Soil Science - Study Mode

[#386] Which is the main constitution of Biogas?
Correct Answer

(A) Methane

Explanation

Solution: Biogas is a mixture of gases, like methane, carbon dioxide, hydrogen sulphide siloxanes, etc. but the main constituent of Biogas is Methane. It is produced from raw materials such as agricultural wastes, manure, municipal waste, plant material, sewage, green waste and food waste. It is a renewable source of energy.

[#387] Concentration of nitrogen in soil air is
Correct Answer

(C) 78%

Explanation

Solution: Our environment is the air around us. Earth’s atmosphere is made up of five main gases, nitrogen, oxygen, water vapour, argon and carbon dioxide. The concentration of nitrogen in soil air is 78%. And the other major component of air is 21% of oxygen.

[#388] Main difference between Soil profile and pedon
Correct Answer

(A) Profile is 2-D, pedon is 3-D

Explanation

Solution: The soil profile is the vertical section of the soil from the ground surface downwards to where the soil meets the underlying rock. Whereas a pedon is a sample of a body of soil that is 1 m 2 at the surface and extends to the bottom of the soil. A soil profile is smaller than a pedon. A soil profile is 2-D whereas a pedon is 3-D.

[#389] Which nitrogenous fertilizer industrially made first?
Correct Answer

(D) CaCN 2

Explanation

Solution: Calcium cyanamide (CaCN 2 ) is the nitrogenous fertilizer industrially made first. It is commercially known as Nitrolime . It was first synthesized in 1998 by Adolph Frank and Nikodem Caro. It is an inorganic compound with calcium salt of the cyanamide anion that is widely used as fertilizer. In contact with water, it decomposes and liberates ammonia.

[#390] Saline soils are managed by
Correct Answer

(D) Leaching of soluble salt

Explanation

Solution: Saline soils are managed by the leaching of soluble salt. It is done by the application of water in excess quantities than the need of plants and this method is termed as leaching requirement method. Managing the salinity involves striking a balance between the volume of water entering (recharge) and leaving (discharging) the groundwater system.