4. Rara National Park
Rara National Park is a protected area in the Himalayan region. It was established
in 1976 AD. It covers an area of 106 km² in the Mugu and Jumla districts. It is the
smallest national park of Nepal. The biggest lake of Nepal, i.e. Rara lake lies in
this nationl park. Plants like Rhododendron, Fir, Spruce, Birch, etc.; animals like
Red panda, Musk deer, Himalayan black bear, Leopard, Jackal, Himalayan tahr,
Martin, Wild dog, Langur, Wild boar, Otter, etc. and birds like Coots, Great crested
grebe, Black necked grebe, Gulls, Migrant water fowls, Mallard, etc. are found in
this national park. Coniferous forests and blue pine dominate the park and lake
area respectively. Rara National Park is an excellent habitat for migrating birds
from Saiberia and Mansarobar.
5. Bardiya National Park
Bardiya National Park is a protected area in the Terai region. It was established
in 1988 AD. It occupies an area of 968 km² in Bardiya district. Sal forests and
grasslands cover most area of this national park. Animals like Royal Bengal tiger,
One-horned rhinoceros, Elephant, Swamp deer, Black buck, etc. and reptiles like
Gharial crocodile, Marsh mugger crocodile, etc. are found in this national park.
Similarly, birds like Bengal florican, Lesser florican, Sarus crane, etc. are found in
this national park. Similarly, fresh-water dolphin is commonly seen in the Karnali river.
6. Shey-Phoksundo National Park
Shey-Phoksundo National Park is the largest and only trans-Himalayan park
in Nepal. It covers an area of 3555 km² in the Dolpa and Mugu districts. It was
established in 1984 AD. The park contains the famous Phoksundo lake, the deepest
lake in Nepal. The park contains many gompas and religious sites including
Sanhiemy-aglos mlikpea ,G thhoer aml,o Mstu fsakm doeuesr,, Lwehoipcahr dw, aWs ieldst adbolgis, hMedar mino tth, eM 1o1uths ec ehnatruer, yR. hWesiulds
monkey, Langur monkey, Himalayan tahr, Black bear, Jackal, etc. and birds like
Tibetan partridge, Wood snipe, White-throated tit, Finch, Impeyan pheasant, Cheer
pheasant, Snow cock, etc. are found in this national park.
7. Khaptad National Park
Khaptad National Park is a protected area in the Far-Western. It was established in
1984 AD on the advice of the region’s holy man Khaptad Baba. This national park
covers an area of 225 km² in Bajhang, Bajura, Achham and Doti districts. Plants
like Salla, Khasru, Nigalo, etc. and grasslands add beauty to this national park.
Wild animals like Barking deer, Wild boar, Ghoral, Himalayan black bear, Marten,
Rhesus monkey, Langur monkey, etc. and birds like Impeyan pheasant, Partridge,
Bulbul, Cuckoos and Eagles are found in this national park.
8. Makalu Barun National Park
Makalu Barun National Park is a protected area in the Himalayas established in 1992
AD. It covers an area of 2330 km² in Sankhuwasabha and Solukhumbu districts.
Different types of medicinal herbs, Orchids, wild rose, Gobre sallo, Thingre sallo,
Bhojpatra, Rhododendron, Champ, Phirphire, etc. are found in this national park.
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 243
Similarly, wild animals like Red panda, Snow leopard, Himalayan black bear,
Clouded leopard, Barking deer, Himalayan marmot, Langur monkey, Serous, etc.
and different species of birds including Wren babbler, Ground warbler are found
in this national park.
9. Shivapuri-Nagarjun National Park
Shivapuri-Nagarjun National Park is the ninth national park in Nepal. It was
established in 2002 AD. It is located in the nothern fringe of Kathmandu valley.
It covers an area of 159 km² in the Kathmandu, Nuwakot and Sindhupalchowk
districts. Various species of mushrooms and butterflies are found in this national
park. Wild animals like Leopard, Jungle cat, Golden jackel, Himalayan black bear,
Mongoose, Marten, Barking deer, Wild bear, Monkey, Langur, Pika, Squirrel,
Shrew, etc. and different birds like Eagle Owl, Slender-billed babbler, Flycatcher,
Cuckoo, Golden throated barbet, etc. are found in this national park. This national
park is an important watershed supplying drinking water to Kathmandu.
10. Banke National Park
Banke National Park is the tenth national park of Nepal. It was established in 2010
AD. It covers an area of 550 km² with most parts falling on the churia range. This
national park is located in Banke district in Western Nepal.
Banke National Park is rich in its forest of sal, sissoo and khayar and grasslands.
Different species of birds and wild animals like Tiger, Elephant, Leopard, Wild
Bear, Deer, Langur, etc. and Gharial crocodile are found in this national park.
11. Shukla Phanta National Park
Shukla Phanta National Park is a protected area in the Terai region of the Far
Western Nepal. It was established in 1973 AD. This national park covers an area
of 305 km². It includes open grasslands, forest of sal, sissso and khayar, river
beds and tropical wetlands. Wild animals like Bengal tiger, Leopard, Sloth bear,
Swamp deer, Elephant, Hispid hare, One-horned rhinoceros, etc. and birds like
Bengal florican, Babbler, Eagle, Owl, Hornbill, Wood-pecker, Vulture, Sarus crane,
Flycatcher, Painted stork, etc. are found in this national park. The congregation of
swamp deer (in about 2000 in a group) in the national park’s grassland is the largest
in the world.
12. Parsa National Park
Parsa National Park is a protected area in the inner Terai lowlands of south-central
Nepal. It was established in 1984 AD. This national park covers an area of 637 km²
in Parsa, Makawanpur, Bara and Chitwan districts. This national park contains sal
forest, constituting about 90% of the vegetation and grasslands. Wild animals like
wild elephant, tiger, gaur, wild boar, leopard, deer, etc. and various species of birds are
found in this national park.
B. Wildlife Reserve
A separate reserved area for protection and proper management of endangered
wildlife is called a Wildlife Reserve. In Wildlife Reserves, endangered animals are
244 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
protected by conserving their habitats. Hunting, grazing, cutting down trees, etc.
are not allowed in Wildlife Reserves. There is only one Wildlife Reserve in Nepal
i.e. Koshi Tappu Wildlife Reserve.
Koshi Tappu Wildlife Reserve
Koshi Tappu Wildlife Reserve is a protected area in the eastern Terai of Nepal. It
was established in 1976 AD and designated as Ramsar site in 1987. It covers an area
of 175 km² of wetlands in Sunsari, Saptari and Udayapur districts. This wildlife
reserve is surrounded by Saptakoshi river from the east and west. The main aim of
this reserve is to conserve and promote the wild water buffalo. This wildife reserve
mainly contains forests of sisso and khayar, grasslands and marshy vegetation.
Wild animals like Asian elephant, Spotted deer, Hog deer, Wild pig, Blue bull,
Water buffalo, etc. and various species of birds like Watercock, Indian night jar,
Dusky eagle owl, Black headed cuckoo, Grassbird, Fish eagle, Swamp francolin,
etc. are found in this wildlife reserve.
C. Hunting Reserve
The reserved area established for licensed hunting is called hunting reserve.
Dhorpatan Hunting Reserve is only one hunting reserve in Nepal where licensed
hunting is allowed. This hunting reserve was established in 1987 AD. It covers an
area of 1325 km² in the Dhaulagiri Himal of western Nepal in Rukum, Myagdi and
Baglung districts.
Wild animals like Snow leopard, Musk deer, Blue sheep, Jharal, Nayan, Himalayan
bear, Himalayan tahr, etc. and birds like Koklas pheasant, Cheer pheasant, Impeyan
pheasant, etc. are found. Animals like Blue sheep, Himalayan tahr, Muntjack, Wild
boar and some birds can be hunted in this hunting reserve.
D. Conservation Area
The protected area which is managed according to the plans for conservation of
natural resources, wildlife and their habitat, sustainable development and use of
natural resources is called conservation area. The main goal of a conservation area
is to achieve sustained balance between nature conservation and socio-economic
improvement and to conserve cultural, religious and economic resources of the
local people. In Nepal, six conservation areas have been established in different
parts of the country. They are as follows:
1. Annapurna Conservation Area
2. Manaslu Conservation Area
3. Kanchenjunga Conservation Area
4. Api-Nampa Conservation Area
5. Gauri Shankar Conservation Area
6. Krishnasar Conservation Area
1. Annapurna Conservation Area
Annapurna Conservation Area is Nepal’s largest conservation area. It was
established in 1992 AD. It covers an area of 7629 km² in the Annapurna range of
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 245
the Himalayas across Manang and Lamjung districts. It is managed by the National
Trust for Nature Conservation. This conservation area is rich in biodiversity. The
natural and cultural features of this conservation area have made it the most popular
trekking destination in Nepal. National Trust for Nature Conservation is conducting
various activities like conservation of resources, community development, tourism
management conservation, education and extension for conservation of this area.
