Ants species richness and diversity in relation to different ecological habitat in selected localities of the semi-arid region of Karnataka, India.

We analysed the taxonomic position and species diversity of ants in four different habitats (agriculture, vegetative, dry land, and human habitats). A total of 11,038 ant workers belonging to 40 species, 25 genera of 10 tribes, and six subfamilies were recorded. The Simpson index of diversity (1-D) was 0.97, indicating greater diversity in both vegetative and human habitat. Similarly, the Shannon index was 3.40 and 3.50 for both vegetative and human habitats, respectively, indicating assemblage of similar ant species in both habitats. In contrast, for agricultural habitat, Simpson index of diversity (1-D) was 0.90, and for dry land habitat, the least diversity of 0.80 was reported. However, in pair-wise comparisons, no significant difference was observed between agriculture and dry land and vegetative and human habitats. The agriculture and arid land habitats tend to have fewer species compared with the vegetative and human habitats. Human-disturbed areas have an important role as reservoirs of biodiversity and should be included in landscape management practices to improve ant conservation in the tropics.

Ecology and abundance of zooplankton in Karanja reservoir.

The present work aims to study the Zooplankton seasonal distribution and diversity in Karanja reservoir, Bidar district for the period of two years from October 2001 to September 2003. We have recorded 36 species of which, 15 species belongs to rotifera, 11 species belongs to cladocera, nine species belongs to copepoda and ostracoda three species. Among zooplankton, particularly rotifera was the dominant group throughout the study period and highest count was recorded in the month of March 2003. Cluster analysis was also revealed by dendrogram and Shannon diversity index is also presented. Zooplankton community is also correlated with physicochemical parameters.

Concentration of heavy metals in Karanja reservoir, Bidar district, Karnataka, India.

In this study, some heavy metals concentrations (Zn, Pb, Fe, Mn, Cu, Ni) and other physico-chemical parameters were studied during October 2001 to September 2003 in Karanja reservoir, Bidar district. Water quality parameters were collected monthly basis whereas heavy metals were analyzed by Atomic Adsorption Spectrometer (AAS). Heavy metals have shown within the permissible limits, except Fe and Ni were recorded higher values in southwest monsoon, where as Mn has showed higher concentration in northeast monsoon in and summer. All other physico-chemical parameters are with in the permissible limit. Water is moderately hard and reservoir is productive.

Chemistry of groundwater in Gulbarga district, Karnataka, India.

Groundwater quality of Gulbarga District is extensively monitored for two years of study period from October 1999 to September 2001. Twenty-five different sampling stations were selected for the study purpose in the city and five selected villages in the district. Gulbarga districts lies in the northern plains of Karnataka State, covers an area of 16,244 km2 and lies between 16 degrees-11' and 17 degrees-19'N latitude and 76 degrees-54'E longitude The study revealed that the water sources in the area are heavily polluted. The major water quality parameters exceeding the permissible limits during all the seasons are total hardness, calcium hardness, magnesium hardness, alkalinity and MPN (Bacterial count) and other parameters have shown distinctive variation in different stations and season. Most of these parameters are correlated with one another. Statistical analysis of the data is presented.