Our Environment Class 10 Notes

Our Environment Class 10 Notes is an informative article that presents the key concepts and ideas related to the environment for class 10 students. The article aims to provide a comprehensive understanding of the environment and its components, the impact of human activities on the environment, and the measures that can be taken to conserve and protect it. By using active voice, the article engages the reader and makes the content more interesting and interactive. It is an essential read for students who want to learn about the environment and its significance in today's world.

The waste materials produced by various activities of humans and animals, which can be divided into two main groups, are poisonous to some extent. These groups include biodegradable and non-biodegradable wastes. The environment comprises physical surroundings such as air (or atmosphere), water bodies, and soil (land) with all its organisms, including plants, animals, and micro-organisms such as bacteria and fungi (known as decomposers).

Biodegradable Wastes -Our Environment Class 10 Notes

Living organisms such as fungi, bacteria, and other microorganisms decompose substances through biological processes, which are known as biodegradable. The decomposition of biodegradable substances is influenced by temperature and sunlight. Some examples of biodegradable substances include food waste, tree leaves, urine and fecal matter, agricultural residue, sewage, paper, wood, cloth, and cow dung.

Non-Biodegradable Wastes - Our Environment Class 10 Notes

Substances that are not broken down by biological
processes. These substances may be in solid, liquid or gaseous form. These substances are inert and simply persist in the environment for a long time or may harm the various members of the ecosystem.
For Examples: These includes DDT (Di-chloro-di phenyl trichloro ethane-in-pheneyle the cheoro ethane), insecticides, pesticides, mercury, lead, arsenic aluminum, plastics, polythene bags, glass, radioactive wastes. These non-biodegradable wastes are major pollutants of the environment

Biodegradable and non-biodegradable substances have harmful effects on the environment, such as destroying natural beauty and making the surroundings dirty. The decomposition of these wastes produces a foul smell, which spreads to the surrounding areas. Non-biodegradable substances may block drains and create pools of waste, which become breeding sites for mosquitoes. These mosquitoes can carry diseases such as malaria and dengue, which can be transmitted to humans.

Difference between Biodegradable and Non-Biodegradable wastes

An ecosystem comprises living things such as plants, animals, and decomposers, as well as their non-living environment, including soil, air, and water. Examples of ecosystems include forests, ponds, lakes, and green lands. In an ecosystem, there is a continuous exchange of energy and matter between living and non-living components. Ecosystems can be natural or man-made. Grasslands, forests, seas, rivers, deserts, mountains, ponds, and lakes are examples of natural ecosystems. The terrestrial ecosystem (land-based ecosystem) comprises the desert, grassland, and mountains, while the aquatic ecosystem (water-based ecosystem) comprises ponds, rivers, lakes, and seas. Man-made or artificial ecosystems include gardens, crop fields, parks, and aquariums.

Components of Ecosystem - Our Environment Class 10 Notes

The biotic component and abiotic component are the two components of an ecosystem. The biotic component includes three types of organisms:

1. Producers: All green plants and blue-green algae can produce their food (sugar and starch) from inorganic substances using light energy through photosynthesis. They are also known as autotrophs. Therefore, all green plants are called producers. There are two types of planktons: phytoplanktons and zooplanktons. Phytoplanktons are microscopic aquatic plants that float freely on the surface of water, while zooplanktons are microscopic aquatic animals that float freely on water. Freely floating protozoa are an example of zooplankton.

2. Consumers: These are organisms that consume other organisms or their products as their food. All animals belong to this category. Consumers depend on producers for their food either directly or indirectly. They get their food by eating other organisms or their products. Common consumers include man, goat, deer, fish, lion, cow, buffalo, etc. Consumers can be classified into four types:

• Herbivores
• Carnivores
• Parasites
• Omnivores

(i) Herbivores directly eat producers (plants) for their food. They are also known as first order consumers. Common examples of herbivores include deer, rabbits, rats, squirrels, goats, and cattle.

(ii) Carnivores consume other animals and feed on the flesh of herbivores. They are also known as primary carnivores or second order consumers. Examples of carnivores include snakes, wild cats, jackals, frogs, birds, and fishes. Some carnivores are preyed upon by second order carnivores or third order consumers, such as owls, peacocks, tigers, and lions. Carnivores that are not preyed upon further are called top carnivores, for example, lions.

(iii) Omnivores are organisms that feed on both plants and animals. Human beings are a common example of omnivores because they eat both plants (e.g. pulses, grams, oilseeds, fruit) and animal products (milk, meat, eggs).

(c) Decomposers are fungi and bacteria that decompose dead plants and animals into simpler compounds. They are also known as microorganisms or saprotrophs and are called reducers. Decomposers play an important role in the ecosystem by replenishing natural resources.

 Abiotic Components -Our Environment Class 10 Notes

Abiotic components of an ecosystem consist of non-living components such as the physical environment, edaphic factors like soil texture, topography, water, and air, inorganic substances like carbon dioxide, nitrogen, oxygen, water, phosphorus, sodium, potassium, and calcium which are involved in the cycling of materials in the ecosystem, and organic compounds like proteins, carbohydrates, and lipids that form the living body and link the abiotic and biotic components. Climatic factors such as sunlight, temperature, pressure, humidity, and rainfall affect the distribution of organisms in the ecosystem.

The ecosystem performs various functions such as indicating the available solar energy and the efficiency of trapping the same, providing information about the available essential minerals and their recycling periods, giving knowledge about the web of interactions and inter-relationships among the various populations as well as between the population and the abiotic environment, helping human beings to know about conservation of resources, protection from pollution, and inputs required for maximizing productivity. Two processes of energy flow and biogeochemical cycles proceed side by side in the ecosystem. The energy flow is unidirectional while the movement of nutrients is cyclic.

