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21.
Cem Tokatli Arzu Çiçek Özgür Emiroğlu Naime Arslan Esengül Köse Hayri Dayioğlu 《Environmental Earth Sciences》2014,71(5):2185-2197
Emet Stream is one of the most important branches of Uluabat Lake (Ramsar area) and also one of Turkey’s most important river systems. In addition to the geologic structure of the basin, Harmancik Chromium Mines are one of the most important inorganic pollution sources for the basin and also for Uluabat Lake. In the present study, water, sediment and fish (Squalius cii, Capoeta tinca and Barbus oligolepis) samples were collected seasonally from eight stations (one of them was on the Kinik Stream where the Harmancik Chromium Mines is located on and one of them was on the Dursunbey Stream) on the Emet Stream Basin. Some limnological parameters (pH, conductivity and total hardness) in water and Cr, Ca, Mg, Ni and Mn levels in biotic (muscle, gill, liver and kidney tissues of fishes) and abiotic (water and sediment) components of basin were determined to evaluate the effects of Harmancik Chromium Mines on the system. Cluster Analysis, Factor Analysis, Pearson Correlation Index, One Way Anova Tests, Scatter dot Comparing and Matrix plot Distribution Diagrams were applied to the results in order to estimate the data properly. Water samples were evaluated according to the water quality criteria for Turkey and sediment samples were evaluated according to the sediment quality criteria. According to data obtained, statistically significance differences were identified between Kinik and Emet Streams according to Cr and Ni accumulations in water and sediment. Chromium levels of Kinik Stream were extremely higher an average of 153 times for water and 10 times for sediment than uncontaminated stations. Water and sediment quality of Emet Stream were decreasing after falling the Kinik Stream and increasing after falling the Dursunbey Stream. It was also determined that, the amount of chromium in muscle tissues of three fish species were much higher than the limit value of 0.15 mg kg?1 that FAO identified. 相似文献
22.
Landslide susceptibility assessment in the İzmir (West Anatolia,Turkey) city center and its near vicinity by the logistic regression method 总被引：1，自引：1，他引：0
A landslide susceptibility assessment for İzmir city (Western Turkey), which is the third biggest city of Turkey, was performed
by a logistic regression method. A database of landslide characteristics was prepared using detailed field surveys. The major
landslides in the study area are generally observed in the field, dominated by weathered volcanics, and 39.63% of the total
landslide area is in this unit. The parameters of lithology, slope gradient, slope aspect, distance to drainage, distance
to roads and distance to fault lines were used as variables in the logistic regression analysis. The effect of each parameter
on landslide occurrence was assessed from the corresponding coefficients that appear in the logistic regression function.
On the basis of the obtained coefficients, lithology plays the most important role in determining landslide occurrence and
distribution. Slope gradient has a more significant effect than the other geomorphological parameters, such as slope aspect
and distance to drainage. Using a predicted map of probability, the study area was classified into five categories of landslide
susceptibility: very low, low, moderate, high and very high. Whereas 49.65% of the total study area has very low susceptibility,
very high susceptibility zones make up 11.69% of the area. 相似文献
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24.
A solid waste disposal site selection procedure based on groundwater vulnerability mapping 总被引：2，自引：0，他引：2
In this study, a new, GIS-based solid waste site selection tool (DUPIT) is introduced to obtain a systematic and unbiased
methodology during the evaluation phases of alternative solid waste disposal areas with regards to vulnerability to groundwater
pollution. The proposed tool is an index technique based on the linear combination of five different hydrogeological parameters
including Depth to groundwater table, Upper layer lithology, Permeability of the unsaturated zone, Impermeable layer thickness and Topographic slope. Five different categories are developed to classify each alternative based on the suitability of the site
for a solid waste disposal area. As a result, each site is ranked according to the contamination risks for groundwater resources.
The proposed technique is applied to the District of Torbali near Izmir, Turkey to determine the most appropriate solid waste
disposal site location. The Torbali application is implemented by using a GIS database developed for the area. Based on the
results of this application, the best alternative solid waste disposal site for Torbali is selected to be located in the northern
portions of the city where the groundwater table is deep, the permeability is low and the topographic slope is mild. 相似文献
25.
