Some industrial effluents in Durgapur and their impact on the Damodar river

The industrial waste effluents from two industries of Durgapur have been traced along the course of Tamla Nalah at selected sites up to its confluence with the Damodar river and downstream. There are evidences of contamination of the river with toxic pollutants—ammonia, phenol, cyanide, sulphide, and trace mercury from Tamla Nalah. The upstream river water (Durgapur barrage), which is believed to be fairly pure, is actually not much better than the downstream river water. Monitoring data for about a year are presented and discussed.     

Sewage fluxes and seasonal dynamics of physicochemical characteristics of the Bhagirathi-Hooghly River from the lower stretch of River Ganges,India

ABSTRACT

To understand the temporal variations of the physicochemical characteristics of the Bhagirathi-Hooghly River (BHR), three locations representing three districts of West Bengal were selected. The material fluxes from 34 drains during pre-monsoon season was quantified. The analysis of variance (ANOVA) revealed that no significant spatial variations were observed for the physicochemical parameters, whereas seasonal variations were significant. The mean discharge was found to be highest (247.2?×?10³?m³?d^?1) in the midstream drains. Highest mean concentrations of dissolved oxygen (DO) (7.35?mg?L^?1) and nitrate (0.81?mg?L ^?1) were observed during the post-monsoon season followed by the monsoon and pre-monsoon. According to the BIS, WHO and the European standard of water quality (pH, 6.5–8.5; Nitrate, 0–2.5?mg?L^?1;DO, ≥5?mg?L^?1), the results of the respective parameters revealed the BHR system is maintained at high to good water quality, meaning that the BHR system is slightly altered from its pristine environment. The mean concentrations of biological and chemical oxygen demands were found to be high during the monsoon season, revealing that a large quantity of refractory organic matter is transported to the eastern Bay of Bengal from the Ganges.     

Long-range potential source contributions of episodic aerosol events to PM10 profile of a megacity

This paper evaluates possible long-range source contributions to the PM₁₀ profile of Istanbul, Turkey. A novel method for classifying PM₁₀ episodic events resulting from long-range transport, as opposed to local ones, was implemented. Hourly PM₁₀ mass concentrations from ten stations distributed throughout Istanbul during the year 2008 were used for this purpose. Hourly backward trajectories for the arrival of air masses to the center of Istanbul for the year 2008 were calculated using the HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) model. Significant episodes from these backward trajectories were selected and employed in Potential Source Contribution Function (PSCF) analysis to estimate the possible contribution of long-range PM₁₀ transport (LRPMT) to observed PM₁₀ concentrations. The PSCF results showed significant seasonal variations. Based on the results obtained, PM₁₀ concentrations observed in Istanbul during summer and autumn are not heavily affected by LRPMT. Mediterranean countries, especially those of the central part of northern Africa (northern Algeria and Libya) are the most significant potential PM₁₀ contributors to Istanbul's atmosphere during springtime. During winter, Balkan countries, including the Aegean part of Turkey, Greece, Bulgaria, Serbia, and Croatia, as well as northern Italy, eastern France, southern Germany, Austria and the eastern part of Russia, were the most important LRPMT source regions for high PSCF values.     

Continuous Safety Sampling Methodology

This research introduces a proactive methodology for accident prevention, called Continuous Safety Sampling Methodology, by utilizing the principles of work sampling and control charting. Sampling is performed to observe the occurrence of conditions that may become hazardous in a given system. These conditions, known as dendritics, may become hazards and could result in an accident or occupational disease. Continuous Safety Sampling Methodology performs a random sampling for the occurrence of these dendritics. The collected data are then used to generate a control chart. Based on the pattern of the control chart, a system “under control” is not disturbed whereas a system “out of control” is investigated for potential conditions becoming hazardous. Appropriate steps are then taken to eliminate or control these conditions to maintain a desired safe system.     

Isolation and screening of sulfur-oxidizing bacteria from coast of Bhavnagar,India, and formulation of consortium for bioremediation

Environmental Science and Pollution Research - Reduced sulfur compounds are a nuisance in coastal industries causing heavy economical as well as ecological loss. One such compound, hydrogen...     

