All Issue

2025 Vol.58, Issue 1 Preview Page

Opinion

Quantitative classification of ‘excessively drained’ and ‘somewhat excessively drained’ of Korean soils using soil properties
Danbi Lee1
,
Byeong Hwan Seo1
,
SongRae Cho1
,
WooRi Go1
,
MinSan Im1
,
Yeon Kyu Sonn2*
1Researcher, Soil & Fertilizer Management Division, Department of Agricultural Environment, National Institute of Agricultural Science, Rural Development Administration Wanju 55365, Korea
2Senior Researcher, Soil & Fertilizer Management Division, Department of Agricultural Environment, National Institute of Agricultural Science, Rural Development Administration Wanju 55365, Korea
*Corresponding Author
28 February 2025. pp. 144-150
PDF XML Citation
Abstract

The classification of soil drainage is broadly defined based on internal soil drainage and permeability, as well as relationships with soil color mottles, the location of mottles, groundwater level, soil texture, parent material, and topography. In Korea, soil drainage classes are defined as ‘somewhat excessively drained,’ ‘well drained,’ ‘moderately well drained,’ ‘somewhat poorly drained,’ and ‘poorly drained.’ However, the classification criteria for ‘excessively drained’ and ‘somewhat excessively drained’ in Korea are currently not quantified, making them ambiguous. Therefore, this study aims to classify soil series distributed in Korea into drainage classes such as ‘excessively drained’ and ‘somewhat excessively drained’, which currently lack clear classification criteria. The study follows the Soil Survey Manual and proposes quantified classification criteria based on soil characteristics. According to the Soil Survey Manual, ‘somewhat excessively drained’ is defined as ‘water is removed very rapidly or rapidly, consisting of coarse-textured soil with very high saturated hydraulic conductivity or very shallow effective soil depth.’ Quantitatively, this is classified as coarse-textured soil (Clay < 15%, Silt < 30%, and Sand ≥ 70%) with very high or high saturated hydraulic conductivity or very shallow effective soil depth (< 25 cm). Based on these criteria, forest soils in Korea were classified, and it was confirmed that some forest soils were misclassified. The proposed quantitative criteria for drainage classes are expected to be widely utilized by researchers for direct classification, moving away from traditional reliance on survey experts. These criteria are also expected to contribute to field farming guidance and the development of soil management strategies. Furthermore, correcting misclassified soils is essential to improve the accuracy of soil suitability ratings for crops.

A quantitative criterion for soil drainage class classification.
Class Criteria
Excessively drained Coarse texture (Clay < 15%, Silt < 30%, and sand ≥ 70%), very high saturated hydraulic conductivity, very shallow Root-Restricting Depth (< 25cm) New criteria
Somewhat excessively drained Coarse texture (Clay < 15%, Silt < 30%, and sand ≥ 70%), high saturated hydraulic conductivity, very shallow Root-Restricting Depth (< 25cm)
Well drained Each horizon has only one color (except lithological color), and mottles < 2% Sonn et al.(2020)
Moderately well drained Mottles (more higher value, less lower chroma than main color) are 0 - 49% on any one of the layers
Somewhat poorly drained 20 ≤ ground water level < 50 cm, main color is grayish, 2 ≤ mottles (by oxidation) < 50% in 20 - 50 cm from soil surface
Poorly drained 20 ≤ ground water level < 50 cm, main color is grayish, mottles (by oxidation) < 2% in 20 - 50 cm from soil surface
Very poorly drained ground water level < 20 cm, main color is grayish, mottles (by oxidation) < 2% in 0 - 20 cm from soil surface
Keywords
Drainage class
Soil color
Soil series
Soil texture
Soil classification
References
1

Andre CD, Jose AMD, Raphael AVR, Rodnei R. 2020. Soil environment grouping system based on spectral, climate, and terrain data: a quantitative branch of soil series. J. Soil. 6:163-177. https://doi.org/10.5194/soil-6-163-2020.

