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SOILS OF SRI LANKA

SOILS OF SRI LANKA. ALLUVIAL SOIL.

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SOILS OF SRI LANKA

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  1. SOILS OF SRI LANKA

  2. ALLUVIAL SOIL Major characteristics of Alluvial Soils are:-  1)These are of Transported origin. 2)Alluvial soil as a whole is very fertile. 3)According to their age, these soils have been classified into 2 types:- ~Old Alluvium or Bhangar Soil ~New Alluvium or Khaddar Soil 4)These soils contain adequate proportion of Potash, Lime and Phosphoric acid.5)  Silk, clay, gravel and sand the main constituents of alluvial soil.6)They are ideal for the growth of crops like sugarcane, pawatta,corn,rice,etc7)It is commonly found in riverbed and flood plains.By-AnanyaSmirti

  3. REDDISH BROWN LATOSOL SOIL Reddish brown latosol soils are the next prominent soil group found in the wet zone of Sri Lanka. Most of these soils occur on terrains that have been incised by ecological erosion. These soils are relatively young. The texture is mostly sandy clay loam and the structure is strong crumb to granular under natural vegetation. These soils are normally deep, soil reaction is slightly acidic and the cation exchange capacity may vary from 4-15 c mol kg-1 in surface soils.

  4. REGOSOLSOILS Characteristics: 1 .) Organic matter content is low 2 .) Narrow coastal regions of Sri Lanka & in slopes of mountains 3 .) Cationexchange capacity is high 4 .) Nitrogen & phosphoros content is low and so fertilizers are to be given many times in small quantities. 5 .) Calcium & magnesium are present in good quantities. 6 .) It is neutral in nature. 7 .) It has underground water layer capacity 8 .) Because of rich water drainage capacity ,irrigation is a problem. 9 .) Coconut & cashew are mainly grown. The yellow color in the map shows regosol soil By Krittika , Ankita, Antara , Mohona & Dolly

  5. PHYSICAL CHARECTERISTICS,AREAS & CROP GROWN IN RED-YELLOW PODZOLIC SOILS OF SRILANKA 1. Physical Characteristics of Red-Yellow Podzolic soils: The physical properties of Red Yellow Podzolic are favourable for wide-ranging agricultural purposes. The fertility of wet zone soils is poor because these soils have been extensively leached due to high rainfall. The CEC values of most of the soils are low. Therefore, special fertilizer management practices on these soils are required. The base saturation of the dry zone soils remains at a higher range. 2. Area of Red-Yellow Podzolic soils in Srilanka 1525906 hactors. 3. Crops Grown: Rice. PPT BY: TRIPARNA, EKTA, DEBARATI

  6. LATOSOL SOIL Latosol is a name given to soils found under tropical rainforest s with a relatively high content of iron and aluminium oxides. Crops grown:- Potato, onion, tobacco

  7. GRUMOSOL SOIL Characteristics:- Horizon A of grumusol soil is black in colour Contains enough amount ofCalcium and Magnesium Cation exchange is about 65-90 Water drainage is ill due to high clay content It is very difficult to use for cultivations because soil stick in wet condition and hardens under dry condition Too hard to machinaries Distribution Seen in :- Southern parts of Jaffna district Thunukaya area Murukan area Mannar district Cultivating crops:- Suitable for paddy cultivation Vegetables and cereals can be cultivated by means of irrgation.

  8. BOG AND HALF BOG SOILS CHARACTERISTICS OF BOG AND HALF-BOG SOILS:- THE COLOUR OF THESE SOILS RANGE FROM ASH BROWN TO BLACK. BOG AND HALF BOG SOIL HAVE A VERY HIGH CATION EXCHANGE CAPACITY THAT IS 100-200 .IT CONTAINS HIGHEST AMOUNT OF ORGANIC MATERIALS DRAINAGE IS POOR. SOIL IS BEINGCOVERED BY WATER. ACIDITY IS HIGH ,ie: PH VALUE IS BETWEEN 4.0-5.0. H2S(HYDROGEN SULPHIDE) CAN BE POISONOUS AS SOIL IS BEING UNDER FLOOD. IT IS FOUND IN THE VALLEYS OF WET ZONE,NEAR RIVER BASINS AND COLOMBO,KALUTHARA,GALLE AND MATHARA .GREENS CAN BE CULTIVATED ON A RAISED BEDS IN BOG AND HALF BOG SOIL.CULTIVATION OF VEGETABLES ALSO CAN BE FORMED IF DRAINAGE IS POSSIBLE. UNDER FLOOD CULTIVATION SEDGES CAN BE CULTIVATED.

  9. IMMATURE BROWN LAOMY SOIL Characteristics:- Immature brown loamy soil is a juvenile soil; in the soil profile thickness of the first horizon is about 15cm -25cm colour is varied from dark brown to dark ash brown special feature of the soil is that flake graphite has spread out all over the soil profile. The thickness of second horizon is about 60cm. Third horizon contain flake graphite. This soil contain low amount of organic material and nitrogen. It is slightly acidic soil. Cation exchange capacity is 10 to 20 and base saturation is in between 50 to 70. Immature brown loamy soil is found in districts of wet zone such as Kegalle,Kandy,Kurungala and on the slope of hills in the dry zone. Immature brown loamy soil is found in districts of wet zone such as Kegalle,Kandy,Kurungala and on the slope of hills in the dry zone. Plants with short root system such as grass, vegetables and yam can be cultivated because depth of soils is less. Tea, Rubber, Coconut, Pepper and areca nut are suitable if soil is deep.

