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Environmental pollution and geo-ecological risk assessment of the Qhorveh mining area in western Iran
2019
Saedpanah, Safoura | Amanollahi, Jamil
In order to evaluate the effect of mining activity on the environment of the Qhorveh mining area in the west of Iran, the geological, ecological and environmental data, related to social development and regional economic status, were used. The geological data included seven sub-indices, such as vegetation coverage, land utilization type, and fault activity; ecological data, with two sub-indices, such as degree of ecological environment recovery; and finally, environmental data, with three sub-indices, such as soil and dust pollutions. These were selected based on the literature and expert opinion which were utilized for environmental pollution and geo-ecological (EPGE) risk assessment of the study site. Remote sensing (RS) image, field sampling, digital elevation map, and data retrieved from different government agencies were used to generate layers for the sub-indices in the geographic information system (GIS) environment. In addition, the analytical hierarchy process (AHP) method was used to determine the weight of sub-indices. Five levels consisting of best, good, middle, poor and worst were used to describe the EPGE risk assessment of the Qhorveh mining area. Results showed that worst and poor levels of EPGE risk are in the east and northeast of the study area where the gold and pumice mines are located while best and good levels of EPGE risk are in its center where the stone mines are located. According to the results of this research, the EPGE risk assessment of the Qhorveh mining area is affected by the environmental pollution index with its highest weight (0.3908). It can be concluded that the integration of the RS, GIS and AHP methods proposed in this study improved the evaluation quality of EPGE risk assessment.
Показать больше [+] Меньше [-]Animal size impacts perfluoroalkyl acid (PFAA) concentrations in muscle tissue of estuarine fish and invertebrate species
2020
Taylor, Matthew D.
Environmental emissions of perfluoroalkyl acids (PFAAs) often contaminate aquatic ecosystems and accumulate in the species therein. This can represent an exposure pathway for human populations where seafood is consumed. Concentrations of PFAAs in water breathing animals may be a function of many different factors, however, little is known about how these different factors impact contaminant accumulation in estuarine and marine species. This study explores the relationships between PFAA accumulation and two key variables, animal size and sediment concentrations, for a number of important seafood species. Sixty Dusky Flathead (Platycephalus fuscus), 58 Mulloway (Argyrosomus japonicus) and 53 Giant Mud Crab (Scylla serrata) were tested for perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA) and perfluorohexane sulfonate (PFHxS) in edible tissues, and the concentrations compared with animal size and sediment concentrations at the location of capture. PFAAs showed a high degree of variation among species, and PFOA and PFHxS were only common in Giant Mud Crab. Log-transformed PFOS concentrations in all three species showed negative correlations with animal size (weight). There was limited evidence for relationships between PFOS muscle tissue concentration and sediment PFOS concentration. The patterns observed are potentially explained by changes in trophic position, relative growth rate, consumption rate and metabolic rate, throughout the species life history. The results contrast with observations for other persistent organic pollutants, whereby larger individuals tend to carry greater contaminant loads. Future work is required to establish whether these patterns are evident for PFAAs in other species and contaminant sources.
Показать больше [+] Меньше [-]Allometric relationships to liver tissue concentrations of cyclic volatile methyl siloxanes in Atlantic cod
2014
Warner, Nicholas A. | Nøst, Therese H. | Andrade, Héctor | Christensen, Guttorm
Spatial distribution and relationship of allometric measurements (length, weight and age) to liver concentrations of cyclic volatile methyl siloxanes (cVMS) including octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclosiloxane (D6) in Atlantic cod (Gadus morhua) collected near the community of Tromsø in Northern Norway were assessed. These congeners were benchmarked against known persistent polychlorinated biphenyls (PCBs 153 and 180) to assess accumulation behavior of cVMS. D5 was the dominate cVMS detected in all fish livers with lipid normalized concentrations up to 10 times or greater than those observed for PCB 153 and 180. D4 and D6 concentration were negatively correlated with fish length and weight, indicating a greater elimination capacity compared to uptake processes with increasing fish size for these chemicals. These results indicate relationships between allometric measurements and cVMS concentrations may account for concentration variations observed within fish and should be assessed in future studies evaluating cVMS bioaccumulation potential.
