Page 12 - World Reference Base for Soil Resources of Thailand
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Land Development Department Library
4. Diagnostic horizons, properties and materials
Diagnostic horizons and properties are characterized by a combination of attributes
that reflect widespread, common results of the processes of soil formation or indicate
pecific conditions of soil formation. Diagnostic materials are materials that significantly influence
pedogenetic processes or are indicative of them. (Table 1-3)
Table 1 Diagnostic horizons
Diagnostic Horizons Diagnostic Horizons
1. Anthraquic horizon 20. Natric horizon
2. Argic horizon 21. Nitic horizon
3. Calcic horizon 22. Petrocalcic horizon**
4. Cambic horizon 23. Petroduric horizon**
5. Chernic horizon 24. Petrogypsic horizon**
6. Cryic horizon** 25. Petroplinthic horizon
7. Duric horizon 26. Pisoplinthic horizon
8. Ferralic horizon 27. Plaggic horizon**
9. Ferric horizon 28. Plinthic horizon
10. Folic horizon 29. Pretic horizon**
11. Fragic horizon 30. Protovertic horizon
12. Fulvic horizon** 31. Salic horizon
13. Gypsic horizon** 32. Sombric horizon
14. Histic horizon 33. Spodic horizon
15. Hortic horizon 34. Terric horizon**
16. Hydragric horizon 35. Thionic horizon
17. Irragric horizon 36. Umbric horizon**
18. Melanic horizon** 37. Vertic horizon
19. Mollic horizon
Remarks: ** not found in Thailand
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