the sun, it is called winter solstice. In this condition the northern hemisphere has the
shortest day and the longest night but the southern hemisphere has the longest day and
the shortest night. On winter solstice, the northern hemisphere receives the weaker
and slanted rays of the sun, for a shorter time. It makes the northern hemisphere
much colder i.e., winter. On that day the southern hemisphere has summer.
The sun is vertically overhead on the two days, usually they are on 22 March (E4) and
23 September (E2) though the date may change because a year is not of exactly 365
days. These two days are termed equinoxes, meaning equal nights. Because on these
two days the entire world has equal days and equal nights. The 22 March is called
spring equinox and 23 September is called autumn equinox.
Beyond the Arctic circle and the Antarctic circle, the darkness lasts for 6 months and
day light is continued for the remaining half of the year. It is extreme cold in this
region and the sun is never high in the sky.
Four seasons in a year are winter, spring, summer and autumn
At the geographical poles, i.e. Arctic and Antarctic, days and nights occur for six
months.
Seasons of the year in the northern hemisphere
Winter 22nd December to 20th March
Spring 21st March to 20th June
Summer 21st June to 21st September
Autumn 22nd September to 21st December
The Sun
We know more about the Sun than any other star simply because it is so close to
us. Some large observatories have telescopes that are used only to study the Sun.
Astronomers want to know how the Sun works and how it affects the Earth. From
this we can understand how most of the normal stars work.
The Sun is a normal star and is about 4.6 billion years old. The surface temperature is
about 6000oC, but at the centre it is 14 million oC. In the Sun’s core, hydrogen burns
into helium, and this releases energy. On the surface there are sunspots and solar
flares, and great explosion can be seen.
The Sun is a fiery ball of gas, about 110 times larger in diameter than the Earth. The
yellow light of the Sun comes from a layer called the photosphere. Below this layer
lies the solar interior and above it parts of the outer atmosphere that are transparent.
Practically all of the Sun’s energy, including the heat and light which is falling on
Earth, comes from the photosphere, but was originally made deep inside the Sun.
Blooming Science & Environment Book 8 273
The sun is situated at a distance of 300,000 light years from the centre of the Milky
Way galaxy. 8 planets, 167 moons, numerous asteroids, comets, etc. are the family
members of the Sun. The sun is mainly composed of the elements hydrogen and
helium. It takes nearly 8 light minutes 20 seconds for the light to reach us from the
Sun. The mass of the sun is 1.99 x 1030 kg and the means radius of the approximately
spherical photosphere is 7.0 x 105 km. These figures are respectively 3.3 x 105 times
the Earth’s mass and 110 times the Earth’s radius. This volume of the Sun can
accommodate 1.3 million Earth.
The Moon
The moon is the natural satellite of the earth. Like planets,
the moon has no light of its own. It is visible to us on account
of reflection of sunlight from its surface. The moon has no
atmosphere and water. Its surface is covered with craters.
The moon is about 3,84,000 km away from the Earth. Its
diameter is 3,660 km. It revolves around the Earth in elliptical path. It also rotates
in its axis. The time of rotation of the moon is same as the time of its revolution. It
is 29.5 days.
Phases of the Moon
From earth it is not seen at waxing first waxing
the same shape and size. It is gibbous quarter crescent
seen in different shapes called full moon
phases of the moon. waxing last new moon
gibbous quarter waxing
As the moon revolves round crescent
the earth, its position with
respect to the sun and the earth
changes. When observed daily
for a month, its bright portion
changes. Someday, it appears as
a full disc. This phase is called
full moon or ‘Poornima’. On
the day, the sun and the moon
are on the two opposite sides of
the earth.
Similarly someday, it appears as a dark disc. This phase is called new moon or ‘Aunsi’.
On that day, the moon lies between the sun and the earth. The side facing towards the
earth does not receive sunlight. So it is dark. The moon is not seen in the sky at night.
The shape of bright (illuminated) part of the moon changes day by day. The change
in shapes of the moon as observed from the earth is called phases of the moon.
274 Blooming Science & Environment Book 8
Bright Half and Dark Half
Bright half is the phases of moon in which the bright surface of the moon increases
gradually and reaches maximum on the full moon day. It is the period between new-
moon to full moon. It is the first half of the lunar month. It is about 15 days.
Dark half is the phases of the moon in which the bright surface of the moon decreases
and finally becomes invisible on the new moon day. It is the period between full moon
and new moon. It is the second half of the lunar month. It is also about 15 days.
Main Points to Remember
1. Astronomy is the study and understanding of the universe beyond the Earth.
2. The Universe is the largest possible volume of space, together with all the
matter and radiation within it that can affect us in any way. There is only one
observable Universe in our sight.
3. Galaxy is the composition of billions of stars. It is an association of stars, dust,
and gas, with a total mass ranging from 106 to 1013 times the mass of the Sun.
4. The Sun is the nearest star. Next to the Sun, Alpha Centauri is the nearest star.
The surface temperature of the Sun is 6000oC and it is estimated that its inner
core has a temperature about 14 million oC.
5. The sun is situated at a distance of 300,000 light years from the centre of the
Milky Way galaxy. The mass of the Sun is 1.99 x 1030 kg and it is 3.3 x 105
times larger than the earth. It can accommodate 1.3 million Earths.
6. The moon is the only natural satellite of the earth.
7. The time of rotation and time of revolution of the moon is approximately same
which is about 29.5 days.
8. The moon changes its position when observed from the earth. It is called phases
of the moon.
PRO J ECTWORK
Draw the diagrams to show the change of season on the earth and phases of the
moon in a chart paper and paste it in your study room.
Blooming Science & Environment Book 8 275
Exercise
1. State whether the following statements are ‘True’ of ‘False’.
(a) The Sun is not a star.
(b) It takes 365 years for the earth to revolve round the sun.
(c) The distance travelled by the light in one year is called the light year.
(d) The moon completes one revolution around the earth in 29.5 days.
(e) The moon is completely seen in a new moon day.
2. Write brief notes on. b) Astronomical Unit
a) Planet d) Bright and dark half
c) Tidel hypothesis
3. Answer the following questions.
(a) What is the structure of the Sun? Detail the structure of the Sun.
(b) What is an Universe?
(c) Define diurnal and annual motion of Earth.
(d) Define bright half and dark half.
(e) What are phases of moon?
4. Distinguish between.
(a) Stars and Planets
(b) Dark half and Bright half
(c) Annual and Diurnal motion of the earth.
Glossary
Elliptical : in the shape of ellipse
Crater : a large hole in the ground caused by volcano
dwarf : very short
Universe : the vast empty space around us and every thing that is in it
Planet : heavenly body which revolves round the sun
Satellite : heavenly body which revolves round the planets
Asteroids : small large bits of rocks between Mars & Jupiter revolves
round the sun
Meteor : small heavenly body that moves round the sun
Meteorite : large meteor that reaches the earth without getting burnt
Constellation : groups of stars arranged in interesting patterns
Galaxy : a large cluster of star
Light year : the distance travelled by light in one year
Astronomical unit : the distance between the earth and the sun.
276 Blooming Science & Environment Book 8
Chapter Environment Science
22 Environment and Its
Balance
Learning Outcomes Estimated Periods: 12+3
on the completion of this unit, the students will be able to:
describe dependance of human beings on different natural resource like
food, habitat and herbs.
make a list of national park, wild life reserves and conversation areas.
describe present status of forest and its importance.
tell importance of wild life and endangered species.
introduce some endangered animals and birds of Nepal.
The resources which are created by nature freely for human use are known as natural
resources. These are not man-made but in their own original forms. Man has never
spent money on their formation. The soil, air, water, energy, mineral deposit, fish,
wildlife, forest, natural scenery, etc. are major natural resources. Man is also an
integral part of the environment. Natural resources are gifts of nature. Man and these
natural resources have close relationship. These natural gifts are equally important
resources for an individual, family, community and for a country as a whole.
Natural resources are our invaluable public and common property. Life only can
exist in nature. No life can exist without nature. All the natural resources are the
things of our daily consumption and utilization. So, we should use natural resources
properly for development work. Their conservation and promotion are also essential.
Blooming Science & Environment Book 8 277
Consumption of natural resources has increased due to population growth. Over
exploitation of natural resources has disrupted the natural balance in some places.
Natural resources are essential components for livelihood of human beings. It is
difficult for creatures to survive due to the depletion of natural resources. So, everyone
should be conscious about the environmental conservation. Human beings play a
vital role in the conservation of natural resources. It is essential to develop awareness
in every person about environmental conservation, preservation and promotion.
Rational utilization of natural resources is necessary for conservation and promotion
of environmental balance. So, everyone should take interest in the conservation and
promotion of natural resources. Public participation and environment education are
also necessary for its preservation.
Rapid population growth and
unwanted development of new
and modern technology have
made man’s life very easy but
it has begun to cause adverse
effects on the environment.
Waste products and polluted
materials from factories and
toxic smoke from automobiles
have polluted the environment.
It is true that human life has
become more comfortable
because of the development Fig: Human activities and environment
of means of transport, modern
agricultural tools and equipment, etc. but they have given undue pressure on the
natural resources. Such undue pressure is unbearable for the carrying capacity of
nature. Consequently, all the environmental components have been affected badly.
Therefore, development should be sustainable without disturbing the natural quality
and quantity of environmental components.
Over cultivation, overgrazing, unscientific irrigation system, deforestation,
unplanned industrialization and unmanaged urbanization have polluted air, water,
soil and sound in the environment. As a result, natural resources and means are being
destroyed beyond repair. Depletion of forests, unplanned extension of habitation,
unmanaged disposal of waste materials, misuse of pesticides, insecticides and
chemical fertilizer, etc. make the environment more polluted. Therefore, man must
preserve these resources by conducting different types of programmes with a view
to conserve and promote the natural resources. Natural and environmental balance
should be maintained among resources for better future on earth.
278 Blooming Science & Environment Book 8
Dependence of Man on the Environment
Suitable and healthy environment is necessary for the survival of living creatures.
Man, animals, insects and other living organism depend on other creatures,
vegetation and different types of
physical materials available in
their surroundings. Thus, living
creatures are deriving benefits
from the environment. They
survive well in clean, suitable
and healthy environment.
Unhealthy environment affects
them in their movement, growth
and makes their survival difficult.
