Soil Science - Study Mode
[#181] Which one of the following minerals is the main source of boron in soils?
Correct Answer
(B) Tourlamine
Explanation
Solution: Tourlamine is the one mineral among the given options that is the main source of boron in soils. Tourmaline is a crystalline silicate mineral group in which boron is compounded with elements such as aluminium, iron, magnesium, sodium, lithium or potassium. It occurs as long, slender to thick prismatic and columnar crystals that are usually triangular in cross-section.
[#182] Example of Gum Producing Bacteria is
Correct Answer
(D) All of the above
Explanation
Solution: Azotobacter, Beijerinickia and Rhizobium all the given options are an example of Gum producing Bacteria. The gums produced by bacteria are polysaccharides, high molecular weight polymers that are produced by the cell-wall anchored enzymes of microorganisms. The gums are composed of sugar residues linked by glycosidic linkages and may be linear or highly branched.
[#183] Bone meal contains . . . . . . . . % of P 2 O 5 .
Correct Answer
(B) 20%
Explanation
Solution: Bone meal is a mixture of finely and coarsely ground animal bones and slaughterhouse waste products. It is used as a dietary supplement to supply calcium and phosphorus to monogastric livestock in the form of hydroxyapatite. It is slow release organic fertilizer, it supplies phosphorus, Calcium and a small amount to plants. Bone meal contains 20% of P 2 O 5 .
[#184] Equivalent acidity of anhydrous ammonia is
Correct Answer
(A) 148
Explanation
Solution: Equivalent acidity is defined as the acidity developed by a fertilizer when applied to soils, measured in terms of calcium carbonate required for its neutralization. It can be calculated as the calcium carbonate required to neutralize the acid residues caused by acidic fertilizers in the soil. The equivalent acidity of anhydrous ammonia is 148. It is the highest among all the fertilizers.
[#185] Chernozem soils are found in
Correct Answer
(A) Russia
Explanation
Solution: Chernozems are humus-rich fertile black grassland soils used extensively for growing cereals or for raising livestock. It has a lighter lime-rich layer beneath, typically occurring in the temperate occurring in the temperate grasslands of Russian steppes. Thus it is mainly found in Russia . Wheat, barley and maize are typically the principal crops grown, alongside other food crops and vegetables.