Soil Science MCQ Question and Answer | Agriculture MCQ Question

Endepedon is a diagnostic horizon characterized by the accumulation of aluminum and organic matter with or without iron. And Argillic is the mineral soil horizon that is characterized by the illuvial accumulation of layer-lattice silicate clays.
For consideration of Argillic endopedon, 1.2 times of clay content need to have than the overlying horizon.

A colloid is a glue-like organic or inorganic matter with too little particle size but a large surface area per unit mass or volume.
The size of the clay particles is the smallest. It is less than 0.002 mm in diameter.
Moreover, the size of sand is 2.0 to 0.05 mm and Silt is 0.05 to 0.002 mm.

Ammonium nitrate is a chemical compound with the chemical formula NH₄NO₃. It is a white crystalline solid consisting of ions of ammonium and nitrate. Both of them i.e. ammonium cation and nitrate anion are in 50% - 50%.
It is highly soluble in water and hygroscopic as a solid, although it does not form hydrates. It is predominantly used in agriculture as a high nitrogen fertilizer.

Phosphate rock combined with finely-divided, elemental Sulphur and Thiobacillus is combined to form a fertilizer “Biosuper”.
Biosuper is effective on soils of both low and medium phosphorus status, and also on soils differing in P retention capacity. Thiobacillus present in Biosuper oxidizes Sulphur, producing sulphates useful to plants.

A benchmark soil is one of a large extent within one or more major land resource areas that holds a key position in the soil classification system.
A benchmark soil is a reference point that is adequately characterized in terms of its properties and environmental conditions.
64 benchmark soils have been identified in the different major land resource areas of Kerala for which soil monoliths were collected.
The basic objective of this soil is to focus attention on extensively occurring soils and their agronomic concepts for wider acceptability of interpretations and extrapolations of research data.

Acis sulphate soil is the soil or sediments containing iron sulphides. Iron sulphides are micro-crystalline minerals such as pyrite that have formed naturally in soils where long-term water-logged conditions occur. When it is disturbed by drainage, lowering of water tables, or excavation, oxidation of the sulphides creates sulphuric acid which can trigger a range of flow-on effects.
Thus, the useful practice to manage acid sulphate soil is keeping the soil waterlogged.

Plant analysis is a crop management tool that has been stimulated by the increased use of scouting programs and crop consultants. The information provided through plant analysis helps farmers with decisions on the effectiveness of fertilizer, the need for additional nutrients, and planning fertilizer programs for future use.
It is required plant analysis is useful if done at an early stage.

Humus is the dark organic matter in soil that is formed by the decomposition of plant and animal matter by the act of micro-organisms i.e. bacteria and fungi. It is rich in nutrients and retains moisture in the soil.
Organic matter is humified by a combination of saprotrophic fungi, like Alternaria and Aspergillus. Whereas Trichoderma strains are used for biological control of plant disease.

Oxisols are a soil order in soil taxonomy, for their occurrence in the tropical rainforest. The main processes of soil formation of oxisols are weathering, humification and pedoturbation due to animals.
Oxisols are specified by a thick subsurface layer that contains kaolin-group clay minerals ie. Kaolinite and metal oxides in a finely textured matrix with very little or no easily weathered silicates.

Arkose is a coarse sandstone primarily made up of quartz and feldspar grains together with small amounts of mica, all moderately well sorted, slightly worn, and loosely cemented with calcite or less commonly, iron oxides.
Closely resemble granite in appearance and is frequently utilized as a building material.