Biodiversity and Environment

There are many kinds of organisms on Earth, with different habits, living in different habitats. Animals and plants of water, desert, cold mountains and hot, wet forests have very different body structures and abilities. And even individuals of the same species differ from each other: in one field of maize, the plants differ in height, the thickness of the stem, the number and length of the leaves, and the position and number of the cobs.

The variety of living things, with their different structures and abilities, living in different environments, is called biodiversity (biological diversity). It tells us how rich the Earth is in kinds of living things: its species richness.

At the Earth Summit held in Rio de Janeiro, Brazil, in 1992, the world’s countries signed the Convention on Biological Diversity (CBD). It defines biodiversity as the variety among living organisms from all sources, on land, in the sea and in other waters, and the ecosystems they are part of; this includes diversity within species, between species and of ecosystems. In short: the variety of life at every level, from genes to species to whole ecosystems.

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Types of biodiversity

Living things are plants and animals (and microorganisms), so biodiversity is often described simply as the diversity of plants, called floral diversity (flora), and the diversity of animals, called faunal diversity (fauna). All the plants growing in and around a pond are its flora; the fish, frogs, insects and birds in and near the water are its fauna.

Scientists also divide biodiversity into three levels:

1. genetic diversity
2. species diversity
3. ecosystem diversity

(a) Genetic diversity

Genetic diversity is the variety among individuals of the same species, caused by differences in their genes. Different species obviously differ (crows from cuckoos, tigers from lions). But even within one species there are many differences. All humans today belong to one species, Homo sapiens, yet we differ in the color and type of our hair, skin and eyes, our height, the shape of our eyelids, eyebrows and nose, and how much body hair we have.

Nepal’s farmers have grown thousands of varieties of rice, each suited to its own altitude, soil and climate; that is genetic diversity too. It matters: if a new disease attacks one variety, others may resist it.

(b) Species diversity

Species diversity is the number and kinds of species living in a particular place. An ecosystem has producers, herbivores, omnivores, carnivores and decomposers, and each of these groups has many species. Nepal alone has dozens of species of frogs and toads, each with its own features, and hundreds of kinds of fish in its rivers.

(c) Ecosystem diversity

Ecosystems are of two main types, aquatic (water) and terrestrial (land), with many sub-types depending on the climate: the land ecosystem of a tropical forest is very different from that of an alpine meadow, and so are their producers, herbivores, omnivores, carnivores and decomposers. Where two ecosystems meet, such as a forest beside a river, their organisms mix and interact, which makes the whole even more complex.

The variety of ecosystems, which differ in their physical conditions (air, water, minerals, temperature, light) and in the local and migrating organisms that live in them, is called ecosystem diversity.

Importance of biodiversity

The physical and living environment of a place stays in balance only if it is rich in biodiversity. In a balanced, species-rich environment, organisms can more easily find habitat, food and partners to breed with. That is why biodiversity matters to every one of us:

• a.It provides the food and livelihood of every organism, including us.
• b.It keeps the environment in balance and increases the productivity of ecosystems.
• c.It allows the sustainable use of biological resources: food, timber, fiber, medicine.
• d.It helps conserve the environment and supports sustainable development.
• e.It attracts ecotourism and strengthens the nation’s economy.
• f.It helps living things adapt to hard conditions, such as the effects of climate change: the more varied the life, the more likely some of it survives a change.

Present status of biodiversity in Nepal

Nepal covers only about 0.1 % of the world’s land, yet it is extremely rich in biodiversity. The main reason is its huge range of altitude: from about 59 m above sea level at Kechana Kalan in Jhapa to 8,849 m at the top of Sagarmatha (Mount Everest), within about 200 km from south to north. That gives Nepal every climate from tropical to arctic-like. Add fertile soils and plenty of rain from the summer monsoon (and some winter rain), and you get a great many kinds of microbes, fungi, plants, worms, insects, fish, amphibians, reptiles, birds and mammals.

Nepal is often ranked about 25th–27th in the world, about 10th–11th in Asia, and 2nd in South Asia for biodiversity. It has about 3.2 % of the world’s known plant species and 1.1 % of its animal species. It has 118 types of ecosystem and 35 types of forest.

Some rare plants and animals are found only in Nepal, or are among Nepal’s great treasures:

• The spiny babbler (Turdoides nipalensis), a brown bird of the scrub of the middle hills, is found nowhere else in the world: Nepal’s only endemic bird.
• The one-horned rhinoceros and the Bengal tiger of the Terai, and the very rare wild yak of the high Himalaya.
• About 32 species of rhododendron (gurans), including the national flower, lali gurans.
• Marsi rice of Jumla, a native red rice that grows at about 3,000 m (Chhumchaur, about 3,050 m), among the highest places in the world where rice is grown.

