Soils of kerala and Soils of India in detail

Soil types of India and kerala

1. Module 3.Soil Health and Fertility Management Sub module:-Fundamentals of Soil SOILS OF KERALA AND SOILS OF INDIA

2. SOILS OF KERALA

3. Coastal alluvium These soils of marine origin are identified along the coastal plains and basin lands as a narrow strip . The elevation of the coastal area is generally below 5m MSL. The area has high water table and in some areas it reaches above the surface during rainy season. The soils of the coastal plains are very deep with sandy texture . The texture generally ranges from sand to loamy sand with grayish brown to reddish brown and yellowish red color . Sand content ranges from 80% and clay up to 15%. Even though these soils have high water table, the water holding capacity is poor due to the predominance of sand. Coconut is the major crop in the area. Cashew and other fruit trees are also grown

4. Mixed alluvium These soils are developed from fluvial sediments of marine, lacustrine and riverine sediments or its combinations. They occur below 20m MSL in the lowland plains, basins, valleys and along the banks of major rivers. These are mainly noticed close to coastal alluvium, Kuttanad and adjacent area and kole lands of Thrissur district. The soils are frequently flooded and submerged. The soils of depressions and broad valleys are subject to occasional flooding and s tagnation. The ground water table of these soils is generally high and it reaches above the surface during the rainy season. A wide variation in texture is noticed in these soils. Sandy c lay loam to c lay is the predominant texture. Sandy loam s oils are also met with. L ight gray to very dark brown is the common color of the soil. Paddy, other annual and seasonal crops like banana, tapioca and vegetables are grown here.

5. Acid saline soils Acid saline soils are present throughout the coastal area in patches with very little extent. Major area of this soil is identified in the coastal tract of E rnakulam , Thrissur and Kannur districts. The area under these soils comprises of low- lying marshes, waterlogged and ill drained areas near the rivers and streams, which are subject to tidal waves . Sea and backwater tides make these soils saline. During monsoon when rainwater and fresh water from rivers enter the fields, salinity is partially washed off. The area under these soils occurs mostly on plains a or below sea level. A wide variation in texture from sandy loam to clay is noticed with dark gray to black color . Paddy is the only crop that can be cultivated.

6. Laterite soils Laterite and lateritic soil are the weathering products of rock in which several courses of weathering and mineral transformations take place. This involves removal of bases and substantial loss of combined silica of primary minerals. In laterite and lateritic soils, over acidic rocks, induration and zonation are more pronounced . This induration is greater if the iron content is higher. These soils mainly occur in the midlands and part of lowlands at an elevation of 10 to 100m above MSL as a strip between the coastal belt and hilly midupland . The area comprises of mounds and low hills with gentle to steep slopes. Laterite soils are generally suitable for most of the dryland crops. It is mainly cultivated with coconut, arecanut, banana, tapioca, vegetables, yams, pepper, pineapple, fruit tree s etc. The % of gravel content in the soil and reduced soil depth limits the choice of crops. In laterite outcropped area with shallow soils, only cashew can be grown with vegetables.

7. Black cotton soils These soils are identified in alluvial plains, terraces and undulating plains of Chittur taluk in Palakkad district in patches. The elevation of the area ranges from 100 to 300m above MSL with gentle to moderate slope. These soils are developed on Khondalite suite of rocks traversed by lenticular bands of crystalline limestone and calc- granulites. These soils are very deep, black and calcareous. The texture of the soil ranges from clay loam to clay. They possess high shrink- swell capacity and hence exhibit the characteristic cracking during dry periods . A variety of crops such as coconut, sugarcane, cotton, chilly, pulses and vegetables are grown here.

8. Red soils These are found mostly in the southern parts of Thiruvananthapuram district and in pockets in catenary sequence along the foot slopes of laterite hills and mounds. These soils are identified in undulating plains of lowland with a general slope of 3 to 10% . These are mostly very deep and homogeneous in nature. The texture of the soil generally ranges from sandy clay loam to clay loam with red to dark red colour . Gravels are rarely noticed in these soils. A variety of crops such as coconut, arecanut, banana, yams, pineapple, vegetables, fruit trees etc., can be grown under proper management.

