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Concept:

• Crop rotation is the practice of planting different crops sequentially on the same plot of land to improve soil health, optimize nutrients in the soil, and combat pest and weed pressure.
• Mixed farming is the one in which crop production is combined with the rearing of livestock.
• The livestock enterprises are complementary to crop production so as to provide a balanced and productive system of farming.

Explanation:

When the same crop is grown over and over again on the same field, the essential nutrients of the soil necessary for the production is exhausted which leads to infertility of the soil.

To make the soil healthy and ecologically balanced we should practice-

Cropping Pattern:

• Mixed cropping is growing two or more crops simultaneously on a piece of land, this reduces risk and if the insects and some microorganisms attack anyone's crop the two crops also get spoiled, and is difficult to spray pesticides to crops.
• Intercropping is the growing of two or more crops simultaneously on a piece of land in definite patterns. This method of cropping can give a better yield.

Concept:

• A source of energy is that which is capable of providing enough useful energy at a steady rate over a very long period of time.
• Source of energy are usually classified either as:
• Renewable source of energy
• No n-renewable source of energy

Geo-Thermal Energy

• Geothermal Energy is the energy obtained from heat stored in the earth crust and used for various purposes like electricity generation or direct heating applications.
• Geothermal energy is basically stored in the earth crust up to the depth of 3 to 4 km.

Explanation:

• Non-conventional sources and renewable sources of energy are those that can be regenerated naturally within a short time span, geothermal energy is one of it.
• Their use does not result in their complete exhaustion and they would not take millions of years in their formation.

There are basically two sources of energy:-

Additional Information

• Geothermal Energy in India
• In India, exploration and study of geothermal fields started in 1970.
• The GSI (Geological Survey of India) has identified 350 geothermal energy locations in the country.
• The most promising of these is in Puga valley of Ladakh.
• The estimated potential for geothermal energy in India is about 10000 MW.
• The major sites for geothermal energy are:
• Himalayas: J&K, HP and Sikkim; PUGA hot spring in J&K and Manikaran in HP.
• Sohana: Haryana, Rajasthan.
• Son-Narmada-Tapi (SONATA): MP, Chhattisgarh and Jharkhand; Tattapani spring in Chhattisgarh.
• Cambay: Mainly Gujarat and some parts of Rajasthan
• Godavari: AP
• Mahanadi: Orissa, Taptapani Spring in Orissa.

The correct answer is Chilika Lake.

Explanation:

The largest brackish water lagoon Chilika lake situated in Odisha.

Lake Chilika is the largest brackish water lagoon in Asia and the second largest coastal lagoon in the world.

• It spread across the Puri, Khurda and Ganjam districts of the state of Odisha on the east coast of India, at the mouth of the River Daya, which flows into the Bay of Bengal, covering an area of more than 1,100 km.
• It is the largest coastal lagoon in India and the second-largest brackish lagoon in the world after the New Caledonian Barrier Reef.
• It has been listed as a UNESCO World Heritage site.
• It is the largest wintering ground for migratory birds in the subcontinent of India.
• Ansupa lake, Kanjia Lake and Pata Lake are all situated in Orissa.

Additional Information

• Wular Lake is in Jammu and Kashmir and it is the largest freshwater lake in India.
• Vembanad Lake: It’s the longest lake in India and is situated in Kerala

Concept:

A resource is something that can be utilized by human in its original or modified form. 

It can be classified in the given category:

• On the basis of accessibility/stock: Renewable and Non-renewable
• Renewable resources are those which get renewed or replenished quickly.

Some of these are unlimited and are not affected by human activities, such as solar and wind energy. Yet careless use of certain renewable resources like water, soil, and forest can affect their stock.