S?cak Çermik (Sivas) is an important geothermal and recent travertine formation area in Central Anatolia. The majority of travertines found in the region comprise fissure-ridge type travertines according to morphological classification. At the location called Tepe Çermik within the travertine area, fill containing fossil bone fragments of Equus sp., Bovidae and other abundant animals formed within the fracture axis of a N–S striking fissure-ridge travertine developed under control of tectonic forces. The finds of these fossils in fissure-ridge travertines linked to tectonic forces indicates formation of a unique fossil environment created under the control of these forces. The Accelerator Mass Spectrometry Radiocarbon Dating analyses of fossils from the study area determined the fills were older than 43,000 years. The U/Th age of a sample from the most recently-formed banded travertine in the axis of the fracture was identified as 278,540 ± 18,436 years. As a result, the ages of fossils found within this fill are thought to be between 43,000 and 278,540 ± 18,436 years old. The high amount of perissodactyla and artiodactyla fossils found within fill in the axis of the fissure-ridge travertine probably indicates the presence of hominids who chose the region for hunting or settlement. The Equus sp. and Bovidae fossil samples found in the axis of the fracture indicate that in the dry and cold glacial period the paleogeography in a large portion of Anatolia comprised desert-like steppe. 相似文献
26.
An empirical attenuation relationship for Northwestern Turkey ground motion using a random effects approach 总被引：2，自引：0，他引：2
Cem
zbey Ali Sari Lance Manuel Mustafa Erdik Yasin Fahjan 《Soil Dynamics and Earthquake Engineering》2004,24(2):115-125
Using a random effects model that takes into consideration the correlation of data recorded by a single seismic event, a database consisting of 195 recordings from 17 recent events is employed to develop empirical attenuation relationships for the geometric mean of horizontal peak ground acceleration and 5-percent damped spectral acceleration (Sa). The recordings employed are obtained from strong motion stations operating in Northwestern Turkey and resulted from events that include the Kocaeli (Mw=7.4) and the Düzce (Mw=7.1) earthquakes and their aftershocks as well as other events. By studying differences in standard errors, the random effects model is compared with a fixed effects model that does not account for distinctions between intra- and inter-event variability. Effects of local site conditions are included in the empirical relationships developed. The dependence on frequency of the various model parameters is also studied. Frequency-dependent attenuation coefficients for the proposed random effects models developed are summarized in tables to facilitate their use. 相似文献
27.
A. Cem Koc 《Journal of Earth System Science》2008,117(1):59-67
Karstic aquifers significantly contribute to streams in most of Turkey’s river basins, so studies on karst water resources
have great importance for Turkey. Karstic aquifer contributions are generally emerging at several locations near the river
bed and are not readily measured by direct hydrometric methods. In this study, the extent of karstic aquifer contributions
to a stream will be investigated by the statistical analysis of recession coefficients of recession curves. Six stream gauging
stations on different streams in the western Mediterranean region of Turkey are selected. Recession periods of the streams
are simulated by exponential and quadratic recession curve models. Recession coefficient series of the stream gauging stations
are statistically investigated. The comparison of various statistical parameters shows that the recession coefficient series
are fairly related to the karstic aquifer contributions. Especially, the measure of spread parameters, standard deviation
and interquartile range of recession coefficient series are related to the extent of the karstic aquifer contributions to
streams. 相似文献
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29.
A new analysis technique has been proposed for interpreting transient step-drawdown test data. The proposed method is based on taking the derivative of the drawdown with respect to time for the entire pumping test period to eliminate the time-independent well-loss terms. The derivative function is subsequently integrated to obtain the time-dependent aquifer drawdown as a continuous function. The well-loss parameters are then obtained with higher accuracy once the aquifer behavior is identified. The proposed method is applicable for analyzing data obtained not only from ideal confined aquifers but also from other aquifer types (i.e. unconfined) and non-ideal aquifers (i.e. heterogeneous). The technique was tested for synthetically generated and field data; the proposed approach was noted to provide accurate aquifer and well-loss parameter estimates. The results of the proposed method were compared with those of some of the existing methods for analyzing step-drawdown test data and were found to be more reliable and robust. 相似文献
30.
Purification of diatomite powder by acid leaching for use in fabrication of porous ceramics 总被引：1，自引：0，他引：1
This study presents an investigation of the purification of a raw diatomite by acid leaching conducted in hot solution (75 °C and 5 M HCl) for long periods up to 240 h, evaluates the use of these purified powders in the fabrication of porous materials, and examines their porosities. The treatment for 1 h increased the specific surface area of diatomite from 189 m2/g to 222 m2/g, but the SiO2 content of 78.66% was still low. Material leached for a relatively short time shows an amorphous phase with quartz and plagioclase phases and the plagioclase is removable at longer leaching times during which no disruptive effect on the fine microscopic pores of the particles was observed. Thus, the diatomite based powders have potential use in the fabrication of porous coating as a membrane-separating layer: sintering at a relatively high temperature (1300 °C) still showed a significantly high apparent porosity of 48%. 相似文献