Table 4.1 Some important flora of Nepal

Plant group	Species in the world	In Nepal	Nepal’s share
Lichens	more than 17,000	850	5 %
Algae	56,579	1,001	1.77 %
Fungi	98,998	2,467	2.49 %
Bryophytes (mosses and liverworts)	16,236	1,213	7.47 %
Pteridophytes (ferns and their relatives)	12,000	580	4.83 %
Gymnosperms (pines and other conifers)	1,021	41	4.02 %
Angiosperms (flowering plants)	369,400	6,973	1.89 %

Table 4.2 Some important fauna of Nepal

Animal group	Species in the world	In Nepal	Nepal’s share
Mammals	more than 4,765	185	3.88 %
Birds	9,799	886	9.04 %
Reptiles	more than 7,870	78	0.99 %
Amphibians	more than 4,780	118	2.47 %
Freshwater fish	about 18,000	187	1.04 %
Butterflies	17,500	651	3.72 %
Spiders	39,490	175	0.44 %

Causes of biodiversity degradation

All over the world, ecosystems and biodiversity are being damaged by natural disasters and, much more, by careless human activities. Unplanned growth of towns, industries, mining of rock and minerals, construction and farming are causing forests to be cut (deforestation), soil to be washed away (erosion) and land to dry out into desert (desertification), which affects the climate and all wildlife. Because of this, many wild species are close to extinction, and some are already gone. In Nepal the snow leopard is threatened, and the pygmy hog, the world’s smallest wild pig, has not been seen in Nepal’s wild for decades: it survives only in a few grasslands of Assam, India.

The decline in the number and kinds of plants and wild animals, because natural disasters and human activities disturb their lives, is called biodiversity degradation (loss of biodiversity). Its main causes:

• a.Overgrazing in natural forests damages seeds and seedlings, slows the growth of new plants, and in the end the forest declines.
• b.Chemical pollution from industries harms the biodiversity around them.
• c.Careless mining and blasting of rock and minerals cause noise, landslides and soil erosion, which harm plants and wildlife.
• d.Building roads, houses, dams and bridges without proper planning destroys the habitats of many wild animals.
• e.Collecting too much fodder and firewood leads to deforestation and dries up sources of water.
• f.Clearing forest for farmland and houses for a growing population reduces the forest area and its valuable species.
• g.Forest fires kill many wild animals and plants.
• h.Floods and landslides destroy many plants and animals.
• i.Global warming, from climate change, is changing the homes and lives of many plants and animals.
• j.Poaching (illegal hunting) and illegal trade in wild animals and their body parts reduce their numbers.
• k.Invasive plants, brought in from other countries, spread fast and push out the native plants. In Nepal, banmara (several weeds from the Americas, such as Ageratina and the climbing Mikania, which smothers trees in Chitwan) crowds out plants on land, and water hyacinth (jalkumbhi) covers ponds and lakes and chokes the plants and fish below.
• l.Digging sand, gravel and stones from rivers illegally and carelessly causes the banks to collapse, makes nearby farmland dry out, and destroys river life.

Conservation of biodiversity

Protecting plants and wild animals is the conservation of biodiversity. It keeps the natural environment in balance: when the numbers of plants and animals fall, the whole ecosystem suffers. Biodiversity must be conserved. There are two methods: in-situ and ex-situ conservation.

Table 4.3 Methods of conserving biodiversity

In-situ conservation (in the natural home)	Ex-situ conservation (outside the natural home)
national parks	botanical gardens
wildlife reserves	zoos
hunting reserves	nurseries
conservation areas	safari parks
protected natural sites and landscapes	aquariums
	seed banks, gene banks, embryo banks and sperm banks

In-situ conservation

Conserving wild plants and animals in their own natural habitat is called in-situ conservation (in situ is Latin for “in its place”). It is the easiest and best method, because the animals and plants live naturally, interacting freely with the soil, water, climate and other living things around them, and all species of the area are protected together, whether endangered or not.

Its challenges are forest fires, diseases and, above all, poaching for profit. Because the protected areas are large, these are hard to control.

Nepal has protected about a quarter of its land in this way. As of 2026, it has 13 national parks, 1 wildlife reserve, 1 hunting reserve and 6 conservation areas, plus buffer zones around the parks where local people live and share in the parks’ income.

Table 4.4 Nepal’s protected areas (in-situ conservation), as of 2026

National parks	Wildlife reserve	Hunting reserve	Conservation areas
1.Chitwan	1.Koshi Tappu	1.Dhorpatan	1.Annapurna
2.Sagarmatha			2.Kanchenjunga
3.Bardiya			3.Manaslu
4.Rara			4.Krishnasar
5.Khaptad			5.Gaurishankar
6.Langtang			6.Api Nampa
7.Makalu Barun
8.Shey Phoksundo
9.Shivapuri Nagarjun
10.Parsa
11.Banke
12.Shuklaphanta
13.Chhayanath (Mugu, declared 2025)

Ex-situ conservation

Conserving plants and animals outside their natural habitat, in a small, protected space made as much like their natural home as possible, is called ex-situ conservation (“out of its place”). It works especially well for species that are endangered: in a small area it is easier to look after them, treat them when they are ill, breed them and study them. But it is laborious and costly: their food and surroundings must be managed every day, and wild animals dislike a prison-like life in a cage.