2. Kanchenjunga Conservation Area
Kanchenjunga Conservation Area is a protected area in the Himalayas of eastern
Nepal. It was established in 1997 AD. It covers an area of 2035 km² in Taplejung
district and comprises two peaks of Kanchenjunga. In the north, it adjoins Tibet and
in the east it adjoins Sikkim. This conservation area is being developed by WWF
Nepal in partnership with ICIMOD (International Centre for Integrated Mountain
Development).
Kanchenjunga Conservation Area is a habitat of endangered species. It comprises
cultivated lands, forests, pastures, rivers, lakes and glaciers. Plants like Himali larch
Gobre sallo, Thingre sallo, Dhupi sallo and 24 species of Rhododendron are found
in this conservation area. Wild animals like Snow leopard, Musk deer, Himalayan
black bear, Wolf, Nayan, Ghoral, Red panda, etc. and birds like Golden-breasted
fulvetta, Snow cock, Blood pheasant, Red-billed chough, etc. are found in this
conservation area.
3. Manaslu Conservation Area
Manaslu Conservation Area is a protected area located in the Mansiri Himal range
in Gorkha district. It was established in 1998 AD. It covers an area of 1993 km². It is
a classic setting to experience pristine mountain nature and culture. In the north, it
adjoins Tibet and in the west, it adjoins Annapurna Conservation Area. Mt. Manaslu
lies in this conservation area. Wild animals like Himalayan tahr, Nayan, Musk deer,
Snow leopard, etc., different types of birds, reptiles and flowering plants are found
in this conservation area.
4. Api-Nampa Conservation Area
Api-Nampa Conservation Area is a protected area in the Far-Western region of
Nepal. It was established in 2010 AD. It covers an area of 1903 km² encompassing
21 VDCs in Darchula district. The western boundery of this conservation area is
formed by Mahakali river, the northern by the border with Tibet. Adjacent to east
are Baitadi and Bajhang districts. Two peaks Api and Nampa lie in this conservation
area. Various types of forests and grassland plateau are found in this area. High
peak medicinal herbs, different types of mammals like Snow leopard, Himalayan
black bear, Musk deer, Ghoral, Serow, Himalayan tahr, Wolf, Clouded leopard, etc.
and birds like Himalayan monal, Snow cock, Blood pheasant, etc. are found in this
conservation area.
5. Gaurishankar Conservation Area
Gaurishankar Conservation Area is a protected area in the Himalayas of Nepal. It
was established in 2010 AD. It covers an area of 2179 km² in Ramechhap, Dolakha
246 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
and Sindhupalchowk districts. It connects Langtang and Sagarmatha National
Parks. It is the origin of the rivers Khimti, Bhotekoshi, Sunkoshi and Tamakoshi.
This conservation area is rich in biodiversity. Different species of snakes, birds and
mammals like Red panda, Snow leopard, Grey wolf, Musk deer, etc. are found in
this conservation area.
6. Krishnasar Conservation Area
Krishnasar Conservation Area is a protected area in the Terai region of Nepal. It
was established in 2009 AD. It covers an area of 16.95 km² in Bardiya district. The
main goal of this conservation area is to protect Krishnasar, i.e. Black buck.
Activity 2
• Visit a nearby National Park, Wildlife Reserve or a Conservation Area in
your locality.
• Prepare a short report on the basis of your observation.
22.6 Water Resources
The sources of water available on the earth are called water resources. Rain water,
surface water and undergound water are three main sources of water on the
earth. Water resources are very useful for human beings and other organisms. The
majority of human uses require fresh water.
Surface water is the water in a river, lake or wet land. Surface water is naturally
replenished by precipitation (rain) and naturally lost through evaporation. Two-
thirds of the earth is covered by water. In our country, there are various sources of
surface water such as rivers, lakes, wetlands, watersheds, fountains, streams, etc.
Figure 22.2: Water resources
Glaciers are the major sources of water in Nepal. Hydroelectricity can be generated
in a large scale from the rivers of Hilly and Himalayan regions of Nepal.
Importance of Water Resources
Water resources are the sources of water that are very useful. Uses of water include
agricultural, industrial, household, recreational, transport and environmental
activities. The importance of water resources is given below:
(i) Water resources are used to generate hydroelectricity.
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 247
(ii) The hydroelectricity generated with the help of water resources is used to
run industries.
(iii) Water resources are used for irrigating crops.
(iv) Water resources are used for drinking, cleaning, cooking, swimming, bathing,
washing and gardening.
(v) Water resources are used for boating, rafting, rowing, etc.
(vi) Various means of transport like cable car, trolly bus, train, etc. can be operated
by hydroelectricity generated with the help of water resources.
(vii) Water resources are essential to conserve forest, vegetation, wildlife, etc.
(viii) Water is also used in many large scale industrial processes, such as
thermoelectric power production, oil refining, fertilizer production, natural
gas extraction, etc.
(ix) Water resources are important for maintaining environmental balance.
Conservation of Water Resources
Water resources are very useful for human beings and other organisms. Nowadays
water resources are widely used to meet the needs of increasing population.
The unmanaged and over use of water resources brings crisis of water resources
in future. We should not pollute water resources. Water resources should be
conserved to save the habitat of aquatic animals. Water resources are utilized by
human beings to meet their needs. Water resources provide habitat to aquatic
animals. Similarly, water resources help maintain a balance in environment and
natural cycle. Therefore, we should conserve water resources.
Activity 3
• Visit a nearby water resource in your locality.
• Study the importance of that resource.
• Prepare a short report and submit it to your subject teacher.
rafting /ˈrɑːftɪŋ/ - the sport or activity of travelling down a river on a raft
248 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
22.7 Watershed
A watershed is the area of land where all of the water
that is under it or drains off it goes into the same place. It
is also known as a drainage basin. A watershed is an area
of land where surface water from rain and melting snow
or ice converge to a single point at a lower elevation
where the water joins another water body such as river,
lake, wetland, reservoir, etc. A watershed carries water
‘shed’ from the land after rain falls and snow melts. It is
Fig. 22.3: Watershed
a basin like landform defined by highpoint and ridge-
lines that descend into lower elevations and stream valleys. In short, the catchment
area around a source of water is called watershed.
For example, Shivapuri-Nagarjun National Park is a watershed for Kathmandu
valley. The water collected in Shivapuri-Nagarjun area is the main source of water
in Bagmati, Bishnumati rivers and other streams including underground water.
The catchment area around Phewa lake in Pokhara is the watershed for Phewa lake.
The southern belt of Kathmandu valley is watershed of Kulekhani. Indra Sarovar
has been constructed from the watershed of Kulekhani. It is the biggest man-made
lake of Nepal. Koshi, Gandaki and Karnali are the big watersheds of Nepal. There
are many watersheds in our country.
Importance of Watershed
Watershed is a region where all water flowing into it goes to a common outlet or a
reservoir. Watersheds are important as they provide people with drinking water,
water for irrigation, recreation, transportation as well as industrial activities. They
also provide food, water and habitat to plants and animals.
Watersheds give us water for drinking, cooking, cleaning and bathing. Watersheds
are important for wildlife because they provide habitats for both terrestrial and
aquatic animals. They also provide wildlife with clean and fresh drinking water.
Protected watersheds help purify water as it flows across or through land into reservoirs.
Therefore, watersheds are very important for plants, animals and human beings.
Conservation of Watershed
Watersheds provide homes for a wide diversity of plants and animals. Human
beings use watersheds to satisfy their needs. Lakes, streams, rivers, wetlands
provide humans with extensive benefits and support natural life. Nowadays many
watersheds are facing increasing pressure from population growth, industrial
and agricultural development. The demand of water is increasing day by day but
watersheds are being affected adversely by human activities. Therefore, conservation
and promotion of watersheds is very essential. The government should make
policies to involve local people for conserving and restoring watersheds. Various
programmes like afforestation, grass plantation, etc. should be conducted to
conserve watersheds. Conservation of watersheds helps conserve natural resources
and it ultimately helps conserve the natural environment of a country.
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 249
22.8 Wetlands
A wetland is a land area that is saturated with water,
either permanently or seasonally. Wetlands consist
primarily of hydric soil which supports aquatic
plants. So, a wetland is a community composed of
hydric soil and hydrophytes, i.e. aquaitc plants.
` Wetlands are areas of marsh, fen, peat-land or
water, whether natural or artificial, permanent or
Fig. 22.4: Wetland
temporary, with water that is static or flowing, fresh,
brackish or salt, including areas of marine water the depth of which at low tide does
not exceed six metres.
