User:Avinashraut/Nitrogen Fixation in Lonar Lake

NITROGEN FIXATION IN LONAR LAKE: A METEORITE IMPACT CRATER

The growth of all the organisms depends on the availability of mineral nutrients and none is more important than nitrogen. Nearly 79% of the earth’s atmosphere constitutes nitrogen gas but most organisms cannot use it in this form, as there is a triple bond between the two nitrogen atoms, making the molecule almost inert. Plants secure their nitrogen in a fixed form i.e. incorporated in compounds such as nitrate ions (NO3--), ammonia (NH3) and urea (NH2)2CO. Animals secure their nitrogen and all other compounds from plants, or animals that have fed on plants. Microorganisms have a central role in almost all aspects of this nitrogen availability and thus for life support on earth. Nitrogen is required in large amounts as an essential component of proteins, nucleic acids and other cellular constituents. Biological nitrogen fixation is a significant process of entry of nitrogen into an ecosystem and many nonsymbiotic microbial species play a major role in this. In an aquatic ecosystem the major regions where this activity occurs is the benthic and the littoral zones. is a closed basin lake formed in a meteorite impact crater formed some 50,000 years ago. It is situated near Lonar village in Buldhana district of Maharashtra (Lat. 190 58’, long. 760 34’). It is the only such lake formed in basaltic rock. Aerobic, nonsymbiotic nitrogen fixing bacteria have been reported for every conceivable ecosystem around the world including other similar aquatic environments elsewhere2. But there are no reports of such microorganisms from Lonar Lake and hence this provides an opportunity to study this aspect. Several non-symbiotic nitrogen fixing bacteria and nonsymbiotic nitrogen fixing actinomycetes have been discovered from this unique and exotic environment of Lonar Lake.