Examples in Nepal: the Central Zoo in Jawalakhel, the National Botanical Garden in Godawari, the gharial and vulture breeding centers at Kasara in Chitwan (whose young are released into the wild), and the national gene bank at Khumaltar, Lalitpur, which stores the seeds of thousands of varieties of Nepal’s crops.

Other measures to conserve plants and animals:

• a.control poaching and the illegal trade in wild animals, plants and their body parts;
• b.set up more protected areas;
• c.control overgrazing, forest fires, pollution, and unplanned growth of towns and industries;
• d.make strong laws against poaching and illegal trade in wildlife, and enforce them;
• e.educate people about why biodiversity matters to everyone, and about every citizen’s duty to protect it.

1. Choose the best answer

2. Differentiate between

3. Give reasons

4. Answer these questions

People get most of what they need from nature and its ecosystem services. To use them, we build infrastructure: roads, bridges, dams, canals, buildings. When we build, we must think about whether it will last, so that people benefit from it for a long time. For that, we must think about the economic, social, cultural and environmental sides of every project.

Taking care of the economic, social, cultural and environmental aspects while building and running any project for people is called sustainable development. The most famous definition comes from the report Our Common Future of the Brundtland Commission (1987):

Sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

Sustainable development keeps the future in view, and builds a base for lasting progress. For example, if a bridge is built at a place where landslides are likely, and good measures against landslides are taken while building it, the bridge will last, and many generations will use it. If they are not, it may be swept away in the first big monsoon.

Aspects of sustainable development

Sustainable development tries to solve many problems of human society together: poverty, the infrastructure of development projects, social inequality, climate change, pollution and imbalance in the environment, biodiversity, the management of forests, and peace and justice. These different sides are called the aspects of sustainable development. There are three main aspects, also called the three pillars of sustainable development. Without all three, development lasts only a short time, and may even destroy the chance of doing better later:

1. the economic aspect
2. the social aspect
3. the environmental aspect

(a) Economic aspect

The economic aspect is about steady, balanced economic growth for people and nations: a strong and growing economy, with resources shared and used sensibly, without discrimination. It aims to meet the present generation’s needs in producing, distributing and using goods and services, but without exploiting (overusing and exhausting) resources.

(b) Social aspect

People of different backgrounds, beliefs and status live in every society. Development is sustainable only if the whole community progresses fairly together. That needs ending poverty, fair access to resources for all, empowering women and marginalized groups, people’s participation, protecting cultural identity, and peace and social justice. This is the social aspect. A prosperous society must look after all of these.

(c) Environmental aspect

For a prosperous society, the environment around it must stay productive and reliable. The fertility of the land, water, air, minerals, climate, and the biodiversity of plants and animals must be conserved. Using natural resources properly while keeping the ecosystem in balance is the environmental aspect. People need a steady supply of ecosystem services, so development projects must not destroy natural resources: roads, bridges and dams must be built with care for the environment, river banks and construction sites must be protected from erosion and landslides, and the natural homes of plants and animals must not be destroyed.

Principles of sustainable development

The principles of sustainable development are the guidelines to follow in every kind of development work, so that it lasts:

(a) Principle of ecosystem and biodiversity conservation

Keeping in mind how much the Earth can bear (its carrying capacity), development projects must conserve natural resources, ecosystems and biodiversity. This is the principle of ecosystem and biodiversity conservation. It stresses conserving natural resources, using renewable energy (sun, water, wind) and searching for new alternatives, controlling pollution, and conserving biodiversity.

(b) Principle of population control and human resource management

People use and consume far more natural resources than any other living thing. To keep natural resources available and reach sustainable development through people’s knowledge and skills, the human population must be kept within limits. Keeping the population within limits, so that the use of natural resources stays sustainable, is the principle of population control and human resource management. It says that responsible people should keep their families small, and that everyone’s knowledge and skills should be developed through education, training and awareness programs, so that people become a resource rather than a burden.

(c) Principle of cultural conservation and public participation

One person alone can do little, but when the public takes part, great things can be done. People take part in development only when their traditions and culture are respected and the work brings them prosperity and happiness. Conserving cultural heritage and building a positive attitude towards sustainable development in the community is the principle of cultural conservation and public participation. It stresses social justice and peace. For example, if the villagers themselves build an irrigation canal, they all feel it is theirs, they look after it, and the canal lasts a long time. Nepal’s community forests and farmer-managed irrigation systems work this way.