• Non-renewable resources are those which have limited stock. Once the stocks are exhausted it may take thousands of years to be renewed or replenished.
• On the basis of Distribution: Ubiquitous and localized
• A resource that is found everywhere is a ubiquitous resource. The air we breathe is an example of a ubiquitous resource.
• A resource that is found only in certain places.is called a localized resource. A mineral like copper is an example of a localized resource.
• On the basis of origin: Biotic & Abiotic
• Biotic Resources are also known as living resources. These are renewable resources and include plants, forests, and animals. The foods, sugars, tea, coffee, medicines are obtained from the plants.
• The resources which are composed of non-living things are called Abiotic resources. Example, land, water.
• On the basis of development and use: Actual and Potential
• A resource whose quantity is known and they are being used at present. The available technology is used to use these resources. Such resources are called Actual Resource. The dark soil of the Deccan Plateau in Maharashtra, rich deposits of coal in the Ruhr region of Germany is an example of actual resources.
• A resource whose extra quantity is not known. and they are not being used at present. But when technology improves, their use in the future is possible. Such resources are called Potential Resource. The uranium found in Ladakh is an example of a potential resource.

Explanation:

• Some resources, such as minerals or oil, exist as finite stocks, which are non-renewable within an economic time frame.
• Others, such as timber or solar energy are renewable and, potentially, the flow of services from these resources can be harvested indefinitely.

So, Mineral stocks that exist on the earth surface are considered Non-renewable.

Concept:

Nuclear fission is a nuclear reaction process in which a heavy nucleus splits into two nuclei of nearly equal mass.

• Example – Uranium (235) breaks into Barium (141) and Krypton (92) with a lot of energy.

• Radioactivity: It is a type of instability of a nucleus of a particle due to this the particles releases energy or smaller particles.

• It is mostly of α, β & γ type of particles.

Nuclear fusion is the nuclear reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles.

Explanation:

• A thermal power station is a power station in which the chemical energy of conventional sources is converted into heat energy which is again converted to electric power.
• Based on the fuel used to generate steam, thermal power plants can be classified as coal, gas, diesel, and Natural gas.
• Thermal power (Coal) is the "largest" source of power in India.
• The Vindhyachal Thermal Power Station(Madhya Pradesh) is currently the biggest thermal power plant in India.
• Uranium is the fuel most widely used by nuclear plants which are also Thermal plants but are called nuclear power plants.

Explanation:

• Itai-Itai, which literally translates to ‘it hurts, it hurts’ is the name given to cadmium poisoning.
• The disease Itai-Itai is caused by Cadmium.
• This name was given to the disease by the locals of Toyama Prefecture of Japan in 1912.
• This disease was recognized as the Four Big Pollution Diseases of Japan.
• Cadmium is a naturally occurring toxic heavy metal.
• It is an extremely toxic industrial and environmental pollutant classified as a human carcinogen.
• It is used in the manufacturing of NiCd rechargeable batteries.

Additional Information

Minamata disease, sometimes referred to as Chisso-Minamata disease, is a neurological syndrome caused by severe mercury poisoning.

Explanation:

• Dengue is a mosquito-borne viral infection causing a severe flu-like illness and, sometimes causing a potentially lethal complication called severe dengue.
• Malaria is a life-threatening disease caused by parasites that are transmitted to people through the bites of infected female Anopheles mosquitoes
• Filariasis is a parasitic disease caused by an infection with roundworms of the Filarioidea type.
• This disease belongs to the group of diseases called helminthiasis.
• Spread by blood-feeding black flies and mosquitoes namely Anopheles, Culex quinquefasciatus, Aedes, and Mansonia.

NOTE - Filariasis is not only spread by female anopheles mosquitoes. It is transmitted by Culex quinquefasciatus, Aedes and Mansonia also.

• The Plague is an Infectious disease that is basically caused by Yersinia or Bacillus pestis. which is basically found in animals particularly rodents.
• It basically affects the lungs, lymph nodes, and blood vessels.
• It is also known as the "Black Death".
• The transmission of this infectious bacterial disease is through a bite of an infected rat.
• There are basically three types of plague-
• Bubonic plague
• Pneumonic Plague
• Septicemic Plague

Hence among the options Dengue, filaria are caused by mosquitos while Plague is caused by rodents.

