Soil order characterized by excess of weathering with dominant iron and aluminium oxide clays, common in tropics is_________?

Related Mcqs:

1. If the frequency of a dominant phenotype in a stable population in 75% the frequency of the dominant allele in that population is____________________?

   A. 50%
   B. 75%
   C. 25%
   D. 40$

2. Any material such as straw, sawdust, leaves, plastic films, & loose soil that is spread upon the surface of the soil to protect the soil & plant roots from the effects of raindrops, soil crusting, freezing or evaporation:

   A. Mull
   B. Mulch
   C. Mycorrhizae
   D. Muck

   Submitted by: Shafiq Rehman

3. Most common rocks, after exposed to weathering which cover about ______% 0f the earth:

   A. metamorphic rocks
   B. Sedimentary rocks
   C. Igneous rocks
   D. Shales

   Submitted by: Shafiq Rehman

4. Weathering process-physical, chemical, and biological _______________, the rocks and minerals into simpler products which either accumulate in place or are transported to other places where they become soil parent materials?

   A. Disintegrate
   B. Disentigrate
   C. Decompose
   D. Both a & c

   Submitted by: Shafiq Rehman

5. Accumulation of Al and Fe oxides and clays coming from the upper profile layers:

   A. Zone of eluviation
   B. Zone of Illuviation
   C. Zone of evaluation
   D. None of the above

   Submitted by: Shafiq Rehman

6. Source of negative charges on silicate clays is/ are________?

   A. Exposed crystal edges
   B. Isomorphous substitution
   C. Anion exchange
   D. All of these

   Submitted by: Shafiq Rehman

7. Soil-forming minerals occurring in rocks do not contain any water, they undergo ______________ when exposed to humid conditions & break down as in chemical weathering process:

   A. Carbonation
   B. Acidification
   C. Hydration
   D. Dissolution

   Submitted by: Shafiq Rehman

8. swelling clay soils, develop cracks due to greater proportion of swelling type clays:

   A. Alfisols
   B. Ultisols
   C. Vertisols
   D. None of the above

   Submitted by: Shafiq Rehman

9. The major soil fertility problems in Pakistani soils deficiencies of N, P and Zn. Deficiencies K, Fe, and B also occur in specific crop genotypes or soil types, while deficiencies of S, Cu, and Mn are negligible. however, the common nutrient deficiencies are_________________: and some micronutrients including Mo?

   A. N, P, K
   B. Ca, Mg, S
   C. both A & B
   D. The above statement is wrong

   Submitted by: Shafiq Rehman

10. The internal & external surfaces of soil colloids are positively and or negatively charged. Mostly ____________ is dominant:

    A. Positive
    B. Negative
    C. Zero
    D. All of the above

    Submitted by: Shafiq Rehman