Soil Science MCQ Question and Answer | Agriculture MCQ Question

Walkley and Black's method quantifies the amount of oxidizable organic matter in which organic matter is oxidized with a known amount of chromate in the presence of sulphuric acid.
This method claims to estimate organic carbon and determine the overall organic matter and the percent recovery is about 74%.

Split application refers to utilizing a sequence of two or more nutrient applications, separated by approximately three weeks or more, to a single crop to improve nutrient uptake efficiency. Therefore Nitrogen is also applied in splits just to increase its efficiency.

Ion exchange reaction is any class of chemical reaction between two substances, each consisting of positively and negatively charged species called ions that involves an exchange of one or more ionic components. Whereas cation exchange reaction involves the exchange of cations only.
The cation exchange reaction is an example of a Reversible and Equivalence reaction. It is used to replace the existing ionic nanocrystalline structure with a different metal ion.

Hygroscopic water is the water that is absorbed by moisture from the air. It forms an extremely thin tightly held film around the soil particles by surface forces.
The hygroscopic water is not available for plants and it can be retained in the soil at 31 bar.

Sulphate of Potash is the one that is recommended for potatoes. sulphate of potash contains the most efficient balance of nutrients to optimize potato yields, quality and storability.
Potash is an essential nutrient for all plants and has a major effect on the yield and quality of potatoes as well as the general health and vigour of the crop. It also helps in regulating the amount of water in the plant.

Red soil is mostly found in southeast Maharashtra. Red soil is red because of the presence of ferric oxide, it is porous and has a friable structure with a sandy to clay and loamy texture.

Black soil is mostly found in the Kerala region. It is clayey in texture and is highly fertile. This soil is rich in calcium carbonate, magnesium, potash and lime but poor in nitrogen and phosphorus.

Laterite soil is found in Tamil Nadu state in areas with high temperatures and heavy rainfall. This soil is formed by the process of intense leaching.

Decan soil is the black or alluvial soil found in central India and regions of Uttar Pradesh, deposited by the surface water and is extremely fertile.

Sandy soil is found in the desert region of Rajasthan. Sandy soil is light, warm, dry and tends to be acidic and low in nutrients.

One acre of soil to a depth of 6 inches weighs about 2 million pounds or 2 × 10⁶ Ib.
One acre of soil up to 15 cms or 6 inches would be 8,96,000 kgs.

A neutron moisture meter is a moisture meter utilizing neutron scattering. It is used to measure the water content in soil or rock. The technique is non-destructive and is sensitive to moisture in the bulk of the target material.
In the neutron moisture meter, the source of fast neutrons is both Radium and American-beryllium.

CaCl₂ solution has 2 ions of chlorine.
Stoichiometric factor 2 of Cl^-
Based on the equation, a 0.05 M CaCl₂ solution has an ionic strength of
I = 3 × 0.05 M
  = 0.15 M

S-pollution is Sulphur dioxide pollution, and Lichens is an indicators of S-pollution.
Lichens do not survive in areas polluted with Sulphur dioxide. Sulphur dioxide is a gaseous air pollutant composed of Sulphur and oxygen, formed by burning coal, oil, or diesel is burned. And this Sulphur dioxide combines with rain water and air to form sulphuric acid, which is the main component of acid rain.