9. Hill soils The hill soils mostly occur above an elevation of 80m MSL. The area is hilly and has highly dissected denudational hills, elongated ridges, rocky cliffs and narrow valleys. The general slope range is above 10%. The texture of these soils generally range from loam to clay loam with average gravel content of 10 to 50%. In addition, stones and boulders are noticed in the subsoil. These soils have reddish brown to yellowish red/strong brown color. Generally, increase in clay content is noticed down the profile. The depth of the soil varies considerably from 60 to 200 cm depending on the lie of the land, erodibility of soil and past erosion. These soils are mostly friable and subject to heavy soil erosion. The area is suitable for all dryland crops like rubber, coconut, arecanut and fruit trees based on the topography. Crops such as banana, pepper, pineapple, vegetables can be grown in foot slopes.

10. Forest soils These soils are developed from crystalline rocks of archaean age under forest cover. They occur along the eastern part of the state, generally above an elevation of 300m above MSL. The area is hilly and mountainous with steep slopes , escarpments, elongated rocky summits and narrow 'V' shaped valleys. The depth of the soil varies considerably depending on erosion and vegetative cover. The soils are generally immature due to slow weathering process. Rock outcrops and stones are noticed on the surface. Gneissic boulders under different stages of weathering are noticed in the subsoil. The texture of the soil ranges from sandy clay loam to clay with reddish brown to very dark brown colour. Forest trees, shrubs and grasses are grown here

11. Kari soils Kari soils are seen in Alappuzha & Kottayam districts in marshy areas lying below Mean Sea Level. Kari soils have poor drainage, high acidity, salinity and decomposed organic matter at lower layers. The high amount of undecomposed organic matter and wood debris in the subsoil and intrusion of sea water into the area are the main source of extreme acid conditions. The soil texture ranges from sandy clay to clay with intermediate textures of silty clay loam and clay loam. Sand pockets are frequented in the solum . Soil Limitations - Impeded drainage, Toxic concentration of soluble salts, Extreme Acidity(pH<4 ), Presence of toxic compounds and elements, Low fertility

12. Management M easures - Limiting the generation of acidity by avoiding disturbance of the subsoil, Pre flooding to allow reduction of acidity possible before planting the crop, Double cropping of rice (or even shrimps as in our traditional Pokkali lands) which shortens the period of soil drying, Frequent flushing of the surface with good quality water and practicing Intensive shallow drainage, either by broad, shallow ditches between broad raised beds where flooding with good water will help in leaching of acidity and salts without deep drainage

13. Soils of India

14. Black soils It is dark grey to black in colour and ranges from fertile to poor. The soil is rich in clay (montmorillonite) particles and has neutral to slightly alkaline reaction. The soil is rich in bases, lime and calcium. The pH of black soil is 7.2 – 8.5. The soil is deficient in nitrogen , phosphate and organic matter but rich in potash , calcium and magnesium . It is soft when wet but forms hard blocks when dry and develops deep cracks. Black soil ranges from heavy clay (ill- drained) to loams (well-drained). Black soil is predominant in Maharashtra, Madhya Pradesh, western Andhra Pradesh, southern Tamil Nadu and northern Karnataka.

15. Red soils Such soil results from weathered material of metamorphic rocks . Kaolinite mineral is common. It is porous and friable neutral to acidic in reaction. Nitrogen, phosphate, lime and humus content are very low in this soil. It is found in parts of Tamil Nadu, Karnataka, north- east Andhra Pradesh, eastern parts of Madhya Pradesh, Bihar, West Bengal and Rajasthan.

16. Laterite soil Laterite soil is formed in areas receiving high rainfall with alternating wet and dry spells. This soil is red to reddish- yellow in colour. Heavy rains cause leaching of bases and silica from the surface of the soil. The soil shows acidic character with pH of 5 – 6 and is poor in nitrogen, phosphorus, potash, magnesium and lime. Such soil is porous and well- drained with poor water- holding capacity. The soil is found in eastern Andhra Pradesh, Karnataka, Kerala, Madhya Pradesh, Odisha, Assam and Ratnagiri district of Maharashtra.

17. Alluvial soils Alluvial soil is ideal for horticultural crops. Such soil is found along rivers. It consists of material deposited by rivers during flood. The soil is productive but may be deficient in nitrogen, phosphorus and humus. The soil greatly differs in colour, texture, drainage, presence or absence of sodium salts, etc. It is suitable for the cultivation of vegetables, flowers and fruits. The soil is found in all States of India along the rivers. The Indo- Gangetic soil is the best example of alluvial soil in India.

