Soil Science - Study Mode

[#846] Under electron Microscope, shape of kaolinite is
Correct Answer

(A) Hexagonal

Explanation

Solution: Kaolinite is a clay mineral of the chemical formula Al 2 O 3 2SiO 2 ยท 2H 2 O that has a structure of a 1 : 1 uncharged dioctahedral layer where each layer consists of a single silica tetrahedral sheet and single alumina octahedral sheet. Under an electron microscope, the shape of Kaolinite is Hexagonal (book-like) and non-idiomorphic crystal forms are associated with rhombohedral blocky alunite.

[#847] For the first time who isolated bacteria from root nodule?
Correct Answer

(B) Beijerinck

Explanation

Solution: Beijernick , a Dutch microbiologist and botanist was the one who isolated bacteria from root nodules for the first time. He discovered new types of bacteria from soil and described biological nitrogen fixation. He was the first to recognize that viruses are reproducing entities that are different from other organisms.

[#848] Indian agriculture is operating at a negative balance of plant nutrients
Correct Answer

(D) 8 - 10 mt

Explanation

Solution: Indian agriculture is operating at a negative balance of plant nutrients 8 - 10 mt. The nutrient balance is defined as the difference between the nutrient inputs entering a farming system (mainly livestock manure and fertilizers) and the nutrient outputs leaving the system (the uptake of nutrients for crop and pasture production). Nutrient balances provide information about environmental pressures. A nutrient deficit (negative value) indicates declining soil fertility.

[#849] According to USDA land Capability Classification, land are classified under . . . . . . . . broad groups.
Correct Answer

(A) 2

Explanation

Solution: According to USDA land capability classification, the land is classified under 2 broad groups that are (i) Arable land (cultivable) and (ii) non-arable land (Noncultivable). Land Capability Classification (LCC) is an exercise for interpretative, grouping, and grading soils according to their potentialities and limitations. It helps to organize significant soil factors for conservation.

[#850] Mineralisation releases nutrients in soils are tied up in
Correct Answer

(C) Organic matter

Explanation

Solution: Mineralization releases nutrients in soils that are tied up in Organic matter . Mineralization is the conversion of a nutrient from the organic (i.e. bound to carbon and hydrogen) form to the inorganic form. The process occurs when organic materials, such as soil organic matter, manure, plant residue, or biosolids, are decomposed by soil microorganisms. Mineralization is the main organic matter conversion process, which leads not only to the preservation of organic matter in the soil but also to its sequestration.