Correct Answer: all of the above
Explanation: Irrigation becomes imperative in regions experiencing less rainfall, as it helps supplement the water needs of crops. Additionally, non-uniform rainfall patterns can leave certain areas parched, requiring irrigation. Commercial crops often demand precise water management, making irrigation essential for their successful cultivation. Therefore, the correct answer is (d) all of the above, as all these factors contribute to the necessity of irrigation in agriculture.
Correct Answer: is the percentage of culturable commanded area proposed to be irrigated annually
Explanation: Intensity of irrigation refers to the proportion of cultivable land that is planned for irrigation in a given period, expressed as a percentage. It is a crucial parameter in water resource management and agricultural planning. Option (a) correctly defines intensity of irrigation, making it the correct answer.
Correct Answer: hygroscopic water
Explanation: Hygroscopic water refers to the moisture present on the surface of soil particles that cannot move by gravity or capillary action. It can only be expelled through the application of heat. This type of water is crucial for plant growth as it influences soil structure and nutrient availability.
Correct Answer: capillary water
Explanation: Capillary water is the portion of soil water that is held in the soil against the force of gravity. Plants primarily utilize capillary water for their growth and metabolic processes. It moves upward through the soil due to capillary action and is essential for maintaining plant turgor pressure.
Correct Answer: lies above the water table at every point
Explanation: The top of the capillary zone is the level in the soil where capillary rise occurs. Importantly, it is situated above the water table, allowing water to move upwards through the soil against the force of gravity. This capillary action supports the availability of water to plants in the root zone.
Correct Answer: absorption
Explanation: During the infiltration of water below the ground surface, the predominant process is absorption. Absorption refers to the movement of water into the soil and its uptake by soil particles and plant roots. This is a critical phase in the water cycle, contributing to groundwater recharge.
Correct Answer: arid zone
Explanation: An arid zone is characterized by a severe lack of natural water resources for agriculture. In such regions, precipitation is minimal, and the available water is often insufficient to support successful crop cultivation without the aid of artificial irrigation.
Correct Answer: semi-arid zone
Explanation: The semi-arid zone represents an area with moderate water availability, allowing for the cultivation of certain crops without the necessity of irrigation. While not as arid as true desert regions, these areas still require careful water management for successful agriculture.
Correct Answer: water is under pressure between two impervious strata
Explanation: An artesian aquifer is characterized by water being confined between two impermeable layers, creating pressure. When a well is drilled into such an aquifer, the water can rise to the surface without external pumping due to the natural pressure within the aquifer.
Correct Answer: free aquifer
Explanation: An unconfined aquifer is often referred to as a free aquifer. In this type of aquifer, the water table is not confined by impermeable layers, allowing water to move freely in response to natural gradients.
Correct Answer: sick well
Explanation: A well that experiences a decrease in discharge by the designed amount is termed a sick well. This reduction in discharge may be attributed to various factors, such as changes in the aquifer or well conditions.
Correct Answer: percussion method
Explanation: When drilling a tube well in compacted rock materials, the percussion method is commonly employed. This method involves the use of repetitive blows or impacts to break the rock and facilitate drilling.
Correct Answer: black cotton soil
Explanation: Percolation loss, which refers to the downward movement of water through the soil, is generally lower in black cotton soil compared to sandy or silty soils. The clayey nature of black cotton soil restricts rapid water movement.
Correct Answer: fertilizing agent
Explanation: Silt, when present in soil, can act as a fertilizing agent. It contributes to soil fertility by enhancing its structure, retaining moisture, and providing essential nutrients for plant growth.
Correct Answer: safe yield
Explanation: Safe yield represents the maximum quantity of water that a reservoir can reliably supply during the worst dry period. It ensures sustainable water management and helps in planning for water availability under challenging conditions.
Correct Answer: 350 Ha
Explanation: Culturable Command Area (CCA) is the area that can be effectively irrigated. It is calculated by subtracting the area occupied by crops that don’t require irrigation (barren land) from the Gross Command Area (GCA). Therefore, CCA = GCA – barren land = 400 Ha – 50 Ha = 350 Ha. The correct answer is (d) 350 Ha.
Correct Answer: water stored in the soil within the root zone of the crop
Explanation: Effective precipitation for a crop refers to the water stored in the soil within the root zone of the crop. It is the water available to the crop for its growth and development. Therefore, the correct answer is (a).
