List the important steps involved in nitrogen cycle in the biosphere.
The imporatnat steps involved in nitrogen cycle :
(i) Nitrogen fixation - and assimilation of free atmospheric nitrogen by Rhizobium or blue-green algae.
(ii) Nitrogen is converted to its oxides during lightning and in the prsence of high temperature and pressure. These oxides dissolve to give nitric and nitrous acid and fall on land along with rain.
(ii) Ammonification - conversion of ammonia to nitrites by Nitrosomonas (nitrifying bacteria).
(iii) Nitrification - conversion of nitrites to nitrates by Nitrobactor.
(iv) Denitrification - break down of nitrates to free nitrogen by Pseudomonas (denitrifying bacteria).
Is it necessary to replenish forests?
What measures one should take to maintain the fertility of the soil?
List four points which one should know regarding cycling of materials.
Why is replenishment of soil essential ? Describe two natural ways of soil replenishment.
