Soil Science - Study Mode

[#696] Which chemical is used as extractant during sulfur estimation by Chesnin & Yein method?
Correct Answer

(C) CaCl 2

Explanation

Solution: Calcium chloride (CaCl 2 ) is the chemical used as an extractant during Sulphur estimation by Chesnin & Yein method. Chesnin & Yein has given knowledge of spatial variability of soil properties, the spatial distribution of specific organic matter, and nutrient management like available Sulphur or available potassium and many other essential plant elements.

[#697] The external surface area of 1 g of colloidal clay is at least . . . . . . . . times that of 1 g of coarse sand
Correct Answer

(C) 1000

Explanation

Solution: The external surface area of 1 g of colloidal clay is at least 1000 times that of 1 g of coarse sand. This is because of the small size of the clay particles whereas the size of the sand is quite bigger than clay. Particles less than 0.001 mm in size possess colloidal properties and are known as soil colloids and these are the finer size fractions of the clay soil.

[#698] Capillary pores are
Correct Answer

(B) < 15μ

Explanation

Solution: Capillary pores are the microscopic channels within hydrated paste that will draw liquid water due to surface tension. Capillary pores are at least 1 μm in diameter and it is in the range of less than 15 μ. Capillary porosity is determined by finding the volume of water retained in the soil at 50 cm tension.

[#699] Which of the following method will be followed where information are unavailable for research purpose?
Correct Answer

(C) Survey

Explanation

Solution: The survey is the method that will be followed to gather information in the case where information is unavailable for research purposes. The survey is a research method for collecting data from a predefined group of respondents to gain information and insights into various topics of interest.

[#700] Almost 95% of Indian soils are low or medium in
Correct Answer

(B) Phosphorus

Explanation

Solution: The soil of our country is rich in clay particles and has a neutral to slightly alkaline reaction. The soil is rich in bases, lime and calcium. Almost 95% of Indian soil type is low or medium in Phosphorus. Approx. 49.3% of districts and Union territories are low in available P, 48.8% are medium and only 1.9% are high.