Correct Answer: sprinkler irrigation
Explanation: In situations with water scarcity and high pressure, sprinkler irrigation is a suitable method. It involves spraying water over the crops, making efficient use of limited water resources. Therefore, the correct answer is (d) sprinkler irrigation.
Correct Answer: sprinkler irrigation
Explanation: In undulating sandy fields, where uniform water distribution is essential, sprinkler irrigation is the most suitable method. It ensures that water is evenly applied over the crops, promoting optimal growth. Therefore, the correct answer is (c) sprinkler irrigation.
Correct Answer: drip irrigation
Explanation: Drip irrigation is the most appropriate method during a low quantity of water. It involves delivering water directly to the root zone of plants, minimizing water wastage and ensuring efficient use. Therefore, the correct answer is (b) drip irrigation.
Correct Answer: check flooding
Explanation: The most commonly adopted method of irrigation for cereal crops is check flooding. This method involves dividing the field into smaller sections or checks, allowing water to be applied evenly across the entire field. Therefore, the correct answer is (c) check flooding.
Correct Answer: basin irrigation
Explanation: Basin irrigation is the method where land is surrounded by natural or artificial banks, and water is flooded into the enclosed area. This method is often used in orchards or for crops that benefit from controlled flooding. Therefore, the correct answer is (c) basin irrigation.
Correct Answer: effluent irrigation
Explanation: Irrigation with sewage from a town is referred to as effluent irrigation. It involves using treated or untreated wastewater for agricultural purposes. Therefore, the correct answer is (a) effluent irrigation.
Correct Answer: check flooding
Explanation: On rolling land, the most suitable method of applying water is check flooding. This method allows for controlled water distribution on slopes, preventing excessive runoff and ensuring uniform coverage. Therefore, the correct answer is (a) check flooding.
Correct Answer: at the beginning of the south-west monsoon
Explanation: Kharif crops are sown at the beginning of the south-west monsoon season. These crops are typically sown in the rainy season and harvested in the winter. Therefore, the correct answer is (c) at the beginning of the south-west monsoon.
Correct Answer: leguminous crop
Explanation: Leguminous crops have the ability to fix atmospheric nitrogen in the soil through a symbiotic relationship with nitrogen-fixing bacteria in their root nodules. Therefore, the correct answer is (c) leguminous crop.
Correct Answer: long crop
Explanation: A crop that takes more than 4 months to mature is termed a long crop. This category includes crops with an extended growth period before reaching maturity. Therefore, the correct answer is (b) long crop.
Correct Answer: in rabi season to kharif season
Explanation: Crop ratio is the ratio of the area irrigated in the rabi season to the area irrigated in the kharif season. It provides insights into the distribution of irrigation across different crop seasons. Therefore, the correct answer is (a) in rabi season to kharif season.
Correct Answer: groundnut
Explanation: Groundnut is not a Rabi crop; it is a Kharif crop. Rabi crops are sown in the winter season and harvested in the spring. Therefore, the correct answer is (b) groundnut.
Correct Answer: groundnut
Explanation: Groundnut is a leguminous crop. Leguminous crops have the ability to fix atmospheric nitrogen through symbiotic relationships with nitrogen-fixing bacteria in their root nodules. Therefore, the correct answer is (c) groundnut.
Correct Answer: none of the above
Explanation: Rabi crops are sown in the winter season and harvested in the spring. Groundnut and sugar cane are Kharif crops, while bajra is a Kharif or summer crop. Therefore, none of the options listed is a Rabi crop.
Correct Answer: all of the above
Explanation: Waterlogging can occur due to over-irrigation, inadequate drainage, or seepage from adjoining reservoirs. All the options mentioned contribute to the potential for waterlogging.
Correct Answer: the soil pores are saturated up to the top
Explanation: In waterlogged lands, the soil pores are saturated up to the surface, leading to reduced oxygen availability for plant roots. This condition can negatively impact plant growth.
Correct Answer: all of the above
Explanation: A land is considered waterlogged when the permanent wilting point is reached, gravity drainage has ceased, and the capillary fringe reaches the root zone of plants. All these factors contribute to waterlogging.
Correct Answer: all of the above
Explanation: Waterlogging can be reduced by providing canal lining, intercepting drains, and controlling the intensity of irrigation. These measures help in better water management.
