Ключи к почвенной таксономии 2014

1.  Throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0; and

2.  When neither irrigated nor fallowed to store moisture, either:

a.  A mesic or thermic soil temperature regime and a moisture control section that in normal years is dry in some part for 135 or fewer of the cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 5 oC; or

b.  A hyperthermic, isomesic, or warmer iso soil temperature regime and a moisture control section that in normal years is dry in some or all parts for fewer than 120 cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 8 oC.

Udandic Kanhaplustults

HDCF.  Other Kanhaplustults that have, throughout one or more horizons with a total thickness of 18 cm or more within

75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0.

Andic Kanhaplustults

HDCG.  Other Kanhaplustults that have 5 percent or more (by volume) plinthite in one or more horizons within 150 cm of the mineral soil surface.

Plinthic Kanhaplustults

HDCH.  Other Kanhaplustults that:

1.  Have, in one or more horizons within 75 cm of the mineral soil surface, redox concentrations, a color value, moist, of 4 or more, and hue that is 10YR or yellower and becomes redder with increasing depth within 100 cm of the mineral soil surface; and

2.  In normal years are saturated with water in one or more layers within 100 cm of the mineral soil surface for either or both:

fallowed to store moisture, have either:

1.  A thermic, mesic, or colder soil temperature regime and

a moisture control section that in normal years is dry in some part for more than four-tenths of the cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 5 oC; or

2.  A hyperthermic, isomesic, or warmer iso soil temperature regime and a moisture control section that in normal years:

fallowed to store moisture, have either:

1.  A mesic or thermic soil temperature regime and a moisture control section that in normal years is dry in some part for 135 or fewer of the cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 5 oC; or

2.  A hyperthermic, isomesic, or warmer iso soil temperature regime and a moisture control section that in normal years is dry in some or all parts for fewer than 120 cumulative days per year when the soil temperature at a depth of 50 cm below the soil surface is higher than 8 oC.

Udic Kanhaplustults

HDCK.  Other Kanhaplustults that have, in all subhorizons in the upper 50 cm of the kandic horizon or throughout the entire kandic horizon if it is less than 50 cm thick, more than 50 percent colors that have all of the following:

1.  Hue of 2.5YR or redder; and 2.  A value, moist, of 3 or less; and

3.  A dry value no more than 1 unit higher than the moist value.

Rhodic Kanhaplustults

HDCL.  Other Kanhaplustults.

Typic Kanhaplustults

Paleustults

Key to Subgroups

HDDA.  All Paleustults.

Typic Paleustults

U L T

Plinthustults

Key to Subgroups

HDAA.  Plinthustults that have either:

1.  A densic, lithic, paralithic, or petroferric contact within 150 cm of the mineral soil surface; or

2.  Within 150 cm of the mineral soil surface, both:

a.  With increasing depth, a clay decrease of 20 percent or more (relative) from the maximum clay content; and

b.  Less than 5 percent (by volume) skeletans on faces of peds in the layer that has a 20 percent lower clay content or, below that layer, a clay increase of less than 3 percent

(absolute) in the fine-earth fraction.

Haplic Plinthustults

HDAB.  Other Plinthustults.

Typic Plinthustults

Rhodustults

Key to Subgroups

HDEA.  Rhodustults that have a lithic contact within 50 cm of the mineral soil surface.

Lithic Rhodustults

HDEB.  Other Rhodustults that have a sandy particle-size class throughout the upper 75 cm of the argillic horizon or throughout the entire argillic horizon if it is less than 75 cm thick.

Psammentic Rhodustults

HDEC.  Other Rhodustults.

Typic Rhodustults

Xerults

Key to Great Groups

HEA.  Xerults that:

1.  Do not have a densic, lithic, or paralithic contact within 150 cm of the mineral soil surface; and

2.  Within 150 cm of the mineral soil surface, either:

a.  With increasing depth, do not have a clay decrease of 20 percent or more (relative) from the maximum clay content; or

b.  Have 5 percent or more (by volume) skeletans on faces of peds or 5 percent or more (by volume) plinthite, or both, in the layer that has a 20 percent lower clay content and, below that layer, a clay increase of 3 percent or more (absolute) in the fine-earth fraction.

Palexerults, p. 303

HEB.  Other Xerults.

