Soil Science - Study Mode

[#661] Which group of microorganisms have highest biomass in soil
Correct Answer

(C) Fungi

Explanation

Solution: Fungi is the group of microorganisms that have the highest biomass in the soil. The maximum limit is up to 790 μg C/g soil and it is found in the soil with surface organic horizons in the form of thin moss/lichen litters, in which the development of fungal mycelium is most active.

[#662] In soil Taxonomy udolls is a suborder of
Correct Answer

(B) Mollisols

Explanation

Solution: Udolls is the suborder of Mollisols in soil taxonomy. They are divided into eight suborders: Albolls, Aquolls, Rendolls, Gelolls, Cryolls, Xerolls, Ustolls and Udolls. Mollisols are the soils of grassland ecosystems or cropland. They are characterized by a thick, dark surface horizon. Mollisols are among some of the most important and productive soils in the world.

[#663] The least hygroscopic fertiliser is
Correct Answer

(C) SSP

Explanation

Solution: SSP is the most popular phosphatic fertilizer after DAP as it contains 3 major plant nutrients i.e. Phosphorus, Sulphur and Calcium along with traces of other micronutrients. SSP is a grey to brownish coloured material containing monocalcium phosphate and calcium in almost equal proportions. It is the least hygroscopic but needs moisture-proof packing to avoid lump formation during storage.

[#664] Honey-comb structure is found in which group
Correct Answer

(A) Phyllosiliocate

Explanation

Solution: The honeycomb structure is found in Phyllosilicate , also termed sheet silicates. The basic structure of the phyllosilicates is based on interconnected six-member rings of SiO 4 -4 tetrahedra that extend outward in infinite sheets. Three out of the 4 oxygens from each tetrahedral are shared with other tetrahedra.

[#665] Tourmaline is the best source of
Correct Answer

(C) B

Explanation

Solution: Tourmaline 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 aluminum, iron, magnesium, sodium, lithium or potassium. It occurs as long, slender to thick prismatic and columnar crystals that are usually triangular in cross-section.