The number goes on diminishing
in adverse environment. Fig: Forest ecosystem
All animals cannot survive in a similar type of environment. Some animals need
aquatic environment while others need aerial environment. Still some other animals
can live in and enjoy both types of environment. Thus, some living creatures need
terrestrial environment also.
The major resources of environment are air, water, soil, vegetation, minerals, and
living organisms found on the earth. Man is an integral part of the environment. Man
also depends upon different natural resources available in the environment.
Natural Resources
Perpetual Renewable Non-renewable
Solar Air Fresh Clean Fertile Vegetation/ Fossil Metal Non-metal
power power Air water Soil Animals Fuel Minerals Minerals
Status of Forests
Forest is the essential component of natural environment. Forest provides many
things to human beings, animals and birds to survive them. Without forest, life would
be very difficult on the earth.
The area of forest was 53.5 percent 25/26 years ago (B.S. 2026/27) in Nepal. Once
forests were national wealth of Nepal. But now the situation has greatly changed.
The growth of population has changed the situation of forest in many parts of Nepal.
Deforestation is rapidly increasing in many parts of the country. At present, the area
Blooming Science & Environment Book 8 279
of forests is 37 percent only by
census year 2001 A.D. Sal, Sesum,
Catechu, Satisal, Simal etc. were
there in large quantity in the Terai
and Inner Terai belt. The number
of these species are getting reduced
now. At present, Simal, which is
used for making match sticks, is
becoming scarce. Generally, the
houses are made of bamboo, grass,
etc. in villages and the canes are Fig: Dense forest
used for various purposes. This has
caused the scarcity of bamboo, cane and grass in the forest.
Only 11 percent forest is found in Terai and about 89 percent of forest is found in the
High Hills and Mid Hills. Coniferous forests are chiefly found in our country. Among
them, the natural coniferous is 59 percent, coniferous is 17 percent and remaining 24
percent are mixed.
1. Deforestation: Human demands have
increased with population growth. They
fell trees to fulfill their requirements.
Various other factors are responsible for
deforestation. It is found that people are
clearing the forest for various purposes
such as land for agriculture, fuelwood,
timberwood, grass, residence and raw
materials for industries. The forest has
to bear more pressure only because the
agriculture is the only sector having opportunities for employment. Husbandry
is directly related with agriculture. Farmers keep cattle in large numbers. They
make them graze in open place and in the forest. It causes overgrazing. It
adversely affects the forests. In this way, the signs of desertification have been
increasing.
2. Importance and Necessity of Forests: The forest plays an important role in
our life. The importance of forest can be listed as follows:
• The forest has a great role to play in regulating climatic condition.
• The forest is the storehouse of oxygen which is vital for living beings.
• The forest is the habitat for a large number of wildlife species.
• The forest supplies food, fuelwood, timberwood and fodder to man and
animals.
280 Blooming Science & Environment Book 8
• The forest is necessary for conservation of soil.
• The forest is the main regulator of water supply for all purposes.
• The forest also supplies herbs, fruit and flowers to man.
• The forest protects the soil from erosion and stops landslides.
• The forest in the hills hold soil strongly, which helps to prevent the soil
from being transported.
Therefore, measures should be taken to conserve our forests in time.
3. Attempts for the Conservation of Forests: Attempts have been made at the
government and NGO levels. The public awareness programmes have been
launched in different parts of Nepal. The community forest programme is
gaining importance in many places. At present, the country needs to conserve
forests, and it can be made by the government as well as public levels.
Activity
Observe a forest, a park or a garden. Find the answers to the following questions.
• Which species of plants are there in the forest/park/garden?
• What are the uses of the forest/park/garden?
• What efforts seem to be necessary to protect the forest/park/garden?
Now write about forests on the basis of the following notes.
(a) Status of forests (b) Uses of forests
(c) Humans impact on forests (d) Efforts needed to protect forests
Major Plants and Animals of Nepal
Geographically Nepal extends 900 km from east to west in length and 200 km from
north to south in wide. The total area of Nepal is approximately 1,47,181 sq.km.
About 73% of the total land is covered by the hills, mountains and the Himalayas.
The plains of terai and inner terai cover about 27% of the total land of Nepal. Nepal
has all kinds of landscapes and climates. The climate changes according to altitude.
Different kinds of flora and fauna are found at different altitude. Environment has
great effect on the plant and animal at different altitudes in Nepal. The geographical
structure of Nepal can be divided into three regions :
(a) Terai and Bhawar Region (b) Mountain Region and
(c) Himalayan Region
Blooming Science & Environment Book 8 281
Pea plant Bean plant Paddy
(a) The Terai Region
The Terai has hot temperature climate. The soil is more fertile. Generally tall
and timber producing trees Sal, Sissoo, Simal, Khayar, Asna, Karma etc. are
found.
Besides these tall trees, tall grasses like saccharum and Typha popularly known
as jhari are also found in this region. The tropical forest and grassy area provide
habitat for many wild animals like elephant, tiger, leopard, rhino, wild buffalo,
deer, swamp deer, etc. Timber are used for many purposes and grass plants are
used as the raw materials for paper industry.
(b) Mountain Region
This region has mountains. It contains a narrow strips of low land with river
banks and big valleys like Kathmandu, Pokhara and Surkhet. It lies between
1500 m to 3000m and covers a large part of the country. In this region,
the climate is cool, humid and pleasant and hence in general the climate is
temperate. Different types of trees and herbs are found in this region according
to the climate. The important trees found in this region are Katus (Castanopsis
indica), Okhar (walnut-Juglans regia), Salla (Pinus species), Utis (Alnus
nepalensis), Baanjh (Quercus gluca), Chilaaune (Schima wallichii), Guraans
(Rhododendron companulatum), Oak (Quercus species), Paiyun (Prunus
cerasoides), Deodar (Cedrus deodara), Chaanp (Michalia champaca) etc.
(c) The Himalayan Region
The Himalayan region lies north of the central mountain which extends from
2500 to 8000 m. Most of the peaks of this region are covered with snow.
The climate is cold and snowy in winter. Most of the trees are found only
upto 4000m while the grass and other vegetation like shrubs are found upto
4500m. The important trees found in this region are Lek sallo (Pinus wallichii),
Thegure sallo (Tsuga brunoniana) Larch (Larix sps), Guraans (Rhododendron
companulatum), Devdar (Cedrus deodara), Elma (Ulmus wallichiana) Maple
(Acer Compbellii) etc.
282 Blooming Science & Environment Book 8
Timber Plants
All trees produce wood which is used as fuel. Usually low quantity wood is used as
fuel. The wastage of quality wood is also used for fuel. Wood from trees such as sal,
sissoo, pine, deodar, etc., is hard and is good quality wood which is used for making
furniture and constructing houses, bridges etc. It is known as timber.
Sissoo tree Sal tree
According to the climate, the plants found in different regions are given below:
S. No. Common name English name Scientific name
1. Saal Common sal Shorea robusta
2. Sissoo Silk cotton tree Dalbergia sissoo
3. Simal Cutch tree Bombax ceiba
4. Khayar Acacia catechu
5. Karmaa Chestnut Adina cardifolia
6. Asnaa Terminalia tomentosa
7. Katus Castanopsis indica
8. Utis Alnus nepalensis
9. Chilaaune Schima Wallichii
In the Mountain Region: Temperate Climate
S.No. Common name Scientific name
1. Daale Katus Castanopsis indica
Alnus nepalensis
2. Utis Schima wallichii
Jaglans regia
3. Chilaaune Pinus roxburghii
Michalia champaca
4. Okhar Prunus cerasoides
5. Raani Sallaa
6. Chaanp
7. Paiyun
Blooming Science & Environment Book 8 283
In the Himalayan Region: Alpine Climate
S.No. Common name Scientific name
1. Dhupi Cupressus torulosa
2. Gobresallo Abies pindrow
3. Guraans Rhododendron campanulatum
4. Devdar Cedrum deodara
5. Thegure sallo Tsuga brunoniana
6. Maple Acer compbellii
7. Talispatra Larix griffithiana
8. Bhojpatra Betula utilis
9. Sprus Picea morinda
10. Elma Ulmus wallichiana
Medicinal Plants
Medicinal and Aromatic plants are the valuable forest resources of Nepal. A number
of medicines in use today are obtained from plants. In Nepal, the medicinal value
of plants such as neem, amla or tulasi have been known for thousands of years.
Quinine, the medicine used for the treatment of malaria, is obtained from the bark of
the cinchona plant. These medicinal plants grow abundantly in different ecological
regions due to the diversity in climate and other ecological factors.
Extracts of dhatura and poppy seeds serve as pain killers and sedative. Neem leaves
have antiseptic properties. They are used to make antiseptic soaps and medicines for
skin. The different parts of the plant like roots, stems, leaves, fruits and seeds are
used for medicinal purposes to cure many diseases.
Thus, we see that there are different types of medicinal herbs in Nepal. Some of
them are cultivated and some are wild. They are used after drying or powdering
or after mixing with other herbs. Some private particitioner (Ayurbedic Baidya)
use medicinal herbs to make medicine.
Many herbs are also used in Singha Durbar
Baidyakhana for making medicines. Due
to the increasing demand, attempts have
been made in cultivating herbs and produce
medicines under Government level i.e. the
Department of Medicine plants, Nepal Drug
Ltd. and Herbs production and Processing
Company Ltd., Koteshwor, Kathmandu.
284 Blooming Science & Environment Book 8
The medicinal plant has a good recognition in the Indian market since ancient times.
During the past years our country shows that about 600 varieties have been identified.
Some raw herbs are exported to other overseas countries also. It is estimated that
nearly 60 species of medicinal plants are exported to foreign countries.
The species of medicinal plants differ in different climatic condition. The plants found
in hot climate are different from those found in cold climate. In the hot and humid
climate of Terai region, plants like Harro (Terminalia chebula), Barro (Terminalia
berelica), Rajbriksha (Cassia fistula), Sarpagandha (Rauwolfia serpentine), Amala
(Emblica officinalis), Asuro (Adhotoda vasica) etc. are found.
Some medical plants of different altitudes are given below.
