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Determination of Sulphurdioxide (SO2) Distribution in the Eastern Black Sea Region with Geographical Information System
Kaz?m Onur Demirarslan, Halil Ak?nc?
Dogal Afetler ve Cevre Dergisi , 2016, DOI: 10.21324/dacd.91087
Abstract: Air pollution occurs more particularly in areas where there are an intense and unplanned urbanization. Because of the pollution, air quality is reduced and the pollution causes the various health problems. In this study, sulphurdioxide (SO2) concentration distributions has been examined in The Eastern Black Sea region where decreasing air quality because of the non-planned urbanization and topographical reasons. Fossil fuels used for heating especially in the winter season lead to air pollution dramatically. The Black Sea Coast could be one of the major sources of the air pollution in the study area. In this study, the effects and distributions of SO2 polluter on air quality is investigated by produced maps with the help of geographical information systems in the area of Eastern Black Sea zone that has Artvin, Bayburt, Giresun, Gumushane, Ordu, Rize, and Trabzon cities.The related data of air quality, measurement stations which are belonging to The Ministry of Environment and Urbanization, have been used to measure hourly data between 2011-2016 years. The outcomes of this study, the means of SO2 concentrations ranking is found in spring seasons, Ordu > Giresun > Trabzon > Gumushane > Rize > Bayburt > Artvin, in summer seasons, Trabzon > Giresun > Rize > Ordu > Artvin > Bayburt, in fall seasons, Trabzon > Ordu > Gumushane > Giresun > Bayburt > Artvin > Rize, in winter seasons, Ordu > Trabzon > Gumushane > Giresun > Bayburt > Artvin > Rize.
Downward fluxes of sinking particulate matter in the deep Ionian Sea (NESTOR site), Eastern Mediterranean: seasonal and interranual variability  [PDF]
S. Stavrakakis,A. Gogou,E. Krasakopoulou,A. P. Karageorgis
Biogeosciences Discussions , 2013, DOI: 10.5194/bgd-10-591-2013
Abstract: In order to assess seasonal and interranual variability in the export of particulate matter and its main constituents, sediment traps were deployed at five successive depths from February 2006 to March 2010 in the deepest basin of the Mediterranean (SE Ionian Sea, NESTOR site). The average total mass fluxes were 66, 58, 54, 34, and 52 mg m 2 d 1, at 700, 1200, 2000, 3200, and 4300 m, respectively. The interranual variability generally witnesses a gradual increase of fluxes during the experiment. The temporal variations of the mass flux showed similar seasonal signal at all sampling depths with higher values in spring–summer and lower in autumn–winter. Changes in the main constituents of the mass flux (organic carbon, carbonates, opal, and lithogenic matter) largely followed the same temporal variability with mass flux, revealing mechanisms of rapid vertical (top-down) transport from 700 m down to 4300 m-depth. Lateral inputs at the deepest trap are probably of importance, attributed to the influence of the deep Adriatic water, characterized by relatively higher turbidity than overlying water masses. The Ionian Sea displays high seasonal variability with maximum productivity rates observed during the late winter/spring convective mixing period. Our flux study proposes two additional processes, potentially of high importance for fuelling surface waters with nutrients at the NESTOR site: (1) the upwelling of intermediate waters in late spring-early summer, causing nutrient inputs in the surface layer which may lead to episodes of increased productivity, as witnessed by the organic carbon, carbonate, and opal fluxes in the mesopelagic and bathypelagic layers and (2) the influence of episodic dust input events, leading to enhanced fluxes of lithogenic matter.
15N enrichment in the surface Particulate Organic Nitrogen of the north-eastern Arabian Sea from the middle to the waning phase of the winter monsoon: possible causes  [PDF]
S. Kumar,R. Ramesh
Ocean Science Discussions (OSD) , 2007,
Abstract: A temporal increase of ~5‰ in the average nitrogen isotopic composition (δ15NPON) of surface particulate organic nitrogen was observed in the open north-eastern Arabian Sea during January to late February-early March 2003, despite the presence of T. erithraeum (up to ~11%), a diazotroph that fixes atmospheric N2, in the latter period. Hydrographic conditions and residence time of nitrate in the water column suggested that this increase could be a combined effect of denitrification in the subsurface layer and inefficient utilization of nitrate entrained in the water column during January.