18. Desert soils Desert soil is sandy soil and is found in low rainfall areas. Such soil is alkaline in nature with high pH value and is unproductive . It is rich in soluble salts, and poor in nitrogen and organic matter content. The physical conditions of the soil are unfavourable as it has low water- holding capacity due to high sand content. Desert soil is found in parts of Rajasthan .

19. Forest and hilly soils These are shallow soils of elevation on the hills. higher and lower These are stony and infertile for the production of crops. These are low in bases and slightly acidic in reaction.

20. Saline and alkaline soils Saline soil shows white incrustation of salts (chlorides and sulphates of sodium, calcium and magnesium) on surface due to high evaporation during summers. It is also called ‘ white alkali soil’. Such soil is, generally, infertile and poor in drainage . Such soil is formed as a result of saline irrigation water and over- irrigation for a long time, which raises the water table of the soil. Alkaline soil is rich in carbonates and bicarbonates of sodium and is non- porous. It is also called ‘black alkali’ or ‘ Usar ’ soil. Uttar Pradesh, Punjab, Haryana, Rajasthan,Kerala , coastal Odisha and Sunderban region of West Bengal contain large patches of such soils.

21. Peaty and marshy soil This soil is highly acidic in nature and black in colour. Excessive wetness of the soil causes decay and degradation of dead vegetation, forming a layer of partially decomposed organic matter, resulting into peaty and marshy soil. Such type of soil is, generally, found in States like Tamil Nadu, parts of Bihar and Uttar Pradesh .

22. Types of Soils Chief characteristics Rich in suitable Crops Deficient Found in states of in Alluvial Mostly available soil in India (about 43%) which covers an area of 143mha (highest area in UP followed by Haryana, Delhi, Rajasthan). Formed mainly from Entisol soil order. Deposited in flood plains by transportation in streams and rivers. It is azonal soil with no horizons. Geographically, it is of 2 types: Khaddar/ newly formed alluvium, more sandy and Bhangar/ older alluvium, more clayey soils. Colour: Light Grey to Ash Grey . Texture: Sandy to silty loam or clay. Potash and Lime Rabi and kharif crops such as wheat, rice, sugarcane, cotton, jute etc. Nitrogen and Phosphoro us Occupy plains (from Punjab to Assam) and river valleys of Peninsular India. Punjab, Haryana, UP, Bihar, Jharkhand & West Bengal etc. Black (Regur soil) Second largest soil group with occupying 55mha (mainly in Maharashtra & MP). Formed mainly from Vertisol soil order. In Maharashtra, soil is derived from Deccan trap called as Regur or black cotton soil. Rich in montmorillonite clay (2:1) minerals. It is dark, fine grained soil with high clay content. It is called as late soil, as it moistened sufficiently in the later period of the season due to its lower permeability than other soils. Colour: Deep black to light black. Texture: Clayey. Lime, Iron, Magnesia and Alumina, Potash Cotton, sugarcane, jowar, tobacco, wheat, rice etc. Phosphoro us, Nitrogen and organic matter Deccan plateau- Maharashtra, Madhya Pradesh, Gujarat, Andhra Pradesh, Tamil Nadu, Valleys of Krishna and Godavari. Red Also known as Omnibus group of soil. 15mha (largest area in TN followed by Karnataka & Goa). Formed mainly from Alfisol soil order. Rich in kaolinite clay minerals. It is called as early soil because in the light & frequent rains of South west monsoon, red soils permit sowing being done earlier than other soils. Colour: Red because of Ferric oxide. The lower layer is reddish yellow or yellow. Texture: Sandy to clay and loamy. Iron, Manganese and Potash Wheat, rice, cotton, sugarcane and pulses Nitrogen, Phosphoro us and humus. Eastern and southern part of the Deccan plateau, Orissa, Chhattisgarh and southern parts of the middle Ganga plain.

