saturation, Fe d or Fe o , Al d or Al o , and cation-exchange capacity at pH 7 and pH in water.
Preference was given to pedons in the GLCZ and with complete data.
Pedodiversity
Pedodiversity of the US GLCZ was determined from mean density of soil series (number of
soil series, divided by area) (Bockheim, 2018). Endemic soils are defined as the only soil in a
family (Bockheim, 2005). Rare soils are those with an area less than 10,000 ha (Ditzler, 2003).
Endangered soils are defined here as those that are endemic and rare.
Soil-Forming Processes
Dominant soil-forming processes were identified based on taxonomic category (Bockheim and
Gennadiyev, 2000). Primary processes were identified at the order (e.g., Spodosol = podsolization) and suborder (e.g., Aquept = gleization) levels; and secondary processes were
assigned from the great-group (e.g., Argiudoll = argilluviation) and subgroup
(Spodic = podsolization) levels.
Soil Evolution
Soil series were assigned to proglacial lakes in the Great Lakes basin by comparing soil extent
maps with maps of prominent shorelines (Fig. 2.15). Ages were assigned using the
post-glacial lake chronology given in Table 2.1. The evolution of soils derived from stabilized
sand dunes, beach ridges, and sandy lake terraces was determined from an integration of seven
published soil chronosequences-chronofunctions conducted along the Lake Michigan and
Lake Huron shores.
Soil Photographs
County soil survey reports were an excellent source for color images of key soil series.
Additionally, I used personal photographs and those from colleagues.
Additional Information
Other materials that were consulted in preparing this report included research publication
identified electronically from the Web of Science, county soil survey reports, the Web Soil
Survey (https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm), the US Geological
Survey national topographic map (https://viewer.nationalmap.gov/launch/), the Great Lakes
Shoreviewer (http://superiorwatersheds.org/shorelineviewer2011/), and the Quaternary Geologic Atlas of the USA (US Geological Survey, 2012).
xii
Author’s Note
Preference was given to pedons in the GLCZ and with complete data.
Pedodiversity
Pedodiversity of the US GLCZ was determined from mean density of soil series (number of
soil series, divided by area) (Bockheim, 2018). Endemic soils are defined as the only soil in a
family (Bockheim, 2005). Rare soils are those with an area less than 10,000 ha (Ditzler, 2003).
Endangered soils are defined here as those that are endemic and rare.
Soil-Forming Processes
Dominant soil-forming processes were identified based on taxonomic category (Bockheim and
Gennadiyev, 2000). Primary processes were identified at the order (e.g., Spodosol = podsolization) and suborder (e.g., Aquept = gleization) levels; and secondary processes were
assigned from the great-group (e.g., Argiudoll = argilluviation) and subgroup
(Spodic = podsolization) levels.
Soil Evolution
Soil series were assigned to proglacial lakes in the Great Lakes basin by comparing soil extent
maps with maps of prominent shorelines (Fig. 2.15). Ages were assigned using the
post-glacial lake chronology given in Table 2.1. The evolution of soils derived from stabilized
sand dunes, beach ridges, and sandy lake terraces was determined from an integration of seven
published soil chronosequences-chronofunctions conducted along the Lake Michigan and
Lake Huron shores.
Soil Photographs
County soil survey reports were an excellent source for color images of key soil series.
Additionally, I used personal photographs and those from colleagues.
Additional Information
Other materials that were consulted in preparing this report included research publication
identified electronically from the Web of Science, county soil survey reports, the Web Soil
Survey (https://websoilsurvey.sc.egov.usda.gov/App/HomePage.htm), the US Geological
Survey national topographic map (https://viewer.nationalmap.gov/launch/), the Great Lakes
Shoreviewer (http://superiorwatersheds.org/shorelineviewer2011/), and the Quaternary Geologic Atlas of the USA (US Geological Survey, 2012).
xii
Author’s Note