Notes of chapter: Conservation of Plants and Animals are presented below. Indepth notes along with worksheets and NCERT Solutions for Class 8.
Forest is a large area covered with trees, gives shelter to many animals, birds and many other living organisms. A fresh and cool breeze blows in forests.
The clearing or cutting of trees of forests is called deforestation. The forest land is than use for other purposes.
Purposes to cut trees are mentioned below-
(i) Construction of road
(ii) Construction of buildings
(iii) Industrial development
(iv) Increasing demand for wood in making furniture and use as fuel.
(v) Needs more space for grazing of animals
(vi) Severe droughts and forest fires are some natural causes for deforestation.
(vi) Trees also cut for paper making. According to an assessment 17 full grown trees used in making one tone paper. Thus, we should recycle them.
(3) Consequences of the deforestation-
(i) Deforestation increases temperature and pollution level on the earth.
(ii) Trees absorb carbon – di oxide and release oxygen. But after cutting trees, level of carbon – dioxide increases in the environment. It leads to global warming as carbon dioxide traps the heat rays reflected by the earth.
(iii) The trees of forest cause rain and rain water seeps in to the earth. Thus, ground water level increases. But in absence of trees less or no rain fell. It results in decrease of ground water level.
(iv)Increasing temperature of the earth and disturbed water cycle that causes droughts on the earth.
(v)Desertification is a process in which fertile land converts in to dessert. Due to deforestation upper fertile layer of the soil removed by soil erosion and hard lower layer comes up which has less humus and less fertility. With the passage of time, fertile land gets converted into dessert.
(vi) Deforestation also causes flood. Water holding capacity of the trees lower down, it causes floods.
(vii) The other properties of the soil as nutrients, content and texture etc. also changes because of the deforestation.
(viii) Wild animals lose their homes.
(ix) Some times animals die due to temperature rise and lack of water. They have to wander from one place to another place in search of water when temperature is high . Therefore, some of them lose their lives in transferring themselves.
(x) Herbivore animals do not get food due to cutting of trees and carnivore animals also do not get food as animals begin to die due to deforestation.
(4)Conservation of forest and wildlife-
Government agencies take care of the forest and animals by making policies and providing fund for the project. The government also protects animals by notifing land as national parks, biosphere reserve, wildlife sanctuaries etc.
(i) Biosphere reserves are the areas which conserve the biodiversity and culture of the area. A biosphere reserve may also contain other protected areas in it. India has 18 biosphere reserves sites.
Eg:- The Panchmari Biosphere Reserve consists of one national park named Satpura and two wildlife sanctuaries named Bori and Panchmari.
Disturbing factors of biodiversity-
(a) Some of rare spices are living in forests. Some human killed animals for their skin. These skins of animals smuggled to other places for getting good money in return. Hunting of animals is the most dangerous factor which disturbs biodiversity.
(b) The local residents of the biosphere reserve leave their domestic animals for grazing. Sometimes it causes over grazing which reduces productivity and biodiversity of the land.
(c) Cutting of wood for fuel and for constructing houses is another reason for disturbing factor of biosphere. Many animals live on the trees and take shelter under the trees. They lost their homes after cutting trees which results in biodiversity.
(ii) A place selected by the state government to protect the animals where killing of the animals is strictly prohibited and animals is protected by providing them suitable living conditions is called wildlife sanctuary. Some restricted human activities are allowed in this area.
Eg:- Panchmari Wildlife Sanctuary
Some of the animals are listed below which are protected in the wild life sanctuary
(a) Black buck
(b) White eyed buck
(d) Golden cat
(d) Pink headed duck
(f) Marsh crocodile
(g) Rhinoceros etc.
(iii) National park-
National Park is a place where flora, fauna, landscape and historic objectives of the area is protected by the government. No human activity is allowed in this area.
Eg:- Satpura National park is a first reserve park of India. It has 55 rock shelters with rock paintings of animals and men fighting, hunting, dancing.
Some endangered animals are conserve in these parks by the government to launch different projects for different animals.
Eg:- Project tiger, project elephant, project rehinoceros etc.
Humans are killing not only big but small animals also. They are killing snake, lizards, rabbits, frogs for their different purposes. But these animals are very necessary for the ecosystem. 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.
(5)Flora and fauna-
The plants and animals found in a particular area are termed as flora and fauna of that area.
Eg:- List of flora are given below:-
(v) Silver ferns etc
List of the fauna are given below:-
(iv) Cheetal etc.
The animals and plants which are found naturally in the specific area only are called endemic species. These can be endemic to a zone, state or a country.
Eg:- Endemic flora are sal and wild mango in Panchmari biosphere.
Endemic fauna are bison, Indian giant squirrel in Panchmari biosphere
Spices is a group of the population which have common characteristics and are capable of reproducing of their of springs only with the members of their own species and not with members of any other species.
(7)Red data book-
Red Data Book is a record book which keeps data about the population of endangered plants and animals in separate books.
The movement of any species from their own habitat to other places for a particular time period for specific purposes like breeding is known as migration.
Eg:- Birds migrate to Keoladevo National Park every year in month of October and move to their own habitat in February.
Painted storke (Migratory bird), Kelodevo bird sanctuary, Bharatpur
Reforestation is the restocking replanting the trees again. It happens naturally in forests. But, a great damage is happened to our forests which can not be restore by natural restocking. Therefore, human should plant trees in the forest for our health and lives.