The water found in wetlands can be freshwater, salt water or brackish. Wetlands
play a number of roles in the environment like water purification, flood control,
etc. Wetlands provide home to a wide range of plants and animals. Specifically,
wetlands are characterised as having a water table less than six metres in depth
that supports aquatic plants. They provide a transition between dry land and water
bodies.
Koshi Tappu Wildlife Reserve is the first wetland designated as a Ramsar Site
in December 1987 AD. It consists of freshwater marshes in the flood plain of
the Saptakoshi river. Similarly, Bishajari lake of Chitwan, Jagadishpur lake of
Kapilvastu and Ghodaghodi lake of Kailali districts have been listed in Ramsar
Sites. According to a study conducted by IUCN, there are 163 wetlands in Terai,
164 wetlands in hills and 78 wetlands in the Himalayan region of Nepal. There
are many glaciers, ponds, lakes, swamps, marshes, etc. in our country. Therefore,
Nepal is a rich country in wetland resources.
Importance of Wetlands
Wetlands are very important for human beings, animals and plants. The importance
of wetlands is given below:
(i) Wetlands provide habitat to different organisms.
(ii) Wetlands are excellent places for different types of birds.
(iii) Wetlands help maintain environmental balance.
(iv) Wetlands help in water purification and flood control.
(v) Wetlands provide water for irrigation, recreation, transportation, etc.
(vi) Wetlands are important for fish farming and cultivation of crops.
(vii) Wetlands are important for aqua-tourism.
(viii) Wetlands help to conserve biodiversity.
brackish /ˈbrækɪʃ/ - salty in an unpleasant way
250 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
Conservation of Wetland
Wetland conservation is aimed at protecting and preserving areas where water
exists at or near the earth’s surface such as swamps, marshes, etc. More than three
billion people obtain their basic water needs from freshwater wetlands. The same
number of people rely on rice grown on wetlands. In addition to food, wetlands
supply fibre, fuel and medicinal plants. They also provide valuable ecosystem for
birds, reptiles, fishes, etc. Wetlands help reduce floods, control population, regulate
climate and conserve biodiversity.
Nowadays, various activities of human beings are responsible for destruction
of wetlands. People drain off water to cultivate crops. They dry off wetlands for
settlement and running factories. Similarly, human beings pollute wetlands by
throwing waste materials and industrial chemicals. Those human activities destroy
and pollute the wetlands. Therefore, conservation of wetlands is a very important
task.
We should conserve wetlands to maintain environmental balance, conserve
biodiversity and to develop society. We should not pollute wetlands. We should
not drain off and dry wetlands for cultivation and settlement. We should not throw
industrial by-products into wetlands.
Activity 4
• Visit a wetland nearby your locality. Observe the animals and plants
present there. Identify the major problems of that wetland.
• Prepare a short report on it and submit it to your subject teacher.
22.9 Elements of Environment
We are surrounded by a variety of living and non-living things. If we look around
us, we find soil, water, air, plants, animals, etc. Our surroundings consist of physical
world and biological world. The physical and biological world where we live is
called environment. It is a natural world in which human beings, animals and plants live.
Our environment consists of physical surroundings including climatic factors and
living organisms. The physical surroundings which make up the environment are
air, soil and water. The climatic factors that form a part of environment are sunlight,
temperature, pressure, rainfall, wind, etc.
Similarly, the living organisms that make up the environment are plants, animals
including human beings and micro-organisms.
Environment consists of two components. They are as follows:
(i) Abiotic components
(ii) Biotic components
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 251
Abiotic Components
Abiotic components of an environment are the non-living components like soil,
air, water, sunlight, temperature, rainfall, etc. Abiotic components include physical
environment and climatic factors. The major abiotic components and their role in
the environment is mentioned below:
(i) Air
Air is one of the important abiotic components of environment. It is the mixture of
various gases like nitrogen, oxygen, carbon dioxide, neon, helium, etc. The earth is
surrounded by a layer of air called atmosphere. It contains about 78% nitrogen, 21%
oxygen and 1% other gases.
All living beings need oxygen for breathing. All animals and plants use oxygen
gas during respiration and throw out carbon dioxide gas. Green plants use carbon
dioxide gas during photosynthesis and they release oxygen in the environment.
The air in the atmosphere should be in balanced condition. Imbalance in the
composition of air causes environmental pollution. Various gases released from
industries like carbon dioxide, sulphur dioxide, etc. cause air pollution. The balance
in air is being disturbed by human activities. Deforestation and excessive burning
of fossil fuel are increasing the amount of carbon dioxide in air. Therefore, we
should play a role to reduce air pollution.
(ii) Water
Water is the most abundant abiotic component of an environment. Water molecule is
made of two atoms of hydrogen and one molecule of oxygen. Out of four parts of the
earth, three parts are occupied by water and one part is occupied by land. Water is
found on the surface as well as inside the earth. It is found in stream, river, lake, sea, etc.
Human beings get underground water on the surface of the earth with the help
of tube well, hand pump, etc. Such water is used for drinking, washing, cleaning,
irrigating, etc. All kinds of water available on the earth may not be suitable for
drinking. It is estimated that only 3% of water on the earth is suitable for drinking.
Therefore, pure drinking water has great importance on the earth. All living beings
need water to survive. No organisms can live without water.
(iii) Land
The land is one of the important components of the environment. It is made of rocks
and soil. All living beings including human beings depend on land for survival.
Land is the habitat of most of the plants and animals including human beings. A
majority of plants grow in the soil or land. These plants get water and minerals
from the land. All the animals on land also depend on the soil because they eat
plant food which grows on land. Human beings get crops, fruits, vegetables, etc.
from the land. Therefore, human beings protect and conserve the land in various
ways. This shows the interdependence between human beings and land. Different
types of animals get their food from land. They grow, survive and die on the land.
Hence, there is a close relationship among plants, animals and land.
252 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
Biotic Components
The biotic components of an environment are the living organisms present in that
environment. They include plants, animals and microorganisms. Biotic components
of an environment can be divided into three groups. They are as follows:
(i) Producers (ii) Consumers (iii) Decomposers
(i) Producers
Producers are the green plants which can prepare
their own food by photosynthesis. Only green
Carbon dioxide
plants have the ability to use solar energy. Green Energy from
plants make their own food using water, minerals the sun
and carbon dioxide in the presence of sunlight. Water
Green plants are also called autotrophs.
(ii) Consumers Oxygen
Consumers are the animals which depend on Fig. 22.5
producers directly or indirectly for their food. They cannot prepare their own food.
Some consumers feed only on green plants. They are called primary consumers or
herbivores. For example, deer, cow, sheep, rabbit, goat, etc. Some animals eat other
animals. They are called secondary consumers. For example, cat, fox, fish, dog, etc.
Some consumers feed on primary and secondary consumers. These animals are
called tertiary consumers. For example, vulture, crocodile, lion, etc. Some animals
feed only on flesh of other animals. These animals are called carnivores. For
example, tiger, lion, eagle, etc. Some consumers feed on both plants and animals.
These animals are called omnivores. For example, dog, cat, man, crow, bear, etc.
Grass Frog
Grasshopper
Snake Hawk
Figure 22.6: Biotic components
consumers /kənˈsjuːmə/ - the animals that depend on producers for food
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(iii) Decomposers
Decomposers are the saprophytes which act on dead and decaying bodies. Bacteria
and fungi are called decomposers as they break down the remains of dead plants
and animals into simple substances. Decomposers release nutrients from dead and
decaying organisms into the environment. These nutrients are reused by plants for
their growth. Thus, decomposers help in the recycling of nutrients.
Activity 5
• Visit a place nearby your school.
• Observe any five abiotic components and any five biotic components.
• Classify the biotic components in terms of producers and consumers.
22.10 Man and Environment
Human beings live in various parts of the world. Human beings modify natural
resources according to their desires and needs. We obtain food and habitat from
the land. Similarly, we get timber, firewood, fodder, medicines, etc. from the forest.
Human beings use water resources to get water for drinking, cooking, bathing,
washing, etc. They use water resources for irrigation, recreation, transportation as
well as industrial purpose. The waste materials produced from industries reach the
environment. The amount of harmful gases like carbon dioxide, carbon monoxide,
sulphur dioxide, etc. is increasing in the atmosphere. Similarly, land and water are
also being polluted by human activities. The landforms are being changed due to
human activities. Human beings perform various activities on the environment.
Therefore, there is a close relationship between human beings and environment.
Human Impact on the Environment
Human beings can modify physical and biological environment to meet their
needs. Various human activities bring a great change in the environment.
