Soil Science - Study Mode

[#631] Non-essential but useful nutrients for plants would include
Correct Answer

(D) Vanadium and sodium

Explanation

Solution: Vanadium and Sodium are non-essential but useful nutrients for plants. Plants require 17 essential nutrients for their growth and development, but vanadium and sodium are not on that list.
Vanadium is a multivalent redox-sensitive metal, low levels of vanadium elevate plant height, root length, and biomass production due to enhanced chlorophyll biosynthesis, seed germination and also for essential element uptake. Sodium is needed by a few varieties of plants to help concentrate carbon dioxide, but in trace amounts to promote metabolism.

[#632] Glyricidia species is used as
Correct Answer

(C) Both A and B

Explanation

Solution: Gliricidia species is a medium size leguminous tree belonging to the family Fabaceae. It is an important multipurpose legume tree and is native to tropical dry forests. The tree grows well in acidic soils with a pH of 4.5 - 6.2. This species is mainly used as Green manure and Green leaf manure. Also for fencing, fodder, firewood, intercropping and rat poison.

[#633] For Beidellite & Nontronite isomorphous substitution occur in
Correct Answer

(B) Tetrahedra

Explanation

Solution: For Beidellite & Nontronite isomorphous substitution occur in Tetrahedra . Beidellite is a mineral that is a common constituent of certain clay and consists of basic aluminosilicate with exchangeable calcium, sodium, or other cation, whereas Nontronite is the iron-rich member of clay minerals. Moreover, isomorphous substitution is the production of net native charge in clays, and this charge must be balanced by positively charged ions from the solution and helps in the retention of plant nutrients.

[#634] Sixteen nutrients are essential for
Correct Answer

(C) All crops

Explanation

Solution: Sixteen nutrients are essential for all crops to grow well, develop, reproduce and remain healthy. Carbon, hydrogen and oxygen are extracted from air and water to make up the bulk of plant weight. Nitrogen, phosphorus and potassium, are primarily essential nutrients that are very crucial for the survival of the plant. Calcium, magnesium, Sulphur, Boron, chlorine, copper, iron, manganese, molybdenum and zinc.

[#635] Inorganic parent material transported by gravity is
Correct Answer

(D) Colluvial

Explanation

Solution: Colluvial is an inorganic material transported by gravity. It is a general name for loose, unconsolidated sediments that have been deposited at the base of hillslopes by either rainwash, sheet wash, slow continuous downslope creep by unconcentrated surface runoff or sheet erosion. Thick accumulations of colluvium may preserve a rich record of long-term paleoclimatic change based on the paleosols and the remains of plants and animals.