CBSE Class 10 Geography - 3 | Water Resources | Full Chapter | NCERT Animation

Summary

This script discusses the importance of water as a renewable resource, highlighting its essential role in life, agriculture, and industry. It addresses the paradox of water scarcity despite its abundance, explaining the limited availability of freshwater and the challenges of uneven distribution, overuse, and pollution. The script also explores solutions like rainwater harvesting and the pros and cons of large dams in managing water resources.

Takeaways

• 🌍 Nearly 75% of the Earth's surface is covered by water, making it one of the most abundant natural resources.
• 🔄 Water is a renewable resource, constantly moving through the hydrological cycle and never truly lost or spent.
• 💧 Freshwater is essential for life, including for drinking, cooking, cleaning, washing, and cultivation, as well as for industrial and economic growth.
• 🏞️ Early human settlements were established near water sources like rivers, highlighting the importance of water for survival and development.
• 🌊 Hydropower is a significant source of electricity worldwide, underlining the role of water in powering industries.
• 🔍 Despite the abundance of water, scarcity issues exist due to the limited availability of freshwater suitable for human and industrial use.
• 🌊 97% of Earth's water is saline, found in seas and oceans, with only 2.5% being freshwater, most of which is locked in ice caps and glaciers.
• 💧 Approximately 0.3% of freshwater is accessible in rivers, lakes, and ponds, which are the primary sources for human and industrial use.
• 🌧️ Rainwater is a vital source of freshwater, but without proper conservation, much of it is lost to the sea or through evaporation and pollution.
• 🇮🇳 India, despite having substantial water resources, ranks 133rd in the world for water availability per person per year, indicating the severity of water scarcity.
• 🚰 Water scarcity is caused by various factors including increased demand, unequal access, overexploitation, and contamination of water resources.

Q & A

What percentage of the Earth's surface is covered by water?

Nearly 75 percent of the Earth's surface is covered by water.

Why is water considered a renewable resource?

Water is considered a renewable resource because it is part of the hydrological cycle, changing forms but never being lost or spent.

Why were early human settlements typically located near rivers or other water sources?

Early human settlements were made along rivers or other water sources because water is vital for cultivation, essential for life, and necessary for daily requirements such as cooking, cleaning, and washing.

What is the primary source of electricity in the world according to the script?

Hydropower is one of the most important sources of electricity in the world.

How much of the Earth's total water is not fit for human and industrial use?

Around 97 percent of the total water available on Earth lies in seas and oceans, which is saline and not fit for human and industrial use.

What percentage of the Earth's total water exists as freshwater that we can use?

Only 2.5 percent of the total water on Earth exists as freshwater that we can use.

Why is water scarcity a problem in different parts of the world despite the abundance of water on Earth?

Water scarcity is a problem because most of the Earth's water is saline and not usable, and only a small fraction of freshwater is accessible and suitable for human and industrial use.

What is the position of India in terms of water availability per person per year according to UNESCO?

According to UNESCO, India is ranked 133rd in the world in terms of water availability per person per year.

What are the main causes of water scarcity in regions with abundant water resources?

The main causes of water scarcity in regions with abundant water resources include an increase in demand, unequal access to water, overexploitation, and contamination of existing water resources.

What is the purpose of dams in managing water resources?

Dams are used to control flooding, divert water into smaller streams for inland navigation, and serve as multi-purpose river projects that offer various benefits such as water storage, irrigation, and hydroelectric power generation.

What are some of the ecological problems caused by the construction of dams?

Some ecological problems caused by the construction of dams include the destruction of natural vegetation and soil, blocking of fish migration, upsetting ecological balance, and potential negative impacts on aquatic species.

Why do some people protest against the construction of large dams in India?

People protest against the construction of large dams in India due to reasons such as mass displacement of people, insufficient compensation, environmental degradation, ecological imbalance, and disputes over water sharing between states.

What is rainwater harvesting and why is it important?

Rainwater harvesting is the process of collecting and storing rainwater during the wet season to meet freshwater requirements in the dry season. It is important because it helps conserve water, recharge groundwater, and utilize one of the purest forms of water available in nature.

What are some traditional methods of rainwater harvesting practiced in India?

Some traditional methods of rainwater harvesting in India include the use of diversion channels in the Himalayas, inundation channels in Bengal, earthen embankments in Rajasthan, and rooftop rainwater harvesting systems in various parts of the country.

How does bamboo drip irrigation work in Meghalaya?