Human activities are responsible for polluting air, water and soil. Human beings
clear forests for settlement and agriculture. They use insecticides and chemical
fertilizers. They are destroying water resources. These activities create imbalance
in the environment. Imbalance in environment invites natural disasters like flood,
landslide, etc. Unmanaged urbanization and development works are also degrading
the environment. Natural resources are being destroyed, water resources are being
dried and environment is being polluted by human activities. Therefore, human
activities are solely responsible for bringing imbalance in the environment and
environmental degradation.
Effects of Environmental Degradation on Human Life
Degraded environment adversely affects human beings, plants and other organisms
that live in the environment. The effects on human beings due to environmental
degradation are as follows:
254 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
(i) Human beings face scarcity of water.
(ii) Human beings suffer from various diseases.
(iii) Human beings do not get suitable climate and environment.
(iv) Human beings face crisis of food due to loss in crop production.
(v) Number of wildlife decreases and some of them become extinct.
(vi) Human beings face various calamities like flood, landslide, drought, global
warming, acid rain, etc.
(vii) Human beings do not get fresh air to breathe and pure water to drink.
(viii) Ecosystem gets imbalanced which affects humans adversely.
Role of Humans to Conserve Environment
Healthy environment is the major basis of existence of human beings on the earth.
Human activities are responsible for environmental degradation. So it is the duty
of human beings to conserve environment. Human beings should conserve the
fundamental elements of environment such as air, water, soil, vegetation, wildlife,
etc. We should reduce the amount of harmful gases released from industries and
vehicles. We should not throw waste materials and sewage to the sources of water.
We should reduce the use of insecticides, pesticides and chemical fertilizers to
reduce environmental pollution. We should dispose waste materials in scientific
ways. We should encourage afforestation and discourage deforestation. We should
conserve wildlife and natural resources. Construction of roads, buildings and
bridges should be done scientifically on the basis of bioengineering. We should
control poaching of wild animals. Conservation of the elements of environment
helps maintain balance in environment. Therefore, there is a great role of human
beings to maintain environmental balance.
Activity 6
• Study the natural resources in your surroundings. Classify them in terms
of renewable and non-renewable resources.
calamity /kəˈlæməti/ - an event that causes great damage to people’s lives
drought /draʊt/ - a long period of time when there is little or no rain
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 255
Summary
• The resources such as water, minerals, forests, fertile land, sunlight, wind, etc.
that occur in nature are called natural resources.
• The resources having never ending supply and do not get depleted after use
are called perpetual resources.
• The natural resources that never deplete while being used and can be produced
again and again are called renewable resources.
• The resources that get depleted after their use and cannot be obtained again
and again are called non-renewable resources.
• The conservation of natural resources is a fundamental problem in today’s
world.
• Protected areas are the reserved areas like national parks, wildlife reserves,
conservation areas, etc. established for protection and promotion of wildlife,
vegetation and natural environment.
• A national park is an area set aside for the conservation and management of
natural environment including wild animals, plants and landscapes together
with their utilization.
• A separate reserved area for protection and proper management of endangered
wildlife is called a Wildlife Reserve.
• The reserved area established for licensed hunting is called hunting reserve.
• The protected area which is managed according to the plans for conservation
of natural resources, wildlife and their habitat, sustainable development and
use of natural resources is called conservation area.
• A watershed is an area of land where surface water from rain and melting
snow or ice converge to a single point at a lower elevation where the water
joins another water body such as river, lake, wetland, reservoir, etc.
• The physical and biological world where we live is called environment.
• Human beings can modify physical and biological environment to meet their
needs.
• Human activities are solely responsible for bringing imbalance in the
environment and environmental degradation.
• Human beings should conserve the fundamental elements of environment
such as air, water, soil, vegetation, wildlife, etc.
• We should reduce the use of insecticides, pesticides and chemical fertilizers to
reduce environmental pollution.
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Exercise
1 Choose the best answer from the given alternatives.
a. On the basis of characteristics, natural resources are of
(i) two types (ii) three types
(iii) four types (iv) five types
b. Which of the following energy sources are perpetual sources of energy?
(i) fresh air and vegetation (ii) minerals and coal
(iii) sunlight and wind (iv) wildlife and petrol
c. How many national parks have been established in Nepal?
(i) eight (ii) nine
(iii) seven (iv) ten
d. Which of the following wildlife reserves is located in Kanchanpur district?
(i) Shukla Phanta Wildlife Reserve
(ii) Parsa Wildlife Reserve
(iii) Koshi Tappu Wildlife Reserve
e. Which of the following is the first national park of Nepal?
(i) Shivapuri–Nagarjun National Park
(ii) Chitawan National Park
(iii) Bardiya National Park
(iv) Sagarmatha National Park
f. Which of the following are primary consumers?
(i) Green plants (ii) Herbivores
(iii) Carnivores (iv) Omnivores
2 Fill in the blanks with appropriate words.
a. The resources that are found in nature are called ......................
b. There are ...................... wildlife reserves in Nepal.
c. The only one hunting reserve of Nepal is ......................
d. Api-Nampa Conservation Area is located in ...................... district.
e. The green plants that can prepare their own food are called ......................
f. Bacteria and fungi are called ......................
g. A wetland is a community composed up hydric soil and ......................
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 257
3 Answer the following questions.
a. What are natural resources? Name the three types of natural resources?
b. What are perpetual natural resources? Give any two examples.
c. Why are natural resources important? Give any three reasons.
d. What is meant by protected areas? Give any two examples.
e. What are national parks? Name the ten national parks of Nepal.
f. What are wildlife reserves? Name the wildlife reserves of Nepal.
g. What is a hunting reserve? Name the hunting reserve of Nepal.
h. What are conservation areas? Name the conservation areas of Nepal.
i. Where is Gaurishankar Conservation Area located?
4 What are water resources? Describe the importance of water resources in brief.
5 Why should we conserve water resources? Describe.
6 What are watersheds? Give any three examples.
7 Describe the importance of watersheds in brief.
8 What are wetlands? Describe the importance of wetlands in brief.
9 What are biotic components? Explain their types in brief.
10 Describe the role of human beings in environmental balance.
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Unit Estimated teaching periods: Th Pr
14 3
23
Volcano
Environmental Degradation
and Its Conservation
Objectives
After completing the study of this unit, students will be able to :
• explain the causes of deforestation.
• describe the degradation of natural resources and explain its effects on the
environment.
• explain the effects of natural disasters (earthquake and volcano eruption) and describe
preventive measures of those disasters.
• demonstrate knowledge regarding three aspects of environmental sanitation: reduce,
reuse and recycle and apply them.
• explain the local and national efforts on environmental conservation.
Course of Study
• Introduction to environmental degradation and conservation
• Deforestation and its effects
• Urbanization and industrialization
• Degradation of natural resources and its effects
• Natural disasters (earthquake and volcano)
• Environmental sanitation
• Local efforts on environmental conservation
• Organizations and agencies involved in environmental conservation
Points to be Focused / Questions to be Discussed
• What is environmental degradation?
• What is deforestation? What are its causes and effects?
• What are effects of degradation of natural resources?
• What are the effects and preventive measures of earthquake and volcano?
• What is environmental sanitation?
• What is the role of various organizations and agencies in conservation of environment?
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 259
23.1 Introduction
The physical and biological world around us is called environment. Various aspects
like natural, biological, social and cultural are the major aspects of environment.
Various human activities and natural disasters change or disturb the condition
of those aspects of the environment, which is called environmental degradation.
The deterioration of the environment through depletion of resources such as air,
water and soil, the destruction of ecosystem and the extinction of wildlife is called
environmental degradation.
Environmental degradation is the damage or disturbance in any aspect of the
environment due to human activities and natural disasters. The United Nations
International Strategy for Disaster Reduction defines environmental degradation
as “The reduction of the capacity of the environment to meet social and ecological
objectives and needs.” Environmental degradation is of many types. When natural
habitats are destroyed and natural resources are depleted, the environment is
degraded. Various factors are responsible for environmental degradation. The
major causes of environmental degradation are human causes and natural causes.
The degradation of environment due to natural disasters such as earthquake, volcano
eruption, etc. is called natural cause. Human beings use natural resources to satisfy
their needs. Various human activities deplete the natural resources. Deforestation,
urbanization, industrialization, etc. are the human activities that degrade the
environment. These are the human cause of environmental degradation. In this
unit, you will study the human causes of environmental degradation.
23.2 Deforestation
Forest is one of the important natural
resources. Human beings obtain
firewood, timber, fodder, grass, etc. from
the forest. Human beings clear forests for
settlement, farming and urbanization.