Medical Plants of Tropical Climate
S. No. Common name Scientific name
1. Harro Terminalia chebula
Terminalia belerica
2. Barro Cassia fistula
Emblica officinalis
3. Rajbriksha Adhatoda vasica
Piper longum
4. Amla
5. Asuro
6. Pipala
In Mahabharat range, the climate is temperate. The plants found in this region are
given below:
Medicinal Plants of Temperate Climate
S. No. Common Name Scientific Name
Berberis aristata
1. Chutro
2. Kaalo dhaturo Datura metal
3. Chiraaita Swetrtia chitra
4. Bojho Acorus calamus
5. Sugandhawal Valeriana wallichii
6. Timur Zanthoxylum armatum
7. Beladonna Atropa belladonna
8. Tejpaat Cinnamomum tamala
9. Sarpagandha Rauwolfia serpentna
10. Vyaakur Dioscorea deltoidea wall
Blooming Science & Environment Book 8 285
Timur Bojo Plant
The Himalayan Region is cold throughout the year. The following main plants are
found in this regions:
Medicinal Plants of Alpine Climate
S. No. Common name English name Scientific name
1. Bikha
Aconitum palmatum
2. Paanchaunle Orchis latifolia incarnata
Aconitum heterophyllum
3. Atis Atis root Rheum emodi wall
Nardostachys jatamansi
4. Padamchaal Rhubarb
5. Jataamasi Spikenard
Paanchaunle Jataamasi
Ornamental Plants of Nepal Marigold
Plants which look beautiful are grown in gardens, parks
and flower pots for decoration are known as ornamental
plants. The most prominent are those with beautiful
flowers. Others such as crotons or money plant have
beautiful leaves. Some herbs and shrubs are planted for
decorative purpose in the gardens.
Plants used for decorative purpose are Sunflower,
Marigold, Makhamali phool, Croton, etc.
286 Blooming Science & Environment Book 8
Some plants found in the different parts of country are also used as ornamental
plants. For example, Lalupate, Asareful, Laligurars, etc. enrich the beauty of our
surroundings. Plants such as Makhamali, Sunflower, Sayapatri, Godavari etc. are
planted in our surrounding for decoration.
Those plants which add beauty to our surroundings are called ornamental plants.
Food Plants
Plants are the main source of food. Food plants can be grouped into cereals, legumes,
vegetables and fruits. Paddy, wheat, maize etc. plants have monocotyledonous seeds
and these crops are known as food crops. Different types of plants like peas, soyabean,
beans, grams etc. have dicotyledonous seeds and these are known as leguminous
plants. We use different parts of plants as food. Leaves of cabbage, radish, spinach
are used as curry while the stems of plants like ginger, sweet-potatoes etc. are also
used as food. Fruits of some plants like pumpkin, cucumber, tomatoes, brinjal, chilli
etc. are also used as food.
Most of the plants are cultivated and used by man for his benefit. But these are some
plants which are harmful. Bacteria and fungi are plants which cause many diseases
in plants and animals. They spoil out food.
Wheat rust which causes damage to wheat crop is caused by fungus. Pollen grains
of some plants cause allergy to many people. Some plants yield intoxicating drugs.
Wildlife and Forest Conservation
Wildlife includes all non-cultivate and non-domesticated life in its natural
surroundings. It includes game and fur-bearing vertebrates, and even plants and non-
game animals which do not interact directly with the game species. In other words,
the native population of a community comprises its wildlife.
Wildlife, like the forests, is another valuable asset of nature. Dense forests are
essential for the survival of wild animals. Because of the fact that forest areas are
decreasing the wildlife species are becoming extinct.
Some birds of Nepal like danphe, monal, koklas, pheasant, cheer pheasant, blood
pheasant are found in the northern part of the Himalaya.
Deer Jackal Elephant
Blooming Science & Environment Book 8 287
The hilly region and the plains of the terrain are the storehouse of wild animals and
plants. The following animals are found in the terai and inner terai.
1. Elephant 2. Tiger 3. Samber deer 4. Wild boar
5. Black buck 6. Fox 7. Wild dog 8. Spotted deer (chital)
9. Common Langur 10. Leopard 11. Crocodile 12. Rhinoceros
13. Barking deer 14. Swamp dear 15. Wolf 16. Jackal
17. Wild buffalo 18. Gaur, etc.
The following animals are commonly found in the northern hilly region and
mountainous region.
1. Jharal 2. Red panda 3. Snow leopard 4. Ghoral
5. Muske deer (Kasturi) 6. Wild dog 7. Munt jak 8. Wild boar
9. Sirow, etc.
Dove Peacock Danfe
Endangered Animals
Deforestation and indiscriminate hunting had led to a depletion of wildlife. Wildlife
includes all plants and animals that are not domesticate. In recent years, the
population of many wildlife species have been decreasing, mainly due to changes in
the environment brought about man. He has cleared forests and converted grasslands
into farmlands. This has destroyed the habitat of the wildlife and upset the delicate
balance of nature. Animals that cannot adjust to the environmental changes begin to
die, and some species become endangered as their population becomes very small.
If the species is not protected, they may become extinct. Some animals like Blue
sheep, Tiger, Rhinoceros, Leopard, Elephant, Wild buffalo, Snow leopard, Musk
deer, Swamp deer, Gangetic Dolphin etc. are endangered while some other animals
like Pygmy hog, Black buck, Wild ass, Hispid hare etc. are becoming extinct.
288 Blooming Science & Environment Book 8
Some of the endangered animals and birds are:
Mammals Birds Reptiles
Black Stork Python
Assami monkey White necked stork Crocodile (Gharial)
Salak Crane Sun Gohoro
Wild Wolf Impeyan Pheasant
Pygmy Hog Hornbill
Wild Ass Cheer pheasant
Hispid Hare Crimson-horned pheasant
Gangetic Dolphin Danphe
Black Buck Munal
Snow Leopard
Musk Deer
Wild buffalo
Wild elephant
one-horned rhino
Wolf
Similarly some more animals going to be extinct from Nepal are one-horned rhino,
Bengal Tiger, Asiatic elephant, Red panda, Python and Giant Pied Hornbill (Dhulo
Dhanes),etc.
Musk deer Snow leopard
Attempts to Conserve the Wild Life
As many people migrated from hilly region to terai region and started clearing the
forest for shelter and agriculture, the habitat of wild animals is destroyed. Increase
in population, cultivation, deforestation, grazing of domestic animals in the forest
damage the habitat of wild animals. It has given a serious threat to the existence
of wild animals. To conserve and protect the wild animals, Nepal government has
established national parks and wildlife reserves.
National Park
A national park is a separate reserve area for the production and management of wild
flora and fauna in their natural habitat including surroundings. Nepal has following
National parks.
Blooming Science & Environment Book 8 289
1. Chitwan National Park
Chitwan National Park is the first national park established
in Nepal. It was established in 2030 B.S. It lies in chitwan,
Parsa, Makawanpur and Nawalparasi districts with an
area of 932 square kilometre. It has been kept in the list
of world heritage site since 2041 B.S. by UNESCO. Sal
is the famous plant found in this national park . Other important plants are sisoo,
balsasm, grasslands etc. The main animals found in this national park are Bengal
tiger, One-horned rhinoceros, Bear, Leopard, Phython, Spotted dear, Alligator,
Magar crocodile, Ratuwa, Laguna, Red monkey, Langur, Peacock etc.
2. Sagarmatha National Park
Sagarmatha National Park was established in 2032 B.S in
Solukhumbu district. Its area is 1148 square kilometre and
it consists of world’s highest peak Sagarmatha. There are
other mountains like Lhotse, Nupse, Pumari, Amadablum
and Thamsherku in this national park. The plants like
Gobre salla, Thigure salla, Dhupi, Bhojpatra,Laligurans
etc are found in lower part of this national park. The
important animals found here are Musk deer, Deer, Mountain bear, Thar, Ghoral etc
and some birds like Danphe, Chilime, Kalij,Snow cock, Lalchuchche etc.
This national park has been kept under world heritage list by UNESCO since
2039 B.S.
3. Langtang Natinal Park
Langtang National Park is another national park
established in Himali region. It was established in 2032
B.S. in Rasuwa, Nuwakot and Sindhupalchok districts.
Its area is 1710 square kilometre. A famous holy place
Gosainkunda and a mountain Langtang lie in this national
park. The important plants found here are khotesalla,
Kharsu, Rhododendron, Fir, Birch etc and important
animals are Snow leopard, Red Panda, Musk deer, Mountain bear, Thar, Ghoral,
Red monkey etc.
4. Rara National Park
Rara National Park, popular for Rara largest lake of Nepal
was established in 2032 B.S. It covers an area of 106 squre
kilomatre in Mugu and Jumla districts. It is the smallest
national park of Nepal. It is famous for coniferous trees
290 Blooming Science & Environment Book 8
like Gobre salla, Fir, Oak, Birch etc. The important animals found in this area are.
Himalayan bear, Thar, Ghoral, Musk deer, Black boar etc. Birds from Syberia and
Mansarobar come to this area in winter.
5. Shey-Phoksundo National Park
Shey- Phoksundo National Park, the largest national park
of Nepal was established in 2040 B.s. It lies in Dolpa
and Mugu districts and covers an area of 3555 square
kilometre. There is Phoksundo lake and Shey gumba
(monastery) in this national park. Wild animals like snow
leopard, Hare, Himalayan bear, Musk deer and verities of
birds are found in this region. The important plants of this area are Rhododendron,
Juniper Birch and other Himalayan plants.
6. Khaptad National Park
Khaptad National Park was established in 2042 B.S. It
covers an area of 225 square kilometre and located in
Bajhang, Bajura, Doti and Achham district of seti zone.
The important plants of this park are Salla, Kharsu, Red
forest and grassland whereas the important animals are
Ratuwa, Kasturi, Ghoral, Leopard, Wilddog, Wild cat
and birds like Danphe, Munal, etc.
7. Bardiya Nationa Park
Bardiya National Park is a terai based National Park
established in 2045 B.S. It covers an area of 968 square
kilometre of Bardiya district. It is important for Sal
forest and grass land. This park is famous for wild
animals found in Terai region like Bengal tiger, Leopard,
Krishnasar, Gaur, Spotted dear, Stag, Laguna, Alligator
Magar crocodile, Dolphin, Wild elephant and different
birds.
8. Makalu Barun National Park
Makalu Barun National Park is one of the famous park of
eastern Nepal. It was established in 2014 B.S. It covers an
area of 2330 square kilometre. It lies in Sankhuwasabha
and Solukhumbu districts. It is named after Makalu himal
and Barun valley. It consists of varities of plants like
Sunapati, Aromatic grasses, Sungabha, Wild rose, Gobre
salla, Thigure salla, Bhojpatra, Rhododendron, Arkhauli
Blooming Science & Environment Book 8 291
and Phirphire. The important animals of this park are Habre, Snow leopard, Tibetan
hare, Himalayan bear, Thar, Musk deer, Himalayan mouse, Ghoral etc.
