The Seungju series are members of the fine, mixed, mesic family of Typic Endoaqualfs [Gleyic Hydragric Anthrosols (Eutric Siltic) classified by WRB]. These soils have dark gray silt loam Ap horizons with strong brown mottles, dark gray silty clay loam BAg horizons with strong brown mottles, dark gray silty clay loam Btg1 horizons with strong brown mottles, gray silty clay Btg2 horizons with brown and olive brown mottles, and dark gray silty clay Cg horizons with dark yellowish brown mottles. These soils are on fluvio-marine plains.

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

  Slope: 0-2%

  Elevation: 2 m above m.s.l.

  Soil moisture regime: Aquic

  Soil temperature regime: Mesic

  Parent material: Alluvium from fluvio-marine

  Diagnostic features: An ochric epipedon from a depth of 0 to 18 cm and an argillic horizon from a depth of 33 to 95 cm (An anthraquic horizon from a depth of 0 to 33 cm and a hydragric horizon from a depth of 33 to 95 cm by WRB).

  Described by: Song, K. C., D. C. Noh, and B. K. Hyun,  7 March, 2012.

Morphological properties of typifying pedon.

Ap - 0 to 18 cm. Dark gray (10YR 4/1) silt loam; common fine to medium prominent strong brown (7.5YR 5/6) mottles; weak coarse platy structure; slightly firm, slightly sticky and plastic; common fine to medium roots; few medium pores; gradual smooth boundary.

BAg - 18 to 33 cm. Dark gray (10YR 4/1) silty clay loam; common fine to medium prominent strong brown (7.5YR 5/6) mottles; weak coarse prismatic structure; firm, sticky and plastic; thin continuous clay cutans; few fine to medium roots; common medium pores; few medium Mn mottles; clear smooth boundary.

Btg1 - 33 to 55 cm. Dark gray (10YR 4/1) silty clay loam; common fine to medium prominent strong brown (7.5YR 5/6) mottles; weak coarse prismatic  structure; slightly firm, sticky and plastic; thin continuous clay cutans; few fine roots; few coarse pores; many fine to coarse Mn mottles; clear smooth boundary.

Btg2 - 55 to 95 cm. Gray (2.5Y 5/1) silty clay; common medium to coarse prominent brown (7.5YR 5/4) and olive brown (2.5Y 4/4) mottles; weak coarse prismatic structure; puddled, very sticky and very plastic; thick continuous clay cutans; no roots; few medium pores; few weed stems; clear smooth boundary.

Cg - 95 to 160 cm. Dark gray (5Y 4/1) silty clay; few coarse prominent dark yellowish brown (10YR 4/6) mottles; structureless, puddled; very firm, very sticky and very plastic; thin patch clay cutans; no pores.

  The typifying pedon has an ochric epipedon from a depth of 0 to 18 cm, an argillic horizon from a depth of 33 to 95 cm, and a base saturation (by sum of cations) of 35% or more at 125 cm below the upper boundary of the argillic horizon. That can be classified as Alfisol. It has aquic conditions for some time in normal years in one or more horizons within 50 cm of the mineral soil surface, and has redoxmorphic features in all layers between a depth of 25 and 40 cm from the mineral soil surface and within the upper 12.5 cm of the argillic horizon, 50% or more redox depletions with chroma of 2 of less on the faces of peds and redox concentrations within peds. Therefore it can be classified Aqualf. It has endosaturation and keys out as Endoaqualf. Also it meets the requirements of Typic Endoaqualf.

  The typifying pedon has fine particle-size class and mesic soil temperature class. Therefore it can be classified as fine, mixed, mesic family of Typic Endoaqualf.

Type Location: About 1,000 meters west of the Haeryong Elementary School, Woljeon Ri, Haeryong Myeon, Suncheon city, Jeollanam Do (127° 31' 25.7'', 34° 54' 36.3'').

Range in Characteristics: These soils have ochric epipedons and argillic horizons. The solum thickness ranges from 50 to 100 cm. Depth to hard rock is probably more than 5 meters. The reaction is strongly to slightly acid. Base saturation is more than 60 percent. Ap horizons are grayish brown or dark grayish brown loam or silt loam with yellowish brown, brown, or yellowish red mottles. Bt horizons are grayish brown or gray silty clay loam with brown, yellowish brown, or light olive brown mottles. C horizons are dark gray or gray silty clay loam or silty clay with or without light olive brown mottles.

Competing Series and Their Differentiae: These are the Gimje, Sinpyeong, and Honam soils. The Buyong soils are imperfectly drained and fine clayey texture family. The Gimje soils have peaty mineral layers and are imperfectly drained. The Sinpyeong soils occur on low positions in broad continental alluvial plains near the fluvio-marine plains. The Honam soils occur on alluvial plains.

Setting: They are on level to nearly level in fluvio-marine plains derived from fluvio-marine materials. The dominant slope is 0 to 2 percent.

Principal Associated Soils: These are Buyong, Gimje, and Jeonbug soils in  similar positions.

Drainage and Permeability: Imperfectly drained; slow permeability; very slow runoff.

Use and Vegetation: The Seungju soils are used for paddy field.

Distribution and Extent: These soils are of small extent distributed on fluvio-marine plains in the southern parts of the country.

Series Established: Suncheon city, Jeollanam Do, 1977. Revised, Suncheon city, Jeollanam Do, 2012.

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) - - - - - - - - - - -
0-18	Ap	25.8	68.4	5.8			47.0	21.4	2.6	1.3	0.9	0.7	0.2
18-33	BAg	29.8	64.0	6.2			41.2	22.8	2.8	1.3	0.8	0.8	0.4
33-55	Btg1	35.9	59.0	5.2			41.8	17.2	1.0	1.3	1.3	1.1	0.5
55-95	Btg2	46.1	51.5	2.4			34.9	16.5	0.4	0.6	0.5	0.5	0.4
95-160	Cg	39.6	52.7	7.8			24.8	27.8	1.0	2.0	1.9	1.9	0.9

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

0-18

2.34

18-33

1.26

33-55

0.62

55-95

0.47

95-160

1.32

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

0-18

0.68

1.11

43.8

18-33

0.60

1.40

31.5

33-55

0.59

1.36

32.1

55-95

0.55

1.16

49.5

95-160

0.54

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
0-18	6.5	1.7		0.3	8.5	12.3	0.3	20.8	17.5	8.8	3.8
18-33	8.8	4.0		0.5	13.3	8.0	0	21.3	17.9	13.3	0
33-55	8.6	6.5		0.6	15.7	10.3	0	26.1	21.3	15.7	0
55-95	9.4	9.6		0.9	19.9	10.1	0	29.9	25.4	19.9	0
95-160	6.8	10.2		0.9	17.9	21.1	0.7	39.0	21.5	18.6	3.9

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 -
0-18	40.8	48.4					4.2	4.9	5.3
18-33	62.5	74.5					5.2	6.0	6.5
33-55	60.3	73.8					5.0	6.0	6.5
55-95	66.4	78.2					4.7	5.7	6.1
95-160	46.0	83.2					3.9	4.5	5.5