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Deniz Arca Hulya Keskin Citiroglu Hakan S. Kutoglu Cetin Mekik Tomonori Deguchi 《Natural Hazards》2017,87(1):307-322
Kozlu is a mining town only 5 km away from the main city of Zonguldak and initially was not favored for settlement due to its rugged and hilly topography. However, along with hard coal production in large quantities throughout the years came the industrialization at its full speed with plenty job opportunities which then gave rise to intense population in the region where there were only a few sheds and slums just a century ago. Workers migrating to Kozlu in thousands needed dwellings to live in, but the law, so-called the Coal Basin Restrictions Law which came in effect in 1910, hindered the implementation of zoning plans. Planned housing was not possible in the region not until the abolishment of the law in 1986. During these 76 years, the settlement in the area mostly by the mining and industry workers was carried out without proper zoning plans, usually on demand basis. Today because of this unplanned housing and harsh topography, the Kozlu settlement area (KSA) has a history of being attraction point for many natural and man-made disasters which can be summarized as are topography, geological and carstic structure, mining activities and mass movements. In this study, a settlement suitability map is produced for the study area using a geographic information system. The map produced is designated into four settlement suitability zones, namely suitable to settlement, slightly suitable to settlement, suitable to settlement with precautions and unsuitable to settlement. It clearly shows that 24.73% of the study area lies in suitable and slightly suitable to settlement areas while the bulky rest pertains to suitable to settlement with precautions and unsuitable to settlement. The latest studies show that the 37.5% of the buildings and houses in the KSA are situated on the lithologic units identified as hydrogeological permeable and semipermeable, 7.8% on carstic caverns and a hefty rate of 47.6% on the surfaces deformed by mining-induced subsidence. Therefore, it is needless to claim that the administrators of Kozlu should promptly develop a settlement plan for the welfare of the city. 相似文献
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Huseyin Ozdemir Bulent Mertoglu Goksel Demir Ali Deniz Hüseyin Toros 《Theoretical and Applied Climatology》2012,108(3-4):553-562
In a world where at least 50% of the population is living in urban environments, air pollution and specifically particulate matter (PM) have become one of the most critical issues for human health. Children are more susceptible than adults to air pollution and its adverse effects because they inhale and retain larger amounts of air pollutants per unit of body weight. In this study, PM pollution, particularly PM10 and PM2.5, at selected playgrounds were investigated in Istanbul city. Istanbul is a megacity of over 15 million inhabitants, and on-road traffic is increasing rapidly (over 3 million vehicles on the road). To estimate the effect of traffic emissions on children, the location of the playgrounds were selected according to traffic density. Measurements were carried out at five different playgrounds throughout the city in 2009. Field results show that the values of PM10 and PM2.5 have reached critical limits at the playgrounds close to the main roads, especially at P-1. Thus, we focused on this location and investigated a source other than traffic emissions. One of the episode days has been observed on 5–7 March 2009. Evaluations of meteorological events are very important to determine air pollution sources and their long-range transport. Therefore, the Weather Research and Forecasting model (WRF) was used to simulate and forecast meteorological parameters and the hybrid single-particle Lagrangian integrated trajectory (HYSPLIT) applied to investigate long-range transport. According to the WRF model outputs, there was a low-pressure system over Geneva gulf on the 500-hPa level, and its core had been located over Britain on 5 March 2009 00UTC. The system had been sweeping dust from the Sahara Desert and carrying the air particles over Istanbul. Similarly, backward HYSPLIT analysis showed that air particles had moved through Istanbul from Northern Africa. 相似文献
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Magnitude conversion problem for the Turkish earthquake data 总被引：1，自引：0，他引：1
Earthquake catalogues which form the main input in seismic hazard analysis generally report earthquake magnitudes in different
scales. Magnitudes reported in different scales have to be converted to a common scale while compiling a seismic data base
to be utilized in seismic hazard analysis. This study aims at developing empirical relationships to convert earthquake magnitudes
reported in different scales, namely, surface wave magnitude, M
S, local magnitude, M
L, body wave magnitude, m
b and duration magnitude, M
d, to the moment magnitude (M
w). For this purpose, an earthquake data catalogue is compiled from domestic and international data bases for the earthquakes
occurred in Turkey. The earthquake reporting