Correct Answer: all of the above
Explanation: Waterlogging of fields can lead to plant diseases, the growth of water weeds, and the rise of salt in the surface layer. All these factors are disadvantages associated with waterlogging.
Correct Answer: increases
Explanation: As the salinity of water increases, the electrical conductivity also increases. Salts in water conduct electricity, and higher salinity leads to higher electrical conductivity.
Correct Answer: high salinity water
Explanation: An electrical conductivity between 750 to 2250 micro mhos/cm is classified as high salinity water. This indicates a relatively high concentration of salts.
Correct Answer: medium sodium water
Explanation: A sodium-absorption ratio between 10 to 18 is classified as medium sodium water. This ratio provides information about the sodium content in relation to other cations.
Correct Answer: Na+ / √[(Ca++ + MG++) / 2]
Explanation: The sodium absorption ratio (SAR) is defined as Na+ / √[(Ca++ + MG++) / 2]. It measures the proportion of sodium ions relative to calcium and magnesium ions in the soil.
Correct Answer: medium sodium water
Explanation: The classification is based on the sodium-absorption ratio (SAR). In this case, the SAR falls between 10 to 18, categorizing it as medium sodium water.
Correct Answer: 2 ppm
Explanation: The concentration of boron in irrigation water should be limited to 2 ppm to avoid adverse effects on plants. Excessive boron can be toxic to many crops.
Correct Answer: sodium carbonate
Explanation: Sodium carbonate in water can be harmful for cultivation purposes. It contributes to the salinity of water and may negatively impact soil quality.
Correct Answer: 11
Explanation: The fertility of the soil is adversely affected when the pH value is more than 11. Extremely high pH levels can limit nutrient availability to plants.
Correct Answer: between 6 and 8.5
Explanation: For irrigation purposes, the pH value of water should ideally be between 6 and 8.5. This range is considered suitable for most crops.
Correct Answer: Depth of water on the irrigated area
Explanation: The consumptive use of water for a crop is measured in terms of the depth of water on the irrigated area. It represents the amount of water utilized by the crop during its growth cycle.
Correct Answer: Evapo-transpiration
Explanation: Crop water consumption is proportional to evapo-transpiration, which includes the sum of water transpired by plants and evaporated from the soil surface. Effective rainfall and seepage can also contribute to crop water availability.
Correct Answer: Duty
Explanation: The ratio of the total volume of water delivered to a crop to the area on which it has been spread is known as duty. It is a measure of water distribution efficiency.
Correct Answer: Base period
Explanation: The time for which a crop occupies a field to attain its maturity is known as the base period. It is a critical factor in determining the water requirements of the crop.
Correct Answer: Days
Explanation: The base period for any crop is typically measured in days. It represents the duration from sowing to harvesting when the crop is actively growing and utilizing water.
Correct Answer: Less than the crop period
Explanation: The numerical value of the base period is generally less than the total crop period. It specifically refers to the period when the crop is actively growing and water is a critical factor.
Correct Answer: Δ = 8.64 B / D
Explanation: The relation between duty (D) and base period (B) is given by Δ = 8.64 B / D, where Δ represents delta.
Correct Answer: 68 cm
Explanation: Delta (Δ) can be calculated using the formula Δ = 8.64 B / D. Substituting B = 110 days and D = 1400 he/cumec, Δ = 8.64 * 110 / 1400 = 0.68 m or 68 cm.
Correct Answer: On the field
Explanation: The duty is largest on the field, representing the efficiency of water use at the point of application to the crops.
Correct Answer: Watercourse
Explanation: The outlet discharge factor is the duty at the head of the watercourse, indicating the efficiency of water delivery to the field.
Correct Answer: 637 hectares/m³/sec
Explanation: The outlet factor is calculated as the product of kor depth and kor period. In this case, it is 19 cm * 14 days = 266 hectares/m³/sec. The correct answer is not provided in the options.
Correct Answer: 200 cm
Explanation: Delta (Δ) can be calculated using the formula Δ = 8.64 B / D. Substituting B = 100 days and D = 432 he/cumec, Δ = 8.64* 100 / 432 = 2 m or 200 cm.
Correct Answer: 120 cm
Explanation: The average delta for a rice crop, considering various conditions, is approximately 120 cm.
Correct Answer: 90 cm
Explanation: In rice, the depth of the root zone is generally around 90 cm.
