(SOIL SCIENCES) SSC 321: PEDOLOGY

UNIVERSITY OF NIGERIA NSUKKA

FACULTY OF AGRICULTURE

DEPARTMENT OF CROP SCIENCE

SESSION: 2013/2014

COURSE NAME: SSC 321: PEDOLOGY

1a. Using a suitable schematic diagram of a set of circles show the various soil sequences derivable from five major factors of soil formation.

b. Define each of the sequences in 1a relating each to the respective factor that gives rise to it

c. In the diagram explain why soil (S) is placed centrally in the diagram

2a. Distinguish briefly between a rock and a mineral

b. Name the various criteria often used to group the three types of rock

c. using a schematic arrow diagram state how graphite is formed from lignite

3a. With two examples of biological agents state briefly how they influence

i.              Physical weathering of rocks

ii.            Chemical weathering of rocks

3b. List all the physical agents of rock weathering and the respective region(s) of the world where each is prevalent.

3c. Using appropriate schematic diagrams illustrate the structures of 1:1 and 2:1 clay minerals; and list why 2:1 clays have more negative charges on their surfaces than 1:1 clays.    

Section B:

4. Explain the following concepts

a (i) Self mulching soils ii) Lessivage iii) Pedoturbation iv) Lithological discontinuity v) lascustrine vi) “Time zero” in soil formation

b. What are the implications of illuviation/Eluviation phenomena for agricultural development?

5a. In pedogenesis, the influence of anthropogenic factor is indispensable. Explain

b. State and explain fully five importance of pedology to humanity.

6. With a proper illustration and appropriate examples, explain the categories of internal processes often influenced by external factors of soil formation.

UNIVERSITY OF NIGERIA, NSUKKA

FACULTY OF AGRICULTURE

DEPARTMENT OF SOIL SCIENCE

FIRST SEMESTER EXAMINATION, 2012/2013 SECTION

SSC 321 (Pedolody)

Answer a total five Questions in all

Time Allowed: 2 hrs

Section A: Answer any two questions

1.             (a) Explain how the process of the formation of three rock types influence their characteristics

(b) List and explain the major factors that influence the rate of rock weathering in a name environment

(C) list five rock characteristic that vary easily transferred to the soil formed from parent materials originating from them

2.             (a) What is Isomorphus substitution?

(b) Explain briefly why 2 ratio 1 clay have more cation exchange capacity than I ratio 1 clay

 (c) What are Self-mulching soils?

3.             . Distinguish the following (i) active and passive factors and soil formation (ii) In-situ and transported parent materials (iii) zonal and azonal soil (iV) alluviun and colluvin

 (b) list the soil properties that are by topography

SECTION B Answer all three question

4.             List the 11 odor of the USDA soil taxonomy and used only a phrase to express the major differentiating characteristic

(b) Correlates each of the 11 soil orders to at least one soil unit of the FAO/ UNESCO soil mapmof the world

5.             The importance of Pedology to agriculture cannot be over emphasized discuss using five example.

6.             With a proper illustration explain the categories of internal processes often influenced by external factors of soil formation

UNIVERSITY OF NIGERIA, NSUKKA

FACULTY OF AGRICULTURE

DEPARTMENT OF SOIL SCIENCE

FIRST SEMESTER EXAMINATION, 2010/2011 SESSION

Course: SSC 321 (Pedolody)

Time 2hrs

Instruction: Answer any 5 question in all, at least 2 from section

SECTION A (at least 2 question)

1.             Compare and castrate the three type of rock under the following a. mode of formation b. characteristic c. the parent materials and subsequently the soil they gave rise to

2.             What  are clay minerals give examples

(b) State the roll of clay mineral in both physical and chemical fertility of the soil.

(c) Explain the concept of self mulching soil

3.             List the advantages of soil classification

(b) Why is USDA soil taxonomy a systematic classification system, why the FOA UNESCO map legend is not?

( C) Give a brief description of all the soil order of soil taxonomy which are likely to be found Nigeria and list those not likely to be found in Nigeria

SECTION B (at least 2 questions)

4.             Man is both an agent of soil formation order soil degradation. Fully explain citing example.

5.             What are the implication of illuviation/ elluviation phenomena in plant growth

(b) Write short note on (i) lessivage (ii) lithological discontinuity (iii) lacustrine (iv) soil color

6.             Soil is a three dimensional entity and an open system. Discuss