Life cycle sustainability assessment of optimized biodiesel production from used rice bran oil employing waste derived-hydroxyapatite supported vanadium catalyst

Environmental Science and Pollution Research - The present work encompasses the production of biodiesel from an inexpensive waste, viz., used rice bran oil (URBO) through concurrent esterification...     

Effects of silver nanoparticles on stress biomarkers of Channa striatus: immuno-protective or toxic?

Environmental Science and Pollution Research - Nanotechnology is a novel arena with promising applications in the field of medicine, industry, and agriculture including fisheries....     

Characterization and seasonal distribution of microplastics in the nearshore sediments of the south-east coast of India,Bay of Bengal

• MPs in the coastal sediment of south-east coast of India are quantified. • High MPs are recorded near river mouths and nearshore regions. • Polyethylene and polypropylene are the major polymers observed. • MPs contamination is higher than the values reported elsewhere. In view of increasing Microplastics (MPs) contamination in the marine environment and dearth of baseline data, a study was conducted on the abundance, characterization, and seasonal distribution of MPs in the nearshore sediments of the south-east coast of India. Sediment samples (n = 130) were collected at a distance of 1 km and 10 km from the shore region at varying depths (8–45 m) along the Chennai to Puducherry coast (165 km stretch), representing two seasons, i.e., south-west (July 2019 and July 2020) and north-east (January 2020) monsoons. The average abundance of MPs at the 22 offshore sites along the Chennai to Puducherry coast varied from 9±4.3 to 19±12.9 particles/50 g dry weight, in July 2019 and January 2020, respectively. July 2020 had an average abundance of 10±4.5 particles/50 g dry weight. Spatially, high levels of MPs were found at 1km stations and transects in proximity to the river inlets, and temporally, the north-east month recorded the maximum concentration. The dominant morphotype was the filament, and the major polymers were polyethylene and polypropylene. Scanning Electron Microscope (SEM) images revealed the surface irregularity and degradation of MPs due to weathering. The study highlights that high sediment contamination by MPs occurs during heavy rainfall and accumulates closer to river inlets. Eventually, this study suggests that appropriate management of plastic wastes on the landside will reduce MP contamination in the marine environment.     

Macroporosity and manure influence on atrazine transport through soil

The influence of soil macro-porosity and manure on atrazine (6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine) transport was investigated under laboratory conditions using disturbed and undisturbed soil columns. The macro-porosity in the soil column was obtained with CT scanning technique. Liquid manure was applied at the surface of soil column, 19 cm long and 8 cm in diameter, at a rate of 60 m3/ha. Experimental results revealed that atrazine moves faster through the soils in the presence of manure compared to soil without application of manure. The average time for elusion and the relative peak concentration in the disturbed soil column without manure was 14.5 h and 3.1%, respectively compared to 11.0 h and 6.9% in the presence of manure, respectively. Similar behavior was observed in the case of disturbed soil columns. Soil macro-porosity has shown large impact on atrazine transport, especially in the presence of manure.     

A MULTI-TIER APPROACH FOR AGRICULTURAL WATERSHED MANAGEMENT1

A multi-tier approach for agricultural watershed management has been proposed. The approach involves identification of a watershed management issue/problem, selection or development of simple conceptual model suitable for the exploration of the issue/problem identified and appropriate to the database available, and application of the model the address the identified issue/problem. The procedure is repeated by increasing the complexity in the conceptual model until the identified issue/problem has been addressed satisfactorily. An application of the procedure to an example watershed in southern Ontario conditions is shown. The application example has revealed that for identification of temporal pattern of runoff and sediment loads a simple conceptual model is adequate. For identification of spatial location of the sediment source areas and for the development of a monitoring program for the evaluation of remedial strategies a more complex distributed agricultural watershed model is necessary.     

TARGETING REMEDIAL MEASURES TO CONTROL NONPOINT SOURCE POLLUTION1

ABSTRACT_: The watershed model GAMES is used for the evaluation of a targeting approach to control fluvial sedimentation arising from soil erosion in agricultural areas. The data considered for the analysis consists of output from the application of the model to existing and hypothetical soil and crop management systems in two small watersheds of southern Ontario, one in the rolling uplands and the other in a very flat lowland area. The model output includes estimates of spring sediment yield from field-size cells to the stream outlet for existing agricultural management conditions, and estimates of sediment yield resulting from the successive implementation of two levels of soil erosion controls under four remedial measures strategies. The results reveal that, for the rolling upland watershed exhibiting a wide range of soil erosion and sediment yield rates, targeted control programs can be expected to provide an extremely effective approach to sediment control. For flat lowland watersheds, exhibiting relatively uniform soil erosion and sediment yield rates, the strategy of targeting controls may be somewhat more effective than a random approach to control, but not as efficient as in the case of watersheds in more rolling terrain. It is evident from the study that a screening model such as GAMES provides a very useful tool for the planning and evaluation of erosion and sediment control programs.     

