NCERT Explained: Class VII Geography, Chapter 6 - Natural Vegetation and Wildlife: Exploring Earth's Green Blankets

Introduction to the Topic

Have you ever noticed how the trees and plants around you change when you travel from a hot, humid coastal area to a cool, breezy hill station? This is not a coincidence! The growth of vegetation depends primarily on two major factors: temperature and moisture. Additionally, factors like the slope of the land and the thickness of the soil play a crucial role in determining what kind of plants grow in a specific region. In this chapter of NCERT Class VII Geography, we embark on a journey to understand the diverse 'green blankets' of our Earth, known as natural vegetation, and the fascinating wildlife that calls these places home.

Natural vegetation refers to the plant community that has grown naturally without human aid and has been left undisturbed by humans for a long time. Based on the variations in temperature and rainfall, natural vegetation is generally classified into three broad categories: Forests, Grasslands, and Shrubs. Understanding these categories helps us appreciate how life adapts to different climatic conditions across the globe.

Key Concepts Explained

1. Forests: The Majestic Canopies

Forests grow where temperature and rainfall are plentiful to support a thick tree cover. Depending on these factors, forests are further divided into several types:

Tropical Evergreen Forests

Also known as tropical rainforests, these forests occur in the regions near the equator and close to the tropics. These regions are hot and receive heavy rainfall throughout the year. Because there is no particular dry season, the trees do not shed their leaves altogether. This is why they are called evergreen. The thick canopies of the closely spaced trees do not allow sunlight to penetrate inside the forest even in the daytime. Hardwood trees like rosewood, ebony, and mahogany are common here. In the Amazon basin of South America, these forests are so vast they are called the 'lungs of the world.' The wildlife is equally spectacular, featuring the Anaconda, one of the world's largest snakes, which lives in these tropical waters.

Tropical Deciduous Forests

These are the monsoon forests found in large parts of India, Northern Australia, and Central America. These regions experience seasonal changes. Trees shed their leaves in the dry season to conserve water. The hardwood trees found in these forests, such as sal, teak, neem, and shisham, are \textremely useful for making furniture, transport, and construction materials. Common animals include tigers, lions, elephants, langurs, and monkeys.

Temperate Evergreen Forests

Located in the mid-latitudinal coastal regions, these forests are commonly found along the eastern margins of continents, such as South East USA, South China, and South East Brazil. They comprise both hard and soft wood trees like oak, pine, and eucalyptus.

Temperate Deciduous Forests

As we go towards higher latitudes, we find these forests in places like the North Eastern part of USA, China, New Zealand, Chile, and coastal regions of Western Europe. They shed their leaves in the dry season. Common trees include oak, ash, and beech. Deer, foxes, and wolves are the animals commonly found here, along with birds like pheasants and monals.

Mediterranean Vegetation

The west and south-west margins of the continents are different. They have Mediterranean vegetation, mostly found in the areas around the Mediterranean Sea in Europe, Africa, and Asia. This vegetation is also found outside the actual Mediterranean region in California (USA), South West Africa, and South West Australia. These regions are marked by hot dry summers and mild rainy winters. Citrus fruits such as oranges, figs, olives, and grapes are commonly cultivated here because people have removed the natural vegetation to grow what they want. There isn't much wildlife here compared to other forests.

Coniferous Forests

In the higher latitudes (50°–70°) of the Northern Hemisphere, the spectacular Coniferous forests are found. These are also called Taiga. These forests are also seen in higher altitudes. They are tall, softwood evergreen trees. The woods of these trees are very useful for making pulp, which is used for manufacturing paper and newsprint. Matchboxes and packing boxes are also made from softwood. Chir, pine, and cedar are important varieties of trees. Silver fox, mink, and polar bear are the common animals found here.

2. Grasslands: The Open Vistas

Grasslands occur in regions of moderate to low rainfall. They are divided into two categories:

Tropical Grasslands

These occur on either side of the equator and \textend to the tropics. This vegetation grows in areas of moderate to low amounts of rainfall. The grass can grow very tall, about 3 to 4 metres in height. The Savannah grasslands of Africa are of this type. Common animals include elephants, zebras, giraffes, deer, and leopards.

Temperate Grasslands

These are found in the mid-latitudinal zones and in the interior part of the continents. Usually, the grass here is short and nutritious. Wild buffaloes, bisons, and antelopes are common in the temperate region.

3. Thorny Bushes and Tundra: Life in Extremes

In regions where conditions are too harsh (too dry or too cold), specialized vegetation survives.

Thorny Bushes

These are found in the dry deserts. Tropical deserts are located on the western margins of the continents. The vegetation cover is scarce here because of scanty rain and scorching heat. Plants here often have thick stems and waxy leaves or thorns to prevent water loss.

Tundra Vegetation

If you reach the polar regions, you will find the place \textremely cold. The growth of natural vegetation is very limited here. Only mosses, lichens, and very small shrubs are found. It grows during the very short summer. This is called Tundra type of vegetation. This vegetation is found in the polar areas of Europe, Asia, and North America. The animals have thick fur and thick skin to protect themselves from the cold climatic conditions. Seal, walruses, musk-oxen, Arctic owl, polar bear, and snow foxes are some of the animals found here.

Summary & Key Takeaways

• Climatic Dependency: Natural vegetation is directly linked to climatic conditions like temperature and moisture.
• Forests: Range from Tropical Evergreen (high rain) to Coniferous (high altitude/latitude).
• Mediterranean Regions: Known as the 'Orchards of the World' for their fruit cultivation.
• Grasslands: Savannas represent tropical grasslands, while nutritious short-grass plains represent temperate ones.
• Extreme Adaptations: Desert plants use thorns to save water, while Tundra plants grow only during short summers.
• Human Impact: Much of the natural vegetation is being cleared for agriculture and habitation, which impacts wildlife habitats.