Grade 4 · Unit 2: Living things and environments

How we affect the environment

People can harm habitats – and protect them.

Forests are cut down for wood and to make space for farms and towns.

Losing habitats

People need space for homes, farms, roads and factories. Cutting down large areas of forest is called deforestation. When a habitat is destroyed, the animals and plants that lived there lose their home.

Bangladesh loses some of its hill forests to farming and building. When forests are cleared on slopes, heavy rain can wash the soil away and cause landslides.

Pollution

Pollution from factories, cars and rubbish harms living things. Dirty water kills fish and makes people ill. Plastic litter can trap or choke animals.

Dyes and chemicals from some factories have polluted rivers near Dhaka. New water-treatment plants clean the waste water before it reaches the river.

Animals in danger

When habitats shrink, some animals become endangered. Bengal tigers in the Sundarbans and Asian elephants in the hills are at risk. If the last ones die, they are gone for ever.

Asian elephants, Ganges river dolphins and hilsa fish are also at risk. Protecting their habitats protects many other living things too.

Caring for nature

Conservation means protecting nature. Bangladesh protects places like the Sundarbans and Lawachara National Park. We can all help by planting trees, saving water and putting litter in bins.

In Bangladesh, coastal villages plant mangrove trees along the shore. The trees protect homes from storm waves and become new homes for wildlife.

What I learnt