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Short Notes: Forests - Our Lifeline

FOREST

Short Notes: Forests - Our Lifeline

An area with high density of trees is called a forest. A forest is a system which is composed of plants, animals and microorganisms. 

Forest as Habitat: 

Forest is the habitat for a variety of living beings. Many plants, animals and microbes live in the forest. 

A typical tree forest is composed of two distinct layers, viz. overstory ( or canopy) and understory. A tree can be divided into two parts: trunk and branches. The branches of a tree make its crown. 
Crowns of several trees; in the forest; make the canopy. In dense forests, the canopy looks like the roof of the forest. There are many animals and creatures which live only on the canopy, e.g. monkeys. 

Crowns of trees come in various shapes. Some common examples are shown in the given figure.

Fig: Types of treesFig: Types of trees 

The lower layer of the forest is called understory. It is composed of herbs and shrubs. The understory is a different world in itself. The understory may not get proper sunlight in dense forests. 

There are many animals and creatures which live only in the understory of a forest. 

MULTIPLE CHOICE QUESTION

Try yourself: What are the two distinct layers in a typical tree forest?

A

Canopy and roots

B

Trunk and branches.

C

Overstory and understory.

D

Canopy and trunk.

Review Questions 

Ques 1 - What is forest? 

Answer:An area with dense cover of trees is called forest. 

Ques 2 - What is overstory in a forest? 

Answer:The upper leafy portion of a forest is called overstory. 

Important Forest Produce: Many important forest produce are useful for us. Some examples are given below:
Short Notes: Forests - Our Lifeline

  • Firewood and dry leaves are used as kitchen fuel in villages which are close to a forest.

  • Timber is an important raw material; for construction activities and for making furniture and artifacts.

  • Wood pulp is used in manufacturing paper.

  • Honey, kendu leaves, catechu, lac, raisin, etc. are important forest produce.

  • Many medicinal plants and herbs are found in forests. 

Forest as a System: 

Every part of the forest contributes in making a self-sustaining system. The green plants prepare food through photosynthesis. The herbivores directly take food from the green plants. The carnivores take food from the herbivores. This makes a food chain, which can be shown by following example: 

Grass → Deer → Lion 

When an animal or a plant dies, its dead remains rot in due course of time and turn into soil-like thing. The process is called decomposition and microorganisms carry out this process. Decomposition is the process by which all the raw materials are returned to the nature. The soil-like thing made after decomposition is called humus. It makes the soil highly fertile. The topsoil of forest is fertile because of presence of humus. 

Role of Forest in Preserving the Environment: Forest plays an important role in preserving the environment. Green plants take solar energy and convert it into chemical energy while making food. Thus, solar energy is transferred to other living beings through the green plants. Green plants utilize carbon dioxide during photosynthesis and release oxygen. That is how the green plants maintain the balance of carbon dioxide and oxygen in the environment. 

Role of Forest in Water Cycle:The roots of the trees make the soil porous. Rainwater seeps through these pores and recharge groundwater. Forests prevent wastage of rainwater in the form of runoff. Forests also prevent flash floods by slowing down the movement of water. 

Role of Forest in Soil Conservation:The roots of the trees hold the topsoil in place. This prevents soil erosion by wind or by running water. 

MULTIPLE CHOICE QUESTION
Try yourself: What is the role of forests in preserving the environment?
A

Forests help in preserving the environment by releasing carbon dioxide during photosynthesis.

B

Forests maintain the balance of carbon dioxide and oxygen in the environment.

C

Forests prevent soil erosion by wind or running water.

D

Forests recharge groundwater by allowing rainwater to seep through the soil.


Deforestation and its Effect: Large scale cutting of trees to clear land for human use is called deforestation. Due to growing human population, vast tracts of forest have been removed. This has created many problems. Some of them are given below: 
  • Reduced forest cover has led to soil erosion and loss of soil fertility at many places.
  • Reduced forest cover has disturbed the natural process of recharging of groundwater. This has resulted in shortage of drinking water at many places.
  • Reduced forest cover means there is loss of habitat for many animals. Existence of most of the animals is in danger because of this.
  • Reduced forest cover means there is higher percentage of carbon dioxide in the atmosphere. This is leading to global warming. The average temperature of the earth is on the rise.

Review Questions: 

Ques 1 - What do you understand by deforestation? 

Answer:Large scale cutting of trees to clear land for human use is called deforestation. 

Ques 2 - What is humus? 

Answer:The part of the topsoil which is composed of decomposed remains of plants and animals is called humus.

The document Short Notes: Forests - Our Lifeline is a part of the Class 7 Course Science Class 7 (Old NCERT).
All you need of Class 7 at this link: Class 7

FAQs on Short Notes: Forests - Our Lifeline

1. Why are forests considered important for our survival?
Ans. Forests are vital for our survival as they produce oxygen, absorb carbon dioxide, and act as a habitat for numerous species. They also provide resources like timber, fuel, and medicinal plants, which are essential for human life.
2. How do forests help in maintaining the ecosystem?
Ans. Forests play a crucial role in maintaining the ecosystem by supporting biodiversity, regulating the water cycle, preventing soil erosion, and contributing to climate regulation. They provide a balanced environment for various plants and animals to thrive.
3. What are the main threats to forests today?
Ans. The main threats to forests today include deforestation due to agriculture, urbanization, and logging, as well as climate change, forest fires, and pollution. These factors lead to habitat loss and diminished biodiversity.
4. How can we protect forests for future generations?
Ans. We can protect forests by promoting sustainable practices like afforestation, conservation efforts, reducing waste, and supporting policies that prevent illegal logging. Educating communities about the importance of forests also plays a key role in their protection.
5. What role do forests play in climate change mitigation?
Ans. Forests play a significant role in climate change mitigation by acting as carbon sinks. They absorb carbon dioxide from the atmosphere, which helps reduce greenhouse gases and combat global warming, thus contributing to a healthier planet.
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