Soil profile changes in urban areas

A study documents soil profile changes in urban areas in the United States. Soil makeup is key to ecosystem structure and function. Urbanization changes the properties of soils and can influence ecosystem functioning. Dustin Herrmann, Laura Schifman, and William Shuster analyzed soil horizons in 11 US cities; soil horizons are the stratigraphic and morphological layering of soils and include three main ordered categories, namely A, B, and C. The researchers compared samples from 332 urban soil profiles to soil profiles representative of pre-urban soils in the cities, and found that the urban soils had approximately 50% fewer soil horizons than pre-urban soils. In particular, B horizons, which form over decades to millennia from an accumulation of materials from surface soils, were less common in urban soils compared with pre-urban soils, and were replaced by a deepening of A horizons and shallowing of C horizons. Additionally, urban soil profiles were more likely than pre-urban soils to vary from the standard A-B-C horizon ordering. The researchers attributed the changes to local management processes such as soil removal, mixing, and fill additions, as well as short time periods for soil horizon development since urbanization. The findings highlight potential effects of soil modification on ecosystem functioning and services in urban areas, according to the authors.

Article #18-00305: "Widespread loss of intermediate soil horizons in urban landscapes," by Dustin Herrmann, Laura Schifman, and William D. Shuster.

MEDIA CONTACT: William D. Shuster, United States Environmental Protection Agency, Cincinnati, OH; tel: 513-569-7244; e-mail: <shuster.william@epa.gov>; Dustin L. Herrmann, United States Environmental Protection Agency, Cincinnati, OH; tel: 513-569-7937; 530-902-9105; email: <herrmann.dustin@epa.gov>

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