4
Soil Taxonomic Structure and Factors
Affecting Soil Distribution in the Great Lakes
Coastal Zone
4.1
Soil Taxonomic Structure in the US
Great Lakes Coastal Zone
There are six orders, 16 suborders, 39 great groups, 140
subgroups, 507 families, and 691 soil series in the
US GLCZ. Of the 691 soil series in the US GLCZ, 28% are
Alfisols 26% are Spodosols, 19% are Inceptisols, 12% are
Entisols, 11% are Mollisols, and 4% are Histosols
(Table 4.1). Ten great groups account for 65% of the soil
series, including Haplorthods (16%), Hapludalfs (12%),
Glossudalfs (7.1%), Endoaquepts (5.2%), Endoaquolls
(4.6%), Eutrudepts (4.6%), Endoaqualfs (4.5%), Udipsamments (4.2%), Haplosaprists (3.5%), and Epiaquepts (3.5%)
(Fig. 4.1).
Nearly a third (28%) of the soil series follow the central
concept of a taxon, i.e., Typic and Haplic subgroups
(Fig. 4.2). Nearly half (45%) of the soil series are extragrades in that they deviate from the central concept of a
taxon. Drainage is the key factor in this deviation,
accounting for 30% of the soil series. More than one-quarter
(27%) of the soil series are intergrades, which are soils that
have properties linking them with other soil orders. These
orders are most commonly Mollisols, Alfisols, and Entisols,
but include a few Histosols and Spodosols.
The distribution of soil families suggests that 71% of the
soil series are in loamy (coarse-loamy, fine-loamy, and
loamy) and sandy (sandy and sandy-skeletal) particle-size
classes, 81% are in the mixed soil-mineral class, about half
are in the frigid soil-temperature class (the other half is
mesic), and about half are in active and superactive CEC
activity classes (Fig. 4.3). Aquic soils (Hemists, Saprists,
Aqualfs, Aquods, Aquepts, Aquolls, and Aquents) account
for 42% of the soil series (Table 4.2).
4.2
Soil Taxonomic Structure
in the Canadian Great Lakes Coastal
Zone
A total of 205 soil series occur along the mapped portions of
the Canadian Great Lakes coastal zone; more than
three-quarters of the soil subgroups are Orthic Humic
Gleysols (22%), Brunisolic Gray Brown Luvisols (20%),
Gleyed Gray Brown Luvisols (10%), and Orthic Melanic
Brunisols (10%) (Fig. 4.4). A large portion of the unmapped
Canadian GLCZ is provisionally mapped as Humo-Ferric
Podzols (Great Lakes Forestry Centre). Most of these soils
would be classified as Haplorthods in ST. For this reason,
the proportion of Luvisols (51%) in the Canadian GLCZ is
substantially greater the proportion of Alfisols (28%) in the
US GLCZ; and the proportion of Gleysols (27%) in the
Canadian GLCZ is larger than the proportion of Aquents,
Aquepts, and Aquolls (23%) in the GLCZ. Whereas Histosols occupy 4.0% of the US GLCZ, Organic soil series
comprise less than 1% of the Canadian GLCZ. However,
landforms identified as “marshes” and “bogs” in Canada
may contain Histosols, as well as wet mineral soils. Whereas
5.4% of the US GLCZ features Psamments, Orthic Regosols
compose less than 1% of the Canadian GLCZ.
