ICSE Geography Class 10 Question Bank Chapter 7 Water Resources

ICSE Geography Class 10 Question Bank Chapter 7 Water Resources

 Questions Based on Water Resources

I. Short Answer Questions:

Question 1.
Name four surface water resources.
Answer:
Rivers, lakes, ponds, lagoons are the different surface water resources.

Question 2.
Give two main reasons why water scarcity occurs in India.
Answer:

1. Overexploitation of water sources.
2. Improper management,
3. Industrialisation and urbanisation.

Question 3.
(i) What is meant by water harvesting?
(ii) Mention any three Water harvesting systems practised in India.
Answer:
(i) Water harvesting is the activity of direct collection of rainwater the rainwater collected can be stored for direct use or can be recharged into the groundwater. They were called Khatri or Kuhl in Western Himalayas, Boalis or Dighis in the Gangetic plains, Johads in Central India, Korambu in Eastern Ghats and Zing in Ladakh.

(ii) Rain water is harvested in India by following methods :
(a) Catchments
(b) Rooftop Rain water harvesting.
(c) Check dams.

Question 4.
Why is Water harvesting needed?
Answer:
Water harvesting is needed because in India rainfall occurs during short spells of high intensity. Because of such intensities and short duration of heavy rain, most of the rain falling on the surface tends to flow away rapidly, leaving very little for the recharge of groundwater.

Question 5.
How much water is utilised by the agricultural sector in India?
Answer:
About 92% of water is utilised by the agricultural sector in India.

Question 6.
What is meant by irrigation?
Answer:
Irrigation refers to the process of watering of agricultural plants through artificial means from wells, tanks, tubewells, canals; etc.

Question 7.
Why do we need to adopt different means of irrigation?
Answer:
We need to adopt different means of irrigation for sustained agricultural production and allround development.

Question 8.
Mention the three factors based on which different means of irrigation are used.
Answer:
Different means of irrigation are utitlised in India, based on the availability of surface (river) and groundwater, relief, soils and climatic conditions.

Question 9.
Name the States in India where well irrigation is used.
Answer:
Well irrigation is used in India in states like Uttar Pradesh, Goa, Punjab, Haryana, Bihar, Rajasthan, Gujarat, Maharashtra, Madhya Pradesh, Andhra Pradesh, Karnataka and Tamil Nadu.

Question 10.
Name two states in which tubewells are extensively used. Give a reason to explain its importance as a source of irrigation.
Answer:
Uttar Pradesh and Bihar. Because

• They can irrigate large area,
• In dry period they do not dry up due to deep boring.

Question 11.
How are the fields irrigated using the Persian wheel method?
Answer:
Fields are irrigated using the Persian wheel method by a partly submerged vertical wheel with buckets attached to the rim. As the wheel is turned by draught animals rotating a geared horizontal wheel, the buckets are filled and emptied into a trough above, which carries the water to crop-sown fields.

Question 12.
Give two advantages and two disadvantages of well irrigation.
Answer:
Advantages of well irrigation:

• Wells can be dug at a very low cost which is well within the means of poor farmers.
• Water can be lifted even from great depths, by the use of pumps and tubewells.

Disadvantages of well irrigation:

• Wells depend on undergroundwater resources whose distribution varies from region to region.
• It is difficult to dig wells or bore tubewells in the hilly regions of the north and stony areas of the Peninsula.

Question 13.
Give two advantages and one disadvantage that tubewells have over surface wells.
Answer:
Advantages of tube wells

• It occupies a small area.
• Tubewells are perennial.
• Water does not get polluted.
• Tubewells irrigates 400 hectare means large area
• No manual labour is required to draw water.

Disadvantages of tubewells

• Tubewells are expensive to construct.
• It irrigates particular area.
• It causes depletion of groundwater.
• It reduces the water table.
• Power is needed to draw water.
• The region must be fertile and productive so that the cost of the construction and operation of the tube well is justified.

Question 14.
Name the two types of canals.
Answer:
Two types of canals are:

1. Inundation canals
2. Perennial canals

Question 15.
Name two states where perennial canals are widely used.
Answer:
(i) Perennial canals are used in Punjab, Haryana, Rajasthan.
(ii) (1) Low relief area.
(2) Even surface so digging is easy.
(3) Perennial rivers.