Correct Answer: 19 cm
Explanation: The optimum depth of kor watering for a rice crop is considered to be around 19 cm.
Correct Answer: 13.5 cm
Explanation: The optimum depth of kor watering for wheat in the plains or terai is considered to be around 13.5 cm.
Correct Answer: Water Application Efficiency
Explanation: Water application efficiency is the ratio of the quantity of water stored in the root zone of the crops to the quantity of water actually delivered in the field.
Correct Answer: Leaching
Explanation: Leaching is the process that washes out salts from the upper zone of the soil, helping in the removal of excess salts.
Correct Answer: Reclamation
Explanation: Reclamation is the process by which unculturable soil is made culturable, often involving the improvement of soil fertility and structure.
Correct Answer: Efflorescence
Explanation: Efflorescence is the phenomenon where salts come up in solution and form a layer of crust on the soil surface after the evaporation of water.
Correct Answer: Demineralization
Explanation: In an ion exchange process where ions are transported from water to a solid, and the ion-exchange media is either a fixed or fluidized bed, the process is termed as demineralization.
Correct Answer: Low with large gates
Explanation: In a barrage, the crest level is typically kept low with large gates to control and regulate water flow.
Correct Answer: All of the above
Explanation: A hydraulic structure is designed to withstand various factors, including seepage, hydraulic jump, and hydraulic pressure.
Correct Answer: Trough stage of the river
Explanation: The most suitable location of a canal headwork is generally at the trough stage of the river, where the water level is relatively stable.
Correct Answer: Regulate the intake of water into the canal
Explanation: Diversion headworks are constructed to regulate the intake of water into the canal from a river or source.
Correct Answer: To raise water level
Explanation: The main function of the diversion headworks of a canal from a river is to raise the water level, facilitating the diversion of water into the canal.
Correct Answer: All of the above
Explanation: The distributory head regulator serves multiple functions, including regulating the supply, controlling silt entry, and serving as a meter for discharge measurement.
Correct Answer: Fish ladder
Explanation: A fish ladder is a device provided near weirs or dams to facilitate the migration of fish upstream or downstream around the barriers.
Correct Answer: All of the above
Explanation: A regulator provided with under sluices for the escape of washout of sand-laden bottom water can be referred to as a silt regulator, silt extractor, or silt ejector.
Correct Answer: Silt excluder
Explanation: A silt regulator located at the head of a channel, designed to exclude or prevent silt entry, is called a silt excluder.
Correct Answer: Silt Excluder
Explanation: After entering the canal, sediments are removed by the silt excluder, which is designed to exclude or prevent the entry of silt into the canal.
Correct Answer: River bed down stream of the head regulator
Explanation: Silt excluders are constructed on the river bed downstream of the head regulator to prevent the entry of silt into the canal.
Correct Answer: One divide wall and two under sluice
Explanation: When two canals take off from each bank of a river, there will be one divide wall and two under sluices to control and regulate the flow.
Correct Answer: Head works – Branch canal – Main canal – Distributary
Explanation: The correct sequence of the parts of a canal system is head works, branch canal, main canal, and distributary.
Correct Answer: Distributary Head Regulator
Explanation: The supply passing down the parent channel is controlled by the distributary head regulator, which regulates the flow into the distributary.
Correct Answer: Downstream of the offtake
Explanation: A cross regulator is provided on the main canal downstream of the offtake to control the flow and regulate the water supply.
Correct Answer: All of the above
Explanation: The canal head regulator is provided at the head of the offtaking canal to regulate water supply, control silt entry, and prevent river floods from entering the canal.
Correct Answer: All of the above
Explanation: Tail race is a channel conducting water away from a water wheel, has a gradient steeper than that of the canal, and is the channel between the silt extractor and the river through which escape water is discharged.
Correct Answer: 110°
Explanation: The angle between the head regulator and the water is generally kept at 110° for the smooth entry of water into the canal.
Correct Answer: Perennial Canal
Explanation: A canal designed to irrigate throughout the year is known as a perennial canal.
Correct Answer: Perennial Canal
Explanation: Canals taken off from ice-fed perennial rivers are referred to as perennial canals.
Correct Answer: Ditch Canal
Explanation: A canal constructed by the side of and generally parallel to the parent canal with a different bed slope is called a ditch canal.