Haploxerults, p. 302

Haploxerults

Key to Subgroups

HEBA.  Haploxerults that have both of the following:

1.  A lithic contact within 50 cm of the mineral soil surface; and

2.  In each pedon, a discontinuous argillic or kandic horizon that is interrupted by ledges of bedrock.

Lithic Ruptic-Inceptic Haploxerults

HEBB.  Other Haploxerults that have a lithic contact within 50 cm of the mineral soil surface.

Lithic Haploxerults

HEBC.  Other Haploxerults that have, in one or more subhorizons within the upper 25 cm of the argillic or kandic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Haploxerults

HEBD.  Other Haploxerults that have, throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0.

Andic Haploxerults

HEBE.  Other Haploxerults that have an argillic or kandic horizon that:

1.  Consists entirely of lamellae; or

2.  Is a combination of two or more lamellae and one or more subhorizons with a thickness of 7.5 to 20 cm, each layer with an overlying eluvial horizon; or

3.  Consists of one or more subhorizons that are more than 20 cm thick, each with an overlying eluvial horizon, and above these horizons there are either:

a.  Two or more lamellae with a combined thickness of 5 cm or more (that may or may not be part of the argillic or kandic horizon); or

b.  A combination of lamellae (that may or may not be part of the argillic or kandic horizon) and one or more parts of the argillic or kandic horizon 7.5 to 20 cm thick, each with an overlying eluvial horizon.

Lamellic Haploxerults

HEBF.  Other Haploxerults that have a sandy particle-size class throughout the upper 75 cm of the argillic or kandic horizon or throughout the entire horizon if it is less than 75 cm thick.

Psammentic Haploxerults

HEBG.  Other Haploxerults that have a texture class (fineearth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the mineral soil surface to the top of an argillic or kandic horizon at a depth of 50 to 100 cm.

Arenic Haploxerults

HEBH.  Other Haploxerults that have a texture class (fineearth fraction) of coarse sand, sand, fine sand, loamy coarse sand, loamy sand, or loamy fine sand throughout a layer extending from the mineral soil surface to the top of an argillic or kandic horizon at a depth of 100 cm or more.

Grossarenic Haploxerults

HEBI.  Other Haploxerults.

Typic Haploxerults

Palexerults

Key to Subgroups

HEAA.  Palexerults that have both of the following:

1.  In one or more subhorizons within the upper 25 cm of the argillic or kandic horizon, redox depletions with a

color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage); and

2.  Throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0.

Aquandic Palexerults

HEAB.  Other Palexerults that have, in one or more subhorizons within the upper 25 cm of the argillic or kandic horizon, redox depletions with a color value, moist, of 4 or more and chroma of 2 or less, accompanied by both redox concentrations and aquic conditions for some time in normal years (or artificial drainage).

Aquic Palexerults

HEAC.  Other Palexerults that have, throughout one or more horizons with a total thickness of 18 cm or more within 75 cm of the mineral soil surface, a fine-earth fraction with both a bulk density of 1.0 g/cm3 or less, measured at 33 kPa water retention, and Al plus 1/2 Fe percentages (by ammonium oxalate) totaling more than 1.0.

Andic Palexerults

HEAD.  Other Palexerults.

Typic Palexerults

Key to Suborders

FA.  Vertisols that have, in one or more horizons within 50 cm of the mineral soil surface, aquic conditions for some time in normal years (or artificial drainage) and one or both of the following:

1.  In more than half of each pedon, either on faces of peds or in the matrix if peds are absent, 50 percent or more chroma of either:

a.  2 or less if redox concentrations are present; or b.  1 or less; or

2.  Enough active ferrous iron to give a positive reaction to alpha,alpha-dipyridyl at a time when the soil is not being irrigated.

1.  A thermic, mesic, or frigid soil temperature regime; and 2.  If not irrigated during the year, cracks that remain both:

a.  5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 60 or more consecutive days during the 90 days following the summer solstice; and

b.  Closed for 60 or more consecutive days during the 90 days following the winter solstice.

Xererts, p. 315

FD.  Other Vertisols that, if not irrigated during the year, have cracks in normal years that remain closed for less than 60 consecutive days during a period when the soil temperature at a depth of 50 cm from the soil surface is higher than 8 oC.

Torrerts, p. 309

FE.  Other Vertisols that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year.

