Green method of stemming the tide of invasive marine and freshwater organisms by natural filtration of shipping ballast water

Environmental Science and Pollution Research - Marine and freshwater pollution caused by transport of invasive species in shipping ballast water is a major global problem and will increase in...     

Effect of gamma-irradiated sludge on the growth and yield of rice (Oryza sativa L. var. GR-3)

The effects of gamma-irradiated sludge on the growth and yield of rice (Oryza sativa L. var. GR-3) in pot cultures have been studied. Compared to plants grown only in soil, shoot length, root length, fresh weight, dry weight, total proteins, total soluble sugars, starch and chlorophyll content of plants grown in soil supplemented with unirradiated or gamma-irradiated sludge were found to be significantly increased. Irradiation of sludge significantly stimulated the linear growth of shoot and root systems as well as fresh and dry weights of plants, compared to those grown in soil containing unirradiated sludge. There was also an improvement in the grain yield (weight of seed) when plants were grown in soil supplemented with irradiated sludge. The results obtained suggest that the gamma-irradiated sewage sludge can be beneficially recycled for agricultural uses.     

Incineration at Bayou Bonfouca Remediation Project

The Bayou Bonfouca hazardous waste site is located in Slidell, Louisiana, approximately 96 kilometers (60 miles) northeast of New Orleans. This site is ranked number 1,006 on the National Priorities List of Superfund sites. The U.S. Environmental Protection Agency (EPA) conducted a remedial investigation in 1986 and determined the primary potential exposure sources to be groundwater, surface waste piles, and contaminated sediment in Bayou Bonfouca. Based on the results of investigations, EPA and the Louisiana Department of Environmental Quality chose a remedy that involves dredging contaminated sediment from the bayou, excavating contaminated waste piles and soil, and incinerating the solid wastes in a transportable incinerator. The site remedy, which included incineration, was specified in the Record of Decision signed in March 1987.

Of the total 142,000 megagrams (Mg) (157,000 tons) of waste to be incinerated, approximately 119,000 Mg (132,000 tons) consist of hazardous sediment from the bayou; 22,600 Mg (25,000 tons) consist of lightly contaminated soils and waste piles, cellulosic materials, and other miscellaneous wastes on the ground. The solid wastes are primarily low heat content sediment and soils and cellulosic materials with polyaromatic hydrocarbon (PAH) concentrations from milligrams per kilogram (parts per million) levels up to two percent. The dredged bayou sediment will be dewatered in six, 115-cubiometer (150-cubic-yard) plate and frame filter presses before processing in the incinerator. A rotary-kiln-based single train incinerator is deployed at Bayou Bonfouca to process the solid waste feed.

On-site pilot studies indicated that the PAHs in groundwater could be removed by on-site pumping, treatment, and discharge of treated effluent to the bayou. The groundwater treatment plant went on-stream in June 1991. Treatment involves oil/water separation, filtration, carbon bed adsorption, and aeration.

IT Corporation-OH Materials, a joint venture, was awarded a contract in May 1991 and a notice to proceed in February 1992 to remediate and restore the Bayou Bonfouca site. The remediation project includes air quality monitoring and controls, site preparation, dredging and excavation, bayou bank stabilization and monitoring, equipment mobilization and erection, the trial burn, incineration, demobilization, and site closure. The project completed a successful trial burn in November 1993, and the commercial operation began in December 1993. The expected duration of the project is 40 months from mobilization to site closure.     

Bioavailability of calcium from sweetpotato and soy flour supplemented diets in hamsters

The bioavailability of calcium from two varieties of sweetpotatoes and supplementation of sweetpotatoes with soy flour was investigated in hamsters using plasma calcium concentration and femur calcium content as indicators. Five different diets were fed to five groups of animals for 28 days. There was no significant difference in plasma calcium concentrations of hamsters in all the diet groups. However, the femur calcium content of hamsters with transgenic sweetpotato flour (TSPF) and parent nontransgenic (from which transgenic was produced) sweetpotato flour (NTSPF) diets was significantly higher than that of the transgenic sweetotato flour supplemented with soy flour (TSPF + SF) and parent nontransgenic sweetpotato flour supplemented with soy flour (NTSPF + SF) diets. The relative bioavailability of calcium from the control (100%), TSPF+SF (30%), NTSPF+SF (23%), TSPF (57%) and NTSPF (46%) indicated that sweetpotatoes could be the better source of calcium, however, supplementation with soy flour might reduce the bioavailability of calcium.     

Development and evaluation of air pollution–linked quality of life (AP-QOL) questionnaire: insight from two different cohorts

Environmental Science and Pollution Research - In this study, the air pollution–related quality of life (AP-QOL) questionnaire was carried out in two geographically and economically different...     