  10. LATOSOLIC SOIL OF SRILANKA Characteristics-The colour of its subsoil is red or yellow brown.It contains less amount of organic materials,nitrogen,phosphorous,pottasium & magnesium.it is slightly acidic.It is highly erosive in nature &retension of moisture is low. Area-It stretches from north to Puttalain through Mannai by one side and again from middle of north to Mullative by other side. Crops grown-Plants like chilly,onion,peanut,tobacco cashew,orange can be cultivated here.

  11. Reddish Brown Earth Soil CROPS GROWN Crops such as paddy, maize, green gram, cowpea, chilli, vegetables, onions, tea, rubber and coconut can be cultivated on reddish brown earth soil. CHARACTERISTICS These soils are reddish to reddish brown in colour and found in the upper and mid slopes of the landscape in the dry zone. The normal depth is about 1.0-1.2 m. and the water holding capacity ranges from 100-140 mm/meter depth of soil. The steady infiltration rate ranges from 1-5 cm/hr. The percolation rates of the wet puddled soils for the first time exceeds 100 mm/d and remains at a higher value of 10-20 mm/d even after 6 years of continuous puddling. AREA Area of reddish brown soil in Sri Lanka are – vanuiya, trincomalee, anuradhapuraya, polonnaruwa, ampara, monaragala, hambantota.

  12. REDDISH BROWN LATOSOLIC SOIL • Thickness of the horizon A of Reddish brown latooolic soil is about 30 meters. It is very thin in cultivated fields. • This soil has moderate fine texture. Organic materials and nitrogen are little bit of low. • It contains potassium, calcium and magnesium moderately. Phosphorus content is less. • Better cation exchange capacity. It is 12-20. • Depth, texture and water drainage maintain is at a better level. • Base saturation is 20-30. • Soil is slightly acidic. • The soil has distributed in districts such as Kandy, Mathale, Kurunagala, Nuwara-Eliya and Kegalle. • Tea, rubber, cocoa, pepper, coffee, clove, cardamom, fruits and vegetables can be cultivated successfully in the reddish brown latosolic soil.

  13. CALCAREOUS SEDIMENTS OF SRILANKA The term calcareous can be applied to a sediment, sedimentary rock, or soil type which is formed from, or contains a high proportion of, calcium carbonate in the form of calcite or aragonite. Marine sediments Calcareous sediments are usually depositedshallow water near land, since the carbonate is precipitated by marine organisms that need land-derived nutrients. Genera lly speaking, the farther from land sediments fall, the less calcareous they are. Some areas can have interbedded calcareous sediments due to storms, or changes in ocean currents. Calcareous ooze is a form of calcium carbonate derived from planktonic organisms that accumulates on the sea floor. This can only occur if the ocean is shallower than the carbonate compensation depth (CCD). Below this depth, calcium carbonate begins to dissolve in the ocean, and only non-calcareous sediments are stable, such as siliceous ooze or red clay. Calcareous soils Calcareous soils are relatively alkaline, in other words they have a high pH. This is because of the very weak acidity of carbonic acid. Note that this is not the only reason for a high soil pH. They are characterized by the presence of calcium carbonate in the parent material and may have a Calcic horizon, a layer of secondary accumulation of carbonates (usually Ca or Mg) in excess of 15% calcium carbonate equivalent and at least 5% more carbonate than an underlying layer.[2] Calcareous mine

  14. DESERT SOIL Characteristics • Contains soluble salts. • 90% sand & 5% clay. • Rich in Nitrates & Phosphates. • Friable, sandy & low moist content. Areas • Arid & semi arid regoins of Rajasthan, Haryana, Punjab & Gujarat. Crops grown • Barley • Millet

  15. NON-CALCIC BROWN SOIL IN SRI LANKA Characteristics: Color range from dark brown to ash brown. Mostly Non-calcic brown soil contains sand. Horizon B has more than 40% of base saturation and a high amount of clay than horizon A. This soil can be found in dry zone. Nitrogen in the top layer of this soil is decomposed. This is a slightly acidic soil and has much of Calcium and Magnesium. Cation exchange capacity is 5-11. Structure is breakable. Distribution: Non-calcic brown soil is distributed in Ampara, Baticalloa, some areas of Galoya Valley and area in around Mahawa in Sri Lanka. Cultivating crops: Crops like Cereals, green gram, Cowpea, Peanut, Sugar canes, Chilli, vegetables and onions can be cultivated in non-calcic brown soil by applying correct conservation techniques and better irrigation.

  16. Solodized Solonetz soil Median values of pH, conductivity, organic and inorganic carbon, and mechanical analyses are reported for nine solodized solonetz soils and eight solonetz-like soils. A regional Dark Brown prismatic profile is included for comparison. These data show that for solodized solonetz soils the A horizons are moderately acid, with the A2 and A3horizons showing the greatest acidity. The B1 is neutral, and the lower B and C horizons are alkaline in reaction. The solonetz-like profiles show a similar trend, but pH values are higher in the A horizons. Conductivity rises progressively from the A1 horizon downward in the solodized solonetz group, whereas in the solonetz-like group the conductivity remains very low throughout.

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