Usterts, p. 311

FF.  Other Vertisols.

Uderts, p. 310

Aquerts

Key to Great Groups

FAA.  Aquerts that have within 100 cm of the mineral soil surface either:

1.  A sulfuric horizon; or

horizons with a total thickness of 25 cm or more within 50 cm of the mineral soil surface, both:

1.  An electrical conductivity in the saturation extract of less than 4.0 dS/m at 25 oC; and

2.  ApH value of 4.5 or less in 0.01 M CaCl2 (5.0 or less in 1:1 water).

V E R

Calciaquerts

Key to Subgroups

FAEA.  Calciaquerts that have, in one or more horizons between either an Ap horizon or a depth of 25 cm from the mineral soil surface, whichever is deeper, and either a depth of 75 cm or the upper boundary of a duripan if shallower, 50 percent or more colors as follows:

1.  Hue of 2.5Y or redder and either:

a.  Acolor value, moist, of 6 or more and chroma of 3 or more; or

b.  A color value, moist, of 5 or less and chroma of 2 or more; or

2.  Hue of 5Y and chroma of 3 or more; or

3.  Chroma of 2 or more and no redox concentrations.

Aeric Calciaquerts

FAEB.  Other Calciaquerts.

Typic Calciaquerts

Duraquerts

Key to Subgroups

FACA.  Duraquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 210 or more cumulative days per year.

Aridic Duraquerts

FACB.  Other Duraquerts that have a thermic, mesic, or frigid soil temperature regime and that, if not irrigated during the year, have cracks in normal years that remain both:

1.  5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 60 or more consecutive days during the 90 days following the summer solstice; and

2.  Closed for 60 or more consecutive days during the 90 days following the winter solstice.

Xeric Duraquerts

FACC.  Other Duraquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year.

Ustic Duraquerts

FACD.  Other Duraquerts that have, in one or more horizons between either an Ap horizon or a depth of 25 cm from the mineral soil surface, whichever is deeper, and either a depth

of 75 cm or the upper boundary of the duripan if shallower, 50 percent or more colors as follows:

1.  Hue of 2.5Y or redder and either:

a.  Acolor value, moist, of 6 or more and chroma of 3 or more; or

b.  A color value, moist, of 5 or less and chroma of 2 or more; or

2.  Hue of 5Y and chroma of 3 or more; or

3.  Chroma of 2 or more and no redox concentrations.

Aeric Duraquerts

Dystraquerts

Key to Subgroups

FAFA.  Dystraquerts that have, in one or more horizons within 100 cm of the mineral soil surface, jarosite concentrations and a pH value of 4.0 or less (1:1 water, air-dried slowly in shade).

Sulfaqueptic Dystraquerts

FAFB.  Other Dystraquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 210 or more cumulative days per year.

Aridic Dystraquerts

FAFC.  Other Dystraquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year.

Ustic Dystraquerts

FAFD.  Other Dystraquerts that have, in one or more horizons between either an Ap horizon or a depth of 25 cm from the mineral soil surface, whichever is deeper, and a depth of 75 cm,

50 percent or more colors as follows: 1.  Hue of 2.5Y or redder and either:

a.  Acolor value, moist, of 6 or more and chroma of 3 or more; or

b.  A color value, moist, of 5 or less and chroma of 2 or more; or

2.  Hue of 5Y and chroma of 3 or more; or

3.  Chroma of 2 or more and no redox concentrations.

Aeric Dystraquerts

FAFE.  Other Dystraquerts that have a densic, lithic, or paralithic contact within 100 cm of the mineral soil surface.

Leptic Dystraquerts

FAFF.  Other Dystraquerts that have a layer, 25 cm or more thick within 100 cm of the mineral soil surface, that contains less than 27 percent clay in its fine-earth fraction.

Entic Dystraquerts

FAFG.  Other Dystraquerts that have, in one or more horizons within 30 cm of the mineral soil surface, one or both of the following in more than half of each pedon:

1.  A color value, moist, of 4 or more; or

2.  Acolor value, dry, of 6 or more.

Chromic Dystraquerts

FAFH.  Other Dystraquerts.

Typic Dystraquerts

Endoaquerts

Key to Subgroups

FAHA.  Endoaquerts that have, throughout a layer 15 cm or more thick within 100 cm of the mineral soil surface, an

electrical conductivity of 15 dS/m or more (saturated paste) for

6 or more months in normal years.

