PHYSICO -CHEMICAL STUDIES OF LONAR LAKE, MAHARASHTRA, INDIA

BIOINFOLET 13 ( 2 B ) : 406 - 408, 2016 PHYSICO -CHEMICAL STUDIES OF LONAR LAKE, MAHARASHTRA, INDIA Kshama S.Khobragade and Vijaykumar B. Pawar Department of Environmental Science, S.B.E.S. College of Science, Aurangabad ABSTRACT An attempt was made during present investigation to evaluate physicochemical qualities of water from Lonar Lake. For this purpose the water samples were analyzed for physico - chemical qualities, from 2012 to 2013 to find out seasonal variation. The results obtained revealed that, the water was alkaline (pH 10.5) characterized by high Alkalinity (5786 mg / liter), Sulphate (67 mg / liter), Magnesium (1043 mg / liter), Chloride (2816 mg / liter) and Dissolved Oxygen (0.03 mg/ liter). The alkalinity increased in monsoon and postmonsoon seasons while it decreased in pre-monsoon season. Like wise the chloride and salinity increased in pre monsoon season while decreased in monsoon and post-monsoon season. Keywords: Lonarlake, Physico-chemical properties, Microbiology Introduction: Lonar Lake, located in Buldhana district of Maharashtra state, India is a circular lake occupied by saline water (Fig.1). It is formed by hypervelocity meteoritic impact in basalt rock of the Deccan Traps near about 50 thousands years ago. Its diameter is about

Material and Methods: Water samples were collected from four sampling stations (Figure 1) in airtight and

1830 m. and depth is 135 m. The water in Lonar lake is stagnant since last thousands years. The water is salty, alkaline and the lake is rich in various biotic and a biotic assemblages. Attempts have been made during present investigation to study physico-chemical characters of water from this lake, collected during the years 2012 -2013.

opaque polythene containers. The water samples were analyzed seasonally from four sampling sites continuously for a period of one year i.e. from 2012 to 2013 following Standard

BIOINFOLET analytical methods (APHA, 1989; Trivedy and Goel, 1986, Kale and Bhusari, 2001). Result and Discussions: The results obtained on physicochemical characters of water samples collected from four sampling stations are given in Table 1. The temperature of water ranged from 23.6 to 24.4 which varied with respect to depth season and environment. The depth of water varied at different places. All physicochemical characteristics of Lake resulted into an extreme alkaline ecosystem with different microbial types prevailing in and around the Lake. Lonar Lake is characterized by hyper saline environment due to the presence of higher concentrations of various salts (Choudhary and Handa, 1978). The colour of Lake water was yellowish green to dark green resulting due to dense algal population. The pH of water sample was found to be alkaline which ranged between 7.2 to 11.2. The Maximum permissible limit of Total Dissolved Solid (TDS) is 1500 mg/liter for drinking water (BIS, 1991). During present investigation it ranged from 8900 to 12460 mg/liter which was very high and above the permissible limit, hence unsuitable for drinking. The chloride concentration in the lake varied from 55.5 to 2816 mg/liter which was above the permissible limit of 250 mg/liter as given by BIS (1991). This indicated polluted nature of lake water. The values of Ca and Mg were found to be very

407 high which may lead to hardness of water (Jain et. al., 1997) The uniqueness of the Lonar lake is the high pH of lake water. It has been found that the pH is lowering down which is a serious sign for this special aquatic ecosystem. The Lonar Lake is unique in the world for its alkalinity and salinity of the water but it was seen that chlorides and salinity of the Lake water is decreasing day by day, Hence this World heritage should be preserved for its alkalinity and salinity References APHA. (1989). Standard Methods for the Examination of Water and Wastewater (17th ed.). American Public Health Association. Washington D.C.: BIS. (1991). Indian standard specification for drinking water. Bureau of Indian Standards. New Delhi. Chaudhari, A. N., and Handa, B. K. (1978). Indian Journal Earth Science 5 : 111. Jain, C. K., Bhatia K., K. S., and Vijay, T. (1997). Indian Journal Environmental Health , 39 (3) : 182. Kale, V., & Bhusari, K. (2001). “Practical Microbiology -Principles and Techniques”. Himalaya Publishing House, Mumbai. Trivedy, R.K. and Goel, P. K. (1986). “Chemical and Biological Methods for Water Pollution Studies”. Environmental Publications, Karad

408 Table 1 : Physico-chemical parameters of Lonar Lake water samples