9. Shivapuri Nagarjun National Park
Shivapuri Nagarjun National Park is the nearest park
of Nepal from capital city. It was established in 2058
B.S. It is located in Kathmandu, Nuwakot, Dhading and
Sindhupalchowk districts. Its area is 159 square kilometre.
It is famous for different species of mushrooms, plants of
hilly region and butterflies. The important animals of this
park are Clouded leopard, Spotted deer, Salak, Wild cat, Mangoose, Langurm, Wild
boar, Ratuwa, etc.
10. Banke National Park
Banke National Park one of a Terai based National Park
was established in 2047 B.S. It is located in Banke, Dang
and Salyan districts. Its area is 550 square kilometre.
This park consists of Sal, Sisoo, Khayar and grass lands.
The important animals found here are Tiger, Alligator,
Elephant, Leopard, Wild boar, Spotted deer, Deer, Gaur,
Laguna, etc.
11. Shukaphant National Park
Shuklaphant National Park was established as a wildlife
Reserve in 2032 B.S. whereas converted into National
Park in 2073/11/09 B.S. It is situated in Kanchanpur
district and covers the area of 305 square kilometres. Its
forest is covered by sal sisoo, khayar and grasslands. It is
very important for the presence of Antelope (Barasinge).
The other main animals found here are Bengal tiger, wild boar, Bear, Leopard, Gaur,
Stag, Spotted deer, etc. Local and migrated birds of different species are found in this
park.
12. Parsa National Park
This is the youngest National Park of Nepal established
in 2074/02/19 B.S. as a National park. It is located in
Parsa, Bara and Makawanpur districts with an area of
637 square kilometres. It is covered with Sal, Sisoom,
Khayer, etc and the major animals of this park are wild
elephant, Tiger, Gaurigai, Leopard, Antilope and varities
of birds.
292 Blooming Science & Environment Book 8
National Parks of Nepal
S.N Name of Area in Establish Location Common animals
and plants found
National sq.km. in
Park
1. Chitwan 932 1973 AD Chitwan, Tiger, bear, leopard,
National (2030 BS) Makwanpur & python, one-horned,
Park Parsa rhinoceros, peacock,
19 July sal, sisoo, balsam,
2. Sagarmatha 1148 1976 AD Solukhumbu etc.
National (2032 BS) Kasturi, thar, ghoral,
park Rasuwa, jharal, lophophorus,
1976 AD Nuwakot kalij, himkukhura,
3. Langtang 1710 (2032 BS) and gobre sallo,
national Sindhupalchok bhojpata, dhupi,
Park 1976 AD rhododendron, etc.
(2032 BS) Mugu Leopard, red
4. Rara 106 1984 AD and panda, himalayan
(2040 BS) Jumla bear, thar, ghoral,
National Dolpa khotesalla,
and kharsu,
Park Mugu rhododendron, fir,
birch, etc.
5. She-phoksundo 3555 Himalayan bear,
kasturi, gobre sallo,
National Park fir, oak birc, etc.
Himalayan leopard,
tibetan hare,
varities
of birds, himalayan
tree rhododendron,
juniper, brich, etc.
Blooming Science & Environment Book 8 293
6. Khaptad 225 1984 AD Bajhang, Bajura Kasturi, ghoral,
National Park (2042 BS) Doti, and leopard, wild
Achham dog, red, monkey,
danphe, munal, oak,
pine, etc.
7. Bardiya 968 1988AD Bardiya Bengal tiger,
National Park (2045 BS) leopard,
black deer, spotted
dear, wild elephant,
varities
of birds sal, sisoo,
grassland, etc.
8. Makalu Barun 1500 1992 AD Sankhuwasabha Kasturi, ghoral,
National Park
(2049 BS) and himalayan thar,
Solukhumbhu rhododendron,
juniper, etc.
9. Shivapuri 159 2002 AD Kathmandu, Spotted deer,
Nagarjun (2058 BS) Nuwakot and leopard,etc.
National Park Sindhupalchok
10. Banke National 550 12 July 2010 Banke, Bengal tiger,
Park AD Salyan leopard, spotted
(2067 BS) and dear, wild elephant,
Dang varities of birds sal,
sisoo, grassland, etc.
11. Shuklaphanta 305 2017AD Kanchanpur Wild elephant,
National
Park (2073 BS) red tiger, leopard
12. Parsa National 637 antelope, spotted
Park
deer, etc.
2017 AD Parsa, Bara and Wild elephant,
(2074BS) Makwanpur antilope and
various
birds.
294 Blooming Science & Environment Book 8
Wildlife Reserves
A wildlife reserve is an area of land that is protected and managed inorder to preserve
a particular type of habitat and its flora and fauna which are offer rare. Basically
reserves are the areas separated for the conservation of wild animals and birds. There
is only one i.e. Koshitappu wildlife reserve in Nepal.
Koshitappu Wildlife Reserve
Koshi Tappu Wildlife Reserve is a protected area in the eastern terai of Nepal. It is
located in Sunsari, Saptari and udayapur districk in the flood plain of the Sapta Koshi
river. its area is 175 square Kilometre and established in 1976 AD. various plants like
eel grass, catechu, kapok, etc. and various animals like asian elephant , wild boar,
spotted deer, water buffalo, watercock, black-headed cuckooshrike, etc are found in
this reserve.
Hunting Reserves
A hunting reserve is a large area of land where people are allowed to hunt the wild
animals in a controlled way. The only hunting reserve in Nepal is Dhorpatan Hunting
Reserve.
It is located in the Baglung, Myagdi and Rukum districts. It covers an area of 1325
sq.km and established in 1987 AD. It is the habitat of many mammals and birds like
snow leopards, musk deer, red panda, bluesheep, koklass pheasaw, cheer pheasant,
impeyan pheasnat, etc.
Conservation Areas
A conservation area is an area of notable environment which is protected by law
against undesirable charges. The conservation area is established for the biodiversity
conservation of particular area. There are six conservation areas established in Nepal.
They are:
i. Annapurna Conservation Area ii. Kanchanjunga Conservation Area
iii. Blackbuck Conservation Area iv. Api Nampa Conservation Area
v. Gaurishankar Conservation Area
S. Conservation Area Estd Loaction Major Plants and
Animals
No Aeas year
Chilaune, Katus, Uttis
1. Annapurana 7629 2049 Kaski, Gobre salla, Bhojpatra,
Conversation Sq. B.S Lamjung, etc and Red Panda, Musk
Area km Mustang, deer, Snow leopard, Gray
Manag and wolf, Himalayan bear,
Mygdi Tibetan sheep Inpeyan
pheasant (Danphe),
Crimsom Horned
pheasant (Munal)
Blooming Science & Environment Book 8 295
2. Kanchanjunga 2035 2054. Taplejung Dhupi, Gobre salla etc.
and Red panda, Musk
Conservation sq. B.S. deer, Snow leopard,
Himalayan brown
Area km bear, Lynx, Gray wolf,
Assamese monkey,
Leopard cat, Danphe,
Munal, etc.
3. Manaslu 1663 2 0 5 5 Gorkha Birch, Fir, Pine, Dhupi,
Conversation sq. B.S. Gobre salla etc and Red
Area km panda, Musk deer snow
leopard, Lynx, Gray
wolf Assamese monkey,
Leopard cat, Danphe,
Munal, etc.
4. Api-Nampa 1903 2067 Darchula Uttis, Banjh, Gurans,
Conservation sq. B.S. Gobre salla, Khashru, etc
Area km and Red panda, Musk
deer, Snow leopard,
Clouded leopard,
Impeyan Pheasant,
Crimson pheasant, cheer
Pheasant,etc.
5. Gaurishankar 2179 2066 Dolkha, Khote sallo, Uttis,
Conservation sq. B.S Sindupalchowk Katus, Saur, Gobre sallo,
Area km and Laligurans, Bhojpatra,
Ramechhap Dhupi, Chiraito, Jatamasi,
Sunakhari, Padamchal,
Bishma, etc. and Red
panda, Musk deer, Snow
leopard, Pangolin, Gray
wolf, Assamese monkey,
clouded leopard,
Impeyan pheasant,
Crimson pheasant, etc.
6. Krishnasar 16.95 2065 Bardiya Black buck (Krishnasar)
conservation sq B.S Hyaena (Hundar), Asiatic
Area km Rock Phython ( Ajingar)
and Golden monitor
lizard (Sungohoro)
The major purpose of establishing national parks and wildlife reserve is to conserve
wild animals, birds and their natural surroundings and to conserve gene pool.
296 Blooming Science & Environment Book 8
The following steps should be taken to conserve wildlife.
1. Habitat Preservation
Preserving the habitat of wildlife helps in their conservation. Preventing
deforestation is an important method of habitat preservation. Setting up
national parks, creating wildlife sanctuaries, by setting aside permanent
protected areas where animals can live and breed in their natural habitat, is
another method. Planting new forests provide shelter and food for wildlife.
Protection of wild animals should be done. For this purpose, national parks and
wildlife sanctuaries should be set up.
In Nepal, there are a large number of wildlife sanctuaries set up by Government
of Nepal for the conservation of wildlife.
2. Hunting Regulations
Government regulations relating to hunting and their effective implementation,
is very important for wildlife conservation. The hunting of endangered species
is completely banned. In Nepal, though the hunting is banned, animals are
regularly killed as their skin, the bones fetch large amounts of money. Effective
implementation of such laws is, therefore, of extreme importance. Musk
Deer has been hunted for centuries. Its musk is used in perfumes and fetches
a lot of money in illegal trade. Therefore, proper laws and their effective
implementation for forbidding hunting should be enforced. Hunting and illegal
trade should be checked and should be made punishable.
3. People Awareness
To create an awareness among people about the importance of animals in
nature, publicity, such as postering, and in other communication media like
radio, television should be done.
Economic Importance
Naturalist conduct research and find new discoveries in the natural environment.
Country can earn foreign currency from medicinal herbs. Natural resources like
mountains, hills, forests, lakes, rivers attract tourists. Every year many tourists visit
Nepal to see natural beauty. So, it is essential to preserve our national resources from
economical point of view.
