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Concept, Key Identifying Features, Formation, Distribution and Land use of Aridisol, Andisol and Gelisol

1. University of Agricultural Sciences, Bangalore
Annappa, N. N.
Presentation By
Annappa, N. N.

2. ARIDISOLS
❑Thesearesoilsofdryplaces(aridandsemi-arid).
❑Thesoilsremaindryformostpartoftheyear,and
saltsaccumulateatthesurfaceand/orinthesolum,
resultinginthedevelopmentofasalicorcalcic
horizon.
Concept:

3. AridisolKey Identifying Features
a.An aridic soil moisture regime
b.An ochric epipedon with the upper boundary within 100
cm of the soil surface
c.A cambic horizon with its lower boundary at a depth of 25
cm or more;
d.A cryic temperature regime and a cambic horizon;
e.A calcic, gypsic, petrocalcic, petrogypsicor a duripan
f.A salic horizonicor natrichorizon

4. ❑Climate:HotAridandSemiaridorcoldregions,where
evapotranspirationfarexceedstherainfall.
❑Vegetation:Comprisesofxerophyticplants,likegrasses,
cacti,etc.
❑Relief:nearly-leveltoslightly-slopinglandscapes
❑ParentMaterial:unconsolidatedcolluvium,loessand
till.
❑Soilformingprocesses:calcificationandsalinization.
Formation:

5. Distribution
✓World:Sahara,GobiandTharDeserts,
NEandSWAfrica,centralAustralia,
south-westandextremenorthernUSA,
central(easttowest)Russia,Middle
EastcountriesandSouthAsia.
✓India:TharDesertofwestern
Rajasthan,NW India,including
Gujarat,Haryana,Punjab,aspocketsin
SpitiandLehareasoftheJammuand
Kashmir,easternKarnatakaandparts
ofAndhraPradesh.

6. ❑Undernormalaridclimaticenvironments,thesesoilsmaynotsupporta
singlecropinayear.
❑Thenon-gypsiferouslandscapes(inHaryana,PunjabandGujaratStatesin
India)areusedforgrowingonecrop(usuallyPearlmillet)inayearby
followingwaterconservationpracticesduringthesummermonsoon
periodandgrowingacroponstoredmoisture.
❑Thegypsiferoussoilsarebestleftforgrazingonly.
❑Thesesoilsalsosupportforraisingfruit,agro-forestryandplantation
cropswithoutanyconstraintofsalinization.
Land use:

7. ANDISOLS
❑AndisolswerefirstrecognisedinJapan
andweretermedasVolcanicashmaterial.
❑TheCentralconceptofAndisolsisthatof
soilsdevelopedfromvolcanicash.
Concept:

8. AndisolKey Identifying Features
❑Thesearetypicallydarkcoloured(withoutalbichorizon)
❑Lowbulkdensity(<0.9Mg/m
-3
)soilsmusthaveandic
properties(looseorfriable,darkcolouredmollicorumbric
surfacehorizonoverlyingabrowncambicB-horizon.
❑60percentormorevitricvolcanicashwithin60cmofthe
mineralsoilsurface.
❑Thesepropertiesresultfromthepresenceofsignificantamountof
allophoneoraluminium-humuscomplexesinsoils(originally
termed,amorphous).

9. ❑Climate:WarmandHumidclimate
❑Vegetation:DeciduousandDrydeciduous
Forest
❑Relief:Foundinalltopographicposition
❑ParentMaterial:Volcanicalluvium,
Volcanicloess.
Formation:

10. Distribution:
❖World:DominantlyobservedaroundtheRing
ofFireinthePacific,includingJapan,New
Zealand,Indonesia,Phillippines,'RiftValleyof
Africa,especiallyKenya,WesternCoastofUSA
andSouthAmerica.
❖India:Suchsoilsmaybeobservedinthe
IslandsofAndamanandNicobar,buthavenot
beenreportedsofar,althoughlocalizedvolcanic
activityhasbeenobservedthere.

11. Land use:
❑Itisadvantageoustogrowcropsthatgivelittleresponsetotheapplicationof
phosphorus,forinstance,sweetpotatoes(Ipomeabatata).
❑ThemajorlimitationintheuseofAndisolsistheirphosphorusfixingcapacity,
whichrendersPunavailableforplantgrowth.
❑Theyalsoposeproblemswhenusedforengineeringpurposes,becauseoftheir
fluffynature.
❑Andisolsaregenerallystableandresistwatererosionbecauseofhigh
infiltrationandpermeabilityrates,butwhendry,theyaresusceptibletowind
erosion.

12. GELISOLS
❑Permafrostobservedintheextremenorthernand
southernhemisphere.
❑Thesoilswithpermafrost(temperaturebelow0°C)
within1mofthesoilsurfaceorhavegelicsoil
materials(mineralororganic)thatshowevidenceof
cryoturbation(thatisfrostchurning).
❑Freezingandthawingplayanimportantroleinthe
developmentofthissoil.
Concept:

13. GelisolKey Identifying Features
1.Permafrost within 100 cm of the soil surface; or
2.Gelicmaterials within 100 cm of the soil surface and permafrost within 200
cm of the soil surface.

14. Formation:
➢Frostchurningormixing
➢Accumulationoforganicmatteroverthe
permafrost
➢Permafrostinfluencesthepedogenesisbyacting
asabarriertothedownwardmovementofthe
soilsolution.

15. ➢Thediagnostichorizons,including
Epipedons:mollic,umbricandhisticepipedons
Endopedons:argillicendopedon(SoilSurveyStaff,1999).

16. ➢World:NorthernUSA.Canada,Greenland,
Russia,Mongoliaandotherareasinthe
extremenorthernhemisphere.
➢India:Suchsoilshavenotbeenobservedor
reported.
Distribution:

17. Land use:
❖TheGelisolsarenotcultivatedbecauseofthelimitationofclimate.They
arelefttosupportnaturalvegetation.

18. References
➢SoilTaxonomy.ABasicSystemofSoilClassificationforMakingand
InterpretingSoilSurveys.SecondEdition,1999.BySoilSurveyStaff.
➢FundamentalsofSoilScienceBookbyIndianSocietyofSoilScience(ISSS)
➢ATextbookOfPedology:ConceptsandApplications(JSehgal)