This chapter focuses on climate change, endangered plants and animals, biodiversity, conservation measures, and medicinal plants in Nepal. It explains causes, effects, and solutions for environmental problems, and highlights the importance of protecting biodiversity and using medicinal plants sustainably.
1. Climate Change
Definition
Climate change is the long-term change in average weather patterns (temperature, rainfall, wind, etc.) of a place or the Earth as a whole.
Causes of Climate Change
A. Natural Causes
- Volcanic eruptions (release ash and gases)
- Changes in solar radiation
- Changes in Earth’s orbit and tilt
- Reflection of sunlight by ice and clouds
B. Human (Man-made) Causes
- Burning of fossil fuels (coal, petrol, diesel)
- Industrialization
- Deforestation
- Vehicle emissions
- Use of chemical fertilizers and pesticides
- Urbanization
Effects of Climate Change
- Irregular rainfall, floods, droughts
- Melting of glaciers and rising sea level
- Loss of biodiversity and extinction of species
- Decrease in agricultural production
- Increase in diseases (skin diseases, respiratory problems, malnutrition)
- Change in seasonal cycle
Control / Preventive Measures
- Use renewable energy (solar, wind, hydro)
- Afforestation and reforestation
- Reduce pollution
- Use public transport
- Follow environmental laws
- Promote sustainable development
2. Biodiversity
Definition
Biodiversity is the variety of living organisms found in a particular area or on Earth, including plants, animals, and microorganisms.
Levels of Biodiversity
- Genetic Diversity
Variation of genes within the same species
Example: Different varieties of rice - Species Diversity
Variety of different species in an area
Example: Tiger, deer, birds in a forest - Ecosystem Diversity
Variety of ecosystems
Example: Forests, grasslands, wetlands, deserts
Importance of Biodiversity
- Maintains ecological balance
- Provides food, medicine, raw materials
- Helps in pollination and nutrient cycling
- Supports human survival
- Economic and cultural importance
3. Endangered Plants and Animals of Nepal
Definition
Endangered species are plants and animals whose population has decreased drastically and are at risk of extinction.
Causes of Endangerment
- Climate change
- Habitat destruction
- Illegal hunting and trade
- Pollution
- Forest fires
- Introduction of invasive species
Examples of Endangered Animals of Nepal
Mammals
- One-horned Rhinoceros
- Bengal Tiger
- Red Panda
- Snow Leopard
Birds
- Sarus Crane
- Great Hornbill
Reptiles
- Gharial
- Asiatic Rock Python
Conservation Measures
- Protect natural habitats
- Stop illegal hunting and wildlife trade
- Establish national parks and reserves
- Scientific research and monitoring
- Public awareness programs
4. Conservation of Biodiversity
A. In-situ Conservation
Conservation of plants and animals in their natural habitat.
Examples:
- National Parks
- Wildlife Reserves
- Conservation Areas
Examples in Nepal:
- Chitwan National Park
- Sagarmatha National Park
- Bardia National Park
B. Ex-situ Conservation
Conservation of plants and animals outside their natural habitat.
Examples:
- Zoo
- Botanical garden
- Seed bank
- Nursery
5. Medicinal Plants
Definition
Medicinal plants are plants that are used to prepare medicines to prevent or cure diseases.
Importance of Medicinal Plants
- Used in traditional and modern medicine
- Economically valuable
- Fewer side effects
- Cultural importance
- Source of income for local people
Common Medicinal Plants of Nepal
| Medicinal Plant | Scientific Name | Uses |
|---|---|---|
| Tulsi | Ocimum tenuiflorum | Cold, cough, improves immunity |
| Neem | Azadirachta indica | Skin diseases, blood purifier |
| Gurjo | Tinospora cordifolia | Immunity booster |
| Ghod Tapre | Centella asiatica | Memory improvement |
| Turmeric | Curcuma longa | Anti-inflammatory |
| Asuro | Adhatoda vasica | Respiratory problems |
| Bojo | Acorus calamus | Throat and digestion problems |
| Aloe Vera | Aloe barbadensis | Skin care, digestion |
| Yarsagumba | Cordyceps sinensis | Energy booster |
Conservation of Medicinal Plants
- Cultivation in nurseries
- Sustainable harvesting
- Protection of natural habitats
- Public awareness and education
- Government policies
6. Sustainable Use of Natural Resources
Definition
Sustainable use means using natural resources wisely without harming the environment so that future generations can also use them.
Examples
- Controlled harvesting of medicinal plants
- Use of renewable energy
- Forest conservation
- Wildlife protection