Bamboo drip irrigation in Meghalaya involves using split bamboos to create shallow channels that form a network to divert and carry water from rain-fed springs to farms. The water is allowed to drip near the roots of the plants, providing an efficient irrigation method.

Outlines

00:00

🌊 Water: Our Abundant Yet Scarce Resource

This paragraph highlights the paradox of water abundance and scarcity. Water covers nearly 75% of the Earth's surface and is essential for life, yet only a small fraction is fresh and accessible for human use. The hydrological cycle ensures water's renewability, but geographical distribution and salinity issues limit its availability. Early human settlements were near water sources, and industries rely on it for production and waste management. Despite water's prevalence, scarcity occurs due to the limited sources suitable for human consumption, with most fresh water being locked in ice caps or underground.

05:03

🌍 Causes of Water Scarcity and Its Global Impact

The second paragraph delves into the causes of water scarcity, which include increased demand, unequal access, overexploitation, and contamination of water resources. It emphasizes India's struggle with water scarcity despite its substantial water resources, ranking 133rd in water availability per capita. The growing population, agricultural demands, industrialization, and unequal distribution contribute to scarcity. Additionally, the overuse of groundwater and pollution from various sources exacerbate the problem, threatening health, food security, and economic growth.

10:06

🏞️ The Role and Controversy of Dams in Water Management

This paragraph discusses the multifaceted role of dams in water management, including flood control, inland navigation, and tourism. However, it also addresses the controversies surrounding large dams, such as environmental destruction, displacement of communities, and social inequality. The benefits often accrue to the wealthy, while the poor may not gain much. Ecological imbalances, such as blocking fish migration, and potential man-made disasters from sudden water releases are also highlighted, along with interstate disputes over water sharing.

15:09

🌧️ Rainwater Harvesting: Ancient and Modern Practices

The fourth paragraph explores rainwater harvesting as a solution to water scarcity, an ancient practice still relevant today. It describes various methods used in different regions of India, such as diversion channels in the Himalayas, inundation channels in Bengal, and earthen structures in Rajasthan. The paragraph also explains rooftop rainwater harvesting systems, which collect and filter rainwater for immediate use and groundwater recharge. The importance of this method is underscored by its use even in regions with abundant rainfall, like Meghalaya, to address water scarcity.

20:13

🎍 Bamboo Drip Irrigation: A Unique Harvesting Technique

The final paragraph of the script introduces a unique rainwater harvesting technique used in Meghalaya called bamboo drip irrigation. This method involves using split bamboo to create channels that direct water from rain-fed springs to farms, allowing the water to drip near plant roots. This traditional practice showcases innovative ways to utilize rainwater efficiently, even in regions with high rainfall, emphasizing the importance of local knowledge in water management.

Keywords

💡Hydrological Cycle

The hydrological cycle is the continuous movement of water on, above, and below the surface of the Earth. It involves processes such as evaporation, condensation, precipitation, and runoff. In the video script, it is mentioned that water is a renewable resource that keeps moving in this cycle, changing forms but never being lost or spent. This cycle is crucial for maintaining the availability of fresh water for various uses.

💡Fresh Water

Fresh water is water that is free from significant concentrations of dissolved salts and other total dissolved solids, making it suitable for drinking and other uses. The script highlights that only 2.5 percent of the Earth's total water is fresh water, with a significant portion of it being locked in polar ice caps and glaciers. Fresh water is essential for human consumption, agriculture, and industrial processes.

💡Water Scarcity

Water scarcity refers to the lack of sufficient clean water to meet personal, domestic, and industrial requirements in an area. The script discusses how water scarcity is not just a problem in dry regions but can also occur in areas with abundant water resources due to factors like overexploitation, pollution, and unequal access to water.

💡Groundwater

Groundwater is water that is located beneath the Earth's surface in underground aquifers. The script mentions that nearly 30 percent of the Earth's fresh water is buried in the ground as groundwater. Overexploitation of groundwater through the use of private tube wells and borewells is leading to falling water tables and contributing to water scarcity.

💡Hydropower

Hydropower is a form of renewable energy that is generated by the gravitational potential energy of water. The script notes that hydropower is one of the most important sources of electricity in the world, highlighting its significance in industrial and economic growth.

💡Rainwater Harvesting

Rainwater harvesting is the practice of collecting and storing rainwater for later use, typically during the dry season. The script describes various traditional and modern methods of rainwater harvesting practiced in India, such as rooftop rainwater harvesting and the use of earthen dams, emphasizing its importance in conserving water resources.

