Cauvery River is the major river system of south India was studied for 19 prime physicochemical and 2 bacteriological parameters at six locations of the Kollegal stretch, for a period of Two years (2006)(2007)(2008) at monthly intervals. Over the years of time, river has been subjected to human interference regularly and water quality was to be getting deteriorated profoundly. Major anthropogenic activities practiced in and around the stretch: agriculture, abstraction of water for irrigation and drinking, washing cloths and utensils, discharging of sewage waste, sand dredging, boating, fishing, open defecation and religious ritual activities along the stretch were generating serious threat to the biota of the river by altering the physicochemical and biological concentration of the river system. The seasonal and yearly trends were discussed to comprehend anthropogenic interferences on the river stretch. Correlation analysis was also been tried in between physico-chemical parameters. The pH, Conductance, Alkalinity and Hardness levels indicate the moderate quality of water. The values of DO, BOD and COD levels indicate the absence of major organic pollution sources. Seasonal and yearly averages of plant nutrients like phosphate, nitrates, potassium and also sulphates at drain out falls and mixing zones, were not showing any significant variation in their concentration indicate no sign of problems like eutrophication, which is generally raise due to agricultural and sewage wastes. The other possibility is that since there are no major industries in the project area, the major source of organic pollutants is only the domestic source. Population density spread over sparsely located villages like Dasanapura and Harle certainly contributes towards total and fecal coliforms as excreta of the villagers due to lack of toilets in their houses. Thus present study concludes that river water was not polluted; all results are within permissible limit when compared with Bureau of Indian Standards (BIS) and National River water quality standards. INTRODUCTIONRivers are vital and vulnerable freshwater systems that are critical for the sustenance of all life. However, the declining quality of the water in these systems threatens their sustainability and is therefore a cause for concern. Rivers are waterways of strategic importance across the world, providing main water resources for domestic, industrial, and agricultural purposes (Faith, 2006).

The purpose of this research work was to appraise extent of heavy metals in sediment and the degree to which its quality tainted seasonally and spatially in river Cauvery. In this study, heavy metals such as Fe, Zn, Ni, Mn, Pb, Cu, Co, Cd and Cr were analysed in sediments. Results were compared with sediment quality guidelines from various derived criteria. Twenty-five sampling points were selected based on geographical proximity of agricultural fields and industrial discharges; river-tributary confluence points; settlements located along the river bank; ritual and recreational activities. Sampling was done for the period of 3 years (2007 to 2009). Digestion of the samples was done by microwave-assisted digestion technique. Analysis was carried out using flame furnace atomic absorption spectrophotometer, and results are expressed in micrograms per gram. The mean concentration of Fe (11144 μg/g) followed by Mn (1763.3 μg/g), Zn (93.1 μg/g), Cr (389 μg/g), Ni (27.7 μg/g), Cu (11.2 μg/g), Pb (4.3 μg/g), Co (1.9 μg/g) and Cd (1.3 μg/g) remained within the levels of sediment quality guidelines. Multivariate statistical techniques such as principal component analysis and cluster analysis (CA) were employed to better comprehend the controlling factors of sediment quality and spatial homogeneity among the stations. The sediment geo-accumulation index (I(geo)) showed maximum value of Cd (2.69) and least value of Mn (-1.44). The geo-accumulation class (I(geo) class) was in the sequence as follows: Cd>Zn>Pb>Cr>Cu>Co>Ni>Fe>Mn. Negative total geo-accumulation indices (I(tot)) revealed that mean concentration of heavy metals in the river bed sediment are lower than their respective shale values. The statistical analysis of inter-metallic relationship revealed the high degree of correlation among the metals indicated their identical behaviour during transport. This study concludes that insignificant geo-accumulation with metals except Cd (moderate contamination), Pb and Zn (slight contamination) principally in downstream stretch may perhaps deteriorate the sediment quality due to intensification anthropogenic influences. It also proves that extent of existing metal concentrations in sediments of river Cauvery in Karnataka not exceeded the toxic limit, and there is no peril to the aquatic life.

The Bandipur National Park situated in the Western Ghats of Karnataka State, is one of the biodiversity hotspots of the world. During recent years, this park has witnessed repeated fires, affecting considerable areas under vegetation. The temporal satellite data from 1997 to 2006 have been analyzed to map the burnt areas using Remote Sensing (RS) and Geographic Information System 123 RESEARCH ARTICLE (GIS) techniques. The vegetation cover is moist deciduous, dry deciduous, scrub forests and teak plantation. Information on extent of the burnt areas and the type of vegetation affected were derived forest range-wise. The fire prone regions have been identified by integrating vegetation type/density, road and settlement network and past history of forest fire occurrence, by assigning subjective weightage according to their fire-inducing capability or their sensitivity to fire. Comparison between each temporal dataset in terms of the extent of burnt area was also carried out to interpret fire incidence pattern. Three categories of fire risk regions such as Low, Moderate and High fire intensity zones were identified and it was found that almost 40% of the study area falls under low risk zone. An evaluation of the existing fire management systems and the implication of fire prevention programmes has been discussed, besides an assessment of causal factors for fire incidence in the park. 3 8

Anekal Taluk lies in the southern part of the of Bangalore urban district, known for Bannerghatta wildlife sanctuary, Jigani industrial estate, silk industry, and the electronics city, the pride of India and hub of Bangalore's information technology. In the present study, evaluation of geochemistry of 28 representative bore wells samples from Anekal Taluk was undertaken. It was found that most of the samples (92.9%) belong to Ca(2+ )-Mg(2+ )-Cl( - ) -SO²⁻₄water type with Ca-Mg-Cl and Ca-Cl hydrochemical facies. The groundwater sources were further categorized as normal chloride (32.14%) and normal sulfate (100%) water types based on Cl and SO(4) concentrations. Majority of the samples (64.3%) belong to C3-S1 water class, indicating water with high salinity and low sodium. Positive index of base exchange indicates the chloro-alkaline equilibrium in the study area. Groundwater potential zonation map for Anekal Taluk was generated using multiparametric and weighted overlay method using the spatial analyst tool in ArcGIS v9.2. Accordingly, five distinct classes corresponding to good(high), moderate (medium), moderate to poor (low), poor (very low), and poor to nil (very low) groundwater potential zones were identified in the region. Of this, 85.27% of the study area belongs to good/high to moderate/medium groundwater potential and only 14.73% belonging to moderate/poor to nil groundwater potential zones.

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