Question 16.
Why are inundation canals being converted to perennial canals? Give two reasons.
Answer:
Inundation canals are being converted to perennial canals because

• Inundation canals are taken from rivers without any regulating systems like weirs at their head while perennial canals have water in them throughout the year.
• Inundation canals are “floodwater” canals and have water in them only when the rivers is flooded during the raining season and are solely dependent on rainfall for its supply while perennial canals have water in them all the year around.
• These canals dry up in the drought.
• Inundation canals are not lined unlike perennial canals and the water in them seeps through into the surrounding area, leading to the formation of swamps.
• Since inundation canals have no regulative system at the head, they cannot be used to irrigate – areas at higher levels, unlike perennial canals.

Question 17.
Where are tanks most widely used in India? Why?
Answer:
Tanks are most widely used in India (more in South India than in North India, in states like Orissa, Andhra Pradesh, Tamil Nadu and Karnataka) because of the following reasons:

• The Deccan Plateau is a highly. Dissected one with natural depressions.
• The Deccan Plateau is a highly dissected one with natural depressions. (Anyone)

Question 18.
Mention two disadvantages of tank irrigation.
Answer:

1. Tanks get silted up soon and regular desalting is required to make these suitable for irrigation.
2. When the monsoons fail they go dry and therefore, are not dependable source of irrigation.

Question 19.
Give three disadvantages of using conventional system of irrigation.
Answer:
Disadvantages of conventional methods of irrigation:

• In the Conventional system of irrigation large quantity of water is not properly utilised.
• Crops are usually subjected to cyclic changes of flooding and water stress situations, by providing heavy irrigation at one time and leaving the fields to dry up for about 10 to 15 days. The moisture availability to the crops therefore keeps on changing. This results in poor yields in the crops.
• The fields situated in low areas always get excess water causing prolonged waterlogging. Thus, crops are subjected to waterlogging resulting in poor yields.

Question 20.
Name the three modern means of irrigation.
Answer:
Modem means of irrigation includes furrow irrigation, spray irrigation and drip irrigation.

Question 21.
Give three reasons to justify the need to conserve water?
Answer:

1. The overexploitation of underground water often results in the lowering of water table.
2. Water is basic input for agriculture. If there is shortage of water, food production will fall leading to scarcity of essential products.
3. To save the future generations from water crisis.

Question 22.
Give two reasons why tanks are used for irrigation in the Deccan.
Answer:
Tanks are used for irrigation in Deccan because of the following reasons:

• The rivers of the Deccan are not snow-fed and are mainly dependent on the rainwater.
• There are many streams which became torrential during the rany season but dry up when the rain ceases.

Question 23.
Mention two advantages of rainwater harvesting.
Answer:
The advantages of rainwater harvesting are –

• It reduces groundwater pollution,
• It reduces soil erosion.
• It meets the increasing demand for water and supplements household requirement of water.
• It reduces surface runoff,
• It avoids flooding of roads.
• It raises the groundwater table by adding to groundwater reserves.
• It conserves water.
• It improves the quality of groundwater.

II. Match the following:

1. Well irrigation – (a) Water Harvesting System in Ladakh
2. Tank irrigation – (b) Recharging Ground Water Acquifers
3. Zing – (c) Punjab, Haryana and Western Rajasthan
4. Percolation Pit – (d) Exclusively irrigated crops
5. Zaid – (e) Southern India
Answer:
1. Well irrigation – (c) Punjab, Haryana and Western Rajasthan
2.Tank irrigation – (e) Southern India
3. Zing – (a) Water Harvesting System in Ladakh
4. Percolation Pit – (b) Recharging Ground Water Acquifers
5. Zaid – (d) Exclusively irrigated crops

III. Structured Questions:

Question 1.
With reference to conservation of water, answer the following questions:
(a) Why do we need to conserve water?
(b) Suggest five effective measures to conserve water.
(c) What is watershed management? How is it significant in maintaining the water supply in the long run?
Answer:
(a) We need to conserve water for the following reasons:

• The overexploitation of underground water often results in the lowering of water table.
• The loss of vegetation causes drought and reduction of rainfall and of the water table.
• Irrigation utilises more than 90 percent of the totalfresh water.
• The water demand for industrial use will increase more than two times of water demand for domestic use by2025.
• The increase in population with the progress of time results in water scarcity.
• Out water resources like the underground water, river, lakes etc. are polluted and their water can hardly be used without adequate treatement.

(b) Water can be preserved by adoping

• water saving technologies,
• encouraging watershed development,
• rainwater harvesting,
• water recycling and
• preventing the pollution of water.

(c) Watershed Management
Watershed management refers to the efficient management and conservation of both the surface and groundwater resources. It includes prevention of runoff as well as storage and recharge of groundwater by various methods like percolation pits, recharge wells, borewells, dug wells, etc.

