If an agricultural field is liberally irrigated for a prolonged period of time, it is likely to face the problem of:

1.	Metal Toxicity	2.	Alkalinity
3.	Acidity	4.	Salinity

Which of the following statements about ozone is correct?

1. Tropospheric ozone protects us from UV radiation

2. Stratospheric ozone is 'bad'

3. Tropospheric ozone is 'good'

4. Stratospheric ozone protects us from UV radiation

'Ozone depletion' means thinning of ozone layer during spring season and 

1. This will allow UV-A to enter stratosphere which will cause snow blindness 

2. This is caused by ${\mathrm{N}}_2\mathrm{O}$ as major pollutant

3. Ozone is released during this as ${\mathrm{O}}_2$ or ClO

4. First large hole was discovered over north pole

Flamingoes, corymorants or cranes will be harmed the most if the aquatic system is polluted by

1. $N{O}_x$

2. Fertilizers

3. DDT

4. Domestic sewage

Pick the correct set of gases labelled A, B, C and D in the given figure showing their respective contribution to global warming

1. $A-CFCs,<mspace\; width="1em"></mspace>B-C{H}_4,<mspace\; width="1em"></mspace>C-C{O}_2,<mspace\; width="1em"></mspace>D-N_{2}O$

2. $A-C{O}_2,<mspace\; width="1em"></mspace>B-C{H}_4,<mspace\; width="1em"></mspace>C-CFCs,<mspace\; width="1em"></mspace>D-N_{2}O$

3. $A-N_{2}O,<mspace\; width="1em"></mspace>B-C{H}_4,<mspace\; width="1em"></mspace>C-C{O}_2,<mspace\; width="1em"></mspace>D-CFCs$

4. $A-C{O}_2,<mspace\; width="1em"></mspace>B-CFCs,<mspace\; width="1em"></mspace>C-C{H}_4,<mspace\; width="1em"></mspace>D-N_{2}O$

During the past century, the temperature of Earth has increased by _____, most of its during the last three decades
1. 6°C
2. 0.6°C
3. 0.8°C
4. 7°C

Which is not an effect of global warming

1. more extreme weather condition

2. melting of polar ice caps

3. Rise of sea level

4. Good fungal growth in soil

Biomagnification of DDT in aquatic food chain leads to high concentration of DDT in fish eating birds. It results in

1. (1) and (2) only
2. (2) and (3) only
3. (1) and (3) only
4.  All (1), (2) and (3)

National Forest Policy __A__ of India has recommended __B__ forest cover for the plains and __C__ for the hills. Fill the blanks with suitable A, B and C
      A       B        C
1. 1988   33%   67%
2. 1988   30%   19.4%
3. 1989   30%    65%
4. 1987   19.4%  30%

Cleaning of wastewater in Arcata Marsh involves

1.  Only conventional method of sewage treatment

2.  Removal of dissolved heavy metals through a biological process

3.  Filteration, chlorination like chemical processes

4.  Utilisation of microorganisms only for pollution control