GEOGRAPHICAL ANALYSIS OF THE COASTAL FLORA OF THE AZOV SEA
Kolomiychuk V. P.
Bìologì?nij Vìsnik Melìtopol?s?kogo Der?avnogo Pedagogì?nogo Universitetu ìmenì Bogdana Hmel?nic?kogo , 2012,
Abstract: Quantitative indicators of the coastal flora of the Azov Sea are presented. Geographical features of the flora of the region have been analyzed. The major endemic complexes of the flora being investigated are described.
CFD Modeling of Particulate Matter Dispersion from Kerman Cement Plant
A. Alizadehdakhel,A. Ghavidel,M. Panahandeh
Iranian Journal of Health and Environment , 2010,
Abstract: "n "n "nBackgrounds and Objectives: The dispersion of particulate matter has been known as the most serious environmental pollution of cement plants. In the present work, dispersion of the particulate matter from stack of Kerman Cement Plant was investigated using Computational Fluid Dynamics (CFD) modeling."nMaterials and Methods: In order to study the dispersion of particulate matter from the stack, a calculation domain with dimensions of 8000m × 800m × 400m was considered. The domain was divided to 936781 tetrahedral control volumes. The mixture two-phase model was employed to model the interaction of the particulate matter (dispersed phase) and air (continuous phase). The Large Eddy Simulation (LES) method was used for turbulence modeling."nResults: The concentration of particulate matter in the whole calculation domain was computed. The predicted concentrations were compared to the measured values from the literature and a good agreement was observed. The predicted concentration profiles at different cross sections were analyzed."nConclusion:The results of the present work showed that CFD is a useful tool for understanding the dispersion of particulate matter in air. Although the obtained results were promising, more investigations on the properties of the dispersed phase, turbulent parameters and the boundary layer effect is needed to obtain more accurate results.
Simulations of dispersion and deposition of coarse particulate matter  [PDF]
Rodolfo G. Cionco,Nancy E. Quaranta,Marta G. Caligaris
Physics , 2012,
Abstract: In order to study the dispersion and deposition of coarse anthropogenic particulate matter (PMc, aerodynamic diameters> 10 mm), a FORTRAN simulator based on the numerical integrator of Bulirsch and Stoer has been developed. It calculates trajectories of particles of several shapes released into the atmosphere under very general conditions. This first version, fully three-dimensional, models the meteorology under neutral stability conditions. The simulations of such pollutants are also important because the standard software (usually originating in the United States Environmental Protection Agency-EPA-) describe only the behavior of PM10 (diameter less than 10 mm). Bulirsch and Stoer integrator of widespread use in astrophysics, is also very fast and accurate for this type of simulations. We present 2D and 3D trajectories in physical space and discuss the final deposition in function of various parameters. PMc simulations results in the range of 50-100 mm and densities of 5.5 g cm-3 emitted from chimneys, indicate that for the purpose of deposition, the emission velocities are not as important as wind speed and the shape of the particles. For densities less than 2 g cm-3, the lack of consideration of buoyancy introduces important changes in the distribution of deposited PMc.
Organic geochemical studies of sinking particulate material in China sea area II
Yi Duan,Mingzhong Cui,Lanhua Ma,Jinming Song,Shixin Zhou,Binjie Luo
Chinese Science Bulletin , 1997, DOI: 10.1007/BF02882785
Abstract: We have for the first time studied the compositions of ketone, aldehyde and alcohol lipid compounds in sinking particulate materials from Yongshu Reef lagoon and the continental shelf of the East China Sea collected by sediment trap sampling apparatus. The results indicate that sinking particulate materials contain abundant isoprenoid ketone, aldehyde and alcohol lipid compounds which take part in marine chemical cycling. The compositional features of these compounds show that sinking particulate organic matter mainly comes from autochthonous marine organisms and Yongshu Reef lagoon has more submerged macrophytes-derived component, while the continental shelf of the East China Sea contains more dinoflagellate-derived constituent. The contribution of higher land plant to sinking particulate organic matter may be very small. In contrast, it is greater in Yongshu Reef lagoon than that in the continental shelf of the East China Sea. Sinking particulate organic matter in the two regions undergoes strong biochemical transformation processes before reaching the depth of 5 m to the sea floor, and its intensity is greater in Yongshu Reef lagoon than in the continental shelf of the East China Sea. These results have certain reference value to the researches of marine chemistry, marine biology and marine sedimentology in China, and reveal the importance of organic geochemistry to the study of oceanology.