Halic Endoaquerts

FAHB.  Other Endoaquerts that have, in one or more horizons within 100 cm of the mineral soil surface, an exchangeable sodium percentage of 15 or more (or a sodium adsorption ratio of 13 or more) for 6 or more months in normal years.

Sodic Endoaquerts

FAHC.  Other Endoaquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 210 or more cumulative days per year.

Aridic Endoaquerts

FAHD.  Other Endoaquerts that have a thermic, mesic, or frigid soil temperature regime and that, if not irrigated during the year, have cracks in normal years that remain both:

1.  5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 60 or more

consecutive days during the 90 days following the summer solstice; and

2.  Closed for 60 or more consecutive days during the 90 days following the winter solstice.

Xeric Endoaquerts

FAHE.  Other Endoaquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year.

Ustic Endoaquerts

FAHF.  Other Endoaquerts that have, in one or more horizons between either an Ap horizon or a depth of 25 cm from the mineral soil surface, whichever is deeper, and a depth of 75 cm,

50 percent or more colors as follows: 1.  Hue of 2.5Y or redder and either:

a.  Acolor value, moist, of 6 or more and chroma of 3 or more; or

b.  A color value, moist, of 5 or less and chroma of 2 or more; or

2.  Hue of 5Y and chroma of 3 or more; or

3.  Chroma of 2 or more and no redox concentrations.

Aeric Endoaquerts

FAHG.  Other Endoaquerts that have a densic, lithic, or paralithic contact within 100 cm of the mineral soil surface.

Leptic Endoaquerts

FAHH.  Other Endoaquerts that have a layer, 25 cm or more thick within 100 cm of the mineral soil surface, that contains less than 27 percent clay in its fine-earth fraction.

Entic Endoaquerts

FAHI.  Other Endoaquerts that have, in one or more horizons within 30 cm of the mineral soil surface, one or both of the following in more than half of each pedon:

1.  A color value, moist, of 4 or more; or

2.  Acolor value, dry, of 6 or more.

Chromic Endoaquerts

FAHJ.  Other Endoaquerts.

Typic Endoaquerts

Epiaquerts

Key to Subgroups

FAGA.  Epiaquerts that have, throughout a layer 15 cm or more thick within 100 cm of the mineral soil surface, an

V E R

electrical conductivity of 15 dS/m or more (saturated paste) for

6 or more months in normal years.

Halic Epiaquerts

FAGB.  Other Epiaquerts that have, in one or more horizons within 100 cm of the mineral soil surface, an exchangeable sodium percentage of 15 or more (or a sodium adsorption ratio of 13 or more) for 6 or more months in normal years.

soil temperature regime and that, if not irrigated during the year, have cracks in normal years that remain both:

1.  5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 60 or more consecutive days during the 90 days following the summer solstice; and

2.  Closed for 60 or more consecutive days during the 90 days following the winter solstice.

Xeric Epiaquerts

FAGE.  Other Epiaquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year.

Ustic Epiaquerts

FAGF.  Other Epiaquerts that have, in one or more horizons between either an Ap horizon or a depth of 25 cm from the mineral soil surface, whichever is deeper, and a depth of 75 cm,

50 percent or more colors as follows: 1.  Hue of 2.5Y or redder and either:

a.  Acolor value, moist, of 6 or more and chroma of 3 or more; or

b.  A color value, moist, of 5 or less and chroma of 2 or more; or

2.  Hue of 5Y and chroma of 3 or more; or

3.  Chroma of 2 or more and no redox concentrations.

Aeric Epiaquerts

FAGG.  Other Epiaquerts that have a densic, lithic, or paralithic contact within 100 cm of the mineral soil surface.

Leptic Epiaquerts

FAGH.  Other Epiaquerts that have a layer, 25 cm or more thick within 100 cm of the mineral soil surface, that contains less than 27 percent clay in its fine-earth fraction.

Entic Epiaquerts

FAGI.  Other Epiaquerts that have, in one or more horizons within 30 cm of the mineral soil surface, one or both of the following in more than half of each pedon:

1.  A color value, moist, of 4 or more; or

2.  Acolor value, dry, of 6 or more.

Chromic Epiaquerts

FAGJ.  Other Epiaquerts.

