Assessing the Relationship between Sidewalk Foot Traffic and Soil Compaction on Dalhousie University’s Studley Campus

Abstract

Keywords: Soil compaction, foot traffic, porosity, bulk density, NDVI, post-secondary institution, linear mixed-effects ANOVA

As cities grow larger there is an increased need to provide walkable areas for pedestrians. However, sidewalks and high foot traffic can create edge effects that alter nearby soil properties, particularly soil compaction. On Dalhousie University's Studley Campus in Halifax, Nova Scotia, heavily trafficked pedestrian areas have led to visible vegetation loss and suspected soil compaction in adjacent greenspaces. The research objective of this study was to examine the effects sidewalks on soil compaction by focusing on three key soil parameters: soil density, dry bulk density, and porosity. Soil samples were collected at seven sidewalk sites around heavily travelled sidewalks on campus as determined by Normalized Difference Vegetation Index (NDVI) data. At each site, samples were collected at distances of 0.1m, 0.5m, and 1m from the sidewalk along a single transect. At each sidewalk site two samples were taken at each distance and averaged to account for variability. Two samples were taken and averaged at each control site which were collected from five low-traffic locations across campus. Laboratory analysis, which included measuring the weights of both wet and dry soil samples, was conducted to measure the average density, dry bulk density and porosity. To analyze the data a linear mixed- effects analysis of variance (ANOVA) was used to identify if there was any statistically significant evidence to suggest a difference between the sidewalk sites and control sites. Contrary to the expectations, the results showed no significant difference in these soil parameters with increasing distance from sidewalks or between sidewalk and control sites. These findings contribute to a growing understanding surrounding urban soil dynamics and suggest that foot traffic-related soil compaction may not play as large a role in soil compaction as previously assumed. Further research is recommended to explore additional variables that may affect soil compaction in urban settings.