Class 10 MAHARASHTRA STATE TEXTBOOK BUREAU Solutions Science Chapter 4 - Environmental Management

Correct food chain:

Paddy field → Grasshopper → Frog → Snake → Eagle

The above food chain is seen in the terrestrial ecosystem.

It mentions about paddy field, so the food chain must be operating in the vicinity of coastal lands. There is water logging in the paddy fields. Therefore, it offers an ideal habitat for the frogs.

In the above example, paddy fields act as producers in the ecosystem. Grasshoppers act as primary consumers, frogs are the secondary consumers, snakes are the tertiary consumers and eagles constitute the apex consumers. At every trophic level, the bacteria, fungi and some scavenging worms act as decomposers.

In this ecosystem, the solar energy is captured by the paddy fields and transferred from one trophic level to another in a step wise manner.

• The given statement brings out the fact that the Earth belongs to everyone, from our ancestors to our future generations.
• It stresses that our planet Earth should be protected and conserved by us in the same way as done by our ancestors, so that the beauty of Earth can be passed on to our future generations.
• It highlights an underlying problem which is the overexploitation of resources by the present generation which could eventually lead to the destruction of life on Earth.
• It is possible to protect the planet Earth for future generations by following the path of sustainable development.
• Sustainable development is a development that meets the needs of the present without compromising the ability of future generations to meet their own needs.
• It seeks to promote a judicious use of non-renewable energy sources such as coal and petroleum so that they do not get exhausted and remain unavailable for our future generations.

Environmental Conservation

• The Earth faces several environmental problems due to natural and man-made activities. These problems affect the existence of various living organisms.
• In order to protect these organisms and maintain environmental balance, there is a need for environmental conservation. It is essential to conserve the environment to maintain the quality of life on Earth.
• In order to conserve the environment, the Government has formulated several acts and rules. UN has established UNEP for the environment conservation programs.
• It is important that people actively participate in such conservation movements. Conservation of the environment is the social responsibility of every individual.
• Judicious use of natural resources is also a way of conserving the environment.

Chipko Movement of Bishnoi:

• The Bishnoi community is located in Khejarli or Khejadli village in Rajasthan. The name of this village is derived from the Khejri trees.
• The first event of Chipko Movement took place in Khejadli village in 1730 AD. In this village 363 Bishnois, led by Amrita Devi sacrificed their lives for protecting the Khejri trees, which are considered sacred by the Bishnoi.
• Amrita Devi along with her three young daughters Asu, Ratna and Bhagubai were killed with the axes that were brought to cut the trees.
• 83 Bishnoi villages came together and the villagers sacrificed their lives after hearing about Amrita Devi's sacrifice. 363 Bishnois were killed as they opposed the king from cutting the trees.
• As the king realised his mistake, he ordered to stop the further felling of trees. He issued a royal decree to protect the trees and wild life in the area.
• Chipko movement of the 20^th century in Uttar Pradesh also followed the same pattern of embracing the trees and saving them from cutting.

Biodiversity

• Biodiversity includes the diverse life forms that inhabit a particular area.
• Biodiversity is seen due to variety of life forms and different ecosystems that are occupied by these organisms.
• In nature, there is a biodiversity at three different levels, viz. genetic diversity, species diversity and ecosystem diversity.
• This implies that there is a diversity in the individuals belonging to the same species due to genetic reasons, and also among the different species. There is a diversity in the ecosystems that are present in any region.
• However, this huge biodiversity is threatened due to development of mankind. There are special efforts taken to restore the lost and threatened biodiversity.
• Some of these include the establishment of sanctuaries, National Parks, biodiversity hotspots and biosphere reserves. Certain endangered species are protected by carrying out conservation projects using gene banking.

Sacred groves

• Sacred grove is a green patch of the forest which is conserved by the local people in the name of God.
• This area does not belong to the forest department. It resembles a sanctuary that is conserved by the common people and tribals in the area.
• These people believe that God or deity resides in the sacred groves. Hence in local language, they are known as Deorai.
• As a result, people do not fell trees in this area. Also, hunting of wild life is strictly prohibited.
• More than 13000 sacred groves have been reported in India. Most of these are in the Western Ghats in Maharashtra, Karnataka and Kerala.
• Sacred groves are rich in the flora and fauna. They have a crucial role in conserving biodiversity.

