Soil Science - Study Mode
[#406] CAN is mainly useful as which type of fertilizer application?
Correct Answer
(B) Top dressing
Explanation
Solution: CAN is calcium ammonium nitrate, also known as nitro-limestone or nitrochalk. It is a widely used inorganic fertilizer, accounting for 4% of all nitrogen fertilizers used. It is hygroscopic, and its dissolution in water is endothermic. It accounts for roughly 8% calcium and 21 - 27 % nitrogen. It is preferred for use on acidic soils. it is mainly useful as a Top dressing for fertilizer application.
[#407] Soil order characterized by excess of weathering with dominant iron and aluminium oxide clays, common in tropics is
Correct Answer
(D) Oxisols
Explanation
Solution: Soil order character is characterized by an excess of weathering with dominant iron and aluminium oxide clays, common in the tropics is Oxisols . Oxisols are a soil order in USDA soil taxonomy, best known for their occurrence in the tropical rainforest. The main processes of soil formation of oxisols are weathering, humification and pedoturbation due to animals. These are always red or yellowish colour, due to the high concentration of iron and aluminum oxides and hydroxide.
[#408] Total no. of electron consumed per unit N 2 fixation during BNF is
Correct Answer
(B) 8
Explanation
Solution: The total number of electrons consumed per unit of nitrogen fixation during Biological Nitrogen Fixation is 8. The overall reaction for the net formation of 2NH 3 from one N 2 is: N 2 + 8H + + 8e − + 16ATP + 16H 2 O ⟶ 2NH 3 + H 2 + 16ADP + 16Pi That shows nitrogen element takes 8 hydrogen ions and 8 electrons along with 16 molecules of ATP and water to produce 2 molecules of NH 3 .
[#409] Soft and unconsolidated calcium carbonate, usually mixed with varying amounts of clay or other impurities is described as
Correct Answer
(B) Marl
Explanation
Solution: Soft and unconsolidated calcium carbonate, usually mixed with varying amounts of clay or other impurities is described as Marl . Marl is an earthy material rich in carbonate minerals, clays, and silt. When hardened into rock, this becomes marlstone. Marl has been used as a soil conditioner and neutralizing agent for acid soil and in the manufacture of cement.
[#410] Mollisols are rich in which nutrient?
Correct Answer
(D) S
Explanation
Solution: Mollisols is a soil type that has deep, high organic matter, nutrient-enriched surface soil, typically between 60 - 80 cm in depth. This fertile surface horizon is called a mollic epipedon. Mollisols are rich in Sulphur nutrients and other mineral nutrients available are calcium, magnesium, potassium and sodium.