Typic Epiaquerts

Natraquerts

Key to Subgroups

FADA.  All Natraquerts.

Typic Natraquerts

Salaquerts

Key to Subgroups

FABA.  Salaquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 210 or more cumulative days per year.

Aridic Salaquerts

FABB.  Other Salaquerts that, if not irrigated during the year, have cracks in normal years that are 5 mm or more wide, through a thickness of 25 cm or more within 50 cm of the mineral soil surface, for 90 or more cumulative days per year.

Ustic Salaquerts

FABC.  Other Salaquerts that have a densic, lithic, or paralithic contact within 100 cm of the mineral soil surface.

Leptic Salaquerts

FABD.  Other Salaquerts that have a layer, 25 cm or more thick within 100 cm of the mineral soil surface, that contains less than 27 percent clay in its fine-earth fraction.

Entic Salaquerts

FABE.  Other Salaquerts that have, in one or more horizons within 30 cm of the mineral soil surface, 50 percent or more colors as follows:

1.  A color value, moist, of 4 or more; or

V E R

2.  Acolor value, dry, of 6 or more; or

3.  Chroma of 3 or more.

Chromic Calcitorrerts

FDCE.  Other Calcitorrerts.

Typic Calcitorrerts

Gypsitorrerts

Key to Subgroups

FDBA.  Gypsitorrerts that have, in one or more horizons within 30 cm of the soil surface, 50 percent or more colors as follows:

1.  A color value, moist, of 4 or more; or

2.  Acolor value, dry, of 6 or more; or

3.  Chroma of 3 or more.

Chromic Gypsitorrerts

FDBB.  Other Gypsitorrerts.

Typic Gypsitorrerts

Haplotorrerts

Key to Subgroups

FDDA.  Haplotorrerts that have, throughout a layer 15 cm or more thick within 100 cm of the soil surface, an electrical

conductivity of 15 dS/m or more (saturated paste) for 6 or more months in normal years.

Halic Haplotorrerts

FDDB.  Other Haplotorrerts that have, in one or more horizons within 100 cm of the soil surface, an exchangeable sodium percentage of 15 or more (or a sodium adsorption ratio of 13 or more) for 6 or more months in normal years.

Sodic Haplotorrerts

FDDC.  Other Haplotorrerts that have a densic, lithic, or paralithic contact or a duripan within 100 cm of the soil surface.

Leptic Haplotorrerts

FDDD.  Other Haplotorrerts that have a layer, 25 cm or more thick within 100 cm of the soil surface, that contains less than

27 percent clay in its fine-earth fraction.

Entic Haplotorrerts

1.  A color value, moist, of 4 or more; or

2.  Acolor value, dry, of 6 or more; or

3.  Chroma of 3 or more.

Chromic Haplotorrerts

FDDF.  Other Haplotorrerts.

Typic Haplotorrerts

Salitorrerts

Key to Subgroups

FDAA.  Salitorrerts that have, in one or more horizons within

100 cm of the soil surface, aquic conditions for some time in normal years (or artificial drainage) and either:

1.  Redoximorphic features; or

2.  Enough active ferrous iron to give a positive reaction to alpha,alpha-dipyridyl at a time when the soil is not being irrigated.

Aquic Salitorrerts

FDAB.  Other Salitorrerts that have a densic, lithic, or paralithic contact, a duripan, or a petrocalcic horizon within 100 cm of the soil surface.

Leptic Salitorrerts

FDAC.  Other Salitorrerts that have a layer, 25 cm or more thick within 100 cm of the soil surface, that contains less than

27 percent clay in its fine-earth fraction.

Entic Salitorrerts

FDAD.  Other Salitorrerts that have, in one or more horizons within 30 cm of the soil surface, 50 percent or more colors as follows:

1.  A color value, moist, of 4 or more; or

2.  Acolor value, dry, of 6 or more; or

3.  Chroma of 3 or more.

Chromic Salitorrerts

FDAE.  Other Salitorrerts.

Typic Salitorrerts

Uderts

Key to Great Groups

FDDE.  Other Haplotorrerts that have, in one or more horizons within 30 cm of the soil surface, 50 percent or more colors as follows:

FFA.  Uderts that have, throughout one or more horizons with a total thickness of 25 cm or more within 50 cm of the mineral soil surface, both: