Soil Science - Study Mode

[#666] Which of the following nutrient elements is not a micronutrient?
Correct Answer

(C) S

Explanation

Solution: Among the following given options, Sulphur is not a micronutrient , whereas copper, zinc and Iron are micronutrients, required in very small amounts by plants for their functioning and growth. Sulphur is a macronutrient, required in large proportions by plants for adequate growth and development. It is used in the formation of amino acids, proteins, and oils. It is also necessary for chlorophyll formation, promotes nodulation in legumes and helps activate specific enzymes and vitamins.

[#667] The neutralising values of the following liming materials are such that
Correct Answer

(B) CaO > Ca(OH) 2 > CaMg(CO 3 ) 2 > CaCO 3

Explanation

Solution: The neutralizing value is the percentage of the material that can neutralize acid expressed as the calcium carbonate equivalence (CCE) of the product. The neutralizing values of the following liming materials are such that: CaO > Ca(OH) 2 > CaMg(CO 3 ) 2 > CaCO 3 Calcium oxide has the highest value i.e. 178.5, followed by 135 of calcium hydroxide, then 108.5 of calcium magnesium carbonate and lastly 100 of calcium carbonate.

[#668] The term catena (a Latin word means a chain) was introduced by
Correct Answer

(A) Milne (1935)

Explanation

Solution: The term Catena was introduced by Geoffrey Milne in 1935. This term describes the soil topography units and the lateral variation in soils over a hillslope. The concept of a catena was developed to analyze the regular variation of soils across a slope. A mature catena is in equilibrium as the processes of deposition and erosion are in balance.

[#669] Nutrient Use Efficiency of Micro Nutrients is
Correct Answer

(C) 2 - 5%

Explanation

Solution: Nutrient use efficiency (NUE) shows the ability of crops to take up and utilize nutrients for maximum yields. It involves three major processes in plants: uptake, assimilation, and utilization of nutrients.
Nutrient Use Efficiency of Micronutrients is 2% - 5%. The seven micronutrient elements are boron, zinc, iron, copper, molybdenum, manganese and chlorine.

[#670] Gapon's equation is widely-used equation to describe
Correct Answer

(B) CEC of soils

Explanation

Solution: Gapon’s equation is a widely used equation to describe the CEC of soils. CEC is the cation exchange capacity of the soil and it is a measure of how many cations can be retained on the soil particle surface. The Gapon exchange equation is commonly used to study binary heterovalent exchange reactions. The Gapon equation help to maintain the ratio of sodium to calcium on the soil colloid surface content.