Importance of sustainable development

Development that cares for every aspect of society and the environment is sustainable development. It conserves and uses natural resources sensibly, protects the homes of plants and animals, keeps social justice, conserves traditions and culture, and brings happiness and prosperity to society. So it matters greatly today:

• a.It keeps the environment in balance and controls pollution.
• b.It conserves natural resources and makes people aware of using them sensibly.
• c.Big infrastructure projects (megaprojects) are built to its standards, so they last.
• d.It gradually ends social inequality and brings social justice, peace and harmony among people.
• e.It gives every person in society a fair share of economic opportunity.

Sustainable Development Goals and Nepal’s efforts

In 2015, at the 70th General Assembly of the United Nations, all 193 member countries agreed on the Sustainable Development Goals (SDGs), a shared plan for the whole world for 2016 to 2030. There are 17 goals and 169 targets, and progress is measured with about 230 indicators. The goals cover the economic, social and environmental aspects of development, each with a deadline. Nepal has made its own roadmap for the SDGs, with some extra indicators suited to Nepal, carried out through its periodic plans and yearly budgets.

All the goals are linked, directly or indirectly, to a better environment, but Goal 15 (Life on land) is the one about the environment and biodiversity: using land ecosystems sustainably, restoring and conserving them, managing forests well, stopping land from turning into desert, and halting the loss of biodiversity. Other goals include ending hunger (food security), fair and good-quality education for all, lifelong learning, clean drinking water and sanitation, strong infrastructure, decent jobs, action on climate change (Goal 13), and conserving the seas and oceans (Goal 14).

For food security, the main task is to protect farmland and native crops. For safe drinking water, sources and watersheds must be found and protected, which also needs sustainable infrastructure.

Biodiversity is directly harmed by climate change. It changes the life cycles of sea creatures, and on land it brings more floods, landslides, forest fires, very heavy rain, droughts, uneven rainfall and land drying into desert, all of which upset the balance of nature and the homes of plants and animals.

The air and the oceans are shared by the whole world, so, as global climate models show, damage to the environment in one place affects the whole Earth. Controlling pollution, cutting carbon dioxide emissions, planning industries and cities well, and using natural resources fairly and sensibly can only be achieved with the full support of every country.

Nepal is working towards these goals: reducing poverty, adapting to climate change, conserving biodiversity, spending more on quality education, and developing communities. Nepal was due to graduate from the group of Least Developed Countries (LDCs) on 24 November 2026; in 2026 it asked the United Nations for three more years, to 2029, to prepare (as of October 2026, the UN General Assembly was still to decide). Some of its efforts towards the goals:

• a.Since 2009, a Climate Change Council has guided programs to conserve water resources, watersheds and biodiversity at the local level, to reduce and adapt to the effects of climate change. To draw the world’s attention to climate change, Nepal’s government held a cabinet meeting at Kala Patthar, near Everest Base Camp, at about 5,250 m, on 4 December 2009, just before the world climate talks in Copenhagen. In 2018, the cabinet of Karnali Province met on the shore of Rara, Nepal’s largest lake (2,990 m). At Tsho Rolpa, a glacial lake at 4,580 m in the Rolwaling valley of Dolakha, which grows as the glacier above it melts, a channel with gates was built, and in 2000 the lake was lowered by 3 m to reduce the danger of it bursting; Imja Tsho near Everest was lowered by 3.4 m in 2016, and more lakes are planned.
• b.To conserve forests, Nepal began community forestry in the late 1970s. Since the Forest Act of 1993 handed forests over to local user groups, more than 22,000 groups now manage about a third of Nepal’s forests, and both the area and the density of forests have increased: forest and shrubland covered about 40 % of Nepal in the mid-1990s and about 45 % by 2015.
• c.Under the Fourteenth Plan (2016/17–2018/19), Nepal ran programs to reduce poverty, with vocational and technical education, skills for earning income, job creation, biodiversity awareness, and campaigns for education, sanitation and health for all.
• d.With the idea of a “clean, green and healthy environment”, the Fifteenth Plan (2019/20–2023/24) promised people the right to live in a healthy environment, by controlling pollution, managing solid waste and keeping homes and workplaces green. (The Sixteenth Plan, 2024/25–2028/29, carries this on.)
• e.The National Environment Policy, 2076 BS (2019) aims to secure people’s right to a clean environment by managing household and industrial waste, keeping cities green, and providing drains and public toilets.
• f.The Environment Protection Act, 2076 BS (2019) protects people’s right to live in a clean environment: polluters must pay compensation for the damage they cause; it seeks a balance between environment and development, and to reduce the effects of climate change on nature, the environment and biodiversity, and to face the challenges of global warming.

1. Choose the best answer

2. Differentiate between

3. Give reasons

4. Answer these questions