GANGJIN SERIES

Established Series PCS, JYH 19 May, 1978

  The Gangjin series are members of the fine silty, mixed, mesic family of Anthraquic Eutrudepts [Fluvic Hydragric Anthrosols (Eutric Siltic) classified by WRB]. These soils have gray silt loam Ap1 horizons with yellowish brown mottles, gray silt loam Ap2 horizons with strong brown mottles, gray silty clay loam BAg horizons with dark yellowish brown mottles, dark yellowish brown silty clay loam Bw horizons with yellowish brown mottles, and strong brown silty clay loam BC horizons with yellowish brown mottles. They occur on local valleys derived from mainly porphyry rocks.

Typifying Pedon: Gangjin silt loam-paddy rice (Colors are for moist soil).

  Slope: 2-7%

  Elevation: 21 m above m.s.l.

  Soil moisture regime: Udic

  Soil temperature regime: Mesic

  Parent material: All-colluvium from porphyry

  Diagnostic features: An ochric epipedon from a depth of 0 to 22 cm and a cambic horizon from a depth of 42 to 71 cm (An anthraquic horizon from a depth of 0 to 42 cm and a hydragric horizon from a depth of 42 to 71 cm by WRB).

  Described by: Song, K. C., S. J. Jung, and D. C. Noh,  17 Nov., 2010.

Morphological properties of typifying pedon.

Ap1 - 0 to 13 cm. Gray (10YR 5/1) silt loam; common fine to medium prominent yellowish brown (10YR 5/6) mottles; structureless, puddled; sticky and plastic; many fine to medium roots; common fine to medium pores; abrupt smooth boundary.

Ap2 - 13 to 22 cm. Gray (2.5Y 5/1) silt loam; common fine prominent strong brown (7.5YR 4/6) mottles; moderate fine to medium subangular blocky structure; firm, sticky and plastic; thin patch clay cutans; few fine roots; common fine pores; clear smooth boundary.

BAg - 22 to 42 cm. Gray (2.5Y 5/1) silty clay loam; common fine to medium prominent dark yellowish brown (10YR 4/4) mottles; moderate fine to medium subangular blocky structure; firm, sticky and plastic; thin continuous clay cutans; few fine roots; common fine pores; common fine micas; few Mn mottles; clear smooth boundary.

Bw - 42 to 71 cm. Dark yellowish brown (10YR 3/4) silty clay loam; common fine to medium distinct yellowish brown (10YR 5/6) mottles; moderate medium to coarse subangular blocky structure; firm, sticky and plastic; thick continuous clay cutans; no roots; common fine pores; common Mn mottles; few worm holes; clear smooth boundary.

BC - 71 to 160 cm. Strong brown (7.5YR 4/6) silty clay loam; few fine distinct yellowish brown (10YR 5/4) mottles; moderate medium to coarse subangular blocky structure; firm, sticky and plastic; thick continuous clay cutans; common fine to medium pores; few Mn mottles; moderate medium to coarse worm holes.

  The typifying pedon has an ochric epipedon from a depth of 0 to 22 cm, a cambic horizon from a depth of 42 to 71 cm. That can be classified as Inceptisol. It is used for paddy field, but does not have aquic conditions for some time in normal years in a layer at a depth between 40 and 50 cm from the mineral soil surface. Therefore it can be classified as Udept. It has a base saturation (by NH4OAc) of 60% or more in one or more horizons at a depth between 25 and 75 cm from the mineral soil surface. That keys out as Eutrudept. It has anthraquic conditions and can be classified as Anthraquic Eutrudept.

  The typifying pedon has in the fraction less than 75 mm in diameter, less than 15% particles with diameters of 0.1 to 75 mm and in the fine-earth fraction, 18 to 35% clay at the particle-size control section and has mesic soil temperature regime. Therefore it can be classified as fine silty, mixed, mesic family of Anthraquic Eutrudept.

Type Location: About 600 meters east of the Manboghoegwan, Yeongbog Ri, Chilryang Myeon, Gangjin Gun, Jeollanam Do (126^o 47' 42.9'', 34^o 34' 39.8'').

Range in Characteristics: These soils have ochric epipedons and cambic horizons. The solum thickness ranges from 100 to 200 cm. Depth to hard rock is more than 3 meters. Reaction is strongly acid in the upper part; slightly acid in the lower part of the profile. Ap horizons are dark gray, grayish brown, olive gray, or dark grayish brown silt loam with dark brown, dark reddish brownor yellowish brown mottles. Bw horizons are yellowish brown, brown, dark brown,or strongbrown silt loam or silty clay loamwith light olive brown or olive gray mottles.

Competing Series and Their Differentiae: These are the Yulgog, Simcheon, and Juggog soils.  The Yulgog soils are derived from limestone materials. The Simcheon soils are on broad alluvial plains derived from alluvial materials. The Juggog soils are fine loamy texture family and derived from red shale materials.

Setting: The Gangjin soils occur on local valley and mountain foot slopes mainly derived from porphyry. The dominant slope is 2 to 7 percent and ranges form 2 to 30 percent.

