Major important Soils in India and Tamil Nadu.pptx

Major types of soils in India and Tamil Nadu

1. Unit I Introduction to Agriculture Dr. S. Marimuthu ., Ph.D . Asst. Professor (AGR) Major soils of India and Tamil Nadu

2. Soil - Habitat for Plants Latin “SOLUM” - “ FLOOR or GROUND” Natural body composed of mineral & organic constituents , having a definite genesis and a distinct nature of its own: “ Dokuchaiev (1900)” “ S oul O f I nfinite L ife” - J.S. Kanwar

3. Major soils of India Eight - Indian Council of Agricultural Research (ICAR) Genetic System Classification USA Soil Taxonomy 1. Alluvial soils : Inceptisols (H) , Entisols , Alfisols , Aridisols 2. Black soils : Verrtisols , Inceptisols , Entisols 3. Red soils : Alfisols , Inceptisols , Entisols 4. Laterite and Lateritic soils : Oxisols (L), Ultisols , Inceptisols 5. Saline and Alkai soils : Aridisols , Inceptisols , Alfisols , Entisols , Vertisols 6. Desert soils : Aridisols, Entisols 7. Forest soils and Hill soil : Inceptisols , Alfisols , Mollisols , Ultisols 8. Peaty and Marshy soils : Histosols , Inceptisols , Entisols

4. Alluvial soil or Indo-Gangetic Alluvium Predominant soil - 48 m.ha - India Deltaic, calcareous & coastal alluvium Formed-transportation in streams & rivers - deposited in flood plains or coastal belts New soil - no distinct soil horizons than older High altitude - acidic & plains - neutral to alkaline ( medium P & high K)

5. Kankar nodules – CaCo 3 Newer alluvium - “Khadar” Sandy, light colour & less Kankar nodules Older alluvium - “ Bhangar ” High clay, dark colour & more Kankar nodules

6. Alluvium - Area and crops Indus, Ganges, Brahmaputra, Godavari, Krishna, Cauvery & Tambiraparani deltas Rich in nutrients (fertile) - good crop growth – more water Rice, wheat, cotton, maize, sugarcane, vegetables, jute, oil seeds, millets, pulses & fruits

7. Black soil – “ Titaniferous magnetite” Dark-grey - (clay humus) - 32 m.ha Montmorillonite – clay ( 30-40%) – WHC high Swelling (during wet) & shrinkage ( dry) – Fe, lime, Ca , Mg, Al, CO 3 - Deep cracks > 30-45 cm. Kovilpatti (2 to 3 m - width of 1 to 6 cm) Suited after secondary tillage

8. “ Black cotton soil” High CO 3 - of Ca & Mg, CEC (40-60 m.e. /100 g) Low N, Medium P & Medium to high in K (Indian soil) – rainfed areas Cotton, bengal gram, mustard, millets, pulses, oil seeds (sunflower, safflower) MH, MP, South Orissa, South and Coastal AP, North KA and parts of TN

9. Red soil – Fe 2 O 3 - Hematite Formed from granites & metamorphic rocks – rich in Fe & low OM ( 30 m.ha ) Semi-arid areas (red to yellow – Limonite) Drained with moderate permeability Low CEC & WHC, high acidic, low clay & high sand than Vertisol Time dark brown to dark – valley/plain GJ, TN, KA, AP, North & East of AP, MP, Parts of Bihar and UP Millets, pulses, oil seeds ( Ground nut , gingelly , castor) and cassava

10. Laterites & Lateritic soil Process of “ laterisation ” (leaching of all cations leaving Fe and Al oxides) Modified form of red soil – low clay and High organic matter (fertility) and medium WHC Very hard - no water & Cohesive high Hills and foothill areas Acid loving crops (Plantation crops) and fruits (pineapple, avacado ), Tea, rubber, pepper, spices & lower elevation (rice)

11. Laterites and Lateritic soil Tropical and sub tropical - alternate wet and dry season. Rich Sesquoxides (Fe 2 O 3 /Al) , primary silicate minerals. Hard - drying after wetting and turn hard brick - ( Hydrated oxides of Al and Fe + Mno , titania ) No alternate wetting – rich in Iron Laterites at high topographic position to lower levels by streams - Low activity clay Hilltops and platean of Orissa, MH, KL, TN North Eastern, AP, Kar , Assam.

12. Arid & Desert soil Mechanical disintegration - wind deposit Less vegetation - Xerophytic palnts - Hot & Cold Temp . - S and dunes - clay (<8%) Low fertility, WHC, more soil erosion, less N & Humus Sodic salts (high Na) leads to alkalinity Rajasthan ( Thar desert), Haryana & Punjab Date palm, cucumber, millets (Saudi Arabia, UAE, Jordan, Sudan etc

13. Forest and Hill Soils Forest - 75 m ha (18% ) Profile developed by variation in climate & altitude, plant species etc. Brown forest, podzolic (Himalayas), Red & Lateritic ( Deccan Plateau)

14. Mountain soil Hill slopes & Rich humus Formed by deposition of OM from forest Poor Potash and Lime Assam, Kashmir, Sikkim & AR Tea, Coffee, Spices & Tropical Fruits

15. Peat and Marshy soil Deposition of organic matter by the elevated soil Kerala, coastal regions of WB, Orissa, South and East coast of TN Not suitable for majority of crops Rice (coastal rainy area)

16. Comparison of three types of soils Parameters Saline soil Saline alkali Alkali soil EC ( dS /m) >4 >4 <4 ESP (%) <15 >15 >15 pH <8.5 <8.5 >8.5 Solanchaks (Saline), Solenetz ( Sodic ) – Ardisols , Incep . Alfis , Vertisols

17. Soils of Tamil Nadu Red loam (79.8 L. ha & 61.7%) Parts of Kancheepuram , Cuddalore , , Dharmapuri , , Tiruchirappalli, Thanjavur , Ramanathapuram , , Tirunelveli, Sivagangai , Thoothukudi , Virudhunagar , Dindigul and The Nilgiris Laterite soil (3.8 L.ha & 2.9%) Parts of The Nilgiris Black soil (15.0 L. ha & 11.6%) Parts of Kancheepuram , Cuddalore , , Thiruvannamalai , , Dharmapuri , , Ramanathapuram , Tirunelveli, Sivagangai , Thoothukudi , The Nilgiris , Virudhunagar and Dindigul coastal alluvium (9.8 L. ha & 7.6%) Coasts in the districts of Ramanathapuram , Thanjavur , Nagapattinam , Cuddalore , Kancheepuram and Kanyakumari River alluvium (21.0 L. ha & 16.2%) All river deltaic areas (Cauvery, Vaigai , Tambiraparani )

18. Thanks a lot