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Metals Contamination in Edible Carnivorous Fishes of Arabian Sea  [PDF]
Rafia Azmat,Rukhsana Talat
Journal of Applied Sciences , 2006,
Abstract: A potential hazard to Clifton beach Karachi was revealed due to accumulation trend of heavy metals in fishes of Arabian Sea with oil pollution by Tasman spirit. Concentration of heavy metals like Hg, Cd, Cr, Pb and As were determined in five common edible carnivorous fishes to calculate the accumulation factor and to establish a basis for environmental protection. The measurements of the metal levels were carried out using atomic absorption spectroscopy. The metal accumulation in the liver, gill, gut and gonads were found to be quite high in comparison with the muscle. All metals studied alter gill filament structure but Pb damage was more prominent
Echinoderms Epizoic on Gorgonian Corals from Karachi Coast  [PDF]
Qaseem Tahera
Pakistan Journal of Biological Sciences , 2001,
Abstract: Three species of the genus Ophiothela and a single specie each of Ophiactis and Asterina belonging to the families Ophiotrichidae, Ophiactidae and Asterinidae respectively epizoic on gorgonian corals were studied. These were recorded from the Karachi coast North Arabian Sea. A brief account of each specie is given with special reference to Ophiothela hadra which is new to this region
Sphaeroma walkeri Stebbing, 1905 in the coastal waters of Karachi (Northern Arabian Sea)  [PDF]
Naseem Ghani,Qadeer Mohammad Ali
Journal of Biological Sciences , 2001,
Abstract: Sphaeroma walkeri Stebbing, 1905 is a new record from the northern Arabian sea. A brief description and some illustrations are given.
Contamination of water and sediments by obsolete pesticides at Vikuge farm, Kibaha distric, Tanzania
MJ Mihale, MA Kishimba
Tanzania Journal of Science , 2004,
Abstract: Sediments and water from Vikuge State Farm, Coast Region, Tanzania, where, in 1986, a “donation” of 170 m3 of partially expired pesticides were stored in an open shed- which eventually collapsed, were analysed for 80 different pesticide residues and metabolites. DDT and HCH, two of the most persistent organochlorines pesticides, were the most dominant pesticides found in both matrices. In sediments the levels were up to 99,620 mg/kg dry weight of ΣDDT and up to 7,400 mg/kg dry weight of ΣHCH. The mean total HCH concentrations were 0.95 μg/l in tap water, 0.28 μg/l in surface water and 3.09 μg/l in ground water. Of the four common HCH isomers,α-HCH and β-HCH had the highest on average concentrations in the water. Mean total DDT concentrations were 1.76 μg/l in tap water, 0.18 μg/l in surface water and 9 μg/l in ground water. The only other pesticides detected were in sediments and water are azinphos-methyl, an organphosphorous insecticide and thiabendazol, a systemic fungicide, respectively. During the rainy season, the well-water, which is used for domestic purposes by the villagers, has levels of pesticides higher than those allowed by WHO for drinking water. It is thus recommended that immediate decontamination measures be undertaken. In the meantime, villagers should sediment the well-water and should not use not use it at all during the rainy seasons.. Tanzania Journal of Science Vol. 30 (2) 2004: pp. 21-32
Overcoming of Soil Contamination with Pesticides in Forest Nurseries Using the Activity of Microorganisms
Irina A. Freiberg,Svetlana K. Stetsenko
Pesticidi i Fitomedicina , 2010,
Abstract: The use of pesticides during cultivation of pine seedlings in forest nurseries resultsin the formation two phenotypes of teratomorph seedlings – conditionally normal andabnormal. Growing forest cultures from teratomorph seedlings leads to their low survivalrate. It is known that pesticides and their metabolic products can remain in soil for manyyears. It is therefore impossible to rely only on natural degradation of pesticides in soil. Apromising way of removing pesticides from soil is their microbiological decomposition.This method is preferable because there is a meliorative organic substance not far from forestnurseries – i.e. forest litter rich in microorganisms. The purpose of these experimentswas to examine the influence of forest litter applied on pesticide decomposition in soil andmorphology of pine seedlings. The rates of forest litter that were most effective in decompositionof pesticides and the activity of microbial communities in litter, depending on foreststand structure, were determined. Estimation of that action was based on the morphologyof seedlings (rate of pine seedlings with normal, conditionally normal and abnormalphenotypes), intensity of CO2 emission from soil and catalase activity, which correlates withthe number of soil microorganisms. The results of these experiments showed the mosteffective activity of forest litter at the application rate of 20 kg/m2. The number of seedlingswith normal phenotype rose from 32% up to 40%. Besides, it was noted that saprophyteswere most effective in pine forest litter, which is characterized by a more acid reaction ofsoil solution, while most others were rich in fungi. The highest number of normal phenotypeseedlings, intensity of CO2 emission and activity of soil catalase were correlated withthe microbiological activity of the applied pine forest litter.
