krit.club logo

Conservation of Biodiversity - Migration and Reforestation

Grade 8CBSE

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

•

Migration is the periodic, seasonal movement of animals or birds from their natural habitat to other places to escape harsh climatic conditions or for breeding purposes.

•

Birds that fly very long distances to reach another land are known as migratory birds. A famous example is the Siberian crane, which travels from Siberia to India (Bharatpur) during winters.

•

Reforestation is the restocking of destroyed forests by planting new trees. Ideally, the planted trees should be of the same species that were originally found in that forest.

•

Reforestation can happen naturally if the deforested area is left undisturbed; the vegetation re-establishes itself without human interference.

•

Plants consume CO2CO_2 for photosynthesis. A decrease in the number of trees leads to an increase in the concentration of CO2CO_2 in the atmosphere, leading to global warming: ↑CO2  ⟹  ↑Temperature\uparrow CO_2 \implies \uparrow \text{Temperature}.

•

The Forest (Conservation) Act in India aims at the preservation and conservation of natural forests while meeting the basic needs of the people living in or near the forests.

•

Paper conservation is linked to biodiversity; it takes approximately 1717 full-grown trees to make 11 tonne of paper. Recycling paper saves trees, energy, and water.

📐Formulae

6CO2+6H2O→Sunlight/ChlorophyllC6H12O6+6O26CO_2 + 6H_2O \xrightarrow{\text{Sunlight/Chlorophyll}} C_6H_{12}O_6 + 6O_2

Total Trees Saved=Recycled Paper (tonnes)×17\text{Total Trees Saved} = \text{Recycled Paper (tonnes)} \times 17

ΔBiodiversity∝Reforestation Rate−Deforestation Rate\Delta \text{Biodiversity} \propto \text{Reforestation Rate} - \text{Deforestation Rate}

💡Examples

Problem 1:

Explain why global warming occurs when forests are cleared, using scientific notation for the gases involved.

Solution:

Plants use CO2CO_2 for photosynthesis. When trees are cut, fewer trees are available to absorb CO2CO_2 from the atmosphere. This results in an increased amount of CO2CO_2. Since CO2CO_2 traps the heat rays reflected by the earth, the increase in its concentration leads to an increase in the earth's temperature, known as global warming.

Explanation:

The greenhouse effect is amplified by the excess CO2CO_2 which acts as a thermal blanket.

Problem 2:

If a school decides to recycle 55 tonnes of paper per year, how many full-grown trees are they effectively saving?

Solution:

5 tonnes×17 trees/tonne=85 trees5 \text{ tonnes} \times 17 \text{ trees/tonne} = 85 \text{ trees}

Explanation:

Since 11 tonne of paper requires 1717 trees, we multiply the total tonnage by the constant 1717 to find the number of trees preserved.

Problem 3:

What is the primary reason for the migration of the Siberian Crane to India?

Solution:

The Siberian Crane migrates to India because the winters in Siberia are extremely cold and inhospitable. The cranes travel to regions like Bharatpur in Rajasthan and Sultanpur in Haryana to find favorable temperatures and food during the winter months.

Explanation:

Migration is a survival strategy to escape environmental extremes and ensure successful breeding.