ARUNACHAllPRADESH lPUlBUC SERVICE COMMISSION

3 (Three) hours Full marks: 100 (GiD"OUp is compulsory. Attempt any FOUR questionsfrom Group
GROlUP
(This Group is COMPULSORy)

10x2=20
a. What is soil? How it is different from land.
b. Write different fraction of soil composition.
c. Define soil texture. Which textual class is considered to be most ideal for growing upland
crops?
d. What is soil air? How it is different from atmosphere.
e. What is Darcy's Law? Deduce it mathematically for saturated flow in soil.
f. Write the basic concept of soil mineral.
g. Give the major reasons of soil erosion in Arunachal Pradesh.
h. How soil pH affects on growing plants.
i. What is suitable pH for growing forest crops?
j. What is humus? Write down the role of humus in soil.
k What do you mean by Green Manuring? Write down the methods of Green Manuring with
suitable example.

1. What is leg-haemoglobin? Discuss the role ofleg-haemoglobin.
GROlUP -18l (All1lswer amy F01llllt'.)
Attempt any 8 (eight) 2.5x8=20
a.
What is soil moisture? Describe the importance of soil moisture constant.

b.
Write about the different classes of soil water.

c.
Explain the movement ofwater in soil.

d.
Write the classification of organic matter with the suitable example.

e.
How humus form in soil in different environment?

f.
Write the principle of soil organic matter estimation.

g.
What is humic substance? How does it bind the soil particles?

h.
AW= Fe-PWP-explain the situation in soil.

i.
How do you estimate and maintain field capacity in a field growing crops?

j.
What are the erosion control measures on hilly terrain with more than 30% slope?


Q.3. Attempt ally:; (five) (Write short notes on any five ofthe following)
a.
Master horizon

b.
Denitrification

c.
AmorphOUS clay



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d.
Afforestation

e.
pH dependent charges

f.
Soil structure


Q. 111. Attempt 41 (folUr) 5x4=20
a.
What do you mean by carbon sequestration? Write the importance of carbon sequestration in carbon budgeting of hilly areas.

b.
What is C:N ratio? Explain the role of N ratio in soil fertility.

c.
Write the forms of water movement in soil. State the differences between saturated flow
and unsaturated flow of water.


d.
Define soil colloids. Write the phases of soil colloids with suitable example.

e.
What is parent material? How it controls the composition of soil?


Q. 5. Attempt lmy 2 10x2=20
a.
What is soil biomass? Give an account of major microorganism present in forest land,
cultivated land and grazing land.


b.
What is biological nitrogen fixation? Write about different group of nitrogen fixer with
example.


c.
Explain the classification of soil micro organism on the basis oxygen, temperature and mpde of nutrition.



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Q. 6. Attempt lllJrl.y 41 (four)
a.
Define nitrification. Write its significances in agriculture.

b.
What are the factors affecting organic matter decomposition

c.
Describe the most suitable method of soil texture evaluation in field.

d.
What is VAM? Write the roles of VAM in plant nutrition.

e.
Define ammonification. Describe the pathway of transformation of amino acids, amines and other organic nitrogenous compound to NH4+


Q.7. Attempt any 2 101.2=20
a.
What do you mean by land capability classification? Describe the major factors determining Land capability classification. Discuss the limitation of each class.

b.
What is soil survey? Why it is important? Write about the detail soil survey method?

c.
What are the types of soil colloids? Justify the importance of silicate clays in agriculture.


Q. 8. What do you mean by soil profile? Give a clear diagrammatic description of a typical soil profile. Distinguish Podzolisation from Laterisation from pedogenic points ofview. 20
Q.9. What is watershed management? Write the objectives ofwatershed management practices.
Discuss the socio-economic aspects of a model watershed management project.

20
Q.l0. What is soil erosion? Draw the basic concept of a model watershed suitable to protect river, channel and hill erosion in your region.
20



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