Assessment of noise level in Burdwan town, West Bengal

Cities and towns of the world are now facing enormous rise of noise pollution problem due to very high population rise, transport congestion and associated commercial and industrial activities. Burdwan, a district headquarter (100 km away from Kolkata) is one such town where noise pollution is very frequent. In order to assess noise level, noise data were collected from various places of the town by sound level meter with a duration of 30 minutes/location during specified time like 6.00 am, 10.00 am, 1.00 pm, 4.00 pm and 6.00 pm. Most of the monitoring places either belongs to silence category or commercial category areas. From the tabulated data, it was found that sound level lies within the range of 64-85 dB or above in different time at different places. The locations that belong to the silence zone have the noise level up to 90 dB. Statistically noise level in all these zones differ significantly at their peak hours. Noise pollution adversely affects our environment as well as human beings. Sound causes both pathological and psychological disorders in human beings. Implementation of rules and regulations under section 20, 21J, 41, 68(I), 70, 90, 111A of Environment Protection Act, 1986 and of course various technological methods and public awareness are very essential to check noise pollution in Burdwan town.     

Gyrineum natator: a potential indicator of imposex along the Indian coast

Imposex related studies have used neogastropods as sentinel organism. In this effort, we elucidate the potential of a mesogastropod, Gyrineum natator, for imposex monitoring on the central west coast of India. Observations were made with specimens collected from Mumbai (three stations), Ratnagiri (two stations), Goa (one station) and Mangalore (one station). The analyzed populations at all four sites were affected by imposex. The six different stages of imposex in this organism are illustrated through schematic and scanning electron micrographs. In view of the anticipated ban on TBT based antifouling paints this baseline information can serve as an indicator for environmental monitoring in this region.     

Thraustochytrid protists as a component of marine microbial films

Although ubiquitous in the marine environment, the presence and importance of thraustochytrid fungoid protists in primary film formation of freshly immersed surfaces in the sea have not been investigated. We isolated thraustochytrids from surfaces of glass, aluminium, mild steel and fibre glass panels immersed in sea water for 1 to 4 d, but not from those of copper and cupro-nickel. Microscopic examination of the primary film on glass surfaces revealed the presence of thraustochytrids. Thraustochytrids grew to varying population densities on surfaces of glass, aluminium and fibre glass in the laboratory. Scanning electron microscopy of the growth of Ulkenia profunda Gaertner, isolated from the primary film, on surfaces of glass and aluminium suggested that cells of the thraustochytrid attached directly to the surfaces, without producing copious extracellular polysaccharides. The presence of ectoplasmic net elements was not a prerequisite for attachment of cells to surfaces. Cell surface hydrophobicity of the thraustochytrid, as estimated by the MATH assay, might play an important role in adhesion. The presence of thraustochytrid cells on a polystyrene surface markedly induced settlement of barnacle larvae (Balanus amphitrite), as compared to barnacle extract and a control. Received: 26 July 1999 / Accepted: 21 January 2000     

Dinoflagellate community structure from the stratified environment of the Bay of Bengal, with special emphasis on harmful algal bloom species

Harmful algal blooms (HABs) have been documented along the coasts of India and the ill effects felt by society at large. Most of these reports are from the Arabian Sea, west coast of India, whereas its counterpart, the Bay of Bengal (BOB), has remained unexplored in this context. The unique characteristic features of the BOB, such as large amount of riverine fresh water discharges, monsoonal clouds, rainfall, and weak surface winds make the area strongly stratified. In this study, 19 potentially harmful species which accounted for approximately 14% of the total identified species (134) of dinoflagellates were encountered in surface waters of the BOB during November 2003 to September 2006. The variations in species abundance could be attributed to the seasonal variations in the stratification observed in the BOB. The presence of frequently occurring HAB species in low abundance (≤ 40 cell L(?-1)) in stratified waters of the BOB may not be a growth issue. However, they may play a significant role in the development of pelagic seed banks, which can serve as inocula for blooms if coupled with local physical processes like eddies and cyclones. The predominance of Ceratium furca and Noctiluca scintillans, frequently occurring HAB species during cyclone-prone seasons, point out their candidature for HABs.     

Variations in phytoplankton community in a monsoon-influenced tropical estuary

In a monsoon-affected tropical estuary, oscillations in freshwater discharge during monsoon shifted the phytoplankton blooms from those adapted to low salinities to high salinities and vice versa. Salinity stratification during monsoon (onset and restart after an intermittent break) favored diatom (Skeletonema) bloom in low-saline surface waters. In high-saline, nutrient-rich bottom waters, Fragilariopsis (diatom) bloom was observed during onset of monsoon and persisted till the end of monsoon. The break period in monsoon altered the phytoplankton community leading to mixed species bloom of large-sized diatoms and harmful dinoflagellates (Gymnodinium catenatum and Cochlodinium polykrikoides) under high-saline, nutrient-poor, non-stratified, and transparent water column. Such variations in community should be considered for better understanding the biogeochemistry of monsoon-influenced tropical estuaries. The dominance of Skeletonema is determined positively by the extent of low-saline stratified condition whereas most of the observed taxa were favored by high-saline, nutrient-poor, and transparent waters.