Deposition of organic matter and particulate nitrogen and phosphorus at the North Sea-Baltic Sea transition - a GIS study  [cached]
Ditte L. Jansen,Dorte P. Lundqvist,Christian Christiansen,Lars C. Lund-Hansen
Oceanologia , 2003,
Abstract: A GIS (Geographical Information System) based study on deposition in the North Sea-Baltic Sea transition area has been carried out. The study is based on (i) a digital bathymetry model, (ii) 93 available 210Pb / 137Cs sedimentation rate estimations, (iii) grain-size distributions, organic matter, C, N and P content of 64 top 1 cm sediment samples from the study area, and (iv) GIS-based modelling of resuspension potentials based on wind statistics. With the use of regression statistics on depth, resuspension potential and sediment characteristics, results are extrapolatedarea-wide from the 64 sampling positions. The area is divided into sediment types and classified as accumulation or erosion/transport bottoms. Model results show good agreement with existing maps of sediment distributions, indicating that the sediment distribution is governed to a large extent by wind-induced waves. Correlations of sediment types, their deposition rates and their N and P contents were used to estimate spatial deposition rates. In all, the yearly deposition in the study area amounts to 2.8 million tons of organic matter, 0.14 million tons of total nitrogen, and 0.035 milliontons of total phosphorus. Correlations of sediment types and dry bulk densities were used to infer spatial inventories of organic matter and total nitrogen and phosphorus in the top 1 cm of the sediments. A total of 100 million tons of organic matter, 4 million tons of total nitrogen, and 0.019 million tons of total phosphorus are contained in the top 1 cm of the sediments in the study area. In general, the deep parts of the study areawith low resuspension potentials act as sinks for the fine-grained sediments and their associated particulate nutrients.
Geographical persistence of surface-layer water properties in the Archipelago Sea, SW Finland  [PDF]
Tapio Suominen,Harri Tolvanen,Risto Kalliola
Fennia : International Journal of Geography , 2010,
Abstract: The Archipelago Sea in the Northern Baltic Sea has a complex water quality regime. The region consists of islands and underwater thresholds that separate interconnected sub-basins, where the waters from the adjacent sea areas and discharges from the mainland are mixed. Thus, the water properties in the region are exceptionally varying by season and location. We studied the seasonal developments of five surface-layer water variables – temperature, salinity, Secchi depth, chlorophyll and acidity – and the persistence of their geographical patterns in a network of 20 sampling stations in the eastern part of the Archipelago Sea during a period from May to October in 2007. Furthermore, the inter-annual persistence of the late summer observations of three of these variables were analysed within the same network. Although preconceptions about the general gradation patterns from the mainland towards the open sea were found realistic, we also identified geographically divergent seasonal developments and found out that the inter-annual persistence of the studied three variables were not geographically as strong as expected.
Quantification of Dissolved and Particulate Polyunsaturated Aldehydes in the Adriatic Sea  [PDF]
Charles Vidoudez,Raffaella Casotti,Mauro Bastianini,Georg Pohnert
Marine Drugs , 2011, DOI: 10.3390/md9040500
Abstract: Polyunsaturated aldehydes (PUA) are supposed to play critical roles in chemically-mediated plankton interactions. Laboratory studies suggest that they act as mediators of chemical defense and chemical communication. PUA are oxylipins containing an α,β,γ,δ-unsaturated aldehyde structure element and are mainly found in diatoms. We present here a detailed surface mapping of PUA during a spring bloom of the diatom Skeletonema marinoi in the Adriatic Sea. We monitored dissolved PUA, as well as particulate PUA, which are produced by phytoplankton after cell disintegration. Our survey revealed a patchy distribution of PUA and shows that at most stations S. marinoi is the major contributor to the overall PUA. Our data also suggest that lysis of a diatom bloom can contribute significantly to the dissolved PUA concentrations and that other producers, which are smaller in cell size compared to diatoms, have to be taken into account as well if the total PUA content of marine samples is considered. The analyses of samples collected in deeper water suggests that diatom contribution to PUA decreases with depth, while smaller-sized unidentified organisms take place as dominant contributors to the PUA concentrations.
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