About 2000 trees are cut down in the
rain forests per minute and about half
of the world’s tropical forest has been
cleared. Deforestation is the permanent
destruction of forests or clearing of trees Fig. 23.1: Deforestation
in order to make the land available for
other uses. Deforestation is considered to be one of the contributing factors to
climate change. Deforestation occurs throughout the world, however, tropical rain
forests are particularly targeted.
Causes of Deforestation
Deforestation is typically done to make more land available for housing and
urbanization, timber, cash crops and cattle ranching (breeding). The major causes
degradation /ˌdeɡrəˈdeɪʃn/ - the process of sth being damaged or made worse
deplete /dɪˈpliːt/ - to reduce sth by a large amount so that there is not enough left
260 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
of deforestation are given below:
(i) Deforestation is done for housing and urbanization.
(ii) Deforestation is done to get land for farming and growing cash crops.
(iii) Deforestation is done to get timber, firewood, etc.
(iv) Deforestation occurs due to forest fire or wild fire.
(v) Deforestation occurs due to natural disasters like flood, landslide and soil erosion.
(vi) Deforestation occurs due to increase in construction works.
(vii) Deforestation occurs due to migration of human beings.
(viii) Deforestation occurs due to overgrazing.
(ix) Deforestation occurs due to industrialization.
Effects of Deforestation
Forests play a great role to maintain environmental balance. Forests regulate water
cycle, carbon cycle, oxygen cycle, etc. in nature. Deforestation leads to imbalance in
environment. Deforestation contributes to global climate change. The major effects
of deforestation are given below:
(i) Wild animals lose their habitats which can lead to extinction of wildlife.
(ii) Deforestation leads to global climate change which affects plants and animals.
(iii) Deforestation affects water cycle, which affects agricultural pattern.
(iv) Deforestation increases the occurrence of natural disasters like flood,
landslide, soil erosion, etc.
(v) Deforestation leads to loss of timber, firewood and medicinal plants.
(vi) Deforestation increases the amount of carbon dioxide and decreases the
amount of oxygen in air.
(vii) Deforestation affects the fertility of soil.
(viii) Deforestation leads to drying of water resources and degrades water quality.
All of these factors have adverse effect on environment. Therefore, we should
conserve forest resources by wise and economic use of forest, controlling forest fire
and reducing overgrazing and encouraging afforestation.
23.3 Urbanization
Human beings build big cities
on land. They transform villages
into towns and towns into cities.
It affects forests, water resources,
fertile land, and open places.
As a result, environment gets
degraded.
Fig. 23.2
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 261
23.4 Industrialization
Human beings run various factories and industries
on land. We need raw materials to run industries
which are obtained from environment. We use
minerals, firewood, coal, etc. in most the industries.
More industries require more raw materials and
fuel. So overuse of raw materials and fuel degrades
the environment. Most industries release smoke,
harmful gases, harmful chemicals and waste
materials. These substances cause environmental Fig. 23.3
pollution and hence environmental degradation.
Therefore, we should adopt techniques to minimize environmental degradation
while running factories and industries.
Activity 1
• Observe some human activities in your surroundings. Are these activities
causing environmental degradation?
• Prepare a short report on the basis of your observation.
23.5 Degradation of Natural Resources and Its Effects
Various resources like air, water, soil, minerals, fossil fuel, vegetation, wildlife,
etc. are natural resources. Human beings depend on those resources for various
purposes. Human beings utilize the natural resources to fulfil their needs. Increasing
population is creating pressure on the natural resources. Therefore, natural
resources are being depleted day by day. The depletion and over exploitation
of natural resources results in environmental degradation. Living beings cannot
survive in degraded environment and they may become extinct. Therefore, various
programmes should be launched to protect natural resources.
Vegetation
The forests, fruit trees, vegetables, grasses, herbs, etc. around us are important
natural resources. We get firewood, timber, fodder, fruits, medicines from those
resources. Human beings use grasslands and forests for grazing cattle. Over use of
forests and grasslands results in the depletion of vegetation. The effects of depletion
of vegetation on the environment are given below:
(i) The amount of oxygen in atmosphere decreases.
(ii) The habitats of wildlife will be lost.
(iii) Valuable vegetation and medicinal herbs will become extinct.
(iv) Occurrence of natural disasters like flood, landslide, soil erosion increases.
(v) Wildlife will become extinct.
(vi) Food cycle will get destroyed.
(vii) Environment will be imbalanced.
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Animals and Birds
Animals and birds are also important natural resources. Human beings also
depend on animals and birds for various things. Human beings depend on cow,
buffalo, goat, sheep, etc. for milk. They use horse, donkey, sheep, buffalo, ox, etc.
for transportation. They use goat, sheep, buffalo, rabbit, chicken, etc. for meat.
Human beings get wool from sheep, rabbit, etc. Different types of birds and animals
add beauty to nature. Animals and birds lose their food sources and habitats due
to deforestation. The number of herbivores and carnivores is decreasing due to
deforestation. Some species of animals and birds have become extinct. It affects
food cycle and leads to environmental imbalance. For example, the number of
herbivores decreases due to depletion of grasses and vegetation and the number of
carnivores decreases due to decrease in the number of herbivores. In this way, the
species of birds and animals may be extinct due to lack of food and habitat.
Activity 2
• Study the condition of forest in your locality. What is the condition of the
forest and wild animals at present? Prepare a short report and submit it to
your subject teacher.
Water Resources
Water resources are very important natural resources. Animals and plants cannot
survive without water. Human beings use water for drinking, irrigation, generating
hydroelectricity, fish farming, industrial uses, etc. The sources of water are being
polluted because of human activities. Human beings throw waste materials
in the river. Many water bodies near urban areas are highly polluted. Human
beings dump garbage in the water resources. They dump harmful chemicals from
industries, hospitals, etc. in the water bodies. It adversely affects aquatic animals as
well as human beings. Water pollution leads to extinction of aquatic animals. The
sources of water are depleted due to unmanaged use of water resources. It affects
water cycle. Human beings do not get pure and clean water. Human beings and
other animals suffer from various diseases. Therefore, we should conserve water
resources and contribute to reduce water pollution.
Fuel
Solar energy is the main source of energy for the earth. Green plants use solar energy
to prepare their own food during photosynthesis. Animals depend on plants for
getting food. Human beings get firewood from forests. Petroleum products like
petrol, diesel, coal, etc. are formed under the crust from the dead bodies of plants
and animals. Petrol, diesel, coal, kerosene, firewood are used as fuel. Petroleum
products are non-renewable energy sources. Nowadays, these sources are used
widely. These sources of energy have limited stock in nature. So, overuse of those
energy sources causes energy crisis. Human beings are clearing forests for firewood.
It invites natural disasters like flood, landslide, soil erosion, etc.
garbage /ˈɡɑːbɪdʒ/ - waste food, paper, etc that we throw away
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 263
Air
Air is the basis of life for all living beings. Living beings breathe in oxygen and breathe
out carbon dioxide. All living beings need fresh air to breathe. Smoke released from
vehicles and industries, dust particles, etc. get mixed in air and pollute it. Various
human activities are responsible for air pollution. Polluted air adversely affects
human beings, animals and plants. Human beings suffer from respiratory diseases.
Harmful gases like sulphur dioxide, nitrous oxide, etc. released from industries
cause acid rain. Acid rain affects crops, historical monuments, inscriptions, metals,
etc. Polluted air leads to imbalance in environment.
Land
Land is the habitat of different organisms. Land is made of rocks and soil. Land
provides food and habitat to plants and animals. Human beings get food from
plants and animals that live on land. Various human activities are responsible for
soil pollution. Polluted soil affects human beings, plants and animals.
Minerals
Minerals are the metals, non-metals and their compounds found inside the earth’s
crust. Minerals are the valuable natural resources. These are non-renewable
resources. Human beings use minerals for various purposes. Overuse of those
resources may lead to crisis of minerals in future. We should conserve minerals
for future generations. Therefore, we should use mineral resources wisely and
judiciously so that they may last as long as possible.
23.6 Natural Disasters
Various events like earthquake, volcano, landslide, flood, etc. occur in nature.
These events are called natural disasters. Every year many lives and property are
damaged in Nepal due to natural disasters like flood, landslide, soil erosion, etc. In
this unit, we will discuss natural disasters like earthquake and volcano with their
causes, effects and safety measures.
Earthquake
The sudden shaking of the earth’s surface is called
earthquake. It occurs due to sudden release of
energy in the earth’s surface. An earthquake is the
vibration of the earth’s surface. The vibration may
be up and down or left and right.
Nepal is situated in the active earthquake region.
In Nepal, earthquake has occurred several times. In
1990 B.S., a devastating earthquake occurred with a
magnitude of 8.3 Richter scale. It killed 8519 people Fig. 23.4: Earthquake
and destroyed thousands of houses and buildings. Similarly, the earthquake that
occurred in 2045 B.S. killed 721 people and damaged 65,000 houses and buildings.
