Studies on abundance of zooplanktons in lakes of Mysore, India.

This is the first comprehensive ecological study on the abundance of zooplankton in Kalale, Alanahalli and Dalvoy lakes of Mysore. The abundance of zooplankton as well as their relation with physico-chemical parameters was analyzed, every month in these lakes from June 2008-May 2010. The mean abundance of Rotifer (281 Org (l-1)), Cladocerans (27 Org l(-1)) and total abundance of zooplankton (343 Org l(-1)) were more and significantly different in Dalvoy lake; whereas, in Kalale lake the mean abundance of Rotifer (19 Org l(-1)), Cladocerans (3 Org l(-1)) and total abundance of zooplankton (79 Org l(-1)) and in Alanahalli lake the mean abundance of Rotifer (84 Org l(-1)), Cladocerans (9 Org l(-1)) and total abundance of zooplankton (149 Org l(-1)) were significantly less.

Monthly changes in the abundance and biomass of zooplankton and water quality parameters in Kukkarahalli Lake of Mysore, India.

Zooplankton abundance and distribution are of ecological importance, as they are very sensitive to change, therefore zooplankton make ideal indicators of aquatic ecosystem. This study carried out on the abundance of rotifer, cladoceran, cyclopoid-copepod and ostracod zooplankton groups and biomass of total zooplankton were studied every month for one year. It is interesting and noteworthy to note that Calanoid and Harpacticoid zooplankton groups and free carbon dioxide were completely absent in all the four sampling sites throughout the study year.

Temporal variation in the specific growth rate of bacterioplankton in the River Cauvery and its four down stream tributaries in Karnataka State, India.

The temporal variation in the Specific Growth Rate (SGR) of natural population of heterotrophic bacterioplankton of the river Cauvery and its four down stream tributaries in Karnataka State was monitored over a period of two years from February 2000 to January 2002. The SGR was calculated by taking into account only the abundance of bacterioplankton at the beginning (0 h) and at the end (48 h) incubation period, at room or river temperature. The mean SGR was less and significantly different in the surface waters of river Kapila, Shimsha, Suvarnavathy and Arkavathy.

Heterotrophic free-living and particle-bound bacterial cell size in the river Cauvery and its downstream tributaries.

This is the first comprehensive study on planktonic heterotrophic bacterial cell size in the river Cauvery and its important tributaries in Karnataka State, India. The initial hypothesis that the mean cell size of planktonic heterotrophic bacteria in the four tributaries are markedly different from each other and also from that in the main river Cauvery was rejected, because all five watercourses showed similar planktonic heterotrophic bacterial cell size. Examination of the correlation between mean heterotrophic bacterial cell size and environmental variables showed four correlations in the river Arkavathy and two in the river Shimsha.