Anthropogenic effects on the physical and chemical properties of subtropical coastal urban soils

Abstract

We investigated the effects of various anthropogenic factors on urban soil properties in subtropical, coastal Tampa, FL, USA. Specifically, we explored the influence of (i) urbanization as measured by land use, land cover, population density and years since urban development and (ii) socioeconomic conditions as reflected in household income and property values on bulk density (BD) and several key soil chemical properties. Results indicate that Tampa’s urban soils were affected to varying degrees by these factors with chemical properties being more variable than BD. Across land uses significant differences were found for Mehlich‐1 (M1) extractable P, Ca and Na. A similar trend was observed for land‐cover classes, although significant differences were also found for pH and M1‐Cu. Soil properties had no statistically significant relationship with population density. However, time since urbanization did with M1‐P and Na varying significantly across age categories. For our socioeconomic analyses, M1‐K and Mg levels differed significantly by household income while pH, P, Ca and Na values differed significantly by property value. Overall, our findings indicate that despite their inherent heterogeneity, there are identifiable patterns among subtropical coastal urban soil properties. We suggest that a more thorough understanding of these patterns and their drivers is an essential first step towards developing soil management strategies aimed at maintaining environmental quality and ecosystem services in subtropical cities.

DOC and DON Release and Reactive Soil Pools in Urban and Remnant Soils

“…We also found significantly higher calcium concentrations in urban soils relative to remnant soils that included forests, pasture, shrub scrub, and wetlands. Our results were similar to those of the study of Hagan et al (2012) who reported no significant difference in soil calcium among commercial and residential sites, but we found significantly increased soil calcium in urban open areas (parks) relative to single-family homes, which we attributed to gypsum application by city municipalities. Soil concentration of sodium in Tampa (9-29 mg kg −1 ) (Hagan et al, 2012) was extremely low relative to the soils in Texas (20-1,142 mg kg −1 ); this can probably be attributed to differences in source water used for potable water.…”

“…Municipal drinking water in Tampa has sodium concentrations of 55 mg L −1 (City of Tampa Water Quality Report 2012) compared with 226 mg L −1 in Bryan and College Station (Table 1). Whereas Hagan et al (2012) reported significantly higher soil sodium in residential soil, their soil sodium was not significantly higher compared with that in forest soil. Based on the vicinity of Tampa to the ocean, we believe that this may have been an effect of the forest canopy scavenging of oceanic aerosols in their study.…”

“…Calcium concentrations in commercial and institutional urban soils are significantly higher than in residential, forest, or agricultural soils in the subtropical climate of Tampa, FL (Hagan et al, 2012). We also found significantly higher calcium concentrations in urban soils relative to remnant soils that included forests, pasture, shrub scrub, and wetlands.…”

“…Furthermore, the largest percent change in urbanized land between 1982 and 1997 occurred in southern United States (Fulton et al, 2001). In general, research on urban soil chemistry has increased during the last decade (e.g., Baker et al, 2001;Groffman et al, 2004;Kaye et al, 2005;Wong et al, 2006;Beesley, 2012;Hagan et al, 2012;Steele and Aitkenhead-Peterson, 2012a, b). But many urban studies however concentrate on heavy metals and other cations (e.g., Wong et al, 2006;Hagan et al, 2012;El Khalil et al, 2013) or nitrogen and phosphorus as a response to increased fertilizer use or pet feces (Baker et al, 2001;Groffman et al, 2004).…”

Vegetation Type and Age Drive Changes in Soil Properties, Nitrogen, and Carbon Sequestration in Urban Parks under Cold Climate

“…This also suggests that urban park soils have abundant earthworm populations regardless of age and vegetation and that they do not develop podzols typical to the boreal biome. Furthermore, as shown in several studies, urban soils typically have high pH (e.g., Craul and Klein, 1980;Jim, 1993;Hagan et al, 2012;Kuoppamäki et al, 2014), resulting from materials used in urban infrastructure that are high in calcium, such as concrete (Pouyat et al, 2007b). It is possible that substantial Ca inputs result in oversaturation of Ca and other cations in urban soils, which-in turn-inhibit clear soil stratification indicative of boreal forests.…”