Pratyashi Phukan and Ranjan Saikia
1Department of Geography, Gauhati University, Ghy-14 Assam, INDIA
²Department of Geography, Cotton College, Guwahati-1 Assam, INDIA
Available online at: www.isca.in, www.isca.me
Received 30th November 2013, revised 26th March 2014, accepted 19th April 2014