23. Types of Soils Chief characteristics Rich in suitable Crops Deficient Found in states of in Latin word ‘Later’ which means Brick. Become so Organic soft when wet and so hard when dried. Laterite soils matter, Eastern & Western Ghats, has occupied about 25mha. Formed mainly from Laterite ultisol & oxisol soil order. Formed under heavy Iron oxide and Cashewnuts, tea, Nitrogen, Karnataka, Kerala, Tamilnadu, rainfall and high temperature. Maximum leaching potash coffee, rubber Phosphate Madhya Pradesh, Assam and and Orissa hills. takes place in this soil. Colour: Red colour due to iron Calcium oxide. Hills of Jammu and Kashmir, present in regions of high rainfall. Humus content is With fertilizers Tea Slopes of mountains in Forest and Mountain less and thus the soil is acidic. Iron plantation, fruits and Lime Uttarakhand, Assam hills and Medicinal plants West Bengal Generally unsuitable Deposited mainly by wind activities. High salt for cultivation but content. Lack of moisture and Humus. Kankar or Arid and Desert Impure Calcium carbonate content is high which Soluble salts, with irrigation, Humus, Western Rajasthan, north phosphate useful for wheat, Nitrogen Gujarat and southern Punjab restricts the infiltration of water. Texture: Sandy; barley, gram, bajra Colour: Red to Brown and melons Also called Usara soils. contain a larger proportion of sodium, potassium and magnesium, and thus, they Nitrogen Drier parts of Bihar, UP, Haryana, Saline and Alkaline are infertile, and do not support any vegetative Sodium, Potassium, Unfit for agriculture and Punjab, Rajasthan and growth. They have more salts, largely because of dry Magnesium Calcium Maharashtra climate and poor drainage. Occur in arid and semi- arid regions, and in waterlogged and swampy areas. Growth of vegetation is very less. A large quantity of Potash Kerala, Coastal region of Orissa Peaty and marshy dead organic matter/humus which makes the soil Iron and organic Useful for Jute and and & Tamil Nadu, and Sunderban alkaline. Heavy soil with black colour. mater Rice cultivation Phosphoro areas of West Bengal us

24. Soil tests Soil parameter Soil test Organic carbon Walkley and Black method Available nitrogen Kjeldahl’s method Available phosphorus C o lorimetry Available potassium Flame photometry pH Potentiometry Micronutrients Atomic absorption spectrophotometry

25. Soil health card

26. Soil test interpretations: pH

27. Soil test interpretations: EC

28. Soil test interpretations: Primary Nutrients

29. Soil test interpretations: Secondary Nutrients

30. Soil fertility classes

31. The only crop which can be cultivated in acid saline soils is a) Paddy b) Vegetables c) Millets d) Coconut

32. The only crop which can be cultivated in acid saline soils is a) Paddy b) Vegetables c) Millets d) Coconut

33. What is depth of soil sampling for agronomic crops a) 15cm b) 30 cm c) 15- 30 cm d) None of these

34. What is depth of soil sampling for agronomic crops a) 15cm b) 30 cm c) 15- 30 cm d) None of these

35. The number soil fertility classes in package of practices issued by KAU a) 9 b) 10 c) 11 D) 8

36. The number soil fertility classes in package of practices issued by KAU a) 9 b) 10 c) 11 D) 8

37. The Soil Health Card Scheme was introduced in the year A) 2015 B) 2016 C) 2019 D) 2020

38. The Soil Health Card Scheme was introduced in the year A) 2015 B) 2016 C) 2019 D) 2020

39. The most abundant soil type in Kerala a) Laterite soils b) Red soils c) Black cotton soils d) Acid saline soils

40. The most abundant soil type in Kerala a) Laterite soils b) Red soils c) Black cotton soils d) Acid saline soils

41. The most abundant soil type in India a) Laterite soils b) Red soils c) Black cotton soils d) A lluvial soils

42. The most abundant soil type in India a) Laterite soils b) Red soils c) Black cotton soils d) Alluvial soils

43. At what percentage of organic carbon is organic carbon considered low a) 0.5% b) 0.5- 1% c) > 1.5% d) None of these

44. At what percentage of organic carbon is organic carbon considered low a) 0.5% b) 0.5- 1% c) > 1.5% d) None of these

45. What is the quantity of soil sample to be given to the laboratory for soil testing a) 500 g b) 1 kg c) 0.5 kg d) Both a and c

46. What is the quantity of soil sample to be given to the laboratory for soil testing a) 500 g b) 1 kg c) 0.5 kg d) Both a and c

47. Which of the following soil have alkaline pH a) Desert soils b) Black cotton soils c) Both a and b d) None of these

48. Which of the following soil have alkaline pH a) Desert soils b) Black cotton soils c) Both a and b d) None of these

49. Dominant mineral in red soil a) Vermiculite b) Kaolinite c) Montmorillonite d) Illite

50. Dominant mineral in red soil a) Vermiculite b) Kaolinite c) Montmorillonite d) Illite