Deck 15: Irrigation, Soil Fertility, and Water Management

Question 1

The irrigation is necessary in an area

A)where there is a scanty rainfall
B)where the rainfall is non-uniform
C)where commercial crops require more water
D)all of the above

Answer 1

all of the above

Question 2

The infertility of the soil in water-logged areas is due to

A)inhibiting activity of the soil bacteria
B)growth of weeds
C)increasing of harmful salts
D)all of these

Answer 2

all of these

Question 3

A canal outlet should

A)be so designed that the farmer cannot temper with its functioning
B)be simple so that it can be constructed or fabricated by local masons
C)draw its fare share of silt carried by the distributing channel
D)all of the above

Answer 3

all of the above

Question 4

The moisture content of the soil, after free drainage has removed most of the gravity water, is known as

A)field capacity
B)saturation capacity
C)wilting co-efficient
D)available moisture

Question 5

A solid construction put across the river to raise its water level and divert the water into the canal, is known as

A)marginal bund
B)weir
C)barrage
D)dam

Question 6

The most economical section of a lined canal is

A)rectangular section with circular bottom for small discharges
B)triangular section with circular bottom for small discharges
C)trapezoidal section with rounded corners for higher discharges
D)none of the above
E)both (b) and (c)

Question 7

A side slope canal, cross-drainage works are completely eliminated.

Question 8

The hydrology helps in

A)predicting maximum discharge
B)deciding capacity of reservoir
C)fore casting flood
D)all of these

Question 9

A weir is generally aligned at right angle to the direction of the main river flow because

A)it is economical
B)less length of weir is required
C)it gives better discharge capacity
D)all of these

Question 10

A deflecting groyne in a river is

A)inclined towards upstream
B)perpendicular to bank
C)inclined towards downstream
D)none of these

Question 11

The method used for training of rivers is

A)guide bank
B)dyke or levee
C)groyne
D)all of these

Question 12

In a barrage, crest level is kept

A)low with large gates
B)high with large gates
C)high with small gates
D)low with small gates

Question 13

The process of loosing water from the leaves of plants, is termed as

A)surface evaporation
B)water surface evaporation
C)transpiration
D)precipitation

Question 14

A graph showing variations of discharge with time, at a particular point of a stream is known as

A)mass inflow curve
B)logistic curve
C)hydrograph
D)none of these

Question 15

The average duty for sugar-cane in hectares/cumec is

A)200
B)400
C)600
D)800

Question 16

When river flows in a plain country, its stage is known as

A)delta
B)boulder
C)trough
D)rocky

Question 17

In a syphon, the underside of the trough carrying drainage water is

A)lower than
B)higher than
C)in level with

Question 18

A land is said to be water-logged when

A)the air circulation is stopped in the root zone due to the rise in water table
B)it is submerged in flood
C)the doil pores within a depth of 40 cm are saturated
D)all of the above

Question 19

The setting for a sub-proportional outlet is

A)more
B)less
C)same

Question 20

The maximum rainfall during a short period measured in mm / hour is called mean annual rainfall.

Question 21

The time (in days) that crop takes from the instant of its sowing to that of its harvest, is known as

A)base
B)crop
C)kor

Question 22

The perimeter discharge (P-Q) relation is given by the equation

A)P = 2.25 Q^1/2
B)P = 2.25 Q^3/2
C)P = 4.75 Q^1/2
D)P = 4.75 Q^3/2

Question 23

Available moisture may be defined as the

A)moisture content at permanent wilting point
B)difference in water content of the soil between field capacity and permanent wilting
C)maximum moisture holding capacity
D)all of these

Question 24

Which of the following statement is correct?

A)The gravity water is harmful to the crops.
B)The hygroscopic water remains attached to the soil molecules by chemical bonds.
C)The capillary water is utilised by the plants.
D)all of the above

Question 25

The fall of moisture from the atmosphere to the earth surface in any form, is called

A)evaporation
B)transpiration
C)precipitation
D)none of these