The Central Government has started a watershed development project, called ‘Haryali’. It aims at enabling the rural people to conserve water for irrigation, chinking, fisheries and afforestation.

Significance of Watershed Management:
Watersheds are extremely important. Watersheds provide many of us with our drinking water supply, plus recreational opportunities and aesthetic beauty. Unfortunately, the replacement of vegetation by impervious surface like roads, parking lots and rooftops has a negative impact on watersheds. This increases the velocity and amount of runoff flowing into surface waters and causes erosion, turbidity and degraded wildlife habitats.

Not only into surface waters along with it. Forested areas play a very important role in the health of a watershed. The plant cover and leaf litter absorb moisture and help maintain soil structure, while root masses keep soil permeable and stable so moisture can move into it for storage. This is more desirable, because it allows water to be filtered and released slowly into the stream system rather than rapidly running overland.

Question 2.
With reference to rainwater harvesting, answer the following questions:
(a) Briefly state two methods of rainwater harvesting in India.
(b) Mention any two objectives of rainwater harvesting.
Answer:
(a) Two methods of rainwater harvesting in India are:

1. Surface runoff harvesting.
2. Rooftop rainwater harvesting.

(b) Objectives of rainwater harvesting are :

1. To solve the problem of water scarcity.
2. To enhance availability of groundwater at specific place and lime and utilize rainwater for sustainable development.

Question 3.
With reference to irrigation, answer the following questions:
(a) Why is irrigation needed for agricultural development?
(b) What are the conventional methods of irrigation?
(c) What are the drawbacks of conventional methods of irrigation?
Answer:
(a) Irrigation in India has been practised from ancient times. A number of artificial lakes and canals that dot the country are centuries old and some of them have served for more than a thousand years. It is needed for agriculatural development because of the following reasons:
(i) Uncertainly of Rainfall:
The rainfall is highly irregular in place and time. Sometimes monsoon arrives early and at times it comes late. The rainfall is not regular throughout the rainy season leading to water scarcity and withering of crops. Hence, irrigation is the only means to supplement rain water to raise crops.

(ii) Uneven distribution of rainfall:
Most parts of the country receive 80% of the annual rainfall from June to September from the South-west monsoon. Western Ghats and Eastern India receive more than 250 cm of annual rainfall, the northern plains and eastern Peninsula receive between 100 and 200 cm of rainfall, Saurashtra-Kutch region of Gujarat, parts of Punjab and Haryana and western half of Rajashthan lie in the arid zones. The amount of rainfall is low and there is constant scarcity of water. This scarcity has to be met by irrigation.

(iii) Crop rquirements:
Different crops require different quantities of water for their growth.

• Most of the crops do not require water when they are maturing. However, grain crops require more water during the time ear heads are formed.
• High yielding varieties requiring higher quantity of chemical fertilizers which need more moisture which could be supplied only through irrigation.
• Commercial crops like Sugarcane need higher quantity of water as they require frequent watering which could be managed through efficient irrigation system.

(iv) Nature of the Soil:
The water requirement of different crops depends on the natrue of the soil. For example, clayey soils have higher moisture holding capacity and therefore, require less irrigation. On the other hand, the sandy loam soils have less moisture- retentive capacity and need frequent watering. Similarly, the level and lowland areas require less water than the sloping and highland areas.

(v) To Utilise River Water Effectively :
Many rivers in India are not perennial and cany insignificant flows during the rabi season. There is also a wide disparity in the water flow from year to year. The rivers of central and southern India have water for the four months of monsoon rains and remain largely dry during the eight months of the year. Therefore, to utilise the water of these rivers means of irrigation have to be used.

(vi) To Maximise Production :
To obtain maximum production, irrigation is a must. According to agricultural scientists, the production of irrigated crops is more than the unirrigated crops in the same area.

(b) Based on the availability of surface (river) and ground water, relief, soils and climatic conditions, different means of irrigation are utilised in India. The conventional sources of irrigation include tanks, inundation canals and wells. For example, in the crystalline soil areas of Deccan plateau, tanks form the major source of irrigation, whereas the alluvial tracts of the Gangetic and Coastal plans are best suited for canals and well irrigation.

(c) Drawbacks of Conventioanl Methods of Irrigation:
The number of constraints leading to improper utilisation of water. These are the following:
(i) In the conventional system of irrigation a large quantity of water is not properly utilised.

(ii) Crops are usually subjected to cyclic changes of flooding and water stress situations, by providing heavy irrigation at one time and leaving the fields to diy up for about 10 to 15 days. The moisture availability to the crops therefore keeps on changing. This results in poor yields in the crops.