Risk estimate of water contamination by pesticides used in coffee crops
Soares, Alexandra F. S.;Le?o, M?nica M. D.;Vianna Neto, Márcio R.;Oliveira, Sílvia M. A. C.;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2012, DOI: 10.1590/S1415-43662012000400013
Abstract: a study was conducted in manhua?u city, minas gerais, aiming to study the effects of pesticides used in coffee crops on surface and ground waters. manhua?u is located in an important brazilian region of agricultural production. moreover, the city possesses many different water sources directed to the public water supply, and 13 points of surface and groundwater pumping. there have also been several occurrences of cancer in the local population. a survey conducted among cities of minas gerais identified 122 cities with high occurrences of death due to cancer, among which was manhua?u. the physico-chemical properties and applied mass of the active ingredients of each pesticide studied were surveyed. goss and gus algorithms were applied to estimate the risk of surface and ground water contamination, respectively. some of the most widely used pesticides in the region, whose contamination potential was estimated as high, were later detected in surface waters through lc/ms-ms. this study can help agriculturists and officials of environmental organizations select and control, respectively, less harmful products to the water.
Contribution to Surface Water Contamination Understanding by Pesticides and Pharmaceuticals, at a Watershed Scale  [PDF]
Stéphanie Piel,Estelle Baurès,Olivier Thomas
International Journal of Environmental Research and Public Health , 2012, DOI: 10.3390/ijerph9124433
Abstract: This study aims at understanding the presence of regulated and emerging micropollutants, particularly pesticides and pharmaceuticals, in surface water, regarding spatial and temporal influences at a watershed scale. The study of relations between micropollutants and other water quality and hydroclimatic parameters was carried out from a statistical analysis on historical and experimental data of different sampling sites from the main watershed of Brittany, western France. The outcomes point out the influence of urban and rural areas of the watershed as well as the impact of seasons on contamination variations. This work contributes to health risk assessment related to surface water contamination by micropollutants. This approach is particularly interesting in the case of agricultural watersheds such as the one studied, where more than 80% of surface water is used to produce drinking water.
Occurrence of Panulirus ornatus Fabricius from Coastal Waters of Karachi
Meher Fatima
Pakistan Journal of Biological Sciences , 2000,
Abstract: The present study reports the occurrence of the spiny lobster, Panulirus ornatus (Fabricius) in coastal waters of Karachi and thus extends its known distribution for Northern Arabian Sea. Information on size of eggs and egg mass is also reported.
Heavy Metal Contamination and Risk Assessment in the Marine Environment of Arabian Sea, along the Southwest Coast of India
American Journal of Chemistry , 2012, DOI: 10.5923/j.chemistry.20120204.03
Abstract: Marine ecosystem is being threatened by the discharge of untreated sewage wastes and industrial effluents which ultimately affects the sustainability of living resources and public health. These wastes carry enormous level of toxicants especially the heavy metals have the tendency to accumulate into the basic food chain and move up through the higher trophic level and results in negative impact on the marine resources thus causing economic loss. In this regard, to ascertain the level of heavy metals in water, particulate, zooplankton (Zn, Mn, Pb, Cu, Cd and Hg) and in sediment (Pb, Al, Cd and Hg) along southern Kerala coast, India has been evaluated during early 2006. The heavy metal concentrations followed the hierarchy; Zn>Mn>Pb>Cu>Cd>Hg; Pb>Zn>Mn>Cu>Cd>Hg; Zn>Pb>Mn>Cu>Cd>Hg and Pb>Al>Cd>Hg in seawater, particulate matter, zooplankton and sediment respectively. The results revealed that in all the transacts (except Cochin) the heavy metal concentrations are below the threshold levels associated with the toxicological effects and the regulatory limits. Metal enrichments were observed close to the major urban areas of coastal waters, mostly associated with large scale industrialization. Enrichment factor, geoaccumulation index and pollution load index were calculated to evaluate the heavy metal threats along the coastal sediment. It revealed minor to moderately severe enrichment of Cd, Pb and Hg in the industrial zones of the coastal stretches especially at Cochin. A comparison with sediment quality guideline quotient indicated that there may be probability of ecotoxicological threats to the benthic community along Cochin transect.
Investigation of Channel Modeling and Simulation of OFDM Based Communication Near Northern Regions of Arabian Sea  [cached]
Rehan Khan,Qiao Gang,Asim Ismail,Khurram Mehboob
Research Journal of Applied Sciences, Engineering and Technology , 2013,
Abstract: Wideband nature of oceanic channel when dealing with multicarrier acoustic subcarriers introduces severe Doppler shifts, little variations may cause overlapping of subcarriers such that entire signal can get completely distorted. Therefore, one of the major problems in OFDM based underwater acoustic communication is the sensitive nature of wideband acoustic subcarriers. In this study, Bellhop beam tracing is used to model two regions in the north of Arabian Sea and the two-step receiver algorithm is used over these channel models. Multipath with delay channel model is obtained using the Bellhop ray tracing algorithm while random Doppler shift is induced in MATLAB on each block and also in the complete OFDM packet. In the first step, resembling converts a wideband problem in to narrowband problem and in the second step; high resolution Carrier Offset Frequency (CFO) tracking compensates the residual Doppler. Cyclic Prefix (CP) OFDM scheme based on block-by-block processing is deliberated here for fast varying channel. In the proposed algorithm, null subcarriers are facilitated for Doppler removal while pilot bits are used for Least Square (LS) channel estimation. Simulation on MATLAB is carried out on both channels, i.e., near Gawadar Coast and Karachi Harbor; satisfactory results are achieved in terms Low Bit Error Rates (BER) even in high relative speed between transmitter and receiver. These results further suggested and make convinced for the experimental test/ trials, specifically in the region of north Arabian Sea.
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