The skin of some animals like cow, buffalo, calf, crocodile and snakes are used for
making leather. The hide of such dead animals is made into fine leather which is used
for making clothes, shoes, belts, bags etc. The skin and bones of animals fetch large
amounts of money.
The tusks of male elephants provide the expensive ivory. It issued for making
decorative pieces.
Blooming Science & Environment Book 8 297
Main Points to Remember
1. The resources which are created by nature freely for human use are known as
natural resources.
2. Man also depends upon different natural resources available in the environment.
3. Human beings are completely dependent on natural resources for food, shelter
and medicine.
4. A national park is a separate reserved area for the conservation and management
of natural environment including wild flora and fauna.
5. Wildlife reserves is a separate area for protection and management of wildlife
and their habitat.
6. Hunting reserves are opened to hunt animals time to time. Dhorpatan hunting
reserve is only one hunting reserve of our country.
7. Plants which look beautiful are grown in gardens, parks and flower pots for
decoration are known as ornamental plants.
8. The local people conserve wildlife conservation areas.
9. Forest is the essential component of natural environment. Forest area is
decreased due to over population.
10. There are 844 species of birds 184 species of fish and 181 species of mammals
found in Nepal.
11. Zimbu, opium, harro, barro, sarpagandha etc. are medicinal plants.
12. The wildlife which are unable to adapt due to deforestation and other human
activities are called endagered species.
13. Kalij, luinche, deer, naur, snow leopard, saras, ghariyal are endangered birds
and animals.
PRO J ECTWORK
1. Collect different medicinal plants found in your locality and preserve them.
2. Take a chart paper and write all national parks, wildlife reserves, conservation
areas, their area in sq.km. and extended districts.
Exercise
1. Fill in the blanks.
a. There are ................... national parks in Nepal.
b. .................. is only one Hunting reserve.
c. The plant, soil, water are .................resources.
d. On the basis of ............. range, different types of fauna are available.
e. .................... is the largest national park of 3555 sq.km.
298 Blooming Science & Environment Book 8
2. Write ‘True’ or ‘False’ for the following statements.
a. All the creatures need same types of environment.
b. Man is the main cause for environmental imbalance.
c. Different fauna and flora of Nepal are endangered.
d. Sal is the medicinal plant.
e. Tiger is an aquatic animal.
3. Match the following.
Rhino national park
Rara Flora
Fauna Source of water
Green vegetation endangered animal
4. Answer these questions
(a) What is environment? Why is environmental balance necessary?
(b) What are natural resources? Classify them.
(c) How does man depend on natural resources?
(d) What is the inter-relationship between man and environment?
(e) Describe the role of forest in our ecosystem.
(f) What are called national parks? Name national parks of Nepal.
(g) What are the main causes of deforestation?
(h) What is a hunting reserve?
(i) List the attempts made to conserve wild life.
(j) Write the economic importance of national parks and conservation areas.
(k) Discuss the importance of medicinal herbs.
(l) What are called endangered species? Name 1 bird, 1 animal and 1 herb.
(m) Medicinal herbs are good sources of income, why?
(n) Discuss the applied activities for the conservation of wildlife.
5. Give the differences between National park and Reserve area
6. Write short note on
a. Conservation Areas b. Medicinal Herbs c. National Park
Blooming Science & Environment Book 8 299
Glossary
topsy-turvy : upside down
conceive : become pregnant
convention : custom based on general consent
persuade : cause somebody to do
swamp : soft wet land
bog : spongy ground
trash : worthless material
introduced : brought into use for the first time
monograph : detailed facts
decade : period of ten years
polygamy : custom of having more than one wife
abolish : put an end to
avail : take advantage of
transportation : carrying from one place to another
topography : features
haphazard : without plan
rare : uncommon
poach : take illegally
reverence : deep respect
dilapidated : ruined, wasted
renovate : make new again
costume : style of dress
indigenous : native to a country
300 Blooming Science & Environment Book 8
23Chapter Environmental Degradation
& Conservation
Learning Outcomes Estimated Periods: 16+4
On the completion of this unit, the students will be able to:
Describe environmental pollution (air, water, soil & sound ) and their effects.
Describe green house effect and effect of increase in temperature on
environment.
. Tell the causes and effects of acid rain.
Describe the ways of environmental conservation.
Introduce different disasters their cause and ways to reduce their effects.
Introduce and tell contribution of NTNC, IUCN, WWF, UNEP and ICIMOD
in nature conservation.
Natural resources are overused due to population growth. Excessive pressure
in natural resources cause environmental degradation. So, the problem of floods,
landslide and soil erosion occurs. Deforestation and depletion of habitat of wild birds
and animals are taking place. Over use of natural resources have created imbalance in
the environment. It disturbs the life of man, birds, animals and overall ecosystem.
The reduction in quality and quantity of any component of the environment generally
called environment degradation.
Environment degradation can be defined as any alteration in the composition or state
of the environment which directly or indirectly causes harm to us.
Blooming Science & Environment Book 8 301
Pollution
Physical, chemical and biological change in the natural qualities of air, water and soil
is called pollution. It affects the health of the common people and cultural heritage
also. The agents of pollution are called pollutants. It is found in the form of solid,
liquid and gas. Heat and noise are also a kind of pollution. It harms human beings,
animals, birds, forests, historical monuments and non-living components.
The air, water and land are getting polluted due to population growth. The problem
of environmental pollution is increasing day by day in Nepal. There are different
types of pollution. Some of the major types of pollution found in Nepal are as follows:
i) Air pollution ii) Water pollution
iii) Land pollution iv) Noise pollution
1. Air Pollution:
Air mixed with dust, smoke
and harmful bacteria is called
impure air. When the stench
of garbage mixes with air, it is
called air pollution. There are
gases, chemicals, dust particles
and other harmful gases in
polluted air. It causes harm to
men, animals, birds, vegetation
and many other cultural
heritage.
Air pollution can be defined as an undesirable change in our air, which directly
or indirectly causes harm to us.
2. Water Pollution:
The source and capacity of
water does not increase if
it is not well managed. The
garbage, drains and sewage
coming out of industries and
factories pollute the water
source. It is known as water
pollution. Harmful germs and
bacteria cause water pollution.
Water pollution can be defined as an undesirable change in water, which
302 Blooming Science & Environment Book 8
directly or indirectly cause harm to us.
It causes the scarcity of pure and clean drinking water. The water of Bagmati
and Bishnumati in Kathmandu has been excessively polluted. Similarly, the
historical pond of Patan, Bhaktapur and Janakpur are also facing the problems of
water pollution. The polluted river and tank water is of no use for any purpose.
3. Land/ Soil Pollution:
Generally, the deterioration in quality of land is known as land pollution. It
degrades the fertile upper crust of the earth.
Land pollution can be defined as an undesirable change in land, which directly
or indirectly causes harm to us.
The land pollution degrades quality of soil. The germs that protect the soil also
die due to the pollution in land. It causes decline in soil fertility. The land is a
valuable gift of nature. Its pollution causes imbalance in the environment.
Effects from soil pollution are as follows:
i) The bad smell spreads from the polluted land. It destroys the surrounding places.
ii) It destroys the fertility of soil.
iii) It spoils the beauty of the natural environment.
iv) Soil pollution also causes pollution to water resources.
v) Earthworms and micro-organisms die due to soil pollution. They improve
quality of soil.
4. Noise/ Sound Pollution:
The loud and unpleasant sound is
known as noise pollution. It causes
discomfort and harm to living beings.
Sound pollution can be defined as an
undesirable change in sound, which
directly or indirectly causes harm to
us.
Blooming Science & Environment Book 8 303
The loud sound affects the living creatures in keeping peaceful atmosphere.
There are several factors causing noise pollution.
The loud sound, produced by any sources, can be tolerated by man and animals.
It creates noise pollution in the environment.
Effects from noise pollution are as follows:
i) It is harmful to mind, body and health. It can also cause loss of sleep, heart
disease and other weakness.
ii) It may bring deafness to man.
iii) The hearing power declines by a loud noise.
iv) It affects the mental concentration which decreases the efficiency of man.
v) Noise is also said to cause visual disturbances.
Misuse of Pesticides
The proper use of pesticides is advantageous. But
the majority of farmers are illiterate. They are
ignorant about the methods of using, the quantity,
quality and time for the spray of pesticides. Thus
they do not make proper use of pesticides. The
pesticides and chemical liquids that are sprayed
in crops for killing the harmful pests also mix in
the soil. This makes water source polluted. The
polluted source of water naturally causes the
drinking water to get polluted. So, the health of
men, livestock, birds and other living beings is affected. Hence, pesticides should
not be used carelessly. It also destroys the useful insects of the soil. It results in the
decline of agricultural productivity. Thus, the use of poisonous medicines destroys
the environment. Therefore, farmers should learn about proper methods before the
use of BHC, DDT, Deldrin, Metacid and other such chemicals.
Industrialisation: Industrialisation refers to the process of setting up industries to
produce different products.
Greenhouse Effect
The greenhouse effect is a process by which thermal radiation from a planetary surface
is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions.
Since part of this re-radiation is back towards the surface, energy is transferred to the
surface and the lower atmosphere. As a result, the temperature there is higher than it
would be if direct heating by solar radiation were the only warming mechanism.
Solar radiation at the high frequencies of visible light passes through the atmosphere
to warm the planetary surface, which then emits this energy at the lower frequencies
304 Blooming Science & Environment Book 8
of infrared thermal radiation. Infrared radiation is absorbed by greenhouse gases,
which in turn re-radiate much of the energy to the surface and lower atmosphere.
The mechanism is named after the effect of solar radiation passing through glass and
warming a greenhouse, but the way it retains heat is fundamentally different as a
greenhouse works by reducing airflow, isolating the warm air inside the structure so
that heat is not lost by convection.
By their percentage contribution to the greenhouse effect on Earth the four major
gases are:
• water vapour, 36–70%
• carbon dioxide, 9–26%
• methane, 4–9%
• ozone, 3–7%
The major non-gas contributor to the Earth’s greenhouse effect, clouds, also absorb
and emit infrared radiation and thus have an effect on radiative properties of the
atmosphere.
Climate Change
Climate change is a significant and lasting change in the statistical distribution of
weather patterns over periods ranging from decades to millions of years. It may be a
change in average weather conditions. Climate change may be limited to a specific
region or may occur across the whole Earth.
The most general definition of climate change is a change in the statistical properties
of the climate system when considered over long periods of time, regardless of cause.