The correct answer is CFC.

Explanation:

Human activities that affect the environment: 

The growing world affects the environment around us both in the atmosphere and the ground.

1. The Ozone layer & its depletion.
2. The management of garbage we produce.

We generate a lot of material that is thrown away. Like plastics, glasses, metals, organic waste, chemical waste etc.

Ozone Layer: 

• Ozone (O3) is a molecule formed by three atoms of oxygen. Ozone is a deadly poison.
• Ozone is found in the stratosphere layer of the atmosphere.
• However, at the higher levels of the atmosphere, ozone performs an essential function. It shields the surface of the earth from ultraviolet (UV) radiation from the Sun.
• This radiation is highly damaging to organisms, for example, it is known to cause skin cancer in human beings or can split the DNA.

Its depletion:

• The amount of ozone in the atmosphere began to drop sharply in the 1980s.
• This decrease has been linked to synthetic chemicals like chlorofluorocarbons (CFCs) which are used as refrigerants and in fire extinguishers.
• The government bans those products which contain CFCs.

The correct option for the depletion of the ozone layer is Chlorofluorocarbons (CFC's).

Explanation:

Atmospheric Pollution: Pollution occurs due to the presence of undesirable solid or gaseous particles in the air.

• The following are the major gaseous and particulate pollutants

1. Gaseous air pollutants: These are oxides of sulphur, nitrogen and carbon, hydrogen sulphide, hydrocarbons, ozone and other oxidants.
2. Particulate pollutants: These are dust, mist, fumes, smoke, smog etc.

• When the quantity of acids in the raining water is more than the average, then such rain is called 'Acid rain'.
• We are aware that normally rainwater has a pH of 5.6.  When the pH of the rainwater drops below 5.6, it is called acid rain.
• Acid rain is a by-product of a variety of human activities that emit the oxides of sulphur and nitrogen in the atmosphere.
• As mentioned earlier, the burning of fossil fuels (which contain sulphur and nitrogenous matter) such as coal and oil in power stations and furnaces or petrol and diesel in motor engines produce sulphur dioxide and nitrogen oxides.

Hence the correct option is Air pollution.

Additional Information

SO2 and NO2 after oxidation and reaction with water vapour and sunlight are major contributors to acid rain because polluted air usually contains particulate matter that catalyses the oxidation.

2SO2 (g) + O2 (g) + 2H2O (l) → 2H2SO4 (aq)

4NO2 (g) + O2 (g) + 2H2O (l) → 4HNO3 (aq)

Concept:

Ecosystem: 

All organisms such as plants, animals, microorganisms and human beings as well as the physical surroundings interact with each other and maintain a balance in nature.

All the interacting organisms in an area together with the non-living constituents of the environment form an ecosystem.

• Biotic Components: It includes producers, consumers and decomposers.

All living things have a direct or indirect influence on other organisms in an environment. Ex- Plants, Animals, Microorganism etc.

• Abiotic components: All the in-organic components of the ecosystem, non-living physical and chemical composition of nature are abiotic components. Ex- stones, water, Humus (organic waste), air etc

Explanation:

There are two type of ecosystem -

• Natural Ecosystem - These are ecosystems that occur naturally and can survive without any intervention from human beings. Examples of natural ecosystems are forests, mountains, rivers, grasslands etc.
• Human-made or Artificial Ecosystem – When human beings modify the already existing ecosystem to meet their purpose or create an ecosystem of their own that mimics the natural condition, those are called artificial ecosystems. Examples of this type of ecosystem include aquariums, crop fields, gardens, dams, lakes, pond etc.
• This is because Pond and Lakes can be artificial as well. But forest can only thrive as a natural habitat.

Agricultural land - Artificial Ecosystem

Aquarium - Artificial Ecosystem

Grassland - Natural Ecosystem