In the current study, the duckweed aquatic macrophyte Spirodela polyrrhiza was employed for assessing the toxicity of two wetlands in the Eloor industrial estate, Ernakulam district, Kerala, South India. The assessments were made according to OECD guidelines for testing (2006). The studies involve study of growth parameters, Growth Index, Biomass and changes in productivity. The water samples were collected from two different wetland sites at the same time. The spirodela plants were introduced into several dilutions of wetland water samples. The parameters were measured after 7 days of exposure. All samples except control affected all parameters. The results of this study emphasize the significance of duckweeds as standard and reliable testing material for biological parameters in polluted aquatic ecosystem
Description:
IOSR Journal Of Environmental Science, Toxicology And Food Technology (IOSR-JESTFT),Volume 1, Issue 6 (Nov. - Dec. 2012), PP 44-49
Harindranathan Nair, M V; Smitha, S V; Amarnath, A; Chitra, S V(International Science Congress Association, February , 2013)
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Abstract:
Urbanization refers to the process in which an increasing proportion of a population lives in cities and suburbs. Urbanization fuels the alteration of the Land use/Land cover pattern of the region including increase in built-up area, leading to imperviousness of the ground surface. With increasing urbanization and population pressures; the impervious areas in the cities are increasing fast. An impervious surface refers to an anthropogenic ally modified surface that prevents water from infiltrating into the soil. Surface imperviousness mapping is important for the studies related to water cycling, water quality, soil erosion, flood water drainage, non-point source pollution, urban heat island effect and urban hydrology. The present study estimates the Total Impervious Area (TIA) of the city of Kochi using high resolution satellite image (LISS IV, 5m. resolution). Additionally the study maps the Effective Impervious Area (EIA) by coupling the capabilities of GIS and Remote Sensing. Land use/Land cover map of the study area was prepared from the LISS IV image acquired for the year 2012. The classes were merged to prepare a map showing pervious and impervious area. Supervised Maximum Likelihood Classification (Supervised MLC),which is a simple but accurate method for image classification, is used in calculating TIA and an overall classification accuracy of 86.33% was obtained. Water bodies are 100% pervious, whereas urban built up area are 100% impervious. Further based on percentage of imperviousness, the Total Impervious Area is categorized into various classes
Description:
Research Journal of Recent Sciences,
Vol. 2(ISC-2012), 241-244 (2013)
Ammini, Joseph; Valsamma, Joseph(Kluwer Academic Publishers, January 17, 2002)
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Abstract:
The microalgal community as primary producers has to play a significant role in the biotic
and abitoic interactions of any aquatic ecosystem. Whenever a community is exposed to a pollutant,
responses can occur because individuals acclimate to pollutant caused changes and selection can
occur favouring resistant genotypes within a population and selection among species can result in
changes in community structure. The microalgal community of industrial effluent treatment systems
are continuously exposed to pollutants and there is little data available on the structure and seasonal
variation of microalgal community of industrial effluent holding ponds, especially of a complex
effluent like that of refinery. The aim of the present study was to investigate the annual variation in
the ecology, biomass, productivity and community structure of the algal community of a refinery
effluent holding pond. The results of the study showed the pond to be a eutrophic system with a
resistant microalgal community with distinct seasonal variation in species composition
Description:
Environmental Monitoring and Assessment 80: 175–185, 2002
Heterotrophic bacterial flora of Pmonadon from an apparently healthy hatchery system as well as a pool with heavy mortality were isolated and studied. In the
healthy systems comparatively higher generic diversity with Pseudomonas, Acinetobacter, Bacillus, Micrococcus, members of the family Enterobacteriaceae
and coryneform group in the diminishing order of dominance was recorded. Meanwhile from the moribund larvae and rearing water Aeromonas and Pseudomonas
could be isolated in almost equal proportions. Strikingly, Aeromonas could not be isolated from the apparently healthy larval rearing system and its exclusive
occurrence in the sick culture system in comparatively higher percentage suggested its possible role in the mortality. They were found to be highly halophilic
exhibiting growth at 10% NaCl. On testing their sensitivity to twenty antibiotics, four of them (Streptomycin, Gentamycin, Methamine mandelate and
Cloramphenicol) were found to be effective on all the isolates of Aeromonas and Pseudomonas suggesting their possible application in the hatchery system in
times of emergency. While doing so, Streptomycin would do comparatively better than the others as the minimum inhibitory dose required was comparatively
lower (200ppm) within a period of 24 hours
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The Fourth Indian Fisheries Forum Proceedings
24-28. Ncvemher, 1996. Kochi . p. 327-331).