Mosquito biodiversity of Dibru-Saikhowa biosphere reserve in Assam, India

Entomological surveys were conducted for three consecutive years in core and buffer zone of the Dibru-Saikhowa biosphere reserve in pre monsoon, monsoon and post-monsoon seasons. A total of 52 species of mosquitoes under eleven genera have been detected. The genus Anopheles (18 species) was the predominant followed by Culex, Aedes, Mansonia, Armigeres, Mimomyia, Ochlerostatus, Malaya, Toxorhynchites, Ficalbia and Aedeomyia. The buffer zone of the forest reserve where human habitations are there exhibited the presence of maximum number of species (49 species under 10 genera) in comparison to core zone (42 species under 10 genera). In buffer zone, maximum numbers of species (38) were recorded in monsoon season followed by post- monsoon (35 species) and Pre-monsoon season (34 species). Whereas in core zone, maximum number of species were collected in post monsoon season followed by pre monsoon season and monsoon season. In Core and buffer zone, the maximum species were recorded from the ground pool habitat and slow flowing stream respectively. Among the disease vectors, the potential Japanese encephalitis vectors incriminated in India were very much prevalent. This study provides the list of available mosquito species recorded for the first time in the Dibru-Saikhowa biosphere reserve.     

Effect of combustion variables on PAHs emission from incineration of cellulose waste filters from acrylic industry

Incineration of cellulose waste filter from acrylic industry showed the presence of 13–16 polycyclic aromatic hydrocarbons (PAHs) from the list of 16 priority pollutants with an airflow rate of 1, 2, 3, and 4 L min^???1 in laboratory scale quartz tube vertical incinerator at 700–1,000°C at an interval of 100°C. The amount of total 16 PAHs increases with the increase in temperature with airflow rate of 1 L min^???1 and was found to be 9.4 times at 1,000°C than at 700°C. Studies at 800–1,000°C showed the decrease in total 16 PAHs with increase in airflow rate from 1 to 2 L min^???1. The amount of total 16 PAHs increases at 700, 800, and 1,000°C with increase in airflow rate from 2–4 L min^???1. At 900°C, amount of 16 PAHs decreases with increase in flow rate from 1 to 3 and increases at 4 L min^???1. The lesser amount of 2A PAHs was found at 700–900°C with airflow rates of 1–3 L min^???1, while less amount of 2B PAHs was found at 700°C and 800°C (with airflow rate of 1–2 L min^???1), at 900°C (with airflow rate of 1–3 L min^???1) and at 1,000°C (with airflow rate of 3 L min^???1). However, the sum total of 2A and 2B PAHs were found to be less at 700–900°C with airflow rate of 1–2 L min^???1.     

Metal fractionation study on bed sediments of Hussainsagar Lake, Hyderabad, India

Hussainsagar Lake in the heart of Hyderabad City (India) receives toxic substances through five streams draining from a catchment area of 245 km². Of particular interest are heavy metals received from urban runoff as well as municipal sewage and industrial effluents. Heavy metals entering the lake get adsorbed onto the suspended sediments, which eventually settle down in the bottom of the lake. In this study, fractionation of metal ions has been studied on the bed sediments of Hussainsagar Lake in order to determine the ecotoxic potential of metal ions. Comparison of sediments with average shale values indicated anthropogenic enrichment with copper, nickel, lead, cadmium, and zinc. The risk assessment code as applied to the present study reveals that 10–17% of manganese, 10–18% of nickel, 14–24% of chromium, 10–19% of lead, 21–30% of cadmium, and 18–28% of zinc exist in exchangeable fraction and, therefore, comes under medium risk category and may enter into food chain. The association of these metals with the exchangeable fraction may cause deleterious effects to aquatic life. The present database will help in formulating guidelines for carrying out dredging operations under restoration programs in the Hussainsagar Lake.     

Effect of Grazing and Climatic Changes on Alpine Vegetation of Tungnath,Garhwal Himalaya,India

Effect of grazing and changing climate on vegetation composition of alpine pasture at Tungnath, Garhwal Himalaya was observed. Growth form pattern and phytosociological attributes were analyzed during 1988 under grazed (exposed to extensive grazing) and ungrazed (protected from grazing) conditions. These observations were repeated during 1998. It was observed that number of early growing species and long vegetative growth cycle species had increased at both sites in 1998 in comparison to 1988. Further, some species, viz., Poa alpina, Polygonum spp., Ranunculus hirtellus, Anemone spp., are predominantly found near the timberline-subalpine region. These species are less palatable and were present at both sites with higher dominance (TBC) and niche width in 1998 indicating wide distribution of the species along an altitudinal gradient. These observations indicated the migration of these species towards upper slopes of alpine. Species diversity was also higher after ten years. However, it is clear that climatic changes alone are not responsible for these vegetational shifts. In fact, human-induced changes are the main reason for habitat destruction and changes in vegetation composition of the alpine region of Garhwal Himalaya. Before final conclusions can be made, long-term studies on vegetation composition and changes are needed, especially in Himalayan region.