Chapter 5 Natural Vegetation And Wildlife

Overview

India is a mega-biodiverse country, ranking high globally in plant and animal diversity. This chapter explores India's natural vegetation and wildlife, explaining how factors like relief, soil, and climate (temperature, photoperiod, precipitation) influence the types of vegetation found. It details the major types of vegetation in India, from tropical evergreen to alpine, and discusses the rich diversity of fauna. The chapter also highlights the importance of conservation, the threats to biodiversity, and the measures taken by the government to protect flora and fauna, including wildlife protection acts and the establishment of bio-reserves.

Relief

The physical features of the land significantly impact vegetation:

• Land: Different terrains like plains, plateaus, and mountains support varied vegetation. Fertile plains are ideal for agriculture, while rough terrains host grasslands and woodlands, providing habitats for wildlife.
• Soil: Soil type dictates vegetation; sandy desert soils support cacti and thorny bushes, marshy soils support mangroves, and hilly slopes with adequate soil depth host conical trees.

Climate

Climate is a primary determinant of vegetation:

• Temperature: Changes in temperature with altitude lead to distinct vegetation zones. Tropical zones (above 24°C mean annual temp.) transition to subtropical (17-24°C), temperate (7-17°C), and alpine (below 7°C) vegetation at higher altitudes, with frost and snow becoming more prevalent.
• Photoperiod (Sunlight): Variations in day length influence plant growth, with longer sunlight duration promoting faster growth, especially in summer.
• Precipitation: Areas with heavy rainfall support dense vegetation, while regions with less rainfall have sparse vegetation. For example, the Western Ghats receive more rain on their windward slopes, leading to denser forests compared to the leeward eastern slopes.

Forests are vital for the environment, moderating climate, preventing soil erosion, regulating water flow, supporting industries, providing livelihoods, and enhancing recreation. However, human activities like agriculture, industrialization, urbanization, and over-grazing have significantly altered natural vegetation.

Types Of Vegetation

India's diverse climate supports various vegetation types:

• Tropical Evergreen Forests: Found in areas with over 200 cm rainfall and short dry seasons (e.g., Western Ghats, Andaman & Nicobar, Assam). These forests have multilayered vegetation reaching up to 60m and remain green year-round.
• Tropical Deciduous Forests: The most widespread, found in regions with 70-200 cm rainfall. Trees shed leaves during the dry summer. They are divided into:
  • Moist Deciduous: (100-200 cm rainfall) Found in the eastern parts of India, foothills of Himalayas, Jharkhand, Odisha, Chhattisgarh. Dominated by teak.
  • Dry Deciduous: (70-100 cm rainfall) Found in drier parts of the Peninsula and plains of UP/Bihar. Features open stretches with teak, sal, peepal, and neem.
• Tropical Thorn Forests and Scrubs: Occur in regions with less than 70 cm rainfall (e.g., northwestern India, semi-arid areas). Characterized by thorny trees (Acacia, euphorbia, cactus) with deep roots and succulent stems to conserve water.
• Montane Forests: Found in mountainous areas, changing with altitude.
  • Wet Temperate: (1000-2000m) Broad-leaf evergreen trees like oak and chestnut.
  • Temperate: (1500-3000m) Coniferous trees like pine, deodar, fir, spruce, and cedar.
  • Alpine Vegetation: (Above 3,600m) Stunted trees, shrubs, mosses, and lichens; used for grazing by nomadic tribes.
• Mangrove Forests: Found in coastal areas influenced by tides, with dense mangroves and specialized root systems. Deltas of major rivers like Ganga, Mahanadi, Krishna, Godavari, and Kaveri are covered by these forests. The Sundarbans are famous for Sundari trees and the Royal Bengal Tiger.

Medicinal Plants

India has a rich tradition of using medicinal plants, with many species described in Ayurveda. Commonly used plants include Sarpagandha (for blood pressure), Jamun (for digestion and diabetes control), Arjun (for earache and blood pressure), Babool (for eye sores and as a tonic), Neem (antibacterial), Tulsi (for coughs/colds), and Kachnar (for asthma/ulcers).

Wildlife

India boasts approximately 90,000 animal species, including diverse birds, fish, amphibians, reptiles, and mammals. Majestic elephants are found in hot, wet forests, while one-horned rhinos inhabit Assam and West Bengal. Arid regions are home to wild asses and camels. Other animals include bison, nilgai, deer, and various monkeys. India is unique for having both tigers (found in Madhya Pradesh, Sundarbans, Himalayas) and lions (Gir Forest, Gujarat). Himalayan wildlife includes yak, Tibetan antelope, snow leopards, and red pandas. Rivers and coastal areas host turtles, crocodiles, and gharials. Birdlife is abundant, with peacocks, parakeets, and cranes being common.

Migratory Birds

Several Indian wetlands attract migratory birds during winter, such as the Siberian Crane in the Rann of Kachchh, where flamingos also congregate.

Conservation Efforts

Recognizing the threats to biodiversity from habitat destruction and over-exploitation, the Indian government has implemented conservation measures:

• Wildlife Protection Act, 1972: Enacted to protect flora and fauna.
• Bio-reserves: 18 bio-reserves established, with ten included in the world network (e.g., Sundarbans, Nanda Devi, Nilgiri).
• Financial and Technical Assistance: Provided to botanical gardens since 1992.
• Projects: Initiatives like Project Tiger, Project Rhino, and Project Great Indian Bustard protect specific species.
• Protected Areas: 103 National Parks, 535 Wildlife Sanctuaries, and Zoological Gardens are established for conservation.

Conservation is essential as every species plays a role in the ecosystem. Indiscriminate destruction of the natural environment must cease for human survival.

Exercise

The exercises in this chapter cover the diversity of India's natural vegetation and wildlife. They include identifying vegetation types (rubber, cinchona), locations of bio-reserves, and classifying forest types. Students are asked to explain the factors influencing vegetation distribution, define bio-reserves, name animals found in different vegetation zones, and differentiate between forest types. Questions also address the reasons for endangered species and the richness of India's flora and fauna heritage. Map skills involve locating areas of different forest types and national parks. Project activities encourage students to identify medicinal plants, explore forest-based occupations, write about wildlife importance, and engage in tree planting.