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iv. BiosphErE
It means the living world. It contains all forms of life such as plants, animals, human
beings, etc. Biosphere is a narrow zone of the earth where land, water and air interact
with each other to support life.
• It is a very significant part of the earth.

• It extends from less than 11 km below sea level to the troposphere.
• It is the part of the earth that is occupied by living organisms.
• It provides us favourable conditions for life.
• Both the biotic and abiotic environment are interdependent and provide a variety of
food and raw materials. All the plants, animals and human beings depend on their
surroundings. This inter relation between human beings and their surroundings form
as ecosystem.

ECosystEm

An ecosystem is a living community of plants and animals sharing an environment with non-
living elements such as climate and soil.
Ecosystems exist on a variety of scales. An example of a small scale ecosystem is a pond. A
medium scale ecosystem could be a forest. The tropical rain forest is an example of a very

large ecosystem (biome).
Sunlight is the main source of energy. This allows plants to convert energy by photosynthesis.
This provides food for some animals, birds and fish. These are called Herbivores. The other
animals eat the animals that have eaten the plants. These are Carnivores. This process
is called the food chain. The world has many different ecosystems. Each one has its own
climate, soil, plants and animals, very few ecosystems are natural today because of human

activities. More ecosystems are under threat than over
before and need protection.

In 1973, the villagers in the Alaknanda river valley of
Uttarakhand Protested against the indiscriminate cutting
down of trees. They did so by hugging the trees in order to
save them from being cut down. This movement became
famous as the Chipko Movement.

Ecosystem of a Pond human EnvironmEnt

Human beings are a part of the environment in which they live. They are to an extent
influenced by the atmosphere. They are also able to adapt and modify the environment
according to their needs.

With scientific and technological advancement, they have succeeded in controlling and
dominating nature. The interaction of human beings with environment is complex in nature.
It varies from place to place and time to time.

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