💡Multi-Purpose River Projects

Multi-purpose river projects are large-scale infrastructure developments designed to serve multiple purposes, such as irrigation, flood control, power generation, and navigation. The script discusses the benefits and drawbacks of such projects, including the displacement of people, environmental impacts, and disputes over water sharing.

💡Water Pollution

Water pollution refers to the contamination of water bodies with harmful substances, making the water unfit for use. The script mentions that pollution from domestic and industrial waste, as well as the use of chemical fertilizers and pesticides, contributes to water scarcity by making fresh water sources unusable.

💡Ecological Balance

Ecological balance refers to the stable state of an ecosystem, where the numbers and proportions of different organisms are maintained. The script discusses how the construction of dams can disrupt this balance by blocking the migration of fish and other aquatic species, leading to ecological problems.

💡Water Conservation

Water conservation is the responsible use of water resources to prevent waste and ensure sustainability. The script emphasizes the need for water conservation due to the limited nature of fresh water resources and their importance for health, well-being, food security, and economic growth.

💡Inequality in Water Access

Inequality in water access refers to the unequal distribution of water resources, where some groups or regions have better access to water than others. The script highlights how this inequality, particularly between urban and rural areas, contributes to water scarcity and widens social divisions.

Highlights

Nearly 75 percent of the Earth is covered by water, making it one of the most abundant natural resources.

Water is a renewable resource, constantly moving in a hydrological cycle.

Water is essential for life, daily activities, cultivation, and industrial growth.

Early human settlements were typically located near rivers or other water sources.

Hydropower is a significant source of electricity globally.

Only 2.5 percent of Earth's water is freshwater, with most of it locked in polar ice caps and glaciers.

Only 0.3 percent of freshwater is available in rivers, lakes, and ponds for human and industrial use.

India receives around 4 percent of the world's total rainfall, which can be a crucial source of freshwater.

India ranks 133rd in the world in terms of water availability per person per year, indicating water scarcity.

Water scarcity is not only a problem in dry regions but also in areas with abundant water resources due to various factors.

Population growth, industrialization, and unequal water access contribute to water scarcity in India.

Overexploitation of groundwater and pollution of freshwater sources are major causes of water scarcity.

Dams can control flooding, promote inland navigation, and serve as tourist attractions but also have environmental and social impacts.

Large dams can lead to displacement of people, destruction of natural habitats, and ecological imbalances.

Rainwater harvesting is an ancient practice in India, adapted to local conditions for efficient water management.

Different methods of rainwater harvesting are used across India, such as diversion channels, inundation channels, and rooftop systems.

Rainwater is one of the purest forms of water available, and harvesting it can help meet freshwater requirements during dry seasons.

Rooftop rainwater harvesting is widely used in India, with systems that collect, filter, and store rainwater for immediate use and groundwater recharge.

Bamboo drip irrigation is a unique rainwater harvesting technique used in Meghalaya, utilizing bamboo channels to direct water to farmlands.