Eco-sanitation and its benefits: an experimental demonstration program to raise awareness in central Nepal

This study focuses on awareness and an experimental demonstration about the use of human urine and wood ash as a fertilizer. This study was conducted in Chanauta, central Nepal, from November 2009 to February 2010. The villagers (N = 27) were asked about their awareness of eco-sanitation and fertilizer value of urine and ash. All the participants agreed that the use of urine and ash was a good idea. In the experimental study, the fertilizer value of urine+ash was compared with animal manure and no-fertilizer in the cultivation of radish, potato, broadleaf mustard, cauliflower, and cabbage. Different plants cultivated plots received 54–81 kgN/ha with urine+ash or manure fertilizer. The urine+ash fertilizer produced significantly (p < 0.05) higher broadleaf mustard biomass than obtained from animal manure and without fertilization. Urine+ash-fertilized plots growing radish, potato, cauliflower, and cabbage produced similar or slightly higher yields biomass compared to those achieved with manure fertilization. This might be because of high P, K as well as greater availability of N in applied urine compared to manure. It is concluded that urine+ash fertilizer can be used instead of animal manure; in this study, a dose of 4 L of urine was equal to 1 kg of dry cattle manure and produced a similar or greater yield of vegetable biomass than manure fertilization. To be able to generalize this conclusion, it is important to conduct these kinds of experiments with different seasonal crops and in other parts of the world.     

Knowledge and awareness of eco-sanitation in central Nepal: a questionnaire survey

This study is based on a visual inspection and a questionnaire survey about sanitation in central Nepal. A total of 201 people from different groups were asked about their knowledge about eco-toilets, the fertilizer value of human urine and wood ash. Farmers were the least educated and least aware of most of the topics asked. Although the majority of educated people were aware about urine fertilizer, 68% of them were not interested in its use in their home, and 39% of them said that it might be not accepted. The visual inspection revealed that environmental hygiene depends on education. It is concluded that farmers need to receive practical demonstrations about the use of eco-toilets and wood ash to appreciate the direct benefits. It can be assumed that since urine fertilizer is a bonus obtained from eco-toilets, this could encourage even poor people to construct these kinds of facilities.     

Application of sensory and microbial analysis to assess quality of fish in Siliguri city of West Bengal, India

Sensory and certain microbial analyses were applied to assess the quality of raw fish sold at a market in Siliguri cityof West Bengal, India. In regular surveys undertaken during June to August 2008, a particular fish species was randomly selected, its source was noted and a sensory analysis, the quality index method (QIM) was applied to assess its quality Raw fish samples were also collected and a small quantity (about 1 g) of scales oran upper layer of the skin surface (forscale-less fish samples), gill, liverand a portion of gut with gut-contents were aseptically removed for enumeration of the total aerobic heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and coliform counts. Oreochromis mossambicus and Tenulosa ilisha recorded significantly higher QIM scores, compared to other species (p<0.05). Riverine fish, Lepidocephalichthys guntea and Channa punctatus scored the lowest QIM scores (0) while scores for Puntius ticto and Mystus vittatus and pond cultured species like Cirrhinus mrigala, Catla catla, Labeo rohita, Labeo bata and Cyprinus carpio were very marginal (p<0.05). Aeromonas spp., Salmonella spp. and total coliforms were recorded from all the studied species while Pseudomonas spp. was isolated from only seven species. Among the tissues examined, the lowest counts of total heterotrophic bacteria, Aeromonas spp., Pseudomonas spp., Salmonella spp. and total coliforms were recorded from the skin in every fish species. Highest counts of pathogenic bacteria (except Pseudomonas spp.) were recorded in Tenulosa ilisha for all the tissues except liver. Since fish are properly cooked in Bengali households, the risk of disease from fish consumption is relatively less. However, some tribes residing in the region are known to consume undercooked fish and proper cooking methods should be followed in view of the present findings to avoid health risks. Besides, utmost care should be taken while handling fish.     

Impact of osmotic stress on seed germination and seedling growth in black gram (Phaseolus mungo)

An experiment was conducted to see the impact of osmotic stress as it is one of the main cause in various soil and water disorders in agricultural field crops, speciallythe seed germination and seedling growth. The osmotic stress was generated using PEG-6000 and the seed germination, seedling growth were evaluated including the status of pigments i.e. chlorophyll (a, b and total), total carotenoids, pheophytin (a, b and total) and different enzymes like amylase, peroxidase, catalase and superoxide dismutase. The various osmotic potentials generated (-2, -5 and -10 bars) showed significant decrease in germination percentage as at the osmotic potential of -10 bars it was observed 70 in comparison to 90% of control. All the seedling growth parameter also showed inhibition with increase in osmotic potential. Increase in osmotic stress decreased Chlorophyll 'a', while Chlorophyll 'b' was increased in -5 bars while total chlorophyll showed decrease in -5 bars osmotic potential. Total carotenoids and pheophytin (a, b and total) were highly increased in -5 bars and decreased in -10 bars osmotic concentration. Enzymatic activity was found to be decreased in amylase while peroixidase, catalase and SOD were increased at different osmotic gradients in comparison to control. The data observed in the experiment can be helpful to assess the impact of any kind of osmotic stress on plant growth and development in crops.