Accordingly, fluctuations over periods shorter than a few decades, , do not represent
climate change.
The term sometimes is used to refer specifically to climate change caused by human
activity, as opposed to changes in climate that may have resulted as part of Earth’s
natural processes.In this latter sense, used especially in the context of environmental
policy, the term climate change today is synonymous with anthropogenic global
warming. Global warming refers to surface temperature increases, while climate
change includes global warming and everything else that increasing greenhouse gas
amounts will affect.
Global Warming
Different vehicles and factories emit harmful gases like sulpherdioxide,
carbonmonoxide and chlorofluro carbon that make a layer which permits the
ultraviolet ray from the sun penetrate into the earth but they (rays) don’t escape from
the earth. Due to this, the temperature of the earth increases and animals and plants
are severely affected. This is called global warming.
Blooming Science & Environment Book 8 305
Acid Rain
Acid rain is a popular term referring to the deposition of wet (rain, snow, sleet, fog,
cloudwater, and dew) and dry (acidifying particles and gases) acidic components.
Distilled water, once carbon dioxide is removed, has a neutral pH of 7. Liquids with
a pH less than 7 are acidic, and those with a pH greater than 7 are alkaline. Clean
or unpolluted rain has a slightly acidic pH of over 5.7, because carbon dioxide and
water in the air react together to form carbonic acid, but unpolluted rain also contains
other chemicals. A common example is nitric acid produced by electric discharge in
the atmosphere such as lightning. Carbonic acid is formed by the reaction
H2O (l) + CO2 (g) H2CO3 (aq)
Carbonic acid then can ionize in water forming low concentrations of hydronium and
carbonate ions:
H2O (l) + H2CO3 (aq) HCO3− (aq) + H3O+ (aq)
Acid deposition as an environmental issue would include additional acids to H2CO3
Acid rain does not directly affect human health. The acid in the rainwater is too dilute
to have direct adverse effects. However, the particulates responsible for acid rain
(sulphure dioxide and nitrogen oxide) do have an adverse effect. Increased amounts
of fine particulate matter in the air do contribute to heart and lung problems including
asthma and bronchitis.
Effect of Acid Rain on Statues
Acid rain can also damage buildings and historic monuments, especially those made
of rocks such as limestone and marble containing large amounts of calcium carbonate.
Acids in the rain react with the calcium compounds in the stones to create gypsum,
which then flakes off.
Disaster Management
A disaster is a natural or man-made hazard that has come to fruition, resulting in an
event of substantial extent causing significant physical damage or destruction, loss
of life, or drastic change to the environment. A disaster can be ostensively defined as
any tragic event with great loss stemming from events such as earthquakes, floods,
catastrophic accidents, fires, or explosions.
The local communities at the time of disaster or before the disaster make groups for
helping the people from suffering during the disaster. These groups include First
Aid group, Health group, Food and Welfare group etc. They all are well trained
by some local community members. All the groups are sent for helping any other
local community that is suffering from a disaster. They also ask people to move
from the area affected from disaster to some other safe regions. They are given
306 Blooming Science & Environment Book 8
shelter and every possible facilities by those local management communities. Today,
Government is also making effort to provide good facilities during the disaster. In
Nepal, in the rural areas, the community (group of families) are choosing a leader
and developing their Disaster management skills to protect themselves and other
local communities as well.
Methods of Conservation and Promotion of the Environment
Environment is our common property. We know that there are different components
of environment. These components should be managed properly for the conservation
and promotion of the environment. It is our responsibility to protect and conserve
it. Different activities such as public awareness programmes, afforestation,
forest conservation, environmental sanitation, publicity campaign, conservation
and protection of cultural heritage, etc. should be implemented. Environmental
conservation can be defined as all those activities which are conducted with the aim
of preserving the various components of the environment in good state for our future
generation.
Some of the methods recommended for the conservation and protection of the
environment are as follows:
ENVIRONMENT CONSERVATION
Conserving Existing Controlling Environment
Natural Resources Unfriendly Activities
• Conserving of Flora and Fauna • Managing Population
• Conserving Water Resources • Controlling Pollution
• Conserving Mineral Resources • Promoting Environment
• Conserving soil
• Conserving Cultural Heritage Sanitation
Major Activities on Environment Conservation are described below:
1) Conservation of Forest
The Ministry of forest and Land Conservation has launched various programmes
to conserve the forest. Afforestation programme in various places, community
forestry programme are carried. Local people have also active participation
in forest conservation. Similarly, matters related to forest conservation are
integrated in school and college curriculum. Various awareness programmes
are also launched.
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2) Soil Conservation
Soil conservation is also the objective of environment conservation. The
ministry of forest and land conservation and ministry of agriculture are working
to conserve the soil. To conserve the soil, use of chemical fertilizer should
be reduced, landslide and soil erosion should be checked. For that various
awareness programmes are launched. Even in the curriculum of school and
college these matters are integrated.
3) Management of Wastage
Improper disposal of solid and liquid wastages pollutes the environment. Various
organizations, local bodies such as VDCs, Municipalities are contributing for
its proper management. Construction of public laterine also helps to manage
the wastage.
4) Control of the Pollutants
Waste water, dust particles, garbage, harmful smoke released from the factories
and industries are the agents to pollute the environment. It is, therefore,
essential to control these pollutants to conserve the environment. Awareness
programmes for their reduction are being launched.
5) Public Awareness
Unless the people are not conscious about the harmful consequences of
environmental degradation, they cannot conserve it. Realizing this very fact,
National and International agencies are paying attention to public awareness.
Even, through the process of education in school and college, people are made
aware of environment issues raised at the global level.
6) Watershed Management
Watershed plays a vital role for the balance of ecological process. It is the basis
for the survival of the aquatic animals and plants. Besides this, it is equally
important for agriculture, as well as for industrialization process. It is also
the source of drinking water. It is equally important for tourism development.
Hence, it needs to be managed in a sustainable basis which helps all the living
beings including human beings for regular supply of water. For the proper
management of watersheds, plantation of trees in its surrounding should be
done at the same time it should be protected from pollutants.
International Organizations and Agencies
The international organization and agencies have significant role in conducting
various programmes of managing the population and consvering the environment.
These organizations and agencies have great role in formulation of policies and
308 Blooming Science & Environment Book 8
programmes in the field of environment conservation and population management.
They also have several programmes in villages. The international organizations
and agencies such as United Nations Population Fund ( UNFPA), United Nations
International Children’s Emergency Fund ( UNICEF ), World Food and Agriculture
Organization ( FAO ), United Nations Environment Programmes ( UNEP ), IUCN
– The World Conservation Union, World Wide Fund for Nature ( WWF ), etc. are
helping to run the population and environmental education programmes. These
international agencies are providing economic and technical support to conduct the
programmes for the management of population and conversation and promotion of
the environment.
United Nations Environment Programme (UNEP)
The UNO had organized a conference related to man and
environment in Stockhome of Sweden in June, 1972. This
conference strengthened the concept that man has the right of
surviving in healthy environment and it should be preserved
for the future generation. June 5th which was the first day
of the conference is celebrated as ‘World Environment Day’
every year.
At the end of 1972, the General Assembly of the UNO established the ‘United Nations
Environment Programme’ in Nairobi of Kenya, as its headquarter. The regional
office is situated at Bangkok, the capital city of Thailand for Asia. 58 countries from
5 continents are represented in the ‘Superme Council.’ The governments of different
countries, scientists, trader’s group, non-governmental organizations, women and
young groups have been participating in its various programmes. UNEP pays special
attention to make the world development activities healthy and long lasting from
environment point of view. It also plays a vital role as co-ordinator to the various
environmental programmes conducted by the different agencies of the United
Nations.
IUCN - The World Conservation Union
(a) Introduction: It is a non-governmental
organization established in 1948. The The World Conservation Union
International Union for Conservation of
Nature and Natural Resources is an INGO. Recently, it has been named IUCN
- World Conservation Union. It is called only IUCN in short. The head office
is in the city of Gland in Switzerland. It is an independent agency formed by
nations, governmental agencies and non-government organizations, scientists
and environment conservationists. It has got 913 members from 138 countries
since the month of Paush 2054 B.S. Nepal has got its membership in 1973.
Blooming Science & Environment Book 8 309
The National Parks and Wildlife Conservation Department, Nepal Trust for
Nature Conservation Fund, the World Conservation Union, Nepal Environment
Journalists Group, Nepal Resource Conservation Society, Nepal Heritage
Association, Environment and Culture Conservation Association, Environment
Conservation Camp have got the membership of IUCN. Among these
members, National Parks and Wildlife Conservation Department represents the
government. Many NGOs have expressed their interest to be the membership
of IUCN.
(b) Objectives: The major objectives of the World Conservation Union (IUCN)
are as follows:
i. To protect the natural solidarity of nature and its diversities,
ii. To conserve natural resources and utilize them on a sustainable basis,
iii. To inspire, encourage and co-ordinate the different countries, societies
and organizations to achieve its fixed target.
The IUCN is active to establish close relationship between development and
environment. It is also trying to enhance the standard of living of all the people of
the world. The IUCN Nepal is committed to fulfill the above target in the context of
Nepal.
(c) Programmes: The major programmes of the IUCN are to encourage, to inspire
and to cooperate the international community for protection and conservation
of bio-diversity and nature for the sustainable utilization of natural resources
without affecting the environment. IUCN is involved in the study of the state
of environment and policy formulation. It has given emphasis to conduct the
programmes related to environment at the local and regional basis. It has the
aim to support the long term development through environmental conservation.
In this context, this Union has its network throughout the world for the
environmental related activities. This union communicates the technology,
research work, conceptual framework, etc. developed at any places throughout
the world.
Some of the programmes of IUCN are as follows:
1. It helps the government and non-government organizations to develop training
packages, source books and other materials.
2. It identifies the environment impacts of development activities and to develop
guidelines and implement these to minimize the effects.
3. It protects and conserves the cultural heritage and natural heritage and
resources.
4. It takes initiation to conserve the bio-diversity,
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5. It leads local agencies to develop environmental code of conduct according to
the need of national and international laws.
(d) Important functions of IUCN in Nepal: The national conservation work
policy execution project was carried from 1989 to 1996 in Nepal. The project
was conducted with the joint effort of National Planning Commission of
Nepal government and IUCN with the financial and technical support of
Swiss Government. Important functions of this project were the environmental
Education, Environmental Effect Study, Environmental Plan, Environmental
Law, Conservation of Natural Resources and Bio-Diversity, etc.