Transcripts

nearly 75 percent of the earth is

covered by water

water is one of the most abundant

natural resources available to us

one good thing about water is that it is

a renewable resource

it keeps moving in a hydrological cycle

changing from one form to another

but it is never lost or spent

water is essential for life

besides drinking water is essential for

many of our daily requirements

like cooking cleaning

and washing

water is vital for cultivation

this is the reason why all early human

settlements were made along rivers

or other sources of water

water is also essential for industries

and economic growth

hydropower is one of the most important

sources of electricity in the world

industries also require lots of water

for production

cleaning and disposing waste

we all know that 75 percent of the

earth's surface

consists of water

you must be wondering that when water is

such an abundant resource

why is there a scarcity of water in

different parts of the world

the answer lies in the sources of water

available to us

around 97 of the total water available

on the earth

lies in the seas and oceans

this water is aligned and not fit for

human and industrial use

only 2.5 percent of the total water on

the earth

exists as fresh water that we can use

nearly 70 of this fresh water is locked

in the polar ice caps

and glaciers in antarctica

greenland and mountainous regions of the

world

just under 30 lies buried in the earth

as ground water

a small fraction of it is above the

ground or

in the air as water vapor

only around 0.3 percent of the total

fresh water

exists in rivers lakes

and ponds

which are the main sources of water for

human and

industrial use

does we see that only a tiny fraction of

the total water

available on the earth occurs in a form

fit for human and industrial consumption

precipitation all rainfall is another

source of fresh water

india receives around four percent of

the total rainfall

in the world

rain water can be an important source of

fresh water

however in the absence of proper

conservation measures

most of it flows back into the sea

through rivers

or is lost through evaporation and

pollution

india has substantial water resources

still a study by unesco

places india at the 133rd position

in the world in terms of water

availability

per person per year

water scarcity is posing an alarming

threat

in most parts of the world including

india

is water scarcity

the unavailability of sufficient clean

water

to meet personal domestic

and industrial requirements in an area

is called water scarcity

we usually associate the problem of

water scarcity

with dry hot regions like deserts

that receives candy rainfall and have

very few sources of clean surface water

here is a map that shows projected water

scarcity in the world

by the year 2025.