Disaster and its management

Disaster is a disruption on a massive scale, either natural or man-made, occurring in short or long periods.

Disaster management refers to the measures taken for the safety and protection of life and property from natural or man-made disasters.

Objectives of disaster management:

• To save human life from disasters and help them in moving away from the disaster location by rapid action.
• To supply essential commodities to the affected people. This helps to reduce the gravity of the disaster. People are given grains, water and clothes and other basic necessities under this objective.
• To restore normalcy in the lives of the people affected by disasters.
• To rehabilitate the affected and displaced victims.
• To think and execute protective measures in order to develop capability to face the disasters in future.

• The major cause of environmental damage is pollution. Pollution of air, water bodies and soil contribute to various environmental problems.
• Continuous increase in pollution has made the environment nearly unfit for survival. This can largely be attributed to the rapid rate at which trees are being cut. In the absence of trees, the level of carbon dioxide in the atmosphere increases, adding to the problem of global warming.
• Moreover, the emission of carbon monoxide, hydrocarbons and other such gases, from vehicles and factories, is rapidly polluting the air making it even difficult to breathe.
• Pollution of water bodies have resulted in the death of aquatic life and making most of the water bodies unfit for human and animal use.
• Pollution must be controlled in order to have a good quality environment. For example, when plastic is thrown anywhere, it causes pollution of land, clogs the drains and even affects the feeding of animals.
• Plastic pollution can be completely stopped through proper management of plastic waste by reusing or recycling techniques. This would be a powerful way of environmental management.
• Similarly, when we reduce pollution of different types, we automatically help to regain environmental health.

Initially, assessment of the environmental problems will be done. The nature and severity of these problems will be understood by a detailed study of the environment. Accordingly, the projects can be undertaken to combat these problems.

1. Tree plantation is one such easier project that can be undertaken to conserve the environment. The further nurturing of the tree will also be our responsibility. Local and sturdy varieties of trees will be selected for tree plantation. Such trees can survive even in polluted environment and the pressure of urbanization.

2. Solid waste management is another very important project that should be undertaken by every society, colony or school. Segregation of wastes into dry and wet wastes followed by its proper disposal will be taught to all the people in the neighbouring area.

3. Another very significant project is to ban plastic and make people aware about the harmful effects of plastic. They can be convinced to adopt re-use techniques or send the plastic to recycling units.

4. Fossil fuels are non-renewable and polluting. Therefore, their use should be reduced as far as possible. Using a bicycle, or walking down for shorter distances or using public transport are some better alternatives for saving the use of fossil fuels. The awareness drive about these facts will be taken up as a project.

5. Taking care of stray animals, providing them shelter, feeding endangered birds like sparrows and allowing them to survive with our support is also one of the essential acts to conserve animal species.

6. Attempts will be made for bringing awareness among the minds of everyone. Such small acts can bring about a major shift in the attitude of the people. This will certainly help in environmental conservation.

Factors affecting the environment:

• The biotic as well as the abiotic factors affect the environment.
• Abiotic factors are either natural or man-made. Among the abiotic factors, the physical and chemical factors can alter the conditions of the environment.
• The various interrelationships between different living organisms can also affect environment.
• Natural disasters such as earthquakes, forest fires, cyclones, cloud bursting and drought change the environment.
• Human activities such as deforestation, urbanisation and construction cause permanent damage to the ecosystems. Due to man-made impact, there can be large scale changes in the environment.

• Human beings appeared last on the Earth in the history of evolution of animals. However, due to his intelligence, imagination, critical thinking and memory, he made progress in all fields. By the virtue of his qualities, man became the supreme.
• All natural resources on the Earth were very rapidly exploited by man for his benefits.
• Under the pretext of technology and development, he degraded almost all natural ecosystems.
• He never obeyed the rules of nature for his own selfish gains.
• Man is solely responsible for pollution, urbanization, industrialization and deforestation.
• Hunting and poaching of animals contributed to the extinction of many animals.
• Except man, no other organism on the Earth can change the ecosystems in such a drastic way.
• Therefore, it is rightly said that human beings have an important place in the environment.

