Natural Vegetation and Wildlife Chapter Notes | Footprints Class 7: Book Solutions, Notes & Worksheets PDF Download

Natural vegetation refers to the original and large-scale plant cover that grows naturally with little or no human interference. Also referred to as virgin vegetation, it includes every type of grass, herb, shrub or tree that grows under natural conditions in any region.

The type of natural vegetation found in an area depends on:

• the availability of sunlight
• temperature
• rainfall
• soil conditions

Natural vegetation of an area provides food and shelter for wildlife and so affects the type of wildlife found in an area. In this chapter, we shall learn about the different types of natural vegetation and wildlife associated with three natural terrestrial ecosystems, which are:

• deserts/shrub
• grasslands
• forests

Forest Ecosystem

A forest is an extensive, continuous area of land dominated by trees. Forests today occupy one-third of the land area of the Earth.

Tropical Evergreen Forests

• Location:
  • Found in hot and wet equatorial regions with heavy rainfall.
  • Also known as tropical rainforests or selvas.
  • Mainly found in southeast Asia, Africa along the Congo river basin, Papua New Guinea, other Pacific islands, and in South America along the Amazon and Orinoco river basins.
• Climate:
  • Hot and humid climate with heavy rainfall throughout the year.
• Vegetation:
  • The vegetation is dense and has a layered structure with various plant types.
  • Thick canopy prevents sunlight penetration, keeping forests evergreen even in the dry season.
  • Common trees: mahogany, ebony, rosewood, rubber.
• Wildlife:
  • Rich variety of wildlife including monkeys, apes, gorillas, leopards, elephants, pumas, jaguars, snakes like anaconda and python.
  • Colorful birds like parrots, pigeons, toucans, hornbills, hummingbirds, and jacamars.
  • Diverse insects and other creatures like millipedes, leeches, beetles, spiders, butterflies, moths, bats, lizards, frogs, turtles, crocodiles, and alligators in swamp areas.

Tropical Deciduous Forests

• Location: These forests are found in parts of the Indian subcontinent, Myanmar, Vietnam, Thailand, Central America, Brazil, and Northern Australia.
• Climate: Characterized by high temperatures, seasonal rainfall, and a distinct dry season.
• Vegetation:
  • The deciduous nature of vegetation is due to the seasonal rainfall, with trees shedding their leaves in the dry season to conserve moisture.
  • Trees are medium in height, widely spaced, and less dense, allowing sunlight penetration. Thick undergrowth of bushes and shrubs is present.
  • Various trees like teak, sal, deodar, sandalwood, bamboo, and ferns thrive in dense jungles with heavy rainfall.
  • Acacia, eucalyptus, and thorny shrubs appear in areas with lower rainfall.
  • Lumbering is common due to forest accessibility and commercial viability of trees.
  • Mangrove forests, such as sundari trees in the Ganga-Brahmaputra Delta, grow in swampy and deltaic tracts.
• Wildlife:
  • Various animals like tigers, elephants, bears, deer, monkeys, rhinoceros, hippos, buffaloes, nilgais, and pandas inhabit these forests.
  • Birds ranging from parrots, pigeons, sparrows to water birds like ducks, cranes, storks, and herons are abundant.

Temperate Evergreen Coniferous Forests (Taiga)

• Location: Found between 50°N and 70°N latitudes in southern Canada, Norway, Sweden, Poland, Finland, and northern Russia.
• Climate: Bitterly cold winters, short warm summers, and mostly snow precipitation.
• Vegetation:
  • Evergreen trees like spruce, hemlock, fir, pine, and cedar grow tall and straight, adapted to survive the harsh climate.
  • Roots spread horizontally to cope with frozen subsoil in winter, with branches shedding snow and ice without breakage.
  • No undergrowth is present.
  • Lumbering is a significant occupation, with products like paper, matchsticks, newsprint, sports goods, and furniture manufactured.
• Wildlife:
  • Small animals such as opossums, raccoons, beavers, muskrat, musk ox, lynx, silver fox, sable, and antelope are common due to cold winters.
  • Birds like crossbills, whooping cranes, spruce grouse, black grouse, and capercaillies feed on conifer shoots and cones.

Temperate Deciduous and Cool & Temperate Mixed Forests

• Location: The warm temperate deciduous forests are found between latitudes 30°N to 40°N on the eastern sides of most continents. They are located in Japan, Eastern Russia, Korea, North China, Eastern Canada, and Northeast USA. Beyond 40°N and 50°N and 40°S to 50°S are the cool temperate forests that have both deciduous and coniferous trees and hence are known as mixed forests. They are found in Western and Central Europe, Western Canada, Northwest USA, South Chile, Tasmania, and South New Zealand.
• Climate: The region is characterized by warm summers with cool winters and moderate rainfall received throughout the year.
• Vegetation:
  • With broad leaves, thick trunks, and dense foliage, deciduous trees such as oak, ash, and elm that shed their leaves in autumn and have a rest period during the cool winters cover most of both regions.
  • At higher latitudes where the climate gets cooler, the deciduous trees are mixed with coniferous trees like fir, spruce, larch, beech, birch, hemlock, and juniper.
• Wildlife:
  • Wolf, puma, brown bear, fox, lynx, deer, vole, and wild horse are the main wildlife.
  • Rabbit, shrew, stoat, squirrels, woodchuck, chipmunks, and weasels are also seen.
  • The forests have a rich birdlife of robins, hawks, eagles, falcons, swallows, and owls.

