16. The most important strategy for the conservation of biodiversity together with traditional human life is the establishment of 

17. The scientific view is that the increase in global temperature should not exceed 2 °C above pre-industrial level. If the global temperature increases beyond 3 °C above the preindustrial level, what can be its possible impact/impacts on the world? 
1. Terrestrial biosphere tends toward a net carbon source.
2. Widespread coral mortality will occur.
3. All the global wetlands will permanently disappear.
4. Cultivation of cereals will not be possible anywhere in the world.

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18. Lichens, which are capable of initiating ecological succession even on a bare rock, are actually a symbiotic association of 

19. Which of the following are some important pollutants released by steel industry in India? 
1. Oxides of sulphur

2. Oxides of nitrogen
3. Carbon monoxide

4. Carbon dioxide

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20. Every year, a month long ecologically important campaign/festival is held during which certain communities/ tribes plant saplings of fruit-bearing trees. Which of the following are such communities/tribes?