(iii) The fields situated in low areas always get excess water causing prolonged water logging. Thus, crops are subjected to water-logging resulting in poor yields.

(iv) In the fields about 10-15 percent of land is utilised for preparing channels and distributions, etc. which decreases effective area of cultivation.

(v) Extensive areas of land in the arid and semi-arid regions of India have gone out of cultivation due to accumulation of salts. Excessive irrigation and poor water management are the main reasons of water-logging and gradual build up of excessive salts. Progressive build-up of soil salinity has made the soils unsuitable for cultivation.

Question 4.
With reference to well irrigation, answer the following questions:
(a) Why is well irrigation confined mainly to the alluvial plains?
(b) Name the states where well irrigation is practised.
(c) Give two advantages and two disadvantages of well irrigation.
Answer:
(a) Well irrigation is confined mainly to the alluvial plains where
owing to the soft nature of the soil, wells can be easily dug and the yield of crops from the land after irrigation is considerably high. Wells are dug in the middle of the area to be irrigated and at place which is relatively at a high level.

(b) The areas where well irrigation is practised include Uttar Pradesh, Goa, Punjab, Haryana, Bihar, Rajasthan, Gujarat, Maharashtra, Madhya Pradesh, Andhra Pradesh, Karnataka and Tamil Nadu.

(c) Advantages of well irrigation:

• Wells can be dug at a very low cost which is well within the means of poor famers.
• Water can be lifted even from great depths, by the use of pumps and tubewells.

Disadvantages of well irrigation:

• Wells depend on underground water resources whose distribution varies from region to region.
• It is difficult to dig wells or bore tubewells in the hilly regions of the north and story areas of Peninsula.

Question 5.
In the context of canal irrigation, answer the following questions:
(a) In which States of India canal irrigaiton is practised?
(b) Why are perennial canals preferred over inundation canals ?
(c) Give two advantages and two disadvantages of canal irrigation.
Answer:
(a) Canal irrigation is in practice in Uttar Pradesh, Madhya Pradesh, Andhra Pradesh, Rajasthan and Haryana, Jammu and Kashmir, Assam and Tripura. Canals also supply water to a sizeable part of the irrigated area in Bihar, Orissa, Karnataka Tamil Nadu and West Bengal.

(b) Perennial canals are preferred inundation canals as these
(perennial) over canals are taken out from the perennial rivers by constructing barrages to regulate the flow of water. Most of the cause in India belong to this category,

(c) Advantages of Canal Irrigation:

• The rainfall deficiency in some areas is made up canals taken out from the perennial rivers.
• In arid areas like Raj ash than, canals have proved to be boon as a result of which sandy patches are yielding good agricultural harvests.

Disadvantages of Canal Irrigation:
(i) At some places where the perennial unlined canals flow at the ground level and between raised high banks, the water table may reach the surface and make the once cultivable soil completely water logged. Complete saturation of the soil with water may give rise to swamps.

(ii) In the canal irrigation, where the water table is a few feet below the ground, the alkaline salts come to the surface, mix with the soil and make it unproductive.

Question 6.
With reference of tank irrigation, answer the following questions:
(a) How are the farms irrigated using tanks?
(b) Why is tank irrigation preferred over other means irrigation in Peninsular India?
(c) What are the disadvantages of tank irrigation?
Answer:
(a) The tanks can be easily made by means of making dams
in hollow spaces in which rainwater is stored in large quantities for distributing regular supply of water through the channels to the arable lands in the seasons.

(b) Tank irrigation is preferred over other means of irrigation in Peninsular India because of the following reasons :

• In the uneven rocky plateau of Peninsular India, where rainfall is highly seasonal, tank irrigation is useful.
• In the large stretches of the Indian plateau, due to hard rocky terrain, wells and canals are difficult to construct, so only tank irrigation is feasible.
• Tank irrigation is highly significant in stroing the abundant rainwater that would otherwise flow out and go waste.

(c) Disadvantages of Tank Irrigation:

• Tanks get silted up soon and regular desilting is required to make these suitable for irrigation.
• When the monsoons fail these tanks go dry and therefore, are not dependable source of irrigation.
• Most of the tanks are non-perennial and become dry during the winter and summer seasons when water is urgently required for rabi and zaid crops.
• Due to large areal coverage and its shallow depth, huge quantity of stored water is either evaporated or sinks underground without being used in the irrigation.
• Tanks occupy a large fertile area which otherwise could have been utilised for growing crops.
• The lifting of water from the tanks and bringing it to the fields is a strenuous and costly tanks.

ICSE Geography Class 10 Question Bank