Biodiversity exists at the following three levels, viz. genetic diversity, species diversity and ecosystem diversity.

1. Genetic Diversity: Diversity seen among the organisms of same species due to genetic differences between them is called genetic diversity. E.g. Every individual human being is different from the other. No two animals or plants are exactly alike.

2. Species Diversity: Differences between the different species of organisms is the species diversity. E.g. Different species of plants, animals and microbes differ from one another.

3. Ecosystem Diversity: In one region, there may be different ecosystems, which is referred to as ecosystem diversity. Ecosystems are natural or artificial. Every region shows different types of ecosystems such as aquatic, terrestrial, desert or forest ecosystems. Each ecosystem has its own habitat with resident flora and fauna.

Biodiversity can be conserved in the following ways:

• Protection of rare species of plants and animals.
• Creating habitats for animals and plants by establishing National Parks and sanctuaries.
• Declaration of bioreserves, the areas which are protected through conservation.
• Conservation projects for protecting special species.
• Conservation of flora and fauna.
• Strict observance of acts and rules.
• Use of traditional knowledge and maintaining a record of traditional knowledge.

• Jadav Molai Payeng was a common man, a simple forest worker. But he had great knowledge about plants and tree plantations.
• He single-handedly planted thousands of trees. He worked continuously to grow these plantations and thus, converted a barren patch of land into a forest spread over 1360 acres.
• He has shown that a single determined person can establish a new forest.
• We understand the values of hard work, sincerity and devotion to the nature through the story of Jadav Molai Payeng.
• Even a common man can contribute a lot for the conservation and protection of the environment by learning from the story of Payeng.

Biodiversity hot spots

• 34 highly sensitive biodiversity spots are reported in the entire world. These hotspots occupied 15.7% area of the Earth.
• However, currently about 86% of the sensitive areas are already destroyed. Now about 2.3% area of the Earth still has such sensitive biodiversity spots.
• There are 1,50,000 plant species in these areas which constitute about 50% of the species in the world.
• In India, out of 135 species of animals, 85 species are found in the jungles of Eastern region.
• There are about 1,500 endemic plant species in the Western Ghats.
• About 50,000 plants species out of the total plants in the world are said to be endemic.

Reasons for endangering species of plants and animals

• Certain natural disasters like earthquakes, climate change, forest fires, drought and cyclones also affect the living organisms due to lack of food and water.
• The animals and plants species are endangered majorly due to man-made causes particularly due to hunting and poaching.
• Animal-human conflicts occur due to invasion of human settlements into the habitats of wild animals.
• Construction of dams, roads, and colonies destroy the habitats of wild life.
• Industrialization, urbanization and population explosion put tremendous pressure on the existing biodiversity.

Measures to save the endangered species

• In order to save and protect the biodiversity, many scientists and naturalists come together. A stretch of land is protected by declaring it as a sanctuary or a National park by the Government. Even the locals can protect such a land as a sacred grove.
• Various acts and rules have been formulated to protect the organisms. The violators of such rules are punished accordingly.

The given symbols inculcate the importance of being eco-friendly.

Symbol A gives the message, "Reduce, reuse and recycle". This is an important mantra for the utilization of natural resources. It is essential to maintain the natural resources by reusing and recycling them. As far as possible, one should reduce the excessive use of resources by preventing consumerism.

Symbol B gives the message "Save water". Water problems persist in many major cities and villages. In villages it results in drought-like conditions. This severely affects the agricultural produce. Therefore, the message for saving water or to make judicious use of water should be spread far and wide

Symbol C advocates the "Use of solar energy". Solar energy is a renewable energy alternative which is very easily available in a country like India. By using solar energy, we can replace the polluting and exhaustible fuels. Thereby, pollution will also be reduced.

Such symbols help to spread the message of environment conservation so that people can change themselves and adopt eco-friendly measures to save the environment.