Soil Science - Study Mode

[#256] Puddled soil comes under which grade of soil structure?
Correct Answer

(B) Massive

Explanation

Solution: Puddled soil is the soil in which the structure has been destroyed by the physical impact of raindrops, tillage when wet, or trampling by animals. Puddled soil comes under the massive grade of soil structure. Puddling of some heavy–textured soils leads to an increase in total soil volume and a decrease in bulk density.

[#257] Land capability class restricted to recreation, wildlife, water supply, or aesthetic purposes is
Correct Answer

(B) VIII

Explanation

Solution: Land capability class restricted to recreation, wildlife, water supply, or aesthetic purposes is VIII. Land capability classification is a system of grouping soils primarily based on their capability to produce commonly cultivated crops and pasture plants without deteriorating over a long period.

[#258] Match the following columns: Column I Column II a. Nitrogen 1. Apatite b. Phosphorus 2. Pyrite c. Potassium 3. Organics d. Sulphur 4. Mica
Correct Answer

(B) a-3, b-1, c-4, d-2

Explanation

Solution: Organic Nitrogen is the term used to describe a nitrogen compound that has its origin in living material. Apatite is the name of a group of phosphate minerals with similar chemical compositions and physical properties. Mica is a hydrated phyllosilicate mineral of aluminum and potassium. The mineral pyrite is iron sulphide, it is the most abundant sulfide mineral.

[#259] Which bacteria can fix N under acidic condition?
Correct Answer

(C) Both A and B

Explanation

Solution: Both the bacteria Beijernckia and Derxia can fix N under acidic conditions. Beijerinckia is characterized as nonsymbiotic, aerobic, chemoheterotrophic bacteria with the ability to fix atmospheric nitrogen. It is aerobic-free living nitrogen-fixing bacteria.

[#260] Pedoturbation is the process of . . . . . . . .
Correct Answer

(D) Mixing of the soil

Explanation

Solution: Pedoturbation is the natural process of mixing the soil. The major process includes digging by animals, uprooting of trees, swelling of clay and downslope movement under gravity. It is synonymous with soil mixing and leads to a homogenization of the solum to various degrees.