OCCURRENCE OF MACRO-ZOO BENTHOS IN RELATION TO PHYSICO-CHEMICAL CHARACTERISTICS IN NAGARAM TANK OF WARANGAL, ANDHRA PRADESH

Abstract

Physico-chemical characteristics and macro-zoo benthos in the Nagaram tank during the year June 2007 – May 2009 have been studied. Water temperature (18 to 35ºC) of the tank was closely followed the atmospheric temperature (18 to 35ºC).The pH fluctuated between 7.1 and 9. Dissolved oxygen was within the moderate range of 0.25 to 6.90 mg/L. Alkalinity of the tank was also observed within the productive range (119 to 158 mg/L). The high value of alkalinity in the station - II might be due to presence of salts generated through the death and decay of the macrophytes and other aquatic organisms. The conductivity ranged between (119.50 to 600.20 mhos).The macro zoo benthic fauna of this tank belonged to gastropoda represented by 3 species belonging to Indoplanarbis, Bellanya bengalensis, (Lamarck), Thiara tubereulata (Muller); two species of bivalves belonging to Lamellidens corrianus (Lea), Parreysia, rugossa (Gmelin). Gastropods contributed 54% of the total zoo macro benthic population. The bivalves were available in lesser abundance compared to the Gastropods (46%).