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• Sleeplessness and headache
• Noise level of 150 dB or more than these can cause permanent hearing impairment
• Increased heart beating and blood pressure
• Difficultly in breathing
• Strees and strain

Biochemical Oxygen Demand.

Answer is (b) N₂ & P

Colony collapse syndrome in Honey bees due to pesticides/herbicides can lead to destruction of hives and lower agricultural productivity.

Switch over to CNG in public transport system 

Enforcement of Euro II norms for vehicles. 

Compulsory periodic check-up of pollution. 

Use of unleaded petrol Low sulphur petrol and diesel 

Catalytic converters in vehicles Phasing out of old vehicles.

The new auto fuel policy introduced by the government of India is to reduce the sulphur,carbon monoxide and aromatics content in petrol and diesel fuels. The above mentioned things can be put in practice by different engine norms.

1. Bharat Stage II (equivalent to Euro norms) 

2. Euro III emission specifications

3. Euro-IV

1. Sample A is highly polluted.

2. BOD (Biochemical Oxygen demand).- refers to the amount of O₂ that is consumed when organic matter is oxidised by bacteria. If greater the BOD of water, the rate of pollution is high.

Ozone found in stratosphere. CFCs discharged from lower atmosphere move upward. In stratosphere UV rays act on these CFCs release chlorine atoms. Chlorine degrades ozone and release molecular oxygen (O₃O₂). In this reaction chlorine acts, as catalyst and loss ozone is irreversible.

Chemicals which are used in agriculture for growth of plants and pest control are called agrochemicals or agrichemicals.

1. Green house gases - CFC, N₂O, CH₄ , CO.

2. In the atmosphere green house gases causes re radiation of infrared radiation & results in the over heating of earth. This is called global warming. Global warming causes changes in the climate

Eg. EL Nino effect, Increased melting of polar ice caps rise in sea levels & submerging of coastal areas.

3. Suggest any three methods to control it:

• Cutting down the use of fossil fuel,
• Improving efficiency of energy usage,
• Reducing deforestation, planting trees

They are toxic to non-target organisms. They cause soil pollution Excess fertilizers cause eutrophication.

Un-Leaded Petrol- Reduces lead pollution in air. 

Low Sulphur Diesel- Reduces sulphur pollution in air. 

Four stroke engines to reduce emission of unburnt hydrocarbons. 

Tube-Ups to increase air-fuel ratio and help in better combustion. 

Catalytic Converters to reduce pollution. 

CNG to reduce pollution and conserve fossil fuels.

Cutting down the use of fossil fuel Improving the efficiency of energy usage

Reduce use of fossil fuel Efficient use of energy. 

Avoid deforestation 

Reduce human population 

Control greenhouse gases.

• Global warming is rise in mean temperature of lower atmosphere and earth’s surface.
• Causes – increase in quantity of radioactively active green house gases CO₂, CH₄, N₂O, CFCs. They allow heat waves to reach surface and prevents their escape. 
• They are produced by combustion of fossil fuels, biomass [CO₂]; burning of nitrogen rich fuels [N₂O]; paddy fields, fermentation in cattle and wet lands [CH₄]; refrigerators, aerosols, drying, cleaning [CFCs].
• Effects: Heating of earth surface [mean temperature is increased] Climatic changes e.g.: El Nino effect.
• Increased melting of polar ice caps and Himalayan snow caps. Increased sea levels and coastal areas will submerge.
• Measures – Decreased use of fossil fuels, improve efficiency of energy usage, Reduce deforestation, plant trees Control of man made sources of green house gases like vehicles, aerosol sprays.

Plants absorb and assimilate the pollutants like CO₂ and provide oxygen by the process of photosynthesis. This reduces the pollution.

Name the city in Delhi entire public road transport runs on CNG.

The soil particles carried by water from the source of supply.

The soil particles carried by water from the source of supply.

Nitrate, phosphate, metal ions and organic compound.

Its BOD increases and Dissolved oxygen reduces as microbes consume oxygen during their metabolism.

Sound that is unwanted and undesirable or can disrupt one’s quality of life is called as Noise. When there is lot of ‘noise’ in the environment, it is termed as Noise Pollution.

Certain measures help to remove pollutants, reduce their presence or prevent their entry into the atmosphere.

1. Trees are the best remedy for urban particulate and gaseous pollution. 

2. Forests act as carbon sinks and lungs of the planet. 

3. Catalytic converters in vehicles help to reduce polluting gases drastically 

4. Diesel exhaust filters in automobiles cuts particulates.

5. Electrostatic precipitators reduce release of industrial pollutants. 

6. Cost effective air pollution treatment systems like indoor plants and high performance bio filters can improve indoor air quality

Dobson Unit is the unit of measurement for total ozone. One DU is the number of molecules of ozone that would be required to create a layer of pure ozone 0.01 millimetre thick at a temperature of 0° C and a pressure of 1 atmosphere.