10.5194/soil-6-163-2020
2

Cho SR, Go WR, Seo BH, Lee DB, Sonn YK. 2023. Establishment of soil suitability for growing bracken (Pteridium aquilinum L.) using the quantification theory I. J. Korean Soc. Soil Sci. Fert. 56:109-118. https://doi.org/10.7745/KJSSF.2023.56.1.109

10.7745/KJSSF.2023.56.1.109
3

Hur SO, Sonn YK, Lee KJ, Lee ST, Park CW, Jeon SH, Ha SK, Kim JG. 2008. Water movement characteristics by soil horizon of cumulants Anthrosol in highland. p. 132. In Proceedings of the Korean Society of Soil Science and Fertilizer Conference, Seoul, Korea.

4

IUSS Working Group WRB. 2022. World reference base for soil resources: International soil classification system for naming soils and creating legends for soil maps (4th ed.). International Union of Soil Sciences (IUSS), Vienna, Austria.

5

Jung KH, Sonn YK, Hur SO, Ha SK, Jung MH. 2015. Hydraulic characteristics of mountainous forest soils in Korea and applicability of pedotransfer functions. J. Korean Soc. Soil Sci. Fert. 48:428-435. https://doi.org/10.7745/KJSSF.2015.48.5.428.

10.7745/KJSSF.2015.48.5.428
6

Jung YT, Jung SJ, Hyeon GS, Sonn YK, Cho YK, Yun ES, Cho GH. 2001. Classification of morphological types of the korean paddy soils for practical use of soil survey results. J. Korean Soc. Soil Sci. Fert. 34:77-84.

7

Jung YT, Son IS, Yun ES, Sonn YK, No YP. 1996. Tentative suitability criteria for the consolidation of cultivated upland in korea. J. Korean Soc. Soil Sci. Fert. 29:81-85.

8

Lee DB, Kim YN, Sonn YK, Kim KH. 2023b. Comparison of soil taxonomy (2022) and WRB (2022) systems for classifying paddy soils with different drainage grades in South Korea. Land. 12:1204. https://doi.org/10.3390/land12061204

10.3390/land12061204
9

Lee DB, Seo BH, Go WR, Cho SR, Sonn YK. 2023a. Comparison among soil taxonomy (2014), WRB (2014), and WRB (2022) systems on anthropogenic soils in Korea. J. Korean Soc. Soil Sci. Fert. 56:68-76. https://doi.org/10.7745/KJSSF.2023.56.1.068

10.7745/KJSSF.2023.56.1.068
10

NAAS (National Academy of Agricultural Science). 2014. Taxonomical classification of Korean soil. RDA, Suwon, Korea.

11

NIAST (National Institute of Agricultural Science and Technology). 1973. Soil Survey Manual: Field Investigation and Classification (No. 1). RDA. Suwon, Korea.

12

Soil Science Division Staff. 2017. Soil survey manual. Agriculture Handbook No. 18. USDA-NRCS, Washington DC, USA.

13

Soil Survey Staff. 2014. Keys to Soil Taxonomy Twelfth Edition. USDA-NRCS (United States Department of Agriculture-Natural Resources Conservation Service). Washington DC, USA.

14

Sonn YK, Seo BH, Go WR, Jeon SH, Hyun BK, Yun SK. 2019. Consideration of suffix symbol on soil taxonomy and world reference base for soil resources classification. Korean J. Soil Sci. Fert. 52:345-351. https://doi.org/10.7745/KJSSF.2019.52.4.345

10.7745/KJSSF.2019.52.4.345
15

Sonn YK, Seo BH, Go WR, Jeon SH. 2020. Quantification of drainage classes of Korean soils as morphological characteristics. Korean J. Soil Sci. Fert. 53:668-676. https://doi.org/10.7745/KJSSF.2020.53.4.668

10.7745/KJSSF.2020.53.4.668
Information
  • Publisher :Korean Society of Soil Science and Fertilizer
  • Publisher(Ko) :한국토양비료학회
  • Journal Title :Korean Journal of Soil Science and Fertilizer
  • Journal Title(Ko) :한국토양비료학회 학회지
  • Volume : 58
  • No :1
  • Pages :144-150
  • Received Date : 2024-11-08
  • Revised Date : 2024-12-17
  • Accepted Date : 2024-12-26
  • DOI :https://doi.org/10.7745/KJSSF.2025.58.1.144
Journal Informaiton Korean Journal of Soil Science and Fertilizer Korean Journal of Soil Science and Fertilizer
KJSSF Online Submission
  • NRF
  • KOFST
  • crossref crossmark
  • crossref cited-by
  • crosscheck
  • orcid
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close