IUCN provides economic and technical support to more than 60 non-
governmental agencies throughout the country to implement natural
resources conservation activities. It also leads to the government of Nepal to
organize ‘Environment Conservation Council’ and formulate and implement
environmental law and policy.
As a result of the successful implementation and fruitful achievements of
National Conservation Policy Project, the IUCN was established in Nepal in
February, 1995 as a National office. The expenditure of technical works of
this office is mainly financed by the Swiss Development Federation. Besides,
this organization has been given financial supports from different national
and international educational institutions, Conservation of bio-diversity,
study of environmental impact, environmental law, environmental planning,
conservation of natural and cultural heritage, conservation of wetland, etc. in
Nepal under National Conservation Policy Project, it is also conducting various
environmental research programmes.
World Wildlife Fund for Nature (WWF)
(a) Introduction: WWF is an international non-governmental
organization for the conservation of nature. It was
established in 1961. It was called the ‘World Wildlife Fund’
during its establishment but since 1986, it is called World
Wildlife Fund for Nature (WWF). But in North America and
Canada, it still retains its name as World Wildlife Fund. Its
head quarter is in Switzerland. At present, 31 institutions,
national organizations and 22 offices in the five continents
of the whole world in operation using its name and seal.
WWF is an active work-oriented organization. It has been endeavoring to conserve
rare living creatures and natural resources on the earth. It has a close relationship
with the ‘World Conservation Union, too.’ The programme of this fund is not limited
to the conservation of rare species only. It has emphasised the conservation of the
environment and world natural habitat in totality.
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(b) Objectives of the WWF: The major objectives of the WWF are as follows:
1. To protect and conserve the genepool, races of the organisms and the
diversity of geo-spatial system.
2. To ensure sustainable utilization and development of renewal natural
resources for present and future generation, and,
3. To organize various programmes to reduce consumption of natural resources
and energy producing toxic waste products and polluting the environment.
(c) Programmes: The WWF has already conducted more than 5000 conservation
projects related to nature conservation in about 130 countries. This fund
has helped in the protection and conservation of many rare wild animals
and vegetation of the world from getting disappeared. This fund has been
cooperating in conducting the programmes such as taking care of water
resources, protection of endangered plants and wild animals, checking of
illegal trading of endangered animals and plants, etc. in Nepal. This fund has
encouraged the different countries to establish Ministry for Environment and
Nature Conservation. The nature’s conservation and environmental issues are
getting important place in school curriculum, radio and T.V. programmes.
United Nations Development Programme (UNDP)
UNDP has provided technical and financial
assistance in all the fields of development to more
than 150 developing countries of the world. It has
its head office at New York. It has a country office
in Nepal represented by a permanent representative.
It helps in the development of environmental health,
land protection, rehabilitation of grazing field,
forest, water and the conservation of wild animals
and forest products, etc.
The tropical forest is the chief and important natural source of food, shelter, medicine
to increasing number of people. Active people’s participation is necessary for its
protection and conservation. The social forest project encourages the afforestation in
Thailand through providing right on land to farmers. The community forest project
in Norway which published final report on our common future in 1987.
The world concerned environmental issues were recognized in it by collecting
wide general statement of 14 cosmopolitan cities of the world. The related things,
challenges and efforts were stated in three parts of the report. Now, our common
future has been recognized as an important measure for sustainable development
all over the world. This report has been translated into twenty five languages of the
world.
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The main objective of this centre is to extend worldwide discussion, to awaken and
extension for the long lasting development. Besides, it performs the work of an
exchange centre of opinions and activities of various areas to integrate the activities
for obtaining common goal.
The centre publishes Quarterly Bruntland Bulletin to acknowledge the reactions of the
people and the activities regarding the Common Future Report. Thus, this centre can be
accepted as an important organization to bring about awareness for world environment.
International Centre for Integrated Mountain Development (ICIMOD)
ICIMOD is a non-governmental
organization established in 1983
with the aid of UNESCO. The
major objective of this centre is
to get substantial development
of natural resources,
development of hilly region and the community development and reformation
through adopting essential modern development technology by formulating proper
policy and programmes. ICIMOD has made Hindu-Kush region as its working field.
ICIMOD works to solve the environmental problems of Hindukush region through
the experience and study of other hilly regions.
Objectives of ICIMOD
1. To exchange knowledge of policy, programmes and projects for integrated
development of hilly region and practical experience among nations.
2. To include technology and process of current knowledge, practical training
programme to institutional development for integrated development of hilly
region.
3. To increase research capacity to fight with major problems of hilly conditions
and development.
4. To strengthen the international exchange of specialists for the development
and conservation of hilly region.
Activities of ICIMOD
ICIMOD has completed various programmes of environmental conservation. It
has organized a conference in 1985 with joint collaboration of hilly development,
problems and opportunities and King Mahendra Trust for Nature Conservation along
with the World Conservation Council in 1983. This centre has studied and made
a research work of district level energy project and management, management of
mountainous watershed area, employment opportunity in hilly region, hilly agriculture
and geneology, central point of soil erosion in Hindukush region, horticulture, bee-
farming and hill disasters, etc.
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Nepal Trust for Nature Conservation (NTNC)
This is non-governmental organization. It was established in 2039 B.S. It has conducted
various projects of development including environmental conservation also. This
organization has conducted the project of Annapurna Conservation Region for natural
resource conservation and management. Associated with environmental agencies of
Nepal, this organization conducts national, international seminars and research studies.
Main Points to Remember
1. Pollution can be defined as an undesirable change in air, water and land resources
caused mainly as a result of human activities and affecting human being adversely.
2. The greenhouse effect is a process by which thermal radiation from a planetary
surface is absorbed by atmosphere greenhouse gases.
3. Climate change is a significant and lasting change in the statistical distribution
of weather patterns over periods ranging from decades to millions of year.
4. The process of increasing temperature of earth and animals and plants are
severely affected is called global warming.
5. Acid rain means deposition of rain, snow, fog etc. and dry acidic component.Acid
rain means rain of carbonic acid which has adverse effects to environment.
6. Environmental conservation can be defined as all those activities which are
conducted with the aim of preserving the various components of the environment
in good state for our future generation.
7. Many international agencies are trying to manage the population growth and
conserve the environment.
8. The main function of IUCN is to encourage, motivate and help the world
community to conserve the nature and utilize the natural resources.
9. UNEP gives special attention to make the world’s development activities
healthy and sustainable from the environment point of view.
10. UNEP - established in 1972 - represented by 58 countries - concept is ‘everybody
has right to live in the healthy environment’ - main programme to make the world
development activities healthy and sustainable. Head office - Nairobi, Kenya.
11. IUCN - established in 1948 - main objective is to maintain the earth’s integrity -
programme is to study environmental status and make sustainable development.
12. WWF - established in 1964 - main objective is to control indiscriminate use of
sources and energy - programme is to conduct projects for the conservation of
nature. Head office - Switzerland.
13. UNDP - head office New York - technical and financial help in development
work, environmental health - helps Nepal in forest project.
14. NTNC - established in 2039 B.S. - main function conservation of environment.
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PRO J ECTWORK
Make different groups of students in your class. write a script of drama related
to conservation activities and play it in your community if possible, other wise
perform this in your school with the help of your teacher.
Exercise
1. Fill in the blanks
(a) Heat and .................are also a kind of pollution.
(b) There is ............... acid in acid rain.
(c) WWF was set up in ..................
(d) IUCN is working in the field of .............
(e) June .................is celebrated as ‘World Environment Day’ every year.
2. Write ‘True’ or ‘False’ for the following statements.
a. Sulphur dioxide is a green house gas.
b. Due to global warming, there is decrease of earth temperature.
c. IUCN was established in 1948 AD.
d. Nepal has got membership of UNEP in 1973 AD.
e. NTNC is a non-governmental organization.
3. Match the followings.
WWF World Environment Day
Methane Smoke, dust and chemical
Pollution Switzerland
5th June World wildlife fund
IUCN Green house gas
4. Write the full form of.
(a) NTNC (b) IUCN (c) WWF (d) UNEP (e) ICIMOD
5. Answer the following questions.
(a) What is environmental degradation?
(b) What is pollution? List the types of pollution
(c) What is green house effect? Write few green house gases.
(d) What are the impacts of climate change in environment?
(e) What is global warming?
(f) Define acid rain.
(g) List the measures of environmental conservation.
Blooming Science & Environment Book 8 315
(h) What is conservation of environment?
(i) What is meant by risk minimization?
(j) List any five international agencies work for conservation of environment.
(k) Write short description on NTNC.
(l) List any 5 measures to control pollution.
(m) What are natural disasters?
(n) List the major activities done for conservation and promotion of environment.
6. Write short notes on.
a. Global warming b. Natural Disasters c. Acid rain d. ICIMOD
7. Write the objectives of
a. NTNC b. IUCN c. WWF
d. UNEP e. ICIMOD
Glossary
Abbreviation : short form
Implement : put into effect, carry out, achieve
Integrated : combined with something
Extension : increase in size
Slogan : Word or phrase used as a motto
Conference : meeting
Propound : formulate
Participate : involve
Sustainable : long lasting
Wetland : low lying wet land
Affiliate : enter into association
Heredity : transfer of physical and mental characters from parents to offsprings
Multinational : of many nations
Upgrade : improve
At the outset : in the beginning
Livestock : animals kept for use or profit
Treaty : agreement; formal agreement signed between
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Chapter
24 Sustainable Development
and Biodiversity
Learning Outcomes Estimated Periods: 8+2
After the completion of this unit, the students will be able to:
define the importance of biodiversity.
describe the major principle of sustainable development.
describe global efforts on sustainable development.
Concept of Biodiversity
Introduction
Earth is the habitat of large number of living beings including plants, animals,
birds and micro level organisms. Diversity is found among these organisms. Such
differences or diversities in ecosystem are considered as biodiversity. It includes
ecosystem, genetic and species diversity. Biodiversity of a location refers to existing
organisms, species, living beings and ecosystem per unit of land. It refers to a
total number of living organisms of the earth and their diversities. In this regard,
biodiversity can be defined as variety and variability of all living organisms and the
ecological complexes in a given region (habitat).