Correct Answer: Side Slope Canal
Explanation: A canal aligned at right angles to the contour is known as a side slope canal.
Correct Answer: Side Slope and Watershed
Explanation: The group of canals which avoid cross drainage work includes side slope and watershed canals.
Correct Answer: Contour Canal
Explanation: Single bank canal is another name for a contour canal.
Correct Answer: Inundation Canal
Explanation: Canals taking off from a river with or without a head regulator and used for the diversion of floodwaters are called inundation canals. These canals help manage excess water during periods of high flow.
Correct Answer: Inundation Canal
Explanation: An inundation canal is typically used for the diversion of floodwaters from a river. It helps control and manage the excess water during periods of flooding.
Correct Answer: Drain Canal
Explanation: A drain canal is used to drain off water from waterlogged areas, helping to improve the drainage conditions in those areas.
Correct Answer: The Ridge Line
Explanation: The most desirable alignment of an irrigation canal is along the ridge line. This alignment helps in efficient water distribution and management.
Correct Answer: All of the Above
Explanation: A contour canal is aligned parallel to the contour of the area, making it suitable for hilly terrain. It helps in irrigation on both sides, enhancing water distribution.
Correct Answer: A few cm above the ground level
Explanation: In a gravity canal, the Full Supply Level (F.S.L) is typically maintained a few centimeters above the ground level. This ensures a consistent and controlled flow of water.
Correct Answer: All of the Above
Explanation: The dead storage in a reservoir is provided to accumulate sediment, mitigate floods, and increase the useful life period of the reservoir. It serves multiple purposes.
Correct Answer: Decreases
Explanation: As the coefficient of friction increases, the velocity of water in a canal decreases. Increased friction results in a reduction in the speed of water flow.
Correct Answer: Critical Velocity
Explanation: The mean velocity that prevents silting or scouring in a channel throughout the year is known as critical velocity.
Correct Answer: 0.81 D
Explanation: The maximum velocity in a circular channel occurs when the depth of flow is approximately 0.81 times the diameter (0.81d).
FAQs on Irrigation Engineering MCQs for Civil Engineers
▸ What are some key topics covered in Irrigation Engineering MCQs for Civil Engineers?
Key topics include irrigation methods, water resource management, drainage systems, soil-water relationships, and irrigation design principles. For more detailed MCQs, visit gkaim.com.
▸ How can I improve my knowledge of Irrigation Engineering through MCQs?
Improving your knowledge can be achieved by regularly practicing MCQs, studying detailed solutions, and reviewing key concepts. You can access a variety of MCQs and quizzes on irrigation engineering at gkaim.com.
▸ Where can I find online MCQs for Irrigation Engineering?
You can find online MCQs for Irrigation Engineering on educational websites like gkaim.com, which offer a range of questions to help you prepare for exams and interviews.
▸ Are there any mock tests available for Irrigation Engineering MCQs?
Yes, mock tests for Irrigation Engineering MCQs are available at gkaim.com, which can help you practice and gauge your understanding of the subject.
▸ What is the significance of irrigation methods in civil engineering?
Irrigation methods are crucial in civil engineering for effective water management in agricultural projects and urban planning. Detailed MCQs on various irrigation techniques can be found at gkaim.com.
▸ How do irrigation design principles affect civil engineering projects?
Irrigation design principles impact the efficiency of water use and distribution in civil engineering projects. Understanding these principles through MCQs can be beneficial, and you can find relevant questions at gkaim.com.
▸ What are the most common types of irrigation systems covered in MCQs?
Common types of irrigation systems include drip irrigation, sprinkler systems, and surface irrigation. MCQs on these systems and their applications can be explored at gkaim.com.
▸ How does soil-water relationship influence irrigation engineering?
The soil-water relationship is vital for determining the amount and frequency of irrigation required. MCQs addressing these relationships are available at gkaim.com to help you better understand the topic.
▸ What resources are recommended for studying Irrigation Engineering MCQs?
Recommended resources include textbooks on irrigation engineering, online quizzes, and practice MCQs available at gkaim.com. These resources can provide comprehensive coverage of the subject.
▸ How can I effectively prepare for exams with Irrigation Engineering MCQs?
Effective preparation involves practicing MCQs regularly, reviewing correct answers, and studying detailed explanations. You can find practice MCQs and exam preparation materials at gkaim.com.