Welcome to Class 8 Science chapter 7 notes. On this page, you will find notes, questions, and answers to class 8 science chapter 7. These Conservation of Plants and Animals Class 8 notes, explanations, examples, and questions and answers are according to CBSE and the NCERT textbook. If you like the study material, feel free to share the link as much as possible.
A large variety of plants and animals found on our planet. They both depend on each other for survival. So, we need to conserve biodiversity as it helps in balancing the ecosystem.
Conservation can be defined as the protection and maintaining of diversity of species (plants and animals).
Conservation includes the protection of species from extinction and restoring habitats, preventing deforestation and enhancing ecosystems.
Today, a major threat to survival of mankind is deforestation.
Deforestation
The term deforestation can be defined as the act of massive cutting down of trees and clearing of forests to use the land for agricultural purposes. Deforestation disturbs the balance in nature. If cutting of trees continues, rainfall and the fertility of the soil will decrease.
Deforestation (image source canva)
Reasons or causes of deforestation
Rapid urban development
Setting up industries
Agricultural related purposes
Making furniture
Using wood as a fuel.
Natural causes such as Forest fires, Droughts, Acid rains and Volcanic eruptions.
Figure below shows the points you must remember for the causes/reasons of deforestation
Reasons of Deforestation
Consequences of deforestation
Deforestation causes severe impact on the environment such as
Loss of habitat This leads to the extinction of many of species. Due to deforestation forests are vanishing due to animals are losing their habitat.
Rise in temperature The increase in temperature on the earth disturbs the water cycle and may reduce rainfall which cause drought.
Depletion of ground table.
Global warming Plants absorb carbon dioxide from the environment for the purpose of photosynthesis but due to deforestation the amount of carbon dioxide has increased in environment due to which global warming has increased. Increased global warming has disturbed rainfall patterns.
Less exchange of gases between green plants and the environment.
Desertification Deforestation increases the soil erosion which leads to deterioration of fertile land. Soil erosion is the removal of top layer of the soil and exposes the lower, hard and rocky layers which contain less humus and is less fertile. Gradually, the fertile land gets converted into infertile (barren) land or wasteland. So, desertification can be defined as a gradual conversion of fertile land into wasteland.
Biodiversity
The variety of living organisms like plants,animals and micro-organisms is called biodiversity. In other words it refers to the vast variety of life on Earth. Any living thing, including plants, bacteria, animals, and humans, is included in the term biodiversity.
Conservation of biodiversity
The conservation of biodiversity is important as it maintains the ecological balance on the earth. It also maintains the soil fertility or prevents soil erosion.
What is meant by biodiversity conservation?
The protection, restoration, and management of ecosystems and natural environments, as well as ensuring that they are safe and functional, are all part of biodiversity conservation.
How can we conserve biodiversity
Biodiversity can be conserved by
Not cutting trees.
Not hunting animals.
Utilizing natural resources in a cost-effective manner.
Creating protected areas for animals like wild life centuries, where no human activities are permitted.
Flora and Fauna
Some plants and animals are found in particular areas.
They may not exist naturally in other locations.
The 'plants' that grow naturally in a specific area are referred to as the 'flora' of that area. Teak, Jamun, Fern, (Sal) Mango and Arjun are the flora of Pachmarhi Biosphere Reserve
And the 'animals' that live naturally in a specific area are referred to as the 'fauna' of that area.
Thus, flora and fauna refer to plants and animals that grow naturally in that region. Cheetal, Wolf, Leopard, Chinkara, Blue bull, Barking deer, and Wild dog are the examples of fauna of the Pachmarhi Biosphere Reserve
<flora and fauna examples. (image source canva)
Difference between flora and fauna
Flora-
The plants found in a particular area are called flora.
Example-Peepal, sal, banyan.
Flora is non-motile (not capable of motion) and synthesize its own food.
Fauna
The animals found in a particular area are called fauna.
Example-Deer, Panda
Fauna is motile (capable of motion) and can move from one place to another for food.
Species
Organisms that resemble one another having common characteristics and are able to breed among themselves are called a species. Species is a group of population which are capable of interbreeding. Members of species have common characteristics.
Wildlife species on the basis of being threatened or extinct are being classified into different categories such as
Endemic species
Extinct species
Endangered species
Threatened species
Endemic Species:- Those species which are restricted to a particular region or area are called endemic species. For example-Tree like sal and animals like gibbon.
Extinct species:- Those species which no longer exists anywhere on the earth are called extinct species.
Endangered species:- Those species which are on the urge of extinction are called endangered species. For example-Leopard, Giant panda. Habitat Destruction is the main reason that many species are becoming endangered.
Threatened species:- Those species which are in danger of extinction are called threatened species. For example- Black buck, elephant.
Migration
It can be defined as a movement of a species from its own habitat to another habitat.
Several species of birds, fish, deer, monarch butterflies, green turtles move from one region to another
With weather changes (especially cold) for food, breeding and to avoid unfavourable conditions.