Показать больше [+] Меньше [-]Polycyclic aromatic hydrocarbons in commercial fish and lobsters from the coastal waters of Madagascar following an oil spill in August 2009
2011
Rumney, Heather S. | Laruelle, Franck | Potter, Kerry | Mellor, Philip K. | Law, Robin J.
Concentrations of polycyclic aromatic hydrocarbons were determined in species of commercial fish and lobsters following an oil-spill just off the protected Madagascan coastline. Samples were collected along the coastline within and outside the affected area. Summed PAH concentrations ranged from 1.9μgkg⁻¹ to 63μgkg⁻¹ wet weight, but with no higher molecular weight PAHs (>202Da) being detected. All concentrations of benzo[a]pyrene, benz[a]anthracene and dibenz[a,h]anthracene were <0.1μgkg⁻¹ wet weight, well within the EU and UK set limits for the protection of human health. Additionally, samples were calculated as the benzo[a]pyrene toxic equivalency quotient (TEQ) and found to be well below the level of concern in relation to health of human consumers. Evaluation of the biota PAH data indicated the origin of PAH was predominantly petrogenic with >80% arising from oil sources. Profile studies indicate a low-level multisource petrogenic contamination probably representing a pre-spill background for the area.
Показать больше [+] Меньше [-]Sewage organic markers in surface sediments around the Brazilian Antarctic station: Results from the 2009/10 austral summer and historical tendencies
2012
Martins, César C. | Aguiar, Sabrina Nart | Bícego, Márcia C. | Montone, Rosalinda C.
The discharge of sewage into the Antarctic marine environments by scientific stations has resulted in local changes in these pristine sites. To assess the distribution and concentration of sewage indicators from the Brazilian Antarctic station, sediments were sampled during the 2009/10 austral summer at four points (water depth of 20 and 60m). Concentrations of faecal sterols and linear alkylbenzenes (LABs) ranged from <0.01 to 0.17μgg⁻¹ and <1.0 to 46.5ngg⁻¹ dry weight, respectively. Maximum concentration of faecal sterols was similar to the value previously calculated as the background level for this area (0.19μgg⁻¹), and it is lower than the concentration observed in previous studies (1997–2008), whereas the LABs concentrations remained practically constant (35ngg⁻¹). Despite the low concentrations of sewage markers, the permanent human activities in the region require monitoring programs to determine continuing trends and prevent the increase of anthropogenic impacts.
Показать больше [+] Меньше [-]Length-weight relationship of the most common cephalopod species in Montenegrin trawl | Dužinsko-težinski odnos najzastupljenijih vrsta cephalopoda u kočarskom ribolovu na Crnogorskom primorju
2011
Ikica, Z., Institut za biologiju mora, Kotor (Montenegro) | Kasalica, O., Institut za biologiju mora, Kotor (Montenegro) | Mandić, M., Institut za biologiju mora, Kotor (Montenegro) | Đurović, M., Institut za biologiju mora, Kotor (Montenegro)
A length-weight relationship (LW) for five cephalopod species, of which three decapod (Illex coindetii, Loligo vulgaris, Sepia officianlis) and two octopod species (Eledone cirrhosa, Eledone moschata) is given in this paper. The mean exponent b was found to be significantly lower than 3.
Показать больше [+] Меньше [-]Effects of crown decline on increment in Norway spruce (Picea abies (L.) Karst) in southern Sweden
1989
Bjoerkdahl, G. | Eriksson, H. (Swedish Univ. of Agricultural Sciences, Garpenberg (Sweden). Dep. of Forest Yield Research)
Dynamics of shoot growth in two Calamagrostis villosa stands of the Kehyne Mts. [Czech Republic]
1995
Holub, P. (Akademie Ved, Brno (Czech Republic). Ustav Ekologie Krajiny)
Annual production and turnover rate of underground biomass in Calamagrostis villosa and Avenella flexuosa (Bily Kriz, Beskids) [Czech Republic]
1995
Fiala, K. (Akademie Ved, Brno (Czech Republic). Ustav Ekologie Krajiny)
Comparison study of anatomical and morphological structure of spruce and fir needles in the Beskids Mts. [Czech Republic]
1995
Bednarova, E. (Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Lesnicka a Drevarska Fakulta)