Heavy metals contamination levels at the Coast of Aliağa (Turkey) ship recycling zone   总被引：1，自引：0，他引：1  

Neşer G  Kontas A  Unsalan D  Uluturhan E  Altay O  Darılmaz E  Küçüksezgin F  Tekoğul N  Yercan F 《Marine pollution bulletin》2012,64(4):882-887

Alia?a Bay is one of the most important maritime zones of Turkey where shipping activity, shipbreaking industry, steel works and petrochemical complexes exist together. Concentrations of heavy metals and organic carbon in sediment of the Alia?a Bay were investigated to evaluate an environmental risk assessment from metals contamination in 2009-2010. Comparison of the metal concentrations with average shale and Mediterranean background levels revealed that most of the samples from the Alia?a were polluted with Hg, Cd, Pb, Cr, Cu, Zn, Mn and Ni. It was found that Hg, Pb, Cu, Zn and Ni levels in Alia?a Bay exceeded the PEL values. Sediments, contaminated with Pb, Cr, Cu, Zn and Ni were considered as heavily polluted per the SQG.  相似文献   

A Study: Removal of Cu(II), Cd(II), and Pb(II) Ions from Real Industrial Water and Contaminated Water Using Activated Sludge Biomass     

Erdal Kusvuran  Deniz Yildirim  Ali Samil  Osman Gulnaz 《洁净——土壤、空气、水》2012,40(11):1273-1283

This study aims to remove of Cu²⁺, Cd²⁺, and Pb²⁺ ions from solution and to investigate the adsorption isotherms, adsorption kinetics, and ion‐exchange affinities of these metals using waste activated sludge (AS) biomass. The adsorptions of the metals on biomass were optimal at an acidic pH value of 6.0 based on its monolayer capacities. Maximum monolayer capacities of AS biomass (q_max) were calculated as 0.478, 0.358, and 0.280 mmol g^?1 for Cu²⁺, Cd²⁺, and Pb²⁺, respectively, and the adsorption equilibrium time was found as 60 min for each metal. The adsorbed amount of metal rose with increasing of initial metal ion concentration. The equilibrium adsorption capacity of AS for initial 0.25 mmol L^?1 metal concentration was determined as 0.200, 0.167, and 0.155 mmol g^?1 for Cu²⁺, Cd²⁺, and Pb²⁺ ions, respectively. These relevant values were determined as 0.420, 0.305, and 0.282 mmol g^?1 for Cu²⁺, Cd²⁺, and Pb²⁺ ions, respectively, when initial metal concentration was 0.50 mmol L^?1. In the multi‐metal sorption system, the adsorption capacity of AS biomass was observed in the order of Cu²⁺ > Cd²⁺ > Pb²⁺. In the presence of 100 mmol L^?1 H⁺ ion, the order of ion‐exchange affinity with H⁺ was found as Cu²⁺ > Cd²⁺ > Pb²⁺. The adsorption kinetics were also found to be well described by the pseudo‐second‐order and intraparticle diffusion models. Two different rate constants were obtained as k_i1 and k_i2 and k_i1 (first stage) was found to be higher than k_i2 (second stage).  相似文献   

Downscaled simulations of the ECHAM5, CCSM3 and HadCM3 global models for the eastern Mediterranean–Black Sea region: evaluation of the reference period     

Deniz Bozkurt  Ufuk Turuncoglu  Omer Lutfi Sen  Baris Onol  H. Nuzhet Dalfes 《Climate Dynamics》2012,39(1-2):207-225

The outputs of three GCMs, ECHAM5, CCSM3 and HadCM3, are downscaled for the eastern Mediterranean–Black Sea region for the period 1961–1990 using a regional climate model, RegCM3, to assess the capability of these models in simulating the climatology of the region. In addition, the NCEP/NCAR Reanalysis data are also downscaled for the same period to display the performance of the regional climate model for the same region, which constitutes a relatively complex terrain and rich variety of climates. The gridded observational dataset of CRU is primarily used in the evaluation of the models, however, a regional dataset, which is based on a relatively dense gauging network, is also used to see how it affects the performance measures of the models. The reanalysis simulation indicates that RegCM3 is able to simulate the precipitation and surface temperature as well as the upper level fields reasonably well. However, it tends to overestimate the precipitation over the mountainous areas. All three GCM models are found to be highly skilled in simulating the winter precipitation and temperature in the region. The two models, ECHAM5 and HadCM3, are also good at simulating the summer precipitation and temperature, but the CCSM3 simulation generates dryer and warmer conditions than the observations for the whole region, which are most likely a result of the dryness in the upper levels of the original outputs. The use of the regional observational dataset does not necessarily improve the pattern correlations, but it yields better match between the modeled and observed precipitation in terms of variability and root-mean-square difference. It could be said that the outputs of these GCMs can be used in the climate change downscaling and impact assessment studies for the region, given that their strengths and weaknesses that are displayed in the present study are considered.  相似文献   

