Soil and Water Erosion - Soil and Water Conservation Engineering - Agricultural Engineering Previous Year Questions

1

2007 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2007

The soil loss from a field with 5% slope and for crop management factor of 0.25 is 44.80 Mg ha⁻¹. Contouring along with crop management factor of 0.15 is adopted as the soil conservation measure in the field. The changed soil loss from the field is

A

1.61 Mg ha⁻¹

B

2.68 Mg ha⁻¹

C

16.12 Mg ha⁻¹

D

26.87 Mg ha⁻¹

Open complete paper

2

2008 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2008

The following design parameters of contour bunds constructed on a land of 4% slope are given: V.I. = 1.2 m, base width = 2.5 m, top width = 0.5 m, height = 1.0 m. Assuming the length for side and lateral bunds as 30% of the length of contour bunds, the land area lost due to bunding is

A

0.156%

B

2.50%

C

10.83%

D

12.52%

Open complete paper

3

2008 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2008

If W is the width of a bench terrace constructed on a land of slope S, then the drop (D) between two consecutive bench terraces for a riser slope of ½ : 1 is given by

A

D = WS/(100 – S)

B

D = WS/(200 – S)

C

D = 2WS/(200 – S)

D

D = 2WS/(100 – S)

Open complete paper

4

2008 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2008

The depth of impounding immediately behind the contour bund is

A

0.32 m

B

0.42 m

C

0.52 m

D

0.62 m

Open complete paper

5

2009 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2009

Contour bund is constructed on a land with S per cent slope. If the length of each contour bund is L and vertical interval is D, then the number of contour bunds per hectare of land area is

A

\(\frac{S}{LD}\)

B

\(\frac{LD}{S}\)

C

\(\frac{100S}{LD}\)

D

\(\frac{10^{4}S}{LD}\)

Open complete paper

6

2010 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2010

For a given watershed, the rainfall erosivity index is 1000 MJ mm ha^-1 h^-1 year^-1, soil erodibility index is 0.25 Mg ha h ha^-1 MJ^-1 mm^-1, crop management factor is 0.75, conservation practice factor is 1.0 and slope length factor is 0.2. If by certain conservation practices, the conservation practice factor is reduced to 0.7, then the reduction in soil loss, in Mg ha^-1 year^-1 is

A

9.75

B

11.25

C

11.75

D

12.25

Open complete paper

7

2011 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2011

In wind erosion process, the rate of soil movement (S) depends on wind speed (v), threshold limit of wind speed required to move the soil (\(v_m\)) and average soil particle size (d). This interrelationship is expressed as

A

\(S \propto (v - v_m)^2 d^{1/2}\)

B

\(S \propto (v - v_m)^2 d\)

C

\(S \propto (v - v_m)^3 d^{1/2}\)

D

\(S \propto (v - v_m)^3 d\)

Open complete paper

8

2011 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2011

For the eastern Himalayan region having hill slope of 16%, a bench terrace system is to be designed. It is found that the depth of cut for constructing the bench terrace cannot be more than 0.40 m due to the limitation of the soil depth. If a batter slope of ½ : 1 is proposed, the maximum possible width of the terrace and the required earthwork per hectare (assuming cut equal to fill) will be

A

3.4 m, 680 m³

B

4.6 m, 920 m³

C

4.8 m, 960 m³

D

5.0 m, 1000 m³

Open complete paper

9

2013 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2013

A 16 m high wind break is constructed to protect soil from wind erosion due to wind velocity of 18 \(\text{m s}^{-1}\) at 15 m height. The minimum wind velocity at 15 m height capable of moving the soil fraction is \(8 \text{ m s}^{-1}\). The angle of deviation of prevailing wind direction from the perpendicular to the wind break is \(30^{\circ}\). The distance of full protection from the wind break in m is

A

60.44

B

104.69

C

306.00

D

530.01

Open complete paper

10

2014 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2014

Bench terraces are to be constructed on a 15% hill slope. The batter slope is 1:1 and vertical interval is 2.5 m. The earth work in cutting is equal to filling. The quantum of earthwork in m³ ha^–1 will be

Check answer

Open complete paper

11

2014 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2014

Bench terraces are to be constructed on a 15% hill slope. The batter slope is 1:1 and vertical interval is 2.5 m. The earth work in cutting is equal to filling. The quantum of earthwork in m3 ha−1 will be

A

2656

B

2818

C

4248

D

5312

Open complete paper

12

2014 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2014

A triangular shaped grassed waterway with a longitudinal slope of 2.5% is to carry a discharge of 1.5 m3 s−1 with a permissible velocity of 1.2 m s−1. The side slope of the channel is 1.5:1 (Horizontal:Vertical). Without considering free board, the top width of the channel in m is

Check answer

Open complete paper

13

2016 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2016

Annual average soil loss from a watershed has been measured as 20 Mg ha^-1 year^-1. Watershed has 8% land slope and 84 m maximum slope length. Assume all other factors same and dimensionless exponent for slope factor is 0.5. To reduce soil loss from the watershed to 10 Mg ha^-1 year^-1, the maximum slope length in m should be __________

Check answer

Open complete paper

14

2016 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2016

The most suitable hydraulic structure for conveying water from higher elevation to lower elevation across the earthen bund is

A

Drop structure

B

Pipe drop structure

C

Chute spillway

D

Gabion structure

Open complete paper

15

2016 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2016

If the width of bench terrace is \(W\), drop \(D\) and existing land slope \(S\); then for 150% batter slope, the drop \(D\) will be

A

\(\frac{W S}{100}\)

B

\(\frac{W S}{(100-S)}\)

C

\(\frac{2 W S}{(200-S)}\)

D

\(\frac{2 W S}{(300-2 S)}\)

Open complete paper

16

2017 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2017

Remedial measure generally adopted for controlling stream-bank erosion is

A

Shelter belts

B

Spurs

C

Brushwood dams

D

Drop spillways

Open complete paper

17

2017 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2017

Bunds are to be constructed to conserve rainwater in a farm having 6% slope. If the horizontal interval between two bunds is 30 m and there is no loss of water, the required height of the bund to store rainwater from an 18 cm rainfall event with 10 years of return period in cm will be ______.

Check answer

Open complete paper

18

2018 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2018

A rectangular chute spillway is designed for gully erosion control with a drop (H) of 5 m, peak flow of 1.81 m³ s⁻¹ and maximum inlet water level of 0.81 m. Frictional head loss over the apron is 20% of H. The design height of chute blocks is equal to the depth of flow in the water way. Acceleration due to gravity (g) is 9.81 m s⁻². If coefficient of discharge of the weir section is 1.66, height of the chute blocks is ______ m.

Check answer

Open complete paper

19

2019 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2019

On a 4% land slope in a medium rainfall zone, the horizontal spacing of bunds in meter and the length of bunds per hectare in meter, respectively are

Check answer

Open complete paper

20

2020 · Agricultural Engineering · Soil and Water Conservation Engineering · Soil and Water Erosion

Agricultural Engineering (AG) 2020

The following data were used for a watershed experiencing soil erosion problem:
Rainfall Erosivity Index = 280 MJ mm ha⁻¹ h⁻¹ year⁻¹, Soil Erodibility Index = 0.38 ton ha h MJ⁻¹ mm⁻¹, Slope length = 200 m, Average slope of the land = 8%, Slope steepness factor = 0.85, Cropping management factor = 0.35, and Conservation practice factor = 0.60
If the slope length is reduced to half, percentage reduction in soil loss (round off to 2 decimal places) is ______________.

Check answer

Open complete paper