as you can see water scarcity is said to

become

a serious problem in the whole of india

not all regions that face water scarcity

have poor water resources

what leads to water scarcity in regions

that have abundant water resources

an increase in demand unequal access to

water

over exploitation and contamination of

existing water resources

are the main factors that lead to water

scarcity

in regions with abundant water resources

let us study these factors in detail

this brings us to the question what are

the main causes of water scarcity

india has a second highest population in

the world

which is still increasing fast

an increase in population means a

greater demand for fresh water

for personal and domestic use

to feed the increasing population more

and more land is brought

under cultivation

this also increases the demand for water

for irrigation purposes

since independence india has seen a

major industrial revolution

rapid industrialization exerts greater

demand on water resources

since industries use a huge quantity of

water

for production and cleaning

over 70 percent of india's population

still lives in villages

however people living in cities have

better access to water

than people living in most villages

this unequal access to water resources

also leads to water scarcity

groundwater is an important fresh water

resource

however in order to increase their

produce

most farmers today use private tube

wells

to irrigate their fields

this over exploitation of underground

water

is leading to falling water table and

water scarcity

similarly the use of borewells by modern

housing societies

to provide water to their residents is

also

over exploitation of underground water

resources

fresh water sources like rivers and

lakes

are often treated as dumping grounds for

domestic and

industrial waste

this pollutes the fresh water and makes

it unfit for our use

such contamination of fresh water also

contributes to water scarcity

the use of chemical fertilizers and

pesticides

in modern agriculture leads to pollution

of fresh

surface water and groundwater

fresh water is a limited resource

and essential for our health and

well-being

for growing crops to ensure our food

security

and running our industries for economic

growth

thus there is a pressing need to

conserve

and manage our water resources dams are

used to control flooding

in flood prone areas by regulating

the flow of water downstream

one such example is the hirakud dam

in the mahanadi basin in orissa

dams can also be used to divert water

into existing smaller streams to promote

inland navigation

this provides an alternate way of

transport

reducing congestion on roads

several dams are at scenic locations

and have become popular tourist

attractions

and recreation spots

dams are called multi-purpose river

projects

due to the many ways that they offer to

manage our water resources

when multi-purpose river projects have

so many benefits to

offer why do we hear protests

against construction of large dams in

india

a dam creates an enormous reservoir of

water

that submerges vast stretches of the

surrounding area

this leads to the destruction of natural

vegetation

and soil

the submerging of farmlands and

residential areas

leads to mass displacement of people

these people give up their land and

resources

for the nation's greater good but

are usually never compensated enough

dams are used to control flooding in

flood-prone

areas by regulating the flow of water

downstream one such example

is the heracod dam in the mahanadi basin

in orissa

dams can also be used to divert water

into existing smaller streams to promote

inland navigation

this provides an alternate way of

transport

reducing congestion on roads

several dams are at scenic locations and

have become

popular tourist attractions and

recreation spots

dams are called multi-purpose river

projects

due to the many ways that they offer to

manage our water resources

when multi-purpose river projects have

so many benefits to offer

why do we hear protests against

construction of

large dams in india

a dam creates an enormous reservoir of

water

that submerges vast stretches of the

surrounding area

this leads to the destruction of natural

vegetation

and soil

the submerging of farmlands and

residential areas

leads to mass displacement of people

these people give up their land and

resources

for the nation's greater good but

are usually never compensated enough

major benefits of large multi-purpose

projects

go to big landowners and industrialists

while the local poor

landless people have little to gain

this widens the social division between

the rich

and the poor

better irrigation facilities attract

farmers to grow more water intensive

commercial crops

this is leading to over irrigation and

increase in soil salinity

there are ecological problems as well

that can be caused

by the construction of dams

take the example of the cart fish

the carp fish is one of the many species

of fish

that swims hundreds of miles upstream

to return to the waters where it can

breed

dams block the migration of these fish

upsetting the ecological balance and

putting several aquatic species

in danger

there are several examples of sudden

release of

large quantities of water from dams

resulting in large-scale flooding in

plain areas

these are man-made disasters

that not only destroy life and property

but also lead to extensive soil erosion

most indian rivers flow across several

states

large dams obstruct the free flow of

river water

resulting in disputes between different

states

over water sharing and also

over the sharing of costs and benefits

of the project

for example two states in india

andhra pradesh and karnataka which

receive

water from the krishna and godavari

rivers

objected when the government of

maharashtra

tried to divert more water from these

two rivers

for a multi-purpose project at coiner

the direction of water would indeed

reduce the amount of downstream flow to

andhra pradesh

and karnataka

this will adversely affect agriculture

and industry in those states

environmentalists associate large dams

with causing of earthquakes spread of

waterborne diseases and degradation of

soil

constructing a large dam is expensive

and has lasting effects on the

surrounding areas

most of the multi-purpose river projects

in india

so far have not met their desired

objectives

rivers lakes

ponds and wells are our main source

of fresh water

but what is the main source of water

that seeds our rivers

lakes ponds

and wells

the answer is rains

rainwater feeds the sources of our

rivers

rainwater also seeps into the ground

to recharge our underground water

resources

rainwater is one of the purest forms of

water

available in nature

however rainwater is available to us

only for a few months in a year

the process of collecting rainwater

during the wet season

to meet our freshwater requirements in

the dry season

is called rainwater harvesting

rainwater harvesting is practiced in

india

since ancient times

many ingenious techniques were developed

based on local weather conditions

and soil types

let us explore what are the different

methods of rainwater harvesting

practiced in india

in himachal pradesh and jammu in the

western himalayas

rain water and water from glaciers

is harvested using diversion channels

called culls

or gulls

these skulls can be several kilometers

long

and run along steep mountain slopes

water flowing through the coals is

collected in reservoir tanks

in the villages water from these tanks

is used for irrigation as and when

required

farmers in bengal traditionally used

inundation channels

cut through river embankments at times

of floods to irrigate their fields

the flood water that flowed into the

fields also carried silt

a natural fertilizer

in some areas of rajasthan

especially in jaisalmer

earthen embankments

called carbon are built around

farms to collect rainwater during the

rainy season

this saturates the soil for cultivation

in the semi-arid regions of rajasthan

earthen czech dams called

johards are used to collect rain water

flowing down slopes

this water is allowed to percolate into

the ground

rising the level of groundwater

a lot of rainwater falls off the roofs

of our houses

don't you think all this water can be

used

if we can only collect all the raindrops

this is indeed

done in a good number of houses

one of the most widely used methods of

collecting rainwater

is rooftop rainwater harvesting

this method is used in many parts of

india

in a rooftop rainwater harvesting system

pvc pipes are used to collect rainwater

falling on the roof

the water is filtered through sand and

bricks

and stored in tanks for immediate use

excess water is diverted to wells where

it collects

and recharges groundwater

in many parts of rajasthan

rainwater collected through rooftop

harvesting

is collected in large underground

reservoirs

called tankers

the rainwater collected in such tankers

is shielded from sunlight

and thus remains pure for a long time

people use it as drinking water

with the construction of the indira

gandhi canal

water is readily available round the

year in western rajasthan

thus the practice of rooftop rainwater

harvesting

is slowly being abandoned

however some people still practice it

around 200 households in gandatur

a small village in maison karnataka

have also adopted rooftop rainwater

harvesting

at 80 percent collection efficiency

each household can collect 50 000 liters

of rainwater

every year for its use

you would think water harvesting is

carried out

only in areas where water scarcity is

common

due to scanty rainfall however

this is not true

for example chilong

in meghalaya is close to chirapunji

and most syndra the wettest places on

earth

and still faces water scarcity

now almost all households in shillong

use rooftop rainwater harvesting to meet

almost 20 percent of their total

requirement of water

another interesting rainwater harvesting

technique used in meghalaya

for centuries is bamboo drip irrigation

bamboos are split to make shallow

channels

a complex network of such bamboo

channels is used to divert

and carry water from rain-fed springs to

the farms

channel sections in the farm allow the

water to drip

near the roots of the plants

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