In India, migratory birds from the Arctic and northern regions are found.
They have a natural habitat in Siberia which is a very cold place.
When the winter ends, the Siberian cranes fly back to their homeland.
Ecosystem
The biotic factors such as (plants, animals and humans) and Abiotic factors (soil, water, air) together constitute the ecosystem.
The various living organisms in an ecosystem interact with one another (via food chains) as well as with the physical environment in which they exist.
An ecosystem is an autonomous unit of live organisms and a non-living environment, which only requires sunlight to function.
Importance of forests
Forests are of great importance to the living beings. Given below are some of the points that shows how important forests are for mankind
Forests aid in the conservation of biodiversity.
Forests are naturally occurring environments for a variety of plants and animals.
Forests provide a variety of resources such as timber, wood, food, medicines, and fodder.
Forests contribute to the preservation of ecological balance.
Forests contribute to the regulation of climate and rainfall.
Forests aid in soil erosion prevention and flood protection.
Forests play an important role in providing the oxygen to the world.
Need of conservation of species
To protect the plant and animal species from being extinct there is a need for conservation. Some of the reasons for the need of conservation of species are
To maintain and preserve the eco-system.
The genetic diversity must be sustained.
The growth of tourism which might help to keep the economy growing.
Food resource conservation.
Medicinal use for human benefit.
To preserve endangered, uncommon, and vulnerable species.
Red Data Book
Based on the risk of endangered and extinction, the IUCN (The International Union for the Conservation of Nature and Natural Resources) maintains a list in a book called the Red Data Book which classifies animals and plants into different groups. Red Data Book keeps a record of all the endangered animals and plants. Red Data Book is maintained internationally by an organism. Our country also maintains Red Data Book for plants and animals.
Project Tiger
Project Tiger was launched in the country by the government in 1973 to protect the Bengal Tiger. The objective of this project was to ensure the survival and maintenance of tiger population. Project Tiger's main aims are to:
Reduce the factors that contribute to tiger habitat loss and reduce them by appropriate management.
The habitat damage must be repaired to the greatest degree possible in order to promote the ecosystem's recovery.
Maintaining a viable tiger population is important for economic, science, cultural, aesthetic, and ecological reasons.
Conservation of forests and wildlife
For conservation of forests and wildlife, the government has set up protected areas such as-wildlife sanctuaries, national parks, biosphere reserve and biodiversity parks. Cultivation, grazing, cutting trees, hunting and poaching are strictly prohibited in these protected areas.
1. Wildlife Sanctuary
It is an area in which wildlife is protected in which hunting is prohibited.
There are 553 wildlife sanctuaries found in India.
People living in wildlife sanctuaries are allowed to do certain activities such as grazing by their livestock, collecting medicinal plant, firewood etc.
It is important to note here that there is a difference between a wildlife sanctuary and a zoo.
Zoo is an artificial habitat whereas wildlife sanctuary conserves the natural habitat of animals. Zoos are the places where animals receive protection.
2. National park
An area created by the government for the preservation of the natural environment. National park preserves flora, fauna and landscape. There are more than 100 national parks in India. Satpura National Park is the first reserves Forest of India.
3. Biosphere Reserve
A large protected area of land meant for the conservation of wildlife biodiversity and traditional lifestyles of the tribes living in that area. India has around 18 biosphere reserves to conserve vast swaths or areas of natural habitat.
Reforestation
Reforestation is the opposite of deforestation.
Reforestation can be defined as the process of replanting trees and recreation of forests which have been destroyed in the past.
For this people should be encouraged to plant more and more trees.
Reforestation can take place naturally also. If the deforested area is left undisturbed, it re-establishes itself.
In India we have the Forest Conservation Act. This act is aimed at preservation and conservation of natural forests and meeting the basic needs of the people living in or near the forests.
Recycling of paper
Recycling of paper refers to the process by which waste papers can recycled for reuse.
Recycling one tons of paper can save around 17 fully grown trees from being cutting down and also saves landfill space.
It saves energy.
The amount of harmful chemicals used in paper making will also be reduced.
Summary
Here is conservation of plants and animals class 8 notes summary
The preservation and protection of the diversity of species (plants and animals) can be referred to as conservation.
Deforestation is the widespread removal of trees and forests in order to make space for agriculture.
A component of biodiversity conservation is making ecosystems and natural surroundings safe and functional through maintenance, restoration, and management.
For the purpose of photosynthesis, plants take in carbon dioxide from their surroundings; however, as a result of deforestation, the amount of carbon dioxide in the atmosphere has increased, contributing to an increase in global warming.
With changes in the weather (particularly cold), many species of birds, fish, deer, monarch butterflies, and green turtles migrate from one area to another for food, breeding, and to avoid unfavorable conditions.
The government has established protected areas including wildlife sanctuaries, national parks, biosphere reserves, and biodiversity parks in order to preserve forests and wildlife.