Ozone layer is a region of Earth’s stratosphere that absorbs most of the Sim’s ultra violet radiation. The ozone layer is also called as the ozone shield and it acts as a protective shield, cutting the ultra-violet radiation emitted by the sun.

1. The ozone layer of troposphere is called bad ozone.

2. The ozone layer of stratosphere is called good ozone.

Ozone hole in Antartica is due to special atmospheric and chemical conditions that existed there and nowhere else in globe.

1. Increasing the vegetation cover, grow more trees 

2. Reducing the use of fossil fuels and green house gases 

3. Developing alternate renewable sources of energy 

4. Minimising uses of nitrogeneous fertilizers, and aerosols.

Correct Answer is: (a) Petunia

Rainwater harvesting is the accumulation and storage of rain water for reuse in-site rather than allowing it to run off. Rainwater can be collected from rivers, roof tops and the water collected is directed to a deep pit. The water percolates and gets stored in the pit. RWH is a sustainable water management practice implemented not only in urban area but also in agricultural fields, which is an important economical cost effective method for the future. 

Environmental benefits of Rain Water Harvesting:

1. Promotes adequacy of underground water and water conservation. 

2. Mitigates the effect of drought. 

3. Reduces soil erosion as surface run-off is reduced. 

4. Reduces flood hazards. 

5. Improves groundwater quality and water table decreases salinity.

6. No land is wasted for storage purpose and no population displacement is involved. 

7. Storing water underground is an ecofriendly measure and a part of sustainable water storage strategy for local communities.

The increase in mean global temperature due to increased concentration of green house gases is called global warming.

(c) Petunia species

(d) Promoting the use of private rather than public transport.

Carbondioxide is the most abundant greenhouse gas. Increase in CO₂ level in the air decreases the uptake of nitrogen components leading to protein deficiency and chlorophyll formation.

The gases that capture heat are called Green House Gases. 

E.g: Carbon dioxide (CO₂)

Correct Answer is: (b) 20

CO₂ , CH₄ , N₂ O and CFC

Paddy field, fossil fuel production, bacteria in water bodies, cattle rearing, non-wetland soils and forest & wild fires.

(d) Botanical gardens

Correct Answer is: (C) O₂

Effects of deforestation: 

1. Burning of forest wood release stored carbon, a negative impact just opposite of carbon sequestration.

2. Trees and plants bind the soil particles. The removal of forest cover increases soil erosion and decreases soil fertility. Deforestation in dry areas leads to the formation of deserts.

3. The amount of runoff water increases soil erosion and also creates flash flooding, thus reducing moisture and humidity.

4. The alteration of local precipitation patterns leading to drought conditions in many regions. It triggers adverse climatic conditions and alters water cycle in ecosystem.

5. It decreases the bio-diversity significantly as their habitats are disturbed and disruption of natural cycles.

6. Loss of livelihood for forest dwellers and rural people. 

7. Increased global warming and account for one-third of total CO emission. 

8. Loss of life support resources, fuel, medicinal herbs and wild edible fruits.

Benefits of agroforestry:

1. It is an answer to the problem of soil and water conservation and also to stabilise the soil (salinity and water table) reduce landslide and water run-off problem. 

2. Nutrient cycling between species improves and organic matter is maintained.

3. Trees provide micro climate for crops and maintain CO₂ balanced, atmospheric temperature and relative humidity.

4. Suitable for dry land where rainfall is minimum and hence it is a good system for alternate land use pattern. 

5. Multipurpose tree varieties like Acacia are used for wood pulp, tanning, paper and firewood – industries. 

6. Agro-forestry is recommended for the following purposes. It can be used as Farm Forestry for the extension of forests, mixed forestry, shelter belts and linear strip plantation.

(d) Decreases O₂ content of water bodies

(d) Amount of agricultural land

(b) A is incorrect R is correct.

In-situ conservation: 

1. Conservation of species in their natural habitat. 

2. E.g: Biosphere reserves

Ex-situ conservation:

1. Conservation of species outside their natural habitat.

2. E.g: Zoological parks

(d) Both A and R are incorrect.

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(a) Dolphin 

(b) Bio magnification is the increase in the amount of non biodegradable substance in successive trophic level in a food chain.

Eg: DDT Eutrophication is the overgrowth of aquatic plants as a result of accumulation of nutrients in water body.

Peroxyacetyl nitrate (PAN) is a secondary pollutant present in photochemical smog. It is thermally unstable and decomposes into peroxyethanol radicals and nitrogen dioxide gas causing eye irritation.

El Nino effect refers to the odd climatic changes due to rise in temperature. It leads to increased melting of polar ice caps as well as other places like the Himalayan snow caps. This will result in a rise in sea level that can submerge many coastal areas. Thus, resulting in biodiversity loss.