Mediterranean Forests

• Location: This type of vegetation is found around the Mediterranean Sea in southern Europe, northern Africa, and western Asia, California, South-west Africa, South-west Australia, and Central Chile.
• Climate: Summers are hot and dry while winters are cool and wet in this region.
• Vegetation:
  • To adapt to the summer drought, drought-resistant and widely-spaced vegetation with short trees, small waxy leaves, and thick barks is found.
  • The vegetation has long roots which go deep under the soil in search of moisture.
  • The trees found in this region are oak, fig, pine, olive, laurel, cypress, myrtle, etc.
• Wildlife: The main forms of wildlife found here are wild goats, rabbits, wolves, wild boars, reptiles, eagles, vultures, and insects.

Grasslands Ecosystem

Tropical Grasslands

• Location: These grasslands are located on either side of the tropical rainforests and include a large part of Africa (known as savanna); parts of South America (known as campos and llanos); parts of the Deccan Plateau and northern Australia.
• Climate: Summers are hot and wet, winters are dry and warm, and rainfall occurs only for 6 to 8 months in a year, which is inadequate for the growth of a forest.
• Vegetation:
  • Tall coarse grass is the main type of vegetation which may grow more than 2 m in height during the summer. Referred to as elephant grass, it dries up and turns brown in winter, giving a very parched appearance. Long roots ensure that the grass survives till the next rainy season.
  • There are a few scattered trees in the savanna, especially where the rainfall is higher, such as baobab and acacia. Some trees, like the bottle tree or baobab, store water inside the trunk, while others like the acacia have small leaves to reduce water loss.
  • The vegetation here adapts itself to the climate and is able to withstand the winter drought.
• Wildlife: These grasslands, especially in Africa, are home to a rich variety of wildlife including carnivores, omnivores, herbivores, and flightless birds. Animals adapt to survive the dry season by migrating to forest margins or congregating near waterholes.

Temperate Grasslands

• Location: These grasslands lie in the temperate zone between 25° and 55° latitudes in both hemispheres in the interiors of continents. Examples include the prairies of North America, the steppes of Eurasia, the downs of Australia, the pampas of South America, and the high veld of South Africa.
• Climate: The region experiences extremes of temperature with warm summers and cold winters. Rainfall is inadequate for the growth of trees and usually occurs in the summer.
• Vegetation:
  • Short, soft grasses grow in temperate grasslands, which are practically treeless except for a few scattered trees like willow, alder, and poplar.
• Wildlife: Temperate grasslands are home to a variety of animals such as bison, pronghorn, wild horses, coyotes, rabbits, wolves, and wild asses. In Australia, marsupials like the kangaroo and flightless birds like emus are found. Flocks of birds like budgerigars and sparrows are attracted by grass seeds.

Desert Ecosystem

Deserts occur in areas of scanty rainfall and are characterized by aridity. According to the temperature conditions, deserts are classified into three types—tropical deserts, temperate deserts, and polar deserts.

Tropical Deserts

• Location:
  • The tropical deserts are located between the two tropics along the western margin of continents.
  • The main deserts are the Sahara, Namib, and the Kalahari in Africa; the Atacama in South America; the Arabian and Thar in Asia; and the Great Australian Desert.

Climate: Extremes of temperature and lack of rainfall characterize the climate of the hot deserts.

• Vegetation:
  • Deserts have very little or no vegetation due to the lack of rainfall.
  • The vegetation is xerophytic or drought-resistant and can adapt to the hot, dry climate.
  • The plants have long tap roots to reach underground water, fleshy stems that hold water, no leaves and spines (modified leaves), and waxy surfaces to check evaporation.
  • Cactus, acacia, thorny bushes, and date palm are common.
• Wildlife:
  • Wildlife in the deserts shows excellent adaptation to the region.
  • The camel, also known as the 'ship of the desert,' is the most important animal here.
  • Antelopes, gazelles, wild asses, hare, rodents, desert foxes, lizards, snakes, and hyenas are also found here.
• Temperate Deserts
  • Location: Found in the interior regions of continents like the Gobi Desert, Tibetan Plateau in Asia, and the Patagonian Desert in South America.
  • Climate: Harsh conditions with extremely high temperatures in summer (e.g., 50°C in the Gobi Desert) and freezing temperatures in the Patagonian Desert. Most precipitation falls during summer, often as snow.
  • Vegetation: Mostly barren with limited vegetation such as thorny bushes, shrubs, coarse grass, and saltwort.
  • Wildlife: Home to animals like wolves, Bactrian camels, mountain goats, iguanas, black-tailed gazelles, gerbils, voles, and jerboas. Some animals live in underground burrows to escape extreme temperatures.
• Tundra/Polar Deserts
  • Location: Located in Northern Canada, Alaska, southern Greenland, and Northern Eurasia bordering the Arctic Ocean.
  • Climate: Annual precipitation less than 2.5 cm, mean temperature during warmest months less than 10°C, ground frozen to depths of hundreds of meters (permafrost), snow dunes common where precipitation is higher. Sun remains low in the sky or below the horizon during winters.
  • Vegetation: Severe conditions prevent tree growth; only a few bushes and dwarf willows survive in sheltered areas. Berries like cranberry, Arctic flowering plants, and hardy plants like moss and lichen appear in summer.
  • Wildlife:
    • Animals have fur and thick fat layers to survive the cold climate. Land animals include reindeer or caribou, musk ox, polar bears, foxes, dogs, and wolves.
    • Coasts are inhabited by whales, seals, walruses, and various fish. Birds migrate to warmer regions during the cold season.