Its magnitude was 6.6 Richter scale. On 12 Baisakh 2072, at 11:56 AM local time,
devastating earthquake of about 7.6 magnitude struck Nepal, with epicentre in
Barpak of Gorkha district. This caused thousands of death and injuries leaving
264 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
millions of people displaced from rural hilly areas and Kathmandu Valley. Many
after shocks followed and majority of population remained outside the house
for at least for 4-5 nights. The districts of Western and Central region including
Kathmandu Valley were highly affected by the earthquake. The earthquake killed
more than 8,500 people, injured 16033 and damaged 416,359 houses. Several villages
in rural areas, public and historic buildings of Kathmandu Valley collapsed or were
damaged due to the earthquake.
Causes of Earthquake
(i) Earthquake occurs due to the movement of tectonic plates present beneath
the earth’s surface.
(ii) Earthquake occurs due to contraction and relaxation of rocks beneath the
earth’s crust.
(iii) Earthquake occurs due to volcano eruption.
(iv) Earthquake also occurs due to explosions during the extraction of minerals.
Effects of Earthquake
(i) Earthquake may bring changes on the earth’s surface. Plain surfaces may
change into hills and mountains. Similarly, hills and mountains may change
into plain surface.
(ii) Earthquake may destroy water resources.
(iii) Earthquake destroys houses, buildings, bridges, roads, etc.
(iv) A large number of people may be killed in earthquake.
(v) Earthquake may cause flood and landslide.
(vi) Earthquake destroys electric cables, communication lines, water pipes,
sewage pipes, canals, etc.
(vii) Earthquake under the ocean may cause tsunami.
Preventive and Safety Measures of Earthquake
(i) We should construct houses, buildings, bridges, etc. by following earthquake
resistant technology.
(ii) The public should be made aware of the ways of self–protection against
earthquake.
(iii) During earthquake, we should crouch under the table or strong support and
protect head from injury.
(iv) We should not run here and there during an earthquake.
(v) We should stay away from weak walls, electric cables and tall buildings.
(vi) We should turn off switches, gas stoves and water supply as soon as possible.
(vii) We should stay in a safe place with patience until shaking stops and listen to
the broadcast from radio by the government.
(viii) We should keep necessary things like torchlight, radio, first aid box, dry food,
drinking water, etc. for emergency use.
(ix) We should help disabled people and not stay in closed and narrow streets
during an earthquake.
tsunami /tsuːˈnɑːmi/ - an extremely large wave in the sea caused by an earthquake
sewage /ˈsuːɪdʒ/ - used water and waste substances produced by human bodies that
are carried away through pipes
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 265
Volcano
A volcano is a place on the earth’s surface where molten Fig. 23.5: Volcano
rocks, gases and debris erupt through the earth’s crust.
The mantle of the earth is very hot. The metals and
rocks in the mantle are found in molten state. This
molten mass is called magma. When magma erupts
through the weak parts of the crust it is called lava.
Lava can be thick and slow moving. Rocks also come
from volcanoes including ash, bits of fragmented lava
and pumice (light-weight rock with air bubbles).
Causes of Volcano
(i) Volcano eruptions are caused mainly by shifting of tectonic plates. When
these plates shift, cracks or fissures are formed in the earth’s crust. The molten
mass inside the earth erupts through these cracks or fissures.
(ii) Volcanoes form when hot magma from the earth’s mantle flows through
cracks in the rocks to the surface of the earth. When water on the surface of
the earth enters the mantle through these cracks, the water evaporates and
creates pressure. It causes the magma to flow up through these cracks which
is called volcano eruption.
Effects of Volcano
(i) Volcano brings changes in the structure of the earth’s surface.
(ii) It covers forests, fertile lands, crops, etc.
(iii) It destroys man-made physical infrastructures and other animals.
(iv) It kills people on its way and destroys property.
(v) Volcanic ash and gases cause air pollution.
(vi) Volcano eruption near the sea creates tsunami which destroys life and property.
Activity 3
• Visit a place in your locality which is affected by landslide, flood or soil
erosion. Observe the situation around it and find out the causes and effects
of that disaster. Prepare a report and submit it to your subject teacher.
23.7 Environmental Sanitation
Environmental sanitation is the creation of clean and hygienic environment around
us which is essential for maintaining good health. We should control all those
factors which pollute the environment. The proper management and disposal
of waste materials is an important factor to maintain environmental sanitation.
The various waste materials that pollute environment include sewage, animal
wastes, plastics, agricultural wastes, industrial wastes, insecticides, pesticides, etc.
These waste materials should be treated properly to make them harmless before
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their disposal.
We should know the proper method of waste disposal. To maintain environmental
sanitation in local level, the most effective technique is the “Three ‘R’s” – Reduce,
Reuse and Recycle.
Reduce
We should reduce the number of things that we use as far as possible. We should
not use more materials than we need. It helps to produce less waste.
Reuse
Some materials like plastic bags, bottles, tin cans, cartons, etc. can be used again and
again. Old bags, tin cans, cartons, etc. can be reused to store things. Similarly, old
books can be reused by other students. This practice helps to conserve the sources
and keep the environment clean.
Recycle
Some waste materials like plastic wastes, metal pieces,
glasses, papers, etc. can be recycled in factories to produce
new things. By doing so, waste materials can be used again
and again. It also helps to keep the environment clean and
conserve raw material resources in nature.
Thus, we can reduce wastes, save environment and save Fig. 23.6
money too by adopting the Three ‘R’s.
Activity 4
• Prepare a list of the materials at your home that can be:
(i) Reduced (ii) Reused (iii) Recycled
• Discuss in your class how these materials can be reduced, reused and
recycled.
23.8 Local Efforts on Environmental Conservation
We can conserve and promote environment by proper management of environmental
components. Human being is the major consumer of environmental components.
Therefore, it is the major duty of human being to conserve environment. We should
generate public awareness, plant trees, conserve forests and cultural resources to
conserve environment.
We should pay attention to the following things to conserve environment in local level.
1. Public awareness
The involvement of local people is essential to conserve the environment. We
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 267
should conduct various programmes to generate public awareness to conserve
environment.
2. Integrated conservation programme
The structure of land is disturbed while constructing road, bridge, canal, drainage,
etc. These activities change the form of land, forest, river, etc. Therefore, we should
conduct integrated programme to conserve environment while doing construction
works.
3. Public participation
We should involve as many people as possible to conserve environment. People’s
participation increases responsibility of local people to conserve environment and
the conservation of environment also becomes meaningful.
4. Afforestation and conservation of forest
Deforestation is a major environmental problem. We should conduct afforestation
programmes in slopes, barren fields, etc. Plantation in slopes and landslide affected
areas prevents soil erosion. Forests are important natural resources. It is our duty
to conserve forests.
5. Environment sanitation
Increasing population is the major cause of environmental pollution. Increasing
population requires more natural resources. Increasing means of transportation
increases air pollution. We should perform following activities to conserve
environment by environmental sanitation.
(i) We should keep our surroundings clean.
(ii) We should manage the household wastes properly.
(iii) We should conserve water resources.
(iv) We should use gobar gas (bio-gas) and solar energy for fuel.
(v) We should conduct sanitation programmes in our locality.
6. Conservation and promotion of cultural resources
Nepal is rich in cultural resources. Various human activities bring changes in the
forms of those resources. Therefore, we should make policies to conserve and
promote cultural resources.
In this way, we can contribute a lot to conserve environment by conducting various
activities and programmes in our locality.
Activity 5
• What type of activities are being conducted in your locality to conserve
environment? Prepare a short report and submit it to your subject teacher.
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23.9 Organization and Agencies Involved in Environmental
Conservation
Environmental pollution and degradation is a global problem. It is the responsibility
of human beings to conserve environment. Various national and international
organizations and agencies are involved to conserve environment. The organizations
and agencies involved in conservation and promotion of environment in Nepal are
given below:
A. Governmental agencies
In Nepal, governmental agencies are playing a significant role to conserve
environment. In this unit, we will discuss the following governmental agencies that
are working to conserve and manage the environment.
1. Ministry of Science, Technology and Environment
2. Ministry of Forests and Soil Conservation
1. Ministry of Science, Technology and Environment
Ministry of Science, Technology and Environment has been established to solve and
manage environmental problems. It makes policies, rules, acts, plans and programs
related to solving and managing environmental problems and implements them.
The major goals of this ministry are as follows:
(i) To conserve natural and cultural environment
(ii) To conserve air, water and soil
(iii) To develop and promote traditional indigenous technology
(iv) To conduct research in the field of science, technology and environment
(v) To create appropriate opportunity for the people working in the field of
science, technology and environment to encourage them
Major Functions
(i) This ministry makes environment-friendly policies, plans, acts, laws and
implements them.