Biodiversity can be classified into three levels: i.e. species diversity, genetic
diversity and ecosystem diversity. Different species of plants and animals such as
man, elephant, bird, maize, pulse, potato, species of bacteria and virus are included
in species diversity. There is a numerical counting of species. Ecosystem provides
the habitat for the living organisms. Living beings spend their lives according to
the capacity of adaptation. Biodiversity is occurred by the structure of ecosystem.
Growth, survival and development of the organisms are controlled by genes. Living
beings have their own heredity qualities because of which they can adjust in their
own existing environment.
Biodiversity has the variation according to geographical region. Some living beings
are found on land, some in the water and the other in the atmosphere. Similarly,
some plants are found in lithosphere and some are in the hydrosphere. Biodiversity
has been maintained because living beings can adjust themselves according to the
geographical conditions. There is a special relation among the living organisms. If
Blooming Science & Environment Book 8 317
one is disturbed, the whole structure of living beings can be affected. For example, if
deforestation takes place, the system of vegetation, plants, wildlife and other living
beings will be adversely affected.
Biologists most often define biodiversity as “the totality of genes, species and
ecosystems of a region.”
The division of biodiversity can be shown in the following chart:
Classification of Biodiversity
Species Diversity Genetic Diversity Ecosystem Diversity
• richness in variety • richness in variety • richness in variety
and variability of and variability of and frequency of
organisms between organisms within distinct ecosystem
the species. the single species. including the
variation in habitats
• Leopard, elephant, • clouded leopard,
tiger, etc. snow leopard, • grass ecosystem
common leopard. • forest ecosystem
• agricultural • cropland ecosystem,
vegetation
etc.
• vegetation
• other living beings
(i) Ecosystem Diversity
Ecosystem diversity maintains the diversity of a place at the level of ecosystems.
It refers to the variety of habitat types and ecosystem processes extending over
a given region. Ecosystem diversity can be defined as:
“The variety and frequency of distinct ecosystems including the variability of
habitats, biotic communities and ecological processes in the biosphere.”
Ecosystem diversity encompasses the broad differences between ecosystem
types and diversity of habitat and ecological process occurring within each
ecosystem type. There are glaciers in Mountain region. Similarly, lakes,
ponds, cool places and wetlands in various places. There are small and large
ecosystems in the various places containing land and water ecosystems. The
wetland ecosystem has more significance for the growth and conservation of
biodiversity.
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(ii) Genetic Diversity
Among the vegetations, plants and animals living on the earth, there are some
differences. It is due to the genes within nucleus of cells found in the body.
Genes transfer hereditary characters of all living beings in their offspring.
Thus, inherited characters of living beings help to maintain biodiversity.
Genetic diversity is a level of biodiversity that refers to the total number of
genetic characteristics in the genetic makeup of a species. Genetic diversity
occurs within and between population of species as well as between species.
It covers genetic variation between distinct populations of same species.
Chromosomes, genes and DNA determine the uniqueness of each individual
and each species. Genetic diversity can be measured within a variety of DNA
and other techniques. Hence, genetic diversity can be defined as: the range of
genetic variation and variability found within the population of single species
and between the species in a given region (habitat).
(iii) Species Diversity
Nepal has covered 0.01% of the land in the earth. 72% area covered by water
is not included. If it is included the percent becomes 0.03%. It has different
land topography and climate. There has been created differences in ecosystem
because of it. Hill ecosystem has much diversity while comparing Mountain
and Terai. It has provided appropriate habitat to the plants and animals. In this
regard, Nepal is rich in species diversity.
Species diversity refers to the variety of species within a specific ecological
area. A species can be defined as a group of similar organisms that reproduce by
inter breeding within the group. Reproduction takes place within the members
of same species. Aspects of species diversity can be measured in a number of
ways. Most of these can be classified into three types: species richness, species
abundance and species taxonomic or phylogenetic diversity.
The status of species diversity of Nepal can be shown in the following table:
Plant Group Number of Plant Species Animal Group Number of Animal Species
Gymnosperm World Nepal Percent Mammals World Nepal Percent
Angiosperm Aves
Mosses 529 28 5.1 Reptile 4,000 181 4.5
Lichen Amphibian
Algae 2,20,000 5856 2.7 Fish 9,040 852 9.3
Fungi Butterfly
Bryophytes 380 Spiders 6,300 100 1.6
Pteridophytes
2,000 465 23.25 4,184 43 1.0
26,000 687 2.6 18,150 182 1.0
69,000 1,822 2.6 24,615 640 2.6
16,600 853 5.1 73,400 144 0.2
11,300 380 3.4
(Status of Species Diversity in Nepal, 2002 A.D.)
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Status of Animals and Birds in Nepal, 2002 A.D.
Animals, birds and Species of the Species of the Percent of Nepal
other living beings world Nepal
Insects 9,00,000 4,438 4.48
Butterfly 24,615 640 2.6
Spider 73,400 144 0.2
Fish 18,150 182 1.0
Amphibians 4,184 43 1.0
Reptiles 6,500 100 1.53
Aves (Birds) 9,881 852 8.6
Mammals 4,327 181 4.2
Importance of Biodiversity
At the ecosystem level, biodiversity provides the conditions and drives the processes
that sustain the global economy and our very survival as a species. The benefits and
services provided by biodiversity are described below:
(a) Agriculture products: The crops like paddy, wheat, maize, barley etc. are the
main foods of people. The source of these foods is the agricultural biodiversity.
In the ancient time, people brought useful species from forest and cultivated
to produce food for them then they selected best seeds to get high yield. These
processes contributed in the development of best agricultural crops, which are
the sources of food for people.
(b) Animal products: Animals are the sources of milk, meat, eggs, labour, and
other raw materials. Fish is another source of food. Birds are the beauty of
nature; they can be used for food and for other purposes. Dogs are pet animals.
Some medicines are made by using some animal’s products. People can conduct
animal farming to produce more production. Thus, all of the animal products
are the products of biodiversity.
(c) Plant products: Plants are the sources of food. Flowers and raw materials are
either obtained from forests or from agricultural land. Industries use leaves,
barks, fruits and materials for the production of other useful materials for the
production of other useful materials. Several species of mushrooms, medicinal
herbs, fruits, vegetables and plant products are collected and marketed. Plants
have the economic value in improvement of living standard of the people.
(d) Improvement of breeds: Animals and plants are used for breeding to produce
new varieties. It is for improving their production and quality. Wild animals,
birds, and other living beings are valuable sources that can be used for breeding.
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This breeding can help to improve the quality of the established domesticates,
they can be crossed to generate new varieties in the world. These improved
varieties / hybrids produce high yield of excellent quality.
(e) Conservation of soil: Land is one of the important natural resources. Soil
erosion deteriorates the quality of land. Vegetation is the basic ground that
protects the land. The vegetation and plants conserve moisture of the land.
Their roots contribute to keep together the particles of soil.
(f) Conservation of watersheds: The vegetation and plants contribute in
conservation of sources of water. Plants absorb water and help to remain in
soil. The plants also speed down the evaporation process. Thus, there is close
relationship among the biodiversity, water sources and watershed.
(g) Natural beauty: Nature is full of biodiversity. The plants and animals in the
nature have their own habitat and life styles. There is diversity of plants and
animals with the diversity of geographical structure. The diversity of plants
and animals keep the beauty of nature. Thus, biodiversity has contributed to
make the most valuable natural scene.
(h) Income generation: Yet biodiversity also has great importance as a direct source
of income and economic development. One example is ‘bio – prospecting’
(the search for previously unknown biotic products of specific utility, such
as natural pesticides, anti- fungal toxins and ‘oil – eating’ enzymes). Proper
way of preservation and commercialization of biological resources helps to
promote the scope of income generation.
(i) Development of tourism: The places in and around the Mountain, Hill and
Terai region have their own natural environment. There are different species
of plants, flowers, animals, birds, insects etc. in these places. The richness and
abundance of biodiversity have maintained natural beauty in various places of
the country. These natural beauties in different parts of the country may promote
the flow of tourists and eventually it may provide background to development
process of tourism sector. After all, the development of eco- tourism helps the
local people to improve their standard of living.
(j) Function of natural ecosystem: Biodiversity plays a significant role in the
functioning of natural ecosystem. Different species of living organisms and non
– living components of the environment of the given habitats are its inseparable
parts. Hence, biodiversity contributes to regulate the natural process like water
cycle, food cycle, flow of energy, recycling of carbon, nitrogen, oxygen and
other ecological processes and functions. Besides this, it also helps to maintain
the balance in temperature, precipitation, moisture, productivity of soil, etc.
therefore, biodiversity has a significant role in the human life system and
natural ecosystem.
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(k) Study and research: Innovative knowledge and information are the basic
aspects for the exploration and enrichment of biodiversity. Therefore, it is
essential to conduct research and study on different aspects of biodiversity for
the economic and social development of human kind. The knowledge and skills
acquired from the research and study should be utilized for the preservation
and promotion of species of living organisms and their habitats. The research
and study in biodiversity can be a great contribution for the welfare of all the
creatures including human beings.
Sustainable Development
Sustainable development is development that meets the needs of the present without
compromising the ability of future generations to meet their own needs. It contains
within it two key concepts:
• the concept of ‘needs’, in particular the essential needs of the world’s poor, to
which overriding priority should be given; and
• the idea of limitations imposed by the state of technology and social organization
on the environment’s ability to meet present and future needs
Sustainable development (SD) is a pattern of resource use, that aims to meet human
needs while preserving the environment so that these needs can be met not only in
the present, but also for generations to come. The term was used by the Brundtland
Commission which coined what has become the most often-quoted definition of
sustainable development as development that “meets the needs of the present without
compromising the ability of future generations to meet their own needs.”
Sustainable development ties together concern for the carrying capacity of
natural systems with the social challenges facing humanity. As early as the 1970s
“sustainability” was employed to describe an economy “in equilibrium with basic
ecological support systems.” Ecologists have pointed to The Limits to Growth, and
presented the alternative of a “steady state economy” in order to address environmental
concerns.
Objectives and Outputs
The primary objective of the assessment is to create a greater global understanding
of the extent to which decentralisation can make a positive difference in the quality
of lives of individuals and their communities. More specifically, it is expected that
the country level assessment will result in a better understanding of the country’s
experience in, and a clearer vision of future decentralized governance in the country.
Specific objectives are therefore as follows:
1) To understand the extent to which decentralised governance has increased the
effectiveness and the capacities of lower levels of governance.
322 Blooming Science & Environment Book 8
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