1. : The main purpose of erosion control structures is:
(A) To increase runoff velocity
(B) To reduce soil loss and stabilize land
(C) To promote gully formation
(D) To remove vegetation cover
2. : A check dam is constructed to:
(A) Increase wind erosion
(B) Reduce gully erosion and store water
(C) Increase slope steepness
(D) Block afforestation
3. : Contour bunds are constructed:
(A) Across the slope along contour lines
(B) Up and down the slope
(C) Parallel to wind direction
(D) In flat plains only
4. : Which erosion control structure is most effective on steep slopes?
(A) Bench terraces
(B) Contour bunds
(C) Strip cropping
(D) Windbreaks
5. : Loose boulder check dams are usually built in:
(A) Streams with high discharge
(B) Small gullies with low runoff
(C) Large rivers
(D) Coastal areas
6. : Vegetative barriers like grass strips are used to:
(A) Accelerate runoff
(B) Reduce sheet and rill erosion
(C) Increase soil compaction
(D) Reduce infiltration
7. : Gabion structures are made of:
(A) Plastic nets
(B) Woven wire mesh filled with stones
(C) Wooden logs
(D) Soil only
8. : Drop spillways are constructed to:
(A) Control stream bank erosion
(B) Safely dispose of excess runoff with a vertical drop
(C) Reduce wind velocity
(D) Increase groundwater salinity
9. : The most suitable structure for controlling wind erosion is:
(A) Check dam
(B) Shelterbelt
(C) Contour bund
(D) Percolation tank
10. : A percolation pond is mainly constructed for:
(A) Groundwater recharge and erosion control
(B) Increasing soil erosion
(C) Flooding
(D) Irrigation only
11. : Contour trenches are effective in:
(A) Steep rocky slopes
(B) Gentle to moderate slopes for water harvesting
(C) Flat plains
(D) Sandy deserts only
12. : Drop structures are also known as:
(A) Grade control structures
(B) Wind barriers
(C) Bench terraces
(D) Gully plugs
13. : Check dams reduce erosion by:
(A) Reducing runoff velocity and trapping sediments
(B) Increasing runoff speed
(C) Removing vegetation
(D) Increasing slope gradient
14. : Brushwood check dams are usually constructed using:
(A) Grass and weeds
(B) Tree branches and twigs
(C) Plastic bags
(D) Soil compaction only
15. : A drop spillway is best suited for:
(A) Small gully heads
(B) Large rivers
(C) Coastal erosion
(D) Desert dunes
16. : Contour stone bunds are widely used in:
(A) Arid and semi-arid regions
(B) Forested areas
(C) Wetlands
(D) Coastal regions
17. : Ravine reclamation is commonly done using:
(A) Check dams and afforestation
(B) Strip cropping
(C) Bench terraces
(D) Flood irrigation
18. : Drop inlet spillways are used for:
(A) Diverting wind flow
(B) Safely carrying runoff from higher to lower levels
(C) Reducing groundwater recharge
(D) Blocking flood plains
19. : Earthen bunds are most suitable for:
(A) Light rainfall areas with gentle slopes
(B) High rainfall areas with steep slopes
(C) Coastal regions
(D) Desert dunes
20. : The cheapest temporary erosion control structure in gullies is:
(A) Gabion check dam
(B) Brushwood dam
(C) Drop spillway
(D) Concrete check dam
21. : Drop structures help in:
(A) Stabilizing gully heads
(B) Increasing sheet erosion
(C) Removing groundwater
(D) Increasing wind speed
22. : Which erosion control structure also improves groundwater recharge?
(A) Check dam
(B) Contour bund
(C) Percolation pond
(D) All of these
23. : Grassed waterways are provided in fields to:
(A) Allow safe disposal of excess runoff without erosion
(B) Reduce infiltration
(C) Increase sheet erosion
(D) Block drainage
24. : Which structure is permanent and costly but very effective for gully control?
(A) Concrete check dam
(B) Brushwood check dam
(C) Loose stone dam
(D) Contour trench
25. : The choice of erosion control structure mainly depends on:
(A) Soil type, rainfall, slope, and land use
(B) Fertilizer availability
(C) Distance from markets
(D) Cost of seeds