Anthropogenic Effects On the Physical and Chemical Properties of Urban Soils In Tampa, FL, USA.

We investigated the effects of various anthropogenic factors on urban soil physical and chemical properties in subtropical, coastal Tampa, Florida, United States.  Specifically, we explored the effects of (1) urbanization as measured by land use, land cover, population density, and years since urban development and (2) socioeconomics as measured by household income and property values, on key soil physical and chemical properties. Results indicate that Tampa’s urban soils were affected––to varying degrees––by these multi-scale factors, with land cover and property value having the most pronounced effects.  While soil chemical properties typically had higher coefficients of variation than physical properties, distinct statistical relationships were observed for both.  Soil phosphorus (P) and sodium (Na) contents were highest in residential land uses and soil calcium (Ca) was highest in commercial land uses. Urban forest soils had the lowest bulk densities, were more acidic, and had lower nutrient and metal contents than other land covers. Soil P and Na were lowest in recently urbanized plots.  Soil bulk density was not influenced by socioeconomic factors, but significant relationships were found for several soil chemical properties. Soil Ca and Mg contents, for example, were significantly greater in lower income areas and pH, P, Ca and Na were lowest in the lowest property value class (<$60,000 USD). Our methods and results could be used to assess the role of urban soils in maintaining environmental quality in subtropical cities. Findings also provide insight into the complexity of subtropical, coastal urban soils and the multiple scale drivers affecting urban soil quality and ecosystem services.