In the US GLCZ, 42% of the soils are aquic, i.e., are
either Hemists or Saprists or occur in Aqu-suborders of
mineral soils (Table 4.2). In the Canadian GLCZ, 55% of the
soil series are Gleysols or in Gleyed subgroups. In the US
GLCZ, the largest proportion (42%) of the soil series are in
loamy particle-size classes and 30% are in sandy classes;
81% of the soil series have a mixed mineralogy; 48% of the
series are in superactive and active cation-exchange-capacity
activity classes; and the proportion of soils are equally
© Springer Nature Switzerland AG 2021
J. G. Bockheim, Soils of the Laurentian Great Lakes, USA and Canada,
https://doi.org/10.1007/978-3-030-52425-8_4
43
Soil Taxonomic Structure and Factors
Affecting Soil Distribution in the Great Lakes
Coastal Zone
4.1
Soil Taxonomic Structure in the US
Great Lakes Coastal Zone
There are six orders, 16 suborders, 39 great groups, 140
subgroups, 507 families, and 691 soil series in the
US GLCZ. Of the 691 soil series in the US GLCZ, 28% are
Alfisols 26% are Spodosols, 19% are Inceptisols, 12% are
Entisols, 11% are Mollisols, and 4% are Histosols
(Table 4.1). Ten great groups account for 65% of the soil
series, including Haplorthods (16%), Hapludalfs (12%),
Glossudalfs (7.1%), Endoaquepts (5.2%), Endoaquolls
(4.6%), Eutrudepts (4.6%), Endoaqualfs (4.5%), Udipsamments (4.2%), Haplosaprists (3.5%), and Epiaquepts (3.5%)
(Fig. 4.1).
Nearly a third (28%) of the soil series follow the central
concept of a taxon, i.e., Typic and Haplic subgroups
(Fig. 4.2). Nearly half (45%) of the soil series are extragrades in that they deviate from the central concept of a
taxon. Drainage is the key factor in this deviation,
accounting for 30% of the soil series. More than one-quarter
(27%) of the soil series are intergrades, which are soils that
have properties linking them with other soil orders. These
orders are most commonly Mollisols, Alfisols, and Entisols,
but include a few Histosols and Spodosols.
The distribution of soil families suggests that 71% of the
soil series are in loamy (coarse-loamy, fine-loamy, and
loamy) and sandy (sandy and sandy-skeletal) particle-size
classes, 81% are in the mixed soil-mineral class, about half
are in the frigid soil-temperature class (the other half is
mesic), and about half are in active and superactive CEC
activity classes (Fig. 4.3). Aquic soils (Hemists, Saprists,
Aqualfs, Aquods, Aquepts, Aquolls, and Aquents) account
for 42% of the soil series (Table 4.2).
4.2
Soil Taxonomic Structure
in the Canadian Great Lakes Coastal
Zone
A total of 205 soil series occur along the mapped portions of
the Canadian Great Lakes coastal zone; more than
three-quarters of the soil subgroups are Orthic Humic
Gleysols (22%), Brunisolic Gray Brown Luvisols (20%),
Gleyed Gray Brown Luvisols (10%), and Orthic Melanic
Brunisols (10%) (Fig. 4.4). A large portion of the unmapped
Canadian GLCZ is provisionally mapped as Humo-Ferric
Podzols (Great Lakes Forestry Centre). Most of these soils
would be classified as Haplorthods in ST. For this reason,
the proportion of Luvisols (51%) in the Canadian GLCZ is
substantially greater the proportion of Alfisols (28%) in the
US GLCZ; and the proportion of Gleysols (27%) in the
Canadian GLCZ is larger than the proportion of Aquents,
Aquepts, and Aquolls (23%) in the GLCZ. Whereas Histosols occupy 4.0% of the US GLCZ, Organic soil series
comprise less than 1% of the Canadian GLCZ. However,
landforms identified as “marshes” and “bogs” in Canada
may contain Histosols, as well as wet mineral soils. Whereas
5.4% of the US GLCZ features Psamments, Orthic Regosols
compose less than 1% of the Canadian GLCZ.
In the US GLCZ, 42% of the soils are aquic, i.e., are
either Hemists or Saprists or occur in Aqu-suborders of
mineral soils (Table 4.2). In the Canadian GLCZ, 55% of the
soil series are Gleysols or in Gleyed subgroups. In the US
GLCZ, the largest proportion (42%) of the soil series are in
loamy particle-size classes and 30% are in sandy classes;
81% of the soil series have a mixed mineralogy; 48% of the
series are in superactive and active cation-exchange-capacity
activity classes; and the proportion of soils are equally
© Springer Nature Switzerland AG 2021
J. G. Bockheim, Soils of the Laurentian Great Lakes, USA and Canada,
https://doi.org/10.1007/978-3-030-52425-8_4
43