(ii) It monitors and evaluates various development works, constructions and industries.
(iii) It makes pollution control directives and implements them.
(iv) It develops human resources in the field of environment through study,
research, training, meeting, seminar, etc.
(v) It co-ordinates among national, international and non-governmental
organizations.
(vi) It generates awareness regarding environment through various media such
as radio, television, newspapers, etc. It also disseminates information through
seminars, meetings, leaflets, posters, pamphlets, etc.
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2. Ministry of Forests and Soil Conservation
Ministry of Forests and Soil Conservation has been established to study, research,
conserve and promote forest, soil, water resources and biodiversity of Nepal. The
major aims of this ministry are as follows:
(i) To conserve and manage forests
(ii) To conserve forests, plants and wild animals
(iii) To conserve and utilize medicinal herbs and forest products
(iv) To conserve watersheds
(v) To conserve natural ecosystems
Major Functions
(i) This ministry frames policies, rules, acts, laws, directives, etc. and implements
them.
(ii) It makes plans on the basis of national policy of forest conservation and
promotion and implements them.
(iii) It monitors, evaluates and reviews the programmes related to conservation.
(iv) It conducts various conservation programs by co-ordinating with various
national, international and non-governmental organizations.
(v) It generates awareness regarding the conservation of soil through various
media such as radio, television, newspapers, posters, seminars, meetings, etc.
Department of Forests has been established under the Ministry of Forests and
Soil Conservation. This department conserves, promotes and manages the total
forest areas of Nepal. It makes policies and rules regarding the conservation and
utilization of forests. It also implements the rules and regulations. This department
has divided forests as government forests and community forests. This department
conserves medicinal plants and forest products. It emphasizes on the utilization of
forest products by conserving them.
Similarly, Department of Soil and Water Conservation plays a role to conserve
soil and water resources. It works for minimizing natural disasters such as floods,
landslides, soil erosion, etc. Similarly, Department of National Parks and Wildlife
Conservation plays a role to conserve and manage national parks, wildlife reserves
and conservation areas. It conducts various programmes to conserve biodiversity
and protect various wild animals. It helps conserve natural ecosystem in the earth.
It this way, Ministry of Science, Technology and Environment and Ministry of
Forests and Soil Conservation have been playing a significant role in the field of
environment conservation, promotion and management.
B. Non-Governmental Organizations
Following non-governmental organizations are playing important role to conserve
and promote environment in Nepal.
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1. World Wide Fund for Nature (WWF)
The World Wide Fund for Nature (WWF) formerly named as
World Wildlife Fund, is an international non-governmental
organization. It is working on issues regarding the conservation,
research and restoration of the environment. It was established on
April 29, 1961 in Morges, Switzerland.
WWF is the world’s largest independent conservation organization with over
5 million supporters worldwide, working in more than 100 countries including
Nepal. WWF opened its office in 1993 in Nepal and started working here.
The main mission of WWF is to stop the degradation of the planet’s natural
environment and to build a future in which humans live in harmony with nature, by
• conserving the world’s biological diversity.
• ensuring that the use of renewable natural resources is sustainable.
• promoting the reduction of pollution and wasteful consumption.
2. International Union for Conservation of Nature (IUCN)
The International Union for Conservation of Nature (IUCN) is
an international organization founded in October 1948, France.
In Nepal, it was established in 1994 AD, but it has been working
in Nepal since 1970 AD. It focuses on nature conservation,
biodiversity and nature based solutions. The mission of IUCN
is to influence, encourage and assist societies throughout the
world to conserve nature and natural resources.
3. Global Environment Fund (GEF)
Global Environment Fund is an international organization
founded in 1990 AD. It was founded on the principle that
well-deployed capital can bring significant improvement in
the environment and quality of life throughout the world.
The mission of GEF is to conserve energy, environment and
natural resources.
4. National Trust for Nature Conservation
National Trust for Nature Conservation (NTNC) is an
autonomous non-governmental organization of Nepal.
It was established in 1982 to work in the field of nature
conservation and sustainable development in Nepal. The trust
is supported by a network of international partners. NTNC
has successfully undertaken many small and large projects
on nature conservation, biodiversity, tourism, development
management and sustainable rural development. At present,
NTNC manages Annapurna Conservation Area Project (ACAP) and Manaslu
Conservation Area Project (MCAP) together with other projects in and around
national parks and wildlife reserves.
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 271
5. United Nations Environment Programme
The United Nations Environment Programme (UNEP) is the
agency of the UN that coordinates United Nations Environment
Activities. It was founded in June 1972. It assists developing
countries including Nepal in implementing environmentally
sound policies and practices.
Summary
• Environmental degradation is the damage or disturbance in any aspect
of the environment due to human activities and natural disasters.
• The reduction of the capacity of the environment to meet social and ecological
objectives and needs is called environmental degradation.
• Deforestation is the permanent destruction of forests or clearing trees in order to
make the land available for other uses.
• Increasing population is creating pressure on the natural resources. Therefore,
natural resources are being depleted day by day.
• Animals and birds lose their food sources and habitats due to deforestation. The
number of herbivores and carnivores is decreasing due to deforestation.
• Human beings use water for drinking, irrigation, generating hydroelectricity, fish
farming, industrial uses, etc.
• Green plants use solar energy to prepare their own food during photosynthesis.
• We should use mineral resources wisely and judiciously so that they may last as
long as possible.
• The sudden shaking of the earth’s surface is called earthquake. It occurs due to
sudden release of energy in the earth’s surface.
• A volcano is a place on the earth’s surface where molten rocks, gases and debris
erupt through the earth’s crust.
• Environmental sanitation is the creation of clean and hygienic environment around
us which is essential for maintaining good health.
• We should generate public awareness, plant trees, conserve forests and cultural
resources to conserve environment.
• Various national and international organizations and agencies are involved in
conservation of the environment.
Exercise
1 Fill in the blanks with appropriate words.
a. Flood, landslide, earthquake, etc. are ..............................
b. Deforestation may cause extinction of ..............................
c. .............................., urbanization and .............................. are the major causes of
.............................. degradation.
d. The molten mass of metals inside the earth’s crust is called ..............................
272 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
e. The full form of NTNC is ..............................
f. United Nations Environment Programme was founded in ..............................
2 Tick (√) the correct statement and cross (×) the incorrect one.
a. Deforestation increases the amount of carbon dioxide in the atmosphere.
b. We should run to an open place during an earthquake.
c. Volcano eruption does not pollute air .
d. We should conserve and promote cultural resources.
e. IUCN was established in 1948.
3 Answer the following questions.
a. What is environmental degradation? Mention any three natural causes
behind it.
b. What is deforestation ? Write any five causes of deforestation.
c. Mention any four effects of deforestation.
d. What is urbanization ? What are its effects on the environment ?
e. What is meant by industrialization ? Write in brief.
f. What are natural disasters ? Give any two examples.
g. What is an earthquake ? Write down its major causes and effects.
h. What is volcano ? Write any two causes and effects of volcano eruption.
i. What is environmental sanitation ?
4 Write short notes on:
a. Vegetation b. Urbanization
d. Minerals
c. Water resources
5 What do you mean by ‘Reduce, Reuse and Recycle’ ?
6 What efforts have been made by local people to conserve environment? List any
four of them.
7 Name any two governmental agencies and any four non-governmental agencies
involved in environmental conservation.
8 Write down the major goals and functions of Ministry of Science, Technology
and Environment in Nepal.
9 Write down the major aims and functions of Ministry of Forests and Soil
Conservation in Nepal.
10 Write down the full form of
a. IUCN b. WWF c. GEF
NTNC
d. UNEP e.
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 273
Unit Estimated teaching periods: Th Pr
10 2
24
Environment and Sustainable
Development
Objectives
After completing the study of this unit, students will be able to :
·• explain the concept of sustainable development.
·• describe the need and importance of nature–friendly development.
·• explain the efforts for sustainable development in the context of Nepal.
Course of Study
·• Concept of development
·• Development and environment
·• Concept of sustainable development
·• Nature–friendly development
·• Efforts for sustainable development in the context of Nepal
Points to be Focused / Questions to be Discussed
·• What are ‘development’ and ‘environment’ ?
·• What is meant by sustainable development?
·• What is nature–friendly development ? Why is it important?
·• What are the efforts for sustainable development in the context of Nepal?
274 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
24.1 Introduction
The physical and biological world around us is called environment. All the
organisms get necessary materials like air, water, food, shelter, etc. from the earth.
Environment includes plants, animals, micro-organisms, air, water, soil, sunlight,
etc. So environment is the totality of all living beings and non-living things.