A food chain is a sequence of living organisms in a community in which one organism consumes another organism to transfer food energy. It represents the arrangement of different biotic groups in a sequence of energy transfer, including producers, herbivores, and carnivores. The transfer of energy takes place in only one direction. The study of food chains helps in understanding food relationships and interactions among the various organisms in an ecosystem, and they transfer energy and materials between various living components. The food chains give dynamicity to an ecosystem. The movement of toxic substances like pesticides, weedicides, etc., through food chains can prove very harmful.

Examples of food chains operating in a grassland or forest include grass (producer) → deer (herbivore) → lion (carnivore) and grass (producer) → insect (herbivore) → frog (carnivore) → eagle (secondary carnivore).

Food Web

The term "food web" refers to the interconnected network of food chains that establish relationships between various species in an ecosystem. In a food web, a single organism may occupy multiple positions in different food chains. This means that an organism can obtain food from various sources and can be consumed by different types of organisms.

Trophic Levels

The food chain consists of different trophic levels that facilitate the transfer of energy or food from one level to another. As we move up the trophic levels, there is a gradual decrease in the amount of energy transferred from one level to the next in a food chain.

Only 10% of the energy is transferred to the next trophic level, while the present trophic level utilizes 90% of the energy in its life processes.

Below are the various trophic levels:

The first trophic level consists of the plants or the producers. The second trophic level is formed by the herbivores or primary consumers. The third trophic level is composed of carnivores or secondary consumers. The fourth trophic level consists of the large carnivores or the tertiary consumers, which feed upon the small carnivores.

Ten percent law

Ten percent law states that only 10 percent of the energy entering a particular trophic level of organisms is available for transfer to the next higher trophic level.For example, Suppose 1000 J of solar energy is received by green plants, then only 1% of solar energy available on earth is utilized by plants. So only 10 J (1% of 1000 J) is trapped by plants and the rest 990 J of energy is lost to the environment. So, plants utilizes only 10 J of energy. Next, only 10% of the 10 J energy of plant, that is, 1 J, is available to the herbivore animal while 9 J is lost to the environment. Again, just 10% of the 1 J of energy of herbivore animals is utilized by carnivore animals. Thus, carnivore animals have only 0.1 J of energy while 0.9 J is lost to the environment.

Environmental Problems: Changes in the environment affect us and our activities change the environment around us. This led to the slow degradation of the environment that arose many environmental problems. For Example; depletion of the Ozone Layer and waste disposal.

Depletion of Ozone Layer: Ozone (O3) layer is largely found in the stratosphere which is a part of our atmosphere from 12 km -50 km above sea level. This region is called ozonosphere. Ozone is deadly poisonous at the ground level.

The Earth's protective blanket, the ozone layer, absorbs most of the harmful U.V. (Ultraviolet) radiation of the Sun, protecting living beings from health hazards such as skin cancer, cataract in eyes, a weakened immune system, and destruction of plants. In 1985, the decline of the ozone layer thickness in Antarctica was first discovered and was termed as OZONE HOLE.

To limit the damage of the ozone layer, the excessive use of CFCs (Chloro Flouro Carbon), a synthetic, inert chemical, for example, Freon, which are used as refrigerants and in fire extinguishers, caused ozone depletion in the upper atmosphere. A single chlorine atom can destroy 1,00,000 ozone molecules. The United Nations Environment Programme (UNEP) did an excellent job in forging an agreement to freeze CFC production at 1986 levels (KYOTO Protocol) by all countries.

Garbage Disposal: Industrialization and rise in demand of consumer goods have created a major problem in the form of wastes/garbage accumulation and its disposal especially in urban areas.
The disposal of waste should be done in a scientific way. There are different methods of waste disposal. 

The increase in concentration of harmful chemical substances like pesticides in the body of living organisms at each trophic level of a food chain is called biological magnification.

Industrialization and the increasing demand for consumer goods have led to a significant issue of waste accumulation and disposal, particularly in urban areas. It is important to dispose of waste in a scientific manner, and there are several methods available depending on the nature of the waste.

One such method is incineration, which involves burning waste at high temperatures to form ash. Incineration is commonly used to destroy household, chemical, and biological waste in an incinerator.

Another method is open dumping, which is a traditional way of dumping solid waste in selected areas of a town. However, this method can cause pollution and is not environmentally friendly.

Land filling is also a method of waste disposal, where waste is dumped in low-lying areas and compacted by rolling with bulldozers.

Composting is a natural process that involves filling organic waste into a compost pit (measuring 2m x 1m x 1m) and covering it with a thin layer of soil. After approximately three months, the garbage inside the pit changes into organic manure.

Recycling is another method where solid waste is broken down into its constituent materials, which are then used to make new items. Even non-biodegradable solid wastes like plastic and metal can be recycled.

Finally, reusing items is a simple and conventional technique that involves using an item repeatedly. For instance, paper can be reused to make envelopes, among other things.

Conclusion

In conclusion, the Our Environment Class 10 Notes provide a comprehensive understanding of the various aspects of the environment, including its components, functions, and challenges. These notes emphasize the importance of protecting and preserving our environment for a sustainable future. By studying these notes, students can gain insights into the interdependence of different components of the environment, and how human activities can impact the natural balance. Furthermore, the notes provide practical solutions to environmental problems, encouraging students to take action to protect the environment. Overall, the Our Environment Class 10 Notes are an essential resource for students looking to deepen their understanding of the environment and become responsible stewards of our planet.

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Our Environment Class 10 Notes