Soil Science - Study Mode

[#576] Dispersion of colloidal clay is caused by
Correct Answer

(A) Na

Explanation

Solution: Dispersion of colloidal clay is caused by Sodium . Dispersion is a purely chemical phenomenon, driven by the balance of cations in the soil. The inorganic or clay colloidal complex of soils occurs as too fine particles and the organic colloidal complex happens in the form of humus particles. The general balance between calcium and magnesium to sodium determines dispersion.

[#577] From which group urea belongs to
Correct Answer

(A) Amide

Explanation

Solution: Urea also known as carbamide, is an organic compound with the chemical formula CO(NH 2 ) 2 . Urea belongs to the Amide group. This amide has two NH 2 groups joined by a carbonyl (C=O) functional group. Urea has the highest nitrogen content of all solid nitrogenous fertilizers in common use.

[#578] A fertile soil is one which has more
Correct Answer

(C) Available nutrients

Explanation

Solution: Soil fertility refers to the ability of soil to sustain agricultural plant growth, provide plant habitat and result in sustained and consistent yields of high quality. Fertile soil has more available nutrients and water in adequate amounts and proportions for plant growth and reproduction.

[#579] If the moisture content of 0-15 cm, soil layer is 22%, then the moisture content in depth will be
Correct Answer

(B) 3.3 cm

Explanation

Solution: If the moisture content of 0 - 15 cm, the soil layer is 22%, then the moisture content in depth will be 3.3 cm . Soil moisture content was lower in topsoil (0 - 20 cm) compared to deeper soil (40 - 80cm). And the moisture content is then calculated by subtracting the weight of the dry soil from the weight of the moist soil and then dividing by the weight of the dry soil.

[#580] Which one of the following is the biological method of soil conservation
Correct Answer

(C) Mulching

Explanation

Solution: Mulching is one of the biological methods of soil conservation. Mulching is the placement of any organic or inorganic material over the top of a soil surface to protect it. It helps in the conservation of soil moisture, improves soil fertility and health of the soil, reduces weed growth, and enhances the visual appeal of the area.