Urban Soil Classification: Article Review Lacey Hancotte SWS 4715C–Pedology Spring 2015

Experimental Order 1 soil survey of vacant urban land, Detroit Michigan, USA Jeffrey L. Howard & William D. Shuster CATENA Volume 126 March 2015 Pages 220–230

Research Objectives: assess the mappability of demolition site soils in a typical urban landscape test the hypothesis that there is a mappable pattern of anthropogenic soils “There is a pressing need for soil maps in many urban areas because building demolition has produced large tracts of vacant land. This open space has attracted considerable interest…however, demolition site soils are usually in need of revitalization”

Methods & Area of Study: Perform an Order 1 soil survey (scale = 1:200) Samples were collected using: a Geoprobe, a soil pit, & hand augers Artifacts were separated from the bulk coarse fragment by hand, weighed, and classified into types and numbers of each type counted.

Terminology as Defined by the Article: Human-altered material (HAM) formed in place either by deep mixing, excavation and replacement from a single pedon, or truncation and removal of the surface soil. the term “anthrosol” are used informally for soils formed in HAM Human-transported material (HTM) formed by excavation of material from one pedon and mixing with materials from other pedons, or by moving earth material horizontally onto a pedon from other sources, usually with the aid of hand tools or mechanized equipment the term “technosol” is used informally for soils formed in HTM These soils are roughly equivalent to the corresponding Reference Soil Groups in the World Reference Base

Characteristics of anthropic soils in the sampling grid: Technosol Anthrosol Type A Type B Type C Type S Depth (cm)Description Depth (cm) Description Depth (cm) Description Depth (cm) Description 0–102 ^Au, Black (10YR2/1), light clay loam; 5 to 10% artifacts 0–20 ^Au, Black (10YR2/1), light clay loam; b5% artifacts 0–56 ^Au, Black (10YR2/1), light clay loam; b5% artifacts 0–30 ^Au, Black (10YR2/1), sandy clay loam; b5 % artifacts 102–137 ^Cu, Dark gray (10YR4/1), heavy clay loam; b5% artifacts 20–55 ^Cu, Dark gray (10YR4/1), heavy clay loam; b5 % artifacts 56–102 ^Cu, mixed mottled gray (10YR5/1) and dark brown (10YR4/3), heavy clay loam; b5% artifacts 30–44 ^A, Very dark gray (10YR3/1), sandy clay loam 137–150 C, mottled gray (10YR5/1) and strong brown (7.5YR5/6), heavy clay loam 55–69 Ab, Very dark gray (10YR3/1), light clay loam 102+ C, mottled gray (10YR5/1) and strong brown (7.5YR5/6), heavy clay loam 44–61 ^C and mixed ^A and ^C, Dark gray (10YR4/1), sandy clay loam 69–112 C, mottled gray (10YR5/1) and strong brown (7.5YR5/6), heavy clay loam 61–76 C, mottled gray (10YR5/1) and dark brown (10YR4/3), sandy clay loam 76+ 2C, mottled gray (10YR5/1) and strong brown (7.5YR5/6), heavy clay loam

Results & Findings: Artifacts…Complex Horizonization…

Fig. 3. Map of soil types and other characteristics at the study site A: Soil map based on 2 m grid spacing; B: Borings where auger refusals (AR) occurred; C: Isopach map of ^Au horizon thickness (cm); D: Isopach map of approximate fill thickness based on maximum depth (cm) of artifacts.

Discussion: ^A horizons have formed in demolition site soils within ~15 to 20 years under grass vegetation (Howard and Olszewska, 2011; Howard et al., 2013a) Other studies have also shown that topsoils can develop in human-transported material within a few a decades or less The standard approach of mapping soils on the basis of landscape position, and morphological characteristics ascertained with a hand auger, is difficult or impossible to apply in most urban areas because: 1) The land usually has been leveled by earthmoving equipment 2) Auger refusals occur 50 to 90% of the time 3) The morphological properties of soils and anthropogenic parent materials are geospatially variable. The properties of demolition site soils can be predicted to some extent based on prior land use history, which can possibly be gleaned from Sanborn fire insurance and similar maps, aerial photographs, public records pertaining to building construction, demolition and utilities, and newspaper accounts. However, historic records are often incomplete, inaccurate or unavailable. The data suggest that the history of the site studied can be reconstructed from the spatial distribution of artifacts and soil types There are mappable patterns of anthropogenic soils in urban settings

Fig. 9. Genetic model showing how construction and demolition processes affect demolition site stratigraphy and anthrosequence development: A: residential site prior to construction B: Inverted stratigraphy resulting from excavation for basement C: stratigraphy following demolition and backfilling D, E, and F: map views of A, B and C, respectively NS: native soil CF: construction fill DF: demolition fill Sx, glaciolacustrine sand capping Dc: clayey diamicton S = f(C, R, O, P, T, A)

Special thanks too: Jeffrey Howard & William Shuster for their research and advancements made in the name of Soil Science. & Professor WillIe Harris For providing me with a greater understanding of soil taxonomy, soil mineralogy and soil interpretations.