LOCATION NIKOLAEVSK                  AK

Tentative Series                                                                        DRAFT

DVP   

10/99

NIKOLAEVSK SERIES

The Nikolaevsk series consists of very deep, poorly drained soils formed in a mantle of volcanic ash and loess deposits overlying coarse reworked glacial till.  Nikolaevsk soils are on kame moraines and lateral moraines.  Slopes range from 0 to 15 percent.  The mean annual temperature is about 35 degrees F. and the mean annual precipitation is about 30 inches.  

TAXONOMIC CLASS: Medial over sandy or sandy-skeletal, amorphic Andic Cryaquods

TYPICAL PEDON: Nikolaevsk silt loam, on a northwest-facing, convex, 6 percent slope under Lutz spruce forest at 402 meters elevation.  (All colors are for moist soil, textures are apparent field textures)

      Oi—0 to 5 cm; black (10YR 2/1) fibrous litter; abrupt smooth boundary. (4 to 8 cm thick)

      E—5 to 7 cm; very dark grayish brown (10YR 4/2) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; common very fine, fine, and few medium roots; smeary; very strongly acid; abrupt broken boundary.  (2 to 5 cm thick)

      Bhs—7 to 10 cm; very dark brown (7.5YR 2.5/3) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; common very fine, fine, and few medium roots; smeary; very strongly acid; abrupt broken boundary. (3 to 6 cm thick)

      Eb—10 to 14 cm; dark brown (7.5YR 3/2) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; common very fine, fine, and few medium roots; smeary; very strongly acid; abrupt wavy boundary.  (2 to 5 cm thick)

      Bhsb—14 to 32 cm; dark reddish brown (5YR 2.5/2) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; common very fine and fine roots; very smeary; very strongly acid; abrupt wavy boundary. (8 to 20 cm thick)

      Bw—32 to 62 cm; olive brown (2.5Y 4/3) silt loam; weak fine granular structure; very friable, nonsticky and nonplastic; few very fine and fine roots; very smeary; 5 percent 2 mm brown (7.5YR 4/4) high chroma concentrations and 5 percent 3 mm dark grayish brown (2.5Y 4/2) low chroma depletions; very strongly acid; abrupt wavy boundary. (22 to 35 cm thick)

       2C—62 to 150 cm; very dark gray (5Y 3/1) and dark gray (5Y 4/1) very cobbly loamy sand; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; slightly smeary; 20 percent gravel, 30 percent cobble, and 5 percent stone; moderately acid. 

TYPE LOCATION:  Western Kenai Peninsula Area, Alaska; ½  mile northwest of Caribou Lake; 2400 feet west and 500 feet north of the southeast corner of section 13, T. 3S, R. 11W., USGS Seldovia D-3 quadrangle; UTM Zone 5 coordinates 606589 E. 6642903 N., NAD 27 Alaska.

RANGE IN CHARACTERISTICS:  Mean annual soil temperature ranges from 33 to 37 degrees F.  Depth to glacial till ranges from 36 to 80 cm.  The loess mantle is dominated by volcanic ash and has moist bulk density of less than 0.9 grams per cubic centimeter and phosphorous retention greater than 85 percent.  The weighted average particle size of the contrasting substratum material is sandy.  Reaction ranges from very strongly acid to moderately acid in the solum and moderately acid to slightly acid in the substratum.

The E horizon has moist hue of 10YR; value moist of 4 or 5; and chroma moist of 1 or 2.  Texture is silt loam or very fine sandy loam.

The Bhs and Bhsb horizons have moist hue of 5YR or 7.5YR; value moist of 2.5 or 3; chroma moist of 2 or 3. 

The Bs horizon, when present, has moist hue of 10YR; value moist of 3 or 4; chroma moist of 4 to 6.  Texture is silt loam and very fine sandy loam.

The Bw and Bwb horizons have moist hue of 10YR or 2.5Y; value moist of 3 or 4; chroma moist of 2 to 4.  Texture is silt loam and very fine sandy loam.

The Bg horizon, when present, has hue of 2.5Y; value moist of 3 or 4; chroma moist of 2 to 4.  Texture is silt loam, very fine sandy loam, or fine sandy loam.

The 2Cg horizon has hue of 5Y or 2.5Y; value moist of 3 or 4; chroma moist of 1 to 4.  Texture is sand, loamy sand, and loamy fine sand.  Coarse fragment content ranges from 15 to 40 percent gravel, 10 to 35 percent cobble, and 1 to 15 percent stone.

COMPETING SERIES: This is the Spenard series.  Spenard soils have loamy textures in the lower part of the control section.

GEOGRAPHIC SETTING:  Nikolaevsk soils are on lateral moraines, kame moraines, and kame terraces.  They formed in a loess mantle dominated by volcanic ash overlying coarse reworked glacial till. Slopes are 0 to 15 percent. Elevations are 300 to 500 meters.  The climate is transitional maritime-continental.  Mean annual temperature is about 35 degrees F. and mean annual precipitation is about 30 inches.

GEOGRAPHICALLY ASSOCIATED SOILS:  These are the Puntilla and Tuxedni soils.  Puntilla soils have loamy C horizons with less than 35 percent rock fragments and are on nunataks.  Tuxedni soils do not have spodic horizons, have redoximorphic features below 50 cm, and are on better drained positions of moraines.

DRAINAGE AND PERMEABILITY:  Poorly drained.  Slow to medium runoff.  Moderate permeability in the loess mantle and rapid in the underlying glacial till.

USE AND VEGETATION:  These soils are used for wildlife habitat.  The native vegetation includes stunted Lutz spruce and mixed shrubs, forbs, and grass.

DISTRIBUTION AND EXTENT:  Southcentral Alaska.  The series is of limited extent.

MLRA OFFICE RESPONSIBLE: Anchorage, Alaska

SERIES ESTABLISHED:  (proposed)  Western Kenai Peninsula Soil Survey, Alaska. 1999. (99SS142-01)

REMARKS:  Diagnostic horizons and features recognized in this profile include: assumed > 2.0 cmol(+)/kg AL 3+ in the solum; andic soil material from 5 to 62 cm; redoximorphic features between 32 and 152 cm; sandy or sandy skeletal particle size from 62 to 150 cm; cryic temperature regime.

National Cooperative Soil Survey

U.S.A.

Contact: Mike Gracz Kenai Watershed Forum  PO Box 15301 Fritz Creek, AK  99603 907-235-2218

04 May 2007 10:18