VIII Conservation of Plants And Animals

CBSE NCERT Conservation of Plants And Animals

What is biodiversity?

Biodiversity includes all organisms living in natural conditions. All kind of plants, animals and other organisms inhabiting a region make up its biodiversity. 

Biodiversity of the earth includes all organisms, bit and small – from an amoeba to a blue whale and from the algae to the mighty sequoia tree – that exist on our planet.

Flora and fauna

All the different kinds of plants on earth constitute its flora and all its different kinds of animals are collectively called its fauna.

Importance of biodiversity

Every component of biodiversity from microorganisms to the mighty Asiatic lion serves an important function in nature. The plants, animals and microorganisms together contributed in maintaining life on the earth.An ecosystem is made of all the plants, animals and microorganisms in an area along with non-living components such as climate, soil, river deltas, etc.

Environmental importance: 

Biodiversity maintains the environment around us. Plants and animals together maintain several natural cycles such as the oxygen, nitrogen and carbon cycles. These gases in turn play a crucial role in maintaining life on earth.

Deforestation and Its Causes

Deforestation means clearing of forests and using that land for other purposes. Trees in the forest are cut for some of the purposes mentioned below:·         _ Procuring land for cultivation.
·         _ Building houses and factories.
·         _ Making furniture or using wood as fuel

Consequences of Deforestation

Deforestation increases the temperature and pollution level on the earth. It increases the level of carbon dioxide in the atmosphere. Ground water level also gets lowered. If cutting of trees continues, rainfall and the fertility of the soil will decrease.

The increase in temperature on the earth disturbs the water cycle and may reduce rainfall. This could cause droughts.

Deforestation is a major cause which leads to the change in soil properties. Physical properties of the soil get affected by plantation and vegetation. Trees prevent soil erosion. Fewer trees result in more soil erosion.

Removal of the top layer of the soil exposes the lower, hard and rocky layers. This soil has less humus and is less fertile. Gradually the fertile land gets converted into deserts. It is called desertification.

Deforestation also leads to a decrease in the water holding capacity of the soil. The movement of water from the soil surface into the ground (infiltration rate) is reduced. So, there are floods. The other properties of the soil like nutrient content, texture, etc., also change because of  eforestation

Extinction of plants and animals

When the last individual of a particular kind of organism is believed to have died, the organism is declared extinct. For example, the pink-headed duck and the cheetah have become extinct from our country. 

When a species no longer exists in its natural habitat and is known only to survive in captivity, it is said to be extinct in the wild.

When the size of the population of an organism has reduced drastically and the organism is known to exits only in a few locations, there is a possibility that it will become extinct. Such an organism is classified as threatened.

If proper timely measures are taken to conserve their habitat, the threatened plants and animals can be saved. A threatened organism is endangered if there is a possibility of it becoming extinct in the near future.

Endemic species are those species of plants and animals which are found exclusively in a particular area.
They are not naturally found anywhere else. A particular type of animal or plant may be endemic to a zone, a state or a country.

Red Data Book is the source book which keeps a record of all the endangered animals and plants.
Species is a group of populations which are capable -of interbreeding.

Migratory animals face extinction because many of the places they used to migrate to have been altered by human actions. As a result, these animals do not have anywhere to go when weather conditions become harsh or food in their habitat becomes scarce.

Endemic plants and animals are those which live or grow in just one geographical area, often in small numbers. Such plants and animals are at a greater risk of becoming extinct. They are very vulnerable to local habitat disturbance.

The World Conservation Union or International Union for the Conservation of Nature and Natural Resources (IUCN) is an international organization dedicated to natural resource conservation.IUCN was responsible for the idea of compiling lists of threatened plants and animals as a means of drawing attention to those faces with extinction. These lists became known as Red Data Books (RDBs), ‘red’ stands for ‘danger’.

Conservation of biodiversity

To prevent any further loss of biodiversity, the existing populations must be maintained. This is known as conservation.

There are two main ways to conserve biodiversity:a. It can be conserved outside their natural habitat.b.  It can be conserved in their natural habitat.

Conserving biodiversity in their natural habitat

Conservation of endangered organisms in their natural habitats enables them to adapt continually to changing environmental conditions such as changes in climate.

Conservation measures in nature involves designating specific areas as protected sites. Protected sites are natural areas that are set aside to maintain biodiversity by allowing native organisms to flourish.

Protected sites or reserves

National Park : Areas reserved for wild life where they can freely use the habitats and natural resources.

Biosphere Reserve : Large areas of protected land for conservation of wild life, plant and animal resources and traditional life of the tribals living in the area.

Wildlife sanctuary: Areas where animals are protected from any disturbance to them and their habitat.

Reforestation

Reforestation is restocking of the destroyed forests by planting new trees. The planted trees should generally be of the same species which were found in that forest.

Answer these Questions

(a) Why should we conserve biodiversity?

Answer : We should conserve biodiversity, because biodiversity represent whole eco-system comprising land, water, air, fauna and flora. Each component of this biodiversity chain is inter dependent on each other for a sustainability.

(b) Protected forests are also not completely safe for wild animals. Why?

Answer : Even protected forests are not safe for wild animals because people living in the neighbourhood encroach upon them and destroy them.

(c) Some tribals depend on the jungle. How?

Answer : Some tribals depend on the jungle as they live in the deep forest like primitive people had lived in anciant time.They are still away from the basic amenities of modern life Forest provide them food items like seed grains, fruit, raw vegetables and other products like honey, meat of hunted wild animals for themselves, fodder for theirs animals, wood fuel for heating and cooking even clothing using natural fibres, leaves and animal skins.

(d) What are the causes and consequences of deforestation?

Answer : The main causes of deforestation are exploitation of forest resources by the human being to meet the ever growing requirements of an increasing population, rapid urbanization, industrialization. The consequences of deforestation will result in putting in danger, the whole existence of human being along with biodiversity on the planet earth.

(e) What is Red Data Book?

Answer : Red Data Book is the source book which keeps a record of all the endangered animals and plants

(f) What do you understand by the term migration?

Answer : Migration is the phenomenon of movement of a species from its own habitat to some other habitat for a particular time period every year for a specific purpose like breeding.

8th Conservation of Plants and Animals[Questions with Solution]

8th Conservation of Plants and animals : Science power Book for class 8th

8th Conservation of Plants and animals -Formative Assessment- Oral Questions - Fill in the blanks - Match the Columns - Think Zone – Puzzle /Quiz –and many more      Download/Read

                                                                                                                                       

8th Science Power  Solution - Conservation of Plants and animals       Download/Read