24.2 Concept of Development
The act or process of making improvement to meet human requirements or
objectives is called development. Human beings do various activities for their
benefit. These activities make their lives easy. Construction of roads, buildings
and bridges, generation of hydroelectricity, establishment of factories and
industries, construction of canal for irrigation, etc. are all development works. All
these development activities are deteriorating the natural environment. Human
beings can modify natural environment to fulfil their necessities. When natural
environment gets deteriorated, the development works do not become sustainable.
24.3 Development and Environment
Human beings do not always use natural resources wisely and economically.
The overuse of natural resources affects the natural environment. Human beings
modify the form, shape and features of natural resources to fulfill the demands of
increasing population. The possibility of landslide increases due to deforestation
and cultivation in slopes. Similarly, construction of road, bridge, dam, etc.
and establishment of factories and industries affects the natural environment.
Development works also get affected due to environmental degradation. Flood
and landslide affect the development works. Therefore, environment should not
be affected while doing development works. The development works which do
not affect environment will be sustainable. Such development is called sustainable
development.
24.4 Concept of Sustainable Development
We should conduct development activities in accordance with the bearing capacity
of natural resources without affecting the environment. Natural resources should
not be used excessively to satisfy the demands of increasing population. Excessive
use of natural resources affects environment adversely and it will be difficult for
animals to live. The concept of sustainable development has been developed to
prevent the problems that will arise in the future.
Sustainable development is the combination of two words ‘sustainable’ and
development. Sustainable means capable of being around for a long time and
sustainable /səˈsteɪnəbl/ - involving the use of natural products and energy in a way that does
not harm the environment
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 275
development means growth. Therefore, in other words, sustainable development
is related to those developmental activities which do not degrade the environment
and can be carried on for a long time. Thus, sustainable development includes:
(i) living within the limits of consumption of natural resources,
(ii) realizing the interconnections among various developmental aspects and
environment, and
(iii) equitable distribution of resources and opportunities.
Therefore, sustainable development refers to the use of natural resources at present
without damaging their condition for the future generations.
Sustainable development is also called retaining development or bearable
development. The main objective of sustainable development is to maintain
balance among population, natural resources, components of environment and
development.
Sustainable development is the development that can be maintained for a long
time. Therefore, human beings can take benefit from sustainable development for
a long period of time. Sustainable development does not degrade the environment.
It helps maintain the natural resources for a long time. As a result, environment
remains in balanced condition. It does not affect the life cycle of the living beings.
Thus, sustainable development is the need of the world. The benefit of sustainable
development can be achieved in local, national and international level.
Activity 1
• Observe any one of the developmental works among road, bridge,
building, etc. in your locality. On the basis of your observation, find
out the answers to the following questions:
• What natural resources are used in that developmental work?
• What are the adverse effects of that development work on the environment?
• On the basis of the solutions to above questions, prepare a short report
and submit to your subject teacher.
24.5 Nature–Friendly Development
The main aim of sustainable development is to protect nature and natural resources
with their wise and judicious use. It is necessary to protect nature, environment
and its components for sustainable development. Developmental works should be
carried out without destroying nature and its resources.
The development carried out without affecting nature and its resources is called
nature–friendly development. We should conduct development activities according
to the bearing capacity of the natural resources and environment.
276 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
Conservation and promotion of nature and its resources is the common duty and
responsibility of all human beings. Some human activities promote the environment
while some activities of human beings affect the environment adversely. We should
either stop or modify the developmental activities that affect the environment to
reduce their impact on the environment.
Nature–friendly development not only conserves nature but also helps satisfy
needs of human beings. It also saves natural environment. According to the concept
of sustainable development, economic benefit should be gained with a limited use
of natural resources. In order to make developmental activities nature–friendly,
following points should be taken into consideration.
(i) We should reduce air pollution
The amount of harmful gases in atmosphere is increasing day by day due to
increase in the number of industries, factories and vehicles. Unmanaged industries,
increase in number of vehicles, wastes of humans and animals are major sources of
air pollution. To reduce air pollution, we should develop technologies that reduce
the emission of poisonous gases from vehicles and industries. We should establish
factories and industries away from human settlement. We should reduce the use of
fossil fuels, insecticides and pesticides to control air pollution. It helps to conserve
the environment.
(ii) We should conserve water resources
Living beings cannot survive without water. Water is the basis of life. Therefore,
we should conserve water resources. We should not destroy water resources while
constructing roads, buildings, factories, etc. We should plant trees around the
sources of water. We should reduce water pollution. It helps to conserve water
resources and natural environment.
(iii) We should conserve land
Nowadays people are using cultivable land for housing and establishing cities and
industries due to population growth. It may bring crisis of land for farming which
leads to food crisis in the near future. So, it is necessary to conserve land for farming.
Similarly, we should plant tress on slopes and bare land. We should manage waste
materials properly to reduce land pollution.
(iv) We should conserve rivers, lakes and other water resources
Water resources are getting deteriorated due to human activities. We are facing
water crisis in urban as well as rural areas. Many development activities affect
water resources adversely. Therefore, development activities should be conducted
by conserving water resources like river, lake, wetland, watershed, etc.
In this way, we should conduct development activities without affecting air, water
and land. Such development lasts long and becomes sustainable. Nowadays, it is
compulsory to conduct development activities only after environmental impact
assessment (EIA).
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 277
24.6 Efforts on Sustainable Development in Nepal
The concept of sustainable development is not a new concept. In the past also,
people used to consult seniors or specialists regarding the sustainability before
making a plan for a development project. People used to conserve natural resources
to save them for successive generations. People used to plant trees on bare land
and around water resources. Various activities are being conducted in Nepal for
making development activities sustainable. Some of them are mentioned below:
(i) Efforts have been started to save natural resources for future by minimizing
their use as far as practicable.
(ii) Efforts have been started to conserve forest resources by discouraging
deforestation and encouraging afforestation.
(iii) Protected areas like national parks, wildlife reserves, conservation areas, etc.
have been established to conserve wildlife and natural environment.
(iv) Environmental impact assessment is being conducted before starting
development works to conserve natural resources.
(v) Development of eco-tourism has been started to conserve natural environment.
(vi) Concern of local people is being increased in development works and
environment conservation.
(vii) Students and local people are being educated and encouraged for environment
conservation.
(viii) Various organizations and agencies have been established for environment
conservation.
Activity 2
• Observe various activities conducted by local people for ten days. Which
of these activities promote sustainable development ? Write with suitable
reason.
Project Work
• Prepare a short report after observing the development activities in your
locality. Explain with reason whether these activities are nature–friendly or
not.
278 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
Summary
• The physical and biological world around us is called environment.
• The process of making improvement to meet human requirements or
objectives is called development.
• When natural environment gets deteriorated, the development works do not
become sustainable.
• The development works which do not affect environment will be sustainable.
Such development is called sustainable development.
• The concept of sustainable development has been developed to avert the
problems that will arise in the future.
• Sustainable development is defined as the development that meets the needs
of the present without compromising the ability of future generations to
meet their own needs.
• Sustainable development is the need of the world. The benefit of sustainable
development can be achieved in local, national and international level.
• It is necessary to protect nature, environment and its components for
sustainable development.
• The development carried out without affecting nature and its resources is
called nature–friendly development.
• Nature–friendly development not only conserves nature but also helps
satisfy needs of human beings.
• We should conduct development activities without affecting air, water and
land. Such development lasts long and becomes sustainable.
Exercise
1 Tick (√) the correct statement and cross (â) the incorrect one.
a. Environment does not include non-living things.
b. Development activities affect natural environment.
c. Sustainable development is also called retainable development.
d. Development and environment are inter-related to each other.
e. The development without affecting the environmental components
is called nature-friendly development.
2 Fill in the blanks with appropriate words.
a. The development that lasts long is called ...................
b. The living world and non-living world around us is called ...................
c. ................... development helps conserve natural resources.
ENVIRONMENT SCIENCE Oasis School Science and Environment - 7 279
d. Development work should be conducted on the concept of ...................
development.
e. The development without affecting natural resources is called ...................
development.
3 Answer the following questions.
a. What is environment ?
b. What is development ?
c. What is meant by sustainable development ?
d. Why is sustainable development necessary ? Give any three reasons.
e. What is meant by nature–friendly development ? Why is it important?
4 List the development activities that are being conducted in your locality. Which
of these activities are nature–friendly ? Write with reason.
5 What types of activities are being conducted in your locality for sustainable
development ? Write in brief.
6 How are environment and development inter-related? Explain in brief.
7 How can we make development activities nature–friendly? Describe.
8 What efforts have been made for sustainable development in Nepal ? List any
four of them.
280 Oasis School Science and Environment - 7 ENVIRONMENT SCIENCE
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