A spectral approach to estimation and smoothing of continuous spatial processes     

Z. T. Yucel  R. H. Shumway 《Stochastic Environmental Research and Risk Assessment (SERRA)》1996,10(2):107-126

This paper is concerned with developing computational methods and approximations for maximum likelihood estimation and minimum mean square error smoothing of irregularly observed two-dimensional stationary spatial processes. The approximations are based on various Fourier expansions of the covariance function of the spatial process, expressed in terms of the inverse discrete Fourier transform of the spectral density function of the underlying spatial process. We assume that the underlying spatial process is governed by elliptic stochastic partial differential equations (SPDE's) driven by a Gaussian white noise process. SPDE's have often been used to model the underlying physical phenomenon and the elliptic SPDE's are generally associated with steady-state problems.A central problem in estimation of underlying model parameters is to identify the covariance function of the process. The cumbersome exact analytical calculation of the covariance function by inverting the spectral density function of the process, has commonly been used in the literature. The present work develops various Fourier approximations for the covariance function of the underlying process which are in easily computable form and allow easy application of Newton-type algorithms for maximum likelihood estimation of the model parameters. This work also develops an iterative search algorithm which combines the Gauss-Newton algorithm and a type of generalized expectation-maximization (EM) algorithm, namely expectation-conditional maximization (ECM) algorithm, for maximum likelihood estimation of the parameters.We analyze the accuracy of the covariance function approximations for the spatial autoregressive-moving average (ARMA) models analyzed in Vecchia (1988) and illustrate the performance of our iterative search algorithm in obtaining the maximum likelihood estimation of the model parameters on simulated and actual data.  相似文献   

Spatial variability of chilling temperature in Turkey and its effect on human comfort     

H. Toros  A. Deniz  L. Şaylan  O. Şen  M. Baloğlu 《Meteorology and Atmospheric Physics》2005,88(1-2):107-118

Summary Air temperature, absolute humidity and wind speed are the most important meteorological parameters that affect human thermal comfort. Because of heat loss, the human body feels air temperatures different to actual temperatures. Wind speed is the most practical element for consideration in terms of human comfort. In winter, due to the strong wind speeds, the sensible temperature is generally colder than the air temperature. This uncomfortable condition can cause problems related to tourism, heating and cooling. In this study, the spatial and temporal distributions of cooling temperatures and Wind Chill Index (WCI) are analyzed for Turkey, and their effect on the human body is considered. In this paper, monthly cooling temperatures between October and March in the years 1929 to 1990 are calculated by using measured temperature and wind speed at 79 stations in Turkey. The influence of wind chill is especially observed in the regions of the Aegean, west and middle Black Sea and east and central Anatolia. The wind chill in these regions has an uncomfortable effect on the human body. Usually, the WCI value is higher in western, northern and central Anatolia than in other regions.  相似文献   

The ecological consequences of level changes in Lake Van   总被引：1，自引：0，他引：1  

O. Deniz  M. Z. Yildiz 《Water Resources》2007,34(6):707-711

Measurements of perennial time scale in Lake Van, the biggest lake with soda in the world, historical data, and the morphological changes in its coasts suggest that there is a continual rise in its level. The rise in the level of the lake which occurs under natural conditions averages 3.7 cm/year. This rate is not stable and it generally shows a parallelism in the fluctuations perennially. The measurements conducted in Tatvan show that this rise approximated to 2 meters (2.1 m) in 1944–2000. The swift rise, especially after 1987, has caused an environmental disaster in the coasts, inundating approximately 5200 hectares of land. Tens of villages together with Van, Tatvan, Ercis, Adilcevaz and Ahlat cities were affected, and thousands of houses, tens of thousands of acres of agricultural lands, highways, ferry harbour, historical sites, and wetlands in the mouths of streams, shelters of wild birds were damaged. In addition to all these, drinking waters, canalization network, urban infrastructure systems as well as some parts of Van Airport and many camping areas of holiday were reported to have been damaged due to the same reasons. In this investigation we aimed to determine the environmental consequences of level changes and the measures to be taken accordingly.  相似文献   

Determination of near-fault impulsive signals with multivariate naïve Bayes method     

Ertuncay  Deniz  Costa  Giovanni 《Natural Hazards》2021,108(2):1763-1780

Natural Hazards - Near-fault ground motions may contain impulse behavior on velocity records. To calculate the probability of occurrence of the impulsive signals, a large dataset is collected from...  相似文献   

A LabVIEW-based fire monitoring software using multi-criteria AHP approach for detecting geolocation of wildfire     

Gulluce  Yucel 《Natural Hazards》2021,109(2):1849-1876

Natural Hazards - High Conservation Value Forests or botanical parks are critical forested areas that need to be appropriately managed and protected against fire, as they contain large...  相似文献   

Extreme temperatures linked to the atmospheric blocking events in Turkey between 1977 and 2016     

Efe  Bahtiyar  Lupo  Anthony R.  Deniz  Ali 《Natural Hazards》2020,104(2):1879-1898

Natural Hazards - Extreme maximum (Tx) and extreme minimum temperature (Tn) frequency distributions during summer and winter for blocked conditions were analyzed within Turkey during the period...  相似文献   

Northern Barbados accretionary prism: Structure,deformation, and fluid flow interpreted from 3D seismic and well‐log data     

Deniz Cukur  Gwang H. Lee  Jeong G. Um  Dae C. Kim  Jin H. Kim 《Island Arc》2009,18(4):642-660

We reanalyzed 3D seismic reflection and logging‐while‐drilling data from the toe of the northern Barbados accretionary prism to interpret structure, deformation, and fluid flow related to subduction processes. The seafloor amplitude and coherence reveal an abrupt change in the thrust orientation from NNE at the thrust front and north and NNW about 5 km west of the thrust front. These thrust sets are separated by a triangular‐shaped quiet area, which may represent a zone of low strength. The northeast‐trending band of strong negative amplitude and high coherence in the décollement, known to be an interval of arrested consolidation, overlaps the quiet area, suggesting that the arrested consolidation may be related to the lack of thrust imbrication, and thus, vertical drainage for fluid in the accretionary prism. Fractal analysis of the décollement and top of the subducting oceanic basement indicates that the relief of the décollement correlates with the topography of the oceanic basement. Differential compaction of the underthrust sediment overlying the rugged oceanic basement, together with the basement faults that penetrate into the décollement probably caused relief or even faulting in the décollement.  相似文献