DAEBON SERIES

Established Series PCS, JYH 12 June, 1977

  The Daebon series are members of the sandy skeletal, mixed, mesic family of Typic Udorthents [Haplic Regosols (Eutric Skeletic) classified by WRB]. These soils have thin, brown to dark brown very gravelly loamy sand A horizons and light yellowish brown very gravelly loamy sand C horizons. These soils occur on beach dunes deposited by wind and sea water.

Typifying Pedon : Daebon gravelly loamy fine sand-wild grass (Field description Yeongil Gun profile No. 72; colors are for moist soil).

  Slope: 2-7%

  Elevation:  m above m.s.l.

  Soil moisture regime: Udic

  Soil temperature regime: Mesic

  Parent material: Alluvium from beach sand

  Diagnostic features: An ochric epipedon from a depth of 0 to 20 cm.

Morphological properties of typifying pedon.

A - 0 to 20 cm. Brown (10YR 4/3) very gravelly loamy sand; structureless, single grained; loose, non sticky and non plastic; many fine wild grass roots; about 40 percent of fine gravels; gradual smooth boundary.

C1 - 20 to 70 cm. Brown (10YR 5/3) very gravelly loamy sand; structureless, single grained; loose, non sticky and non plastic; many fine roots; about 60 percent of round gravels; gradual smooth boundary.

C2 - 70+ cm. Brown (10YR 5/3) very gravelly sand; structureless, single grained; loose, non sticky and non plastic; about 80 percent of round gravels.

Type Location: About 5 meters south east of Dasan Primary School, Nae Ri, Yangnam Myeon, Gyeongju city, Gyeongsangbug Do.

Range in Characteristics: These soils have ochric epipedons. The depth to bed rock is more than 3 meters. Reaction is medium acid. Base saturation is more than 60 percent. The thickness of A horizon ranges from 5 to 15 cm. A horizons are brown, brown to dark brown, dark yellowish brown or light yellowish brown gravelly fine sand, loamy sand, loamy fine sand, sand and gravelly sandy loam. C horizons are brown, light yellowish brown, yellowish brown, pale brown very gravelly loamy sand and sand. More than 35 percent of well round gravels occur throughout the profiles and their contents increase with depth.

Competing Series and Their Differentiae: These are the Haeri, Gapa, and Hwangryong soils. The Haeri soils are sandy texture family and the Gapa soils contain sea shell fragments. The Hwangryong soils occur on continental alluvial plains.

Setting: The Daebon soils occur on beach ridge and beach dune areas deposited by wind and sea water action. The slope range is 2 to 15 percent. The dominant slope is 2 to 7 percent.

Principal Associated Soils: The Haeri, Yeondae and Hajeong soils are associated. The Haeri soils are in coastal plains, the Yeondae soils in higher mountain foot slope positions, and the Hajeong soils in higher rolling to hilly areas.

Drainage and Permeability: Somewhat excessively drained and very rapid permeability. Runoff is slow to medium.

Use and Vegetation: Most of these soils are forest.

Distribution and Extent: The Daebon soils are of small extent and mainly distributed on the east coastal areas of the country.

Series Established: Yeongil Gun, Gyeongsangbug Do, 1976.

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) - - - - - - - - - - -
0-20	A	0.4	4.1						0.2	4.0	16.7	31.5	43.1
20-70	C1	0.2	4.3						0.8	7.2	14.0	24.0	49.5
70+	C2	0.1	3.6						0.2	0.8	11.0	35.5	48.8

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

0-20

0.56

20-70

0.56

70+

0.40

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

0-20

5.6

4.0

2.4

20-70

-

6.9

4.9

2.7

70+

-

4.6

3.6

2.2

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
0-20	1.12	0.60	0.11	0.19					4.00
20-70	2.28	1.03	0.13	0.24					3.90
70+	2.05	0.78	0.11	0.20					3.85

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 -

0-20

50.5

3.9

5.4

20-70

94.4

4.5

5.8

70+

81.6

4.6

6.0