavement, Farmland, Retail panoramas.com

Study Area Twin Cities of Minnesota The metropolitan area includes the seven counties: Ramsey, Hennepin, Anoka, Scott, Dakota, Carver, and Washington.

The Concept of Creating Buffers Buffers were created to encompass different modes of accessibility in order to relate it to land use: hamptonroads.com/node/204931; Relative accessibility: steady outward distances from CDB Integral accessibility: time to travel to highway intersections

Map of Buffer Zones Distance from Downtowns

Map of Buffer Zones Time to Intersections: The place where highways crossed or meet has been termed “intersections.” Polynucleated urban space

Example of Buffer Use: Farmland

Appropriate Buffer Zones as Measures of Accessibility Unit of measure is in distance Unit of measure is in time

Methods Note: any variable can be inserted where it says “Landuse Type.”

Map of Variable: Canopy Tree coverage over the seven metropolitan counties. Dark blue denotes the most tree coverage, and tan denotes the least tree coverage.

Results: Canopy Layer

Map of Variable: Imperviousness Areas in the seven metropolitan counties characterized by spans of concrete. Dark green signifies the most impervious areas (“most concrete”), and tan denotes the least impervious areas (“least concrete”).

Results: Imperviousness Layer

Map of Variable: Retail and Other Commercial Land Use Areas in the seven metropolitan counties characterized by spans of infrastructure. Red shading denotes map parcels with retail and commercial uses.

Results: Retail and Other Commercial Land Use Layer

Conclusions The results support the theory that accessibility affects land use.

When used with the “Distance to Downtowns” and “Time to Intersections” buffer, very little trees are seen closest to downtowns or highway intersections, respectively. Expanding outward, the amount of tree coverage steadily increased. Conclusion: Canopy Layer

Conclusion: Impervious Layer When used with the “Distance to Downtowns” buffer and “Time to Intersections” buffer, the results showed a lot of concrete near downtowns or highway intersections, respectively. Expanding outward, the land is less covered with pavement.

The results supported the theory that accessibility dictates land use. Retail and other commercial land uses were each prevalent with the CBD. Is one buffer better than the other in terms of measuring urban structure? In other words, does the Concentric Zone Model still apply to urban development today? Conclusions: Land Use Layers

Appropriate Buffer Zones as Measures of Accessibility *Distance *Relative Accessibility *Time *Integral Accessibility *One center *Network *Polynuceated Both models are comparable for canopy and impervious layers Some difference is seen in the RCO layer Large categories More specific categories

Future Research What type of variables are buffer- dependent? (Model dependent) Apply the same methods to different cities to see if urban structure varies enough to affect accessibility, which affects land use.

Data Sources National Land Cover Database Tree Canopy Layer Homer, C., C. Huang, L. Yang, B. Wylie and M. Coan, Development of a 2001 national land cover database for the United States. Photogrammetric Engineering and Remote Sensing. National Land Cover Database Zone 51 Imperviousness Layer Yang, L, C. Huang, C. Homer, B. Wylie, and M. Coan, An approach for mapping large- area impervious surfaces: Synergistic use of Landsat 7 ETM+ and high spatial resolution imagery. Canadian Journal of Remote Sensing, 29: 2, Generalized Land Use - Historical 1984, 1990, 1997, 2000 and 2005, for the Twin Cities Metropolitan Area Metropolitan Council. This dataset can be downloaded from TLG Street Centerline and Address Ranges The Lawrence Group. Distributed by the Metropolitan Council

Bibliography Stanilov, Kiril Accessibility and Land Use: The Case of Suburban Seattle, 1960–1990. Regional Studies, Vol. 37.8, pp. 783–794. Makri, M.C., Folkesson, C. Accessibility Measures for Analyses of Land Use and Travelling with Geographical Information Systems Lund Universtiy, Sweden. University of Karlskrona?Ronneby, Sweden. Ottensmann, John, R., Using the Land Use in Central Indiana (LUCI) Models in Transportation Planning, Indiana University Purdue University Indianapolis Also, thanks to Dr. Paul Lorah, Renee Huset, and Jeff Dodson

Thank You Questions?