Principal Associated Soils: Th Pangog soils are associated in similarphysiographic positions. The Gagog and Jindo soils are associated in lower positions. The Bongsan and Nasan soils are in rolling to hilly areas.

Drainage and Permeability: Moderately well drained; moderate or slow permeability; moderate or rapid runoff.

Use and Vegetation: These soils are used for paddy field.

Distribution and Extent: The Gangjin soils are of mall extent distributed on porphyry geology in the southern parts of the country.

Series Established: Gangjin Gun, Jeollanam Do, 1975. Revised, Gangjin Gun, Jeollanam Do, 2010.

Laboratory data sheets of typifying pedon.

Depth (cm)	Horizon	( --- Total ---)			(-- Clay --)		(-- Silt --)		(------- Sand -------)
		Clay	Silt	Sand	Fine	Coarse	Fine	Coarse	VF	F	M	C	VC
		LT	.002	.05	LT	LT	.002	.02	.05	.10	.25	.5	1
		.002	- .05	- 2	.0002	.002	- .02	- .05	- .10	- .25	- .50	- 1	- 2
		- - - - - - - - - - - Pct of ˂ 2mm (3A1) - - - - - - - - - - -
0-13	Ap1	31.7	51.2	17.1			22.8	28.4	2.1	3.4	3.5	4.7	3.3
13-22	Ap2	32.3	49.3	18.3			19.8	29.5	2.2	3.7	3.9	4.9	3.6
22-42	Bg1	31.9	50.0	18.1			17.8	32.3	2.0	3.6	4.0	5.0	3.5
42-71	Bg2	26.5	55.2	18.2			17.2	38.2	2.4	4.2	4.3	4.4	2.9
71-160	BCg	34.5	50.3	15.2			15.6	34.6	4.0	4.3	3.1	2.7	1.2

Depth (cm)

Coarse Fractions(mm)

˃2mm

Orgn

Total

Extr

Total

(-- Dith -Cit --)

Weight

Wt

C

N

P

S

Extractable

2-5

5-20

20-75

.1-75

Pct of

Fe

Al

Mn

Whole

6A1c

6B3a

6S3

6R3a

6C2b

6G7a

6D2a

Pct of ˂ 75mm (3B1)

Soil

Pct ˂ 2mm

g/kg

Pct of ˂ 2mm

0-13

0.99

13-22

0.34

22-42

0.10

42-71

0.31

71-160

0.13

Depth (cm)

Ratio/Clay

Atterberg

( Bulk Density )

COLE

(- Water Content -)

WRD

CEC

1500

Limits

Field

33

Oven

Whole

Field

10

33

1500

Whole

kPa

LL

PI

Moist

kPa

Dry

Soil

Moist

kPa

kPa

kPa

Soil

8D1

8D1

4P1

4P

4A3a

4A1d

4A1h

4D1

4B4

4B1c

4B1c

4B2a

4C1

Pct ˂0.4mm

- - g/cc - -

cm/cm

-- Pct of ˂2mm --

cm/cm

0-13

0.41

1.07

30.4

13-22

0.35

1.44

27.4

22-42

0.39

1.57

23.8

42-71

0.56

1.53

23.2

71-160

0.41

Depth (cm)	( NH4OAc Extractable Bases )					Acid-	Extr	(----- CEC -----)			Al
	Ca	Mg	K	Na	Sum	ity	Al	Sum	NH4-	Bases	Sat
	5B5a	5B5a	5B5a	5B5a	Bases			Cats	OAc	+ Al
	6N2e	6O2d	6Q2b	6P2b		6H5a	6G9a	5A3a	5A8b	5A3b	5G1
	- - - - - - - - - - - - meq / 100g - - - - - - - - - - - -										Pct
0-13	3.1	1.0	0.4	0.1	5.5	19.7	3.5	24.2	12.9	8.0	43.6
13-22	4.5	1.8	0.3	0.1	6.7	15.4	0	22.0	11.2	6.7	0
22-42	5.3	2.1	0.2	0.2	7.8	13.4	0	21.2	12.3	7.8	0
42-71	5.3	1.8	0.2	0.1	7.4	15.0	0	22.4	14.9	7.4	0
71-160	5.1	1.7	0.1	0.2	7.2	13.9	0	21.0	14.1	7.2	0

Depth (cm)	(Base Sat)		CO3 as	Res	Cond	(------ pH ------)				Acid Oxalate Extraction
	Sum	NH4-	CaCO3			NaF	KCl	CaCl2	H2O	Opt	Al	Fe	Si
		OAc	˂2mm					.01M		Den
	5C3	5C1	6E1g	8E1	8I	8C1d		8C1f	8C1f	8J	6G12	6C9a	6V2
	---- Pct ----			ohms/cm	dS/m		1: 1	1: 2	1: 1		- Pct of ˂2mm -
0-13	18.6	34.9					4.3	4.7	5.3
13-22	30.4	59.8					5.0	5.3	6.0
22-42	36.9	63.4					5.4	5.9	6.4
42-71	33.0	49.7					5.1	5.5	6.2
71-160	34.1	51.1					5.1	5.6	6.1