Concept of Lateritic soils and how it proves to be unsuitable for agriculture production with some management approaches.

1. Constraints of Lateritic Soils
in Crop Production
Gaurav Jha
L-2014-A-132-M
Soils 511

2. Lateritic Soils
• In Subtropical and Tropical regions between 25
degrees North and South latitudes.
• Deposits are thick upto 20m.
• Highly ferruginous
• Vesicular
• Unstratified deposits
• Highly weathered
• Qualify for Ultisols and Alfisols
with Kandic properties
• Crops for higher topography:
1. Cocoa
2. Cashew
3. Tea
4. Coffee
5. Rubber
• Crops for lower topography:
1. Rice
2. Banana
3. Coconut
4. Arecanut

3. Formation and distribution of
lateritic soils
Kerala, Tamil nadu, Orissa, Andhra
Pradesh, West Bengal, Karnataka

4. Profile of
Lateritic Soils
Santiniketan, Birbhum (W.B.)

5. Constraints of lateritic soils
Physical constraints Chemical constraints
 Soil erosion and hardening of
laterites
 Low water holding capacity
 Reduced soil volume due to
concretions and occurrence of
plinthite and petroplinthite
 Drought stress
 Low CEC
 Low organic matter
 High acidity
 Fe and Al toxicity
 High Phosphorus fixation
 Poor nutrient status

6. Physical Constraints

7. I. Soil erosion and hardening of laterites
Views of
Gullies at the
west of
Bhatina
village,
Rampurhat
 Laterites are very much erosion prone soil in India because---
I. It has high erodible kaolinitic clay (B horizon)
II. Surface crusting of iron oxides
III. Light textured
IV. Low moisture retention capacity and
V. Less vegetative growth

8. IRS 1D LISS III FCC image (2001) of the Rampurhat block of Birbhum district
in West Bengal(greenishblue patches are gully prone lateritic land).
Ghosh et al (2011)

9. II. Low water holding capacity
Soil Depth(in cm) Available water(%) Infiltration Rate
Lateritic 0-15 3.5 10.8
15-30 4.6
30-60 6.3
Black 0-15 15.3 0.60
15-30 10.2
30-60 13.4
Ushakumari (1986)
 Drying out and hardening of upper horizons
 Forms impenetrable crust
 This reduces the ability of soils to absorb water
 Irreversible hardening

10. III. Reduced soil volume due to concretions and
occurrence of plinthite and petroplinthite
 Plinthite is a redoximorphic feature in highly weathered soil
 Product of pedogenesis, it commonly occurs as dark
red redox concretions
 Changes irreversibly to an ironstone hardpan or to irregular soil
aggregates on exposure to repeated wetting and drying
 Structure change from angular blocky to massive structure

11. Chemical Constraints

12. I. Low Cation Exchange Capacity
Due to lack of organic matter
Hydrous nature of clay
Percent base saturation ranges from 80 to 95 %
which reflects the dominance of basic cations in the
exchange complex
Exchangeable Aluminium is the predominant cation.
Low activity clay, therefore CEC is contributed by
pH-dependent charges

13. II. High Soil Acidity
 Measure of soil acidity in lateritic soils-
1. Exchangeable Hydrogen ion
2. Exchangeable Aluminium ion
3. Effective Cation Exchange Capacity
 High acidity attributed to acidic parent material
 Three strategies to attenuate soil acidity-
1. Liming to reduce Al-saturation below toxic levels
2. Liming to promote Ca and Mg in soil
3. Use of plant species tolerant to Al, Fe, Mn toxicities
Sehgal et al (2000)

14. Kisiniyio et al (2014)
Effect of lime on exchangeable Al3+ during the cropping period
on a western Kenya acid soil

15. III. High Phosphorus Fixation
 High P-fixation is attributable to
1. Hydrous oxides of iron and aluminium
2. Dominance of 1:1 type of clay
3. Increased soil weathering and decreased soluble silica
4. Acidic soils have higher P-fixing capacity
5. Fe and Al phosphates are formed and adsorption reaction occurs

16. IV. Poor nutrient status
 Fe and Al ions occupy negatively charged sites useful to store
nutrients
 Extremely weathered laterites are devoid of primary minerals,
bases and silica
1.) Pronounced leaching
2.) Relative accumulation of sesquioxides
 Deficiency of P, K, Ca, Mg, Zn, B
 Toxicity of Al and Mn
 Low soil fertility status

17. Potentials of
lateritic soils
Western Ghats-Mango cultivation

18. Case Studies on
lateritic soils

19. Bio-reclamation –Converting degraded lateritic soils into productive
land in Niger by ICRISAT
Trees intercropped with vegetables under BDL system by ICRISAT, Nigeria
Degraded lateritic soil of Nigeria
Strategy-Bio-reclamation of Degraded Lands
(BDL) system which enhanced the conversion of
degraded crusted soils into productive lands in
Niger by ICRISAT
How it was achieved- By combining indigenous
water harvesting technologies (micro-
catchments, planting pits and trenches),
application of animal and plant residues and
plantation of high-value fruit trees and annual
indigenous vegetables that are resilient to
drought environments
Tree species- Ziziphus mauritiana (Pommedu Sahel),
sweet tamarind (Tamarindus indica), the domesticated
Sclerocaria birrea (marula) and the domesticated
Acacia senegal
Leafy vegetables-(Cassia tora, Gynandropsis
gynandra, Corchorus stridens, Cerathotheca
sesamoides, Leptadenia hastate, Hibiscus sabdariffa
and wild Amaranthus).
CASESTUDY-1

20. Advantage of vermicomposted FA over FYM in
augmenting growth and yield of the crop.
Vermicomposted FA + NPK100 (A), FYM +
NPK100 (B) and yield of potato from these
treatments (C).
Location-Birbhum, West Bengal
Chattopadhyay et al (2012)
CASESTUDY-2

21. Conclusions
 Laterites are formed as a result of continuous wetting and drying for
years and includes alfisols, oxisols and ultisols which are highly
weathered soils.
 Lateritic soils are highly weathered soils devoid of major nutrients like P,
Ca, Mg, K, Zn, B etc. Howevever toxicity of Fe and Al may be observed
as they are acidic soils.
 Liming in tropical areas are not as effective as in temperate regions due
to low activity clays.
 Formation of plinthite layer hinders the root penetration for germinating
crops. However, rice can be grown as it needs hard pan formation during
its growth period.
 Vermicomposting and use of fly ash are promising practices to increase
the nutrient use and its efficiency.