Assessment of the toxicity of waste water from a textile industry to Cyprinus carpio.

Static, short-term, acute toxicity tests were performed over a period of 96 hrs using different concentrations of influent and effluent of textile industry waste water with the objective of evaluating their acute toxicity on fresh water fish, Cyprinus carpio (common carp). The LC50 24, 48, 72 and 96 hr of influent and effluent were 25.9, 21.10, 15.66, 11.11% (v/v) and 63.18, 54.89, 48.62, 36.04% (v/v), respectively. The acute toxic unit TUa values for 24, 48, 72, 96 hr for influent and effluent are 3.85, 4.73, 6.38, 8.99 and 1.58, 1.82, 2.05, 2.77, respectively. Correspondingly, the TF was found to be 1, 1.22, 1.65 and 2.33 for influent, and for effluent 1, 1.15, 1.29 and 1.75. Total efficiency of the treatment was 69.16% and the safe concentration of effluent is set to be 3.60%. These data are highly useful in establishing limits of acceptability by the aquatic animals. The need to introduce toxicity evaluation assay for confirming the quality of effluent from the point view of effective environmental safe limits and to ensure integrity of aquatic environment, is stressed.

Application of remote sensing and geographical information system in mapping forest fire risk zone at Bhadra wildlife sanctuary, India.

Fire is the most spectacular natural disturbance that affects the forest ecosystem composition and diversity. Fire has a devastating effect on the landscape and its impact is felt at every level of the ecosystem and it is possible to map forest fire risk zone and thereby minimize the frequency of fire. There is a need for supranational approaches that analyze wide scenarios of factors involved and global fire effects. Fires can be monitored and analyzed over large areas in a timely and cost effective manner by using satellite imagery. Also Geographical Information System (GIS) can be used effectively to demarcate the fire risk zone map. Bhadra wildlife Sanctuary located in Karnataka, India was selected for this study. Vegetation, slope, distance from roads, settlements parameters were derived for a study area using topographic maps and field information. The Remote Sensing (RS) and Geographical Information System (GIS)-based forest fire risk model of the study area appeared to be highly compatible with the actual fire-affected sites. The temporal satellite data from 1989 to 2006 have been analyzed to map the burnt areas. These classes were weighted according to their influence on forest fire. Four categories of fire risk regions such as Low, Moderate, High and Very high fire intensity zones were identified. It is predicted that around 10.31% of the area falls under moderate risk zone.

Temporal-scale spectral variability analysis of water quality parameters to realize seasonal behaviour of a tropical river system - River cauvery, India.

This paper describes the Time series analysis of river water quality with emphasis on variation in parameters as evidenced by statistical approach and mathematical models. The extensive study enabled to differentiate and realize the behaviour of river and catchment’s changes induced by human activities. The Time series analysis evaluation indicated trivial variation and movement in the water quality as reflected by the changes in the catchment characteristics. Although the observed trends showed an insignificant human contribution to basin hydrology and river water chemistry, noticeable human activities and unsustainable practices steadily contributed to change in water quality from the existing long term spectral signatures to short term spectral signatures. It is inferred that short term spectral signature exhibited on temporal scale by a monitoring program of this kind reflects an insalubrious river system and long term gradual changes in spectrum is an indication of healthy system. Monitoring and analyses of these decisive changes in water quality parameters over a period could be a powerful tool for assessing general river water quality and management plan.

Prevalence of Staphylococcus aureus and Pseudomonas aeruginosa in indoor air flora of a district hospital, Mandya, Karnataka.

Two year (1998 and 1999) extensive survey was carried out in Mandya district hospital, Karnataka for a period of three years to monitor the prevalence of Staphylococcus aureus, Pseudomonas aeruginosa (S. aureus and Ps. aeruginosa) from the indoor air samples of operation theater labor room, children's ward, male and female general wards postoperative wards etc. A rotary air sampler loaded with manital salt and Pseudomonas selection agar media strips were used to collect the samples from various sites. The survivallence results revealed the prevalence of S. aureus and Ps. aeruginosa in almost all sampling sites, irrespective of season indicating their long-term survival and consequent threat to hospitalized patients as well the working employees.

Groundwater quality--assessment on Anekal Taluk, Bangalore Urban district, India.

Water as a resource, basic amenity and universal solvent is shared by population. The physicochemical and biological quality study of Anekal Taluk has been taken up to evaluate its suitability for potable purposes. 1026 water samples were collected from bore well, hand pumps of 272 villages covering in Anekal Taluk. The quality of groundwater has been made through the analysis of pH, colour, electrical conductivity, turbidity, total dissolved solids, alkalinity, chlorides, total hardness, calcium, fluoride, nitrate, sulphate, iron and E. coli. The quality of groundwater assessed in the study area is discussed in detail.

Tree species diversity and composition in logged and unlogged rainforest of Kudremukh National Park, South India.

Species composition and diversity in logged and unlogged forests were assesed to understand the regeneration of the residual stand twenty years after logging in Kudremukh National Park, South India. Relative density, frequency and basal area were measured by Point Centered Quarter method to calculate the diversity and stand quality. The logged forest harbored lower stem density of mature trees (508 ha(-1)) than unlogged ones (630 ha(-1)). Indeed, logging operations increased the species diversity in the regenerative phase (seedling phase) due to the creation of larger canopy gaps. The extra radiation reaching the ground, facilitated the colonization of early and late secondary species. Ramakrishanan Index of Stand Quality (RISQ) values in logged forest was higher in comparison with unlogged forest, indicating the dominance of early and late secondary species, especially at sapling phase. The light demanding secondary forest species contribute higher percentage to the overall tree population in logged forest. It is observed from the study that a sufficient period of felling cycle should be practiced to reinstate the same set of species prevailed before logging.

Impact of urbanization on Bellandur Lake, Bangalore--a case study.

Lake and river water is the prime source for drinking, irrigation and other domestic purposes. Bellandur Lake is one of the major Lakes of Bangalore city. The addition of effluents from urbanized Bangalore city has changed the characteristics of the Lake from being a natural ecologically healthy Lake to an artificial reservoir of domestic sewage and industrial effluents. The DO of the Bellandur Lake water ranged from 3.8-6.3 mg/l. The Bellandur lake water BOD ranged from 89-99 mg/l due to absorption of pollutants by aquatic flora in lake system. If the present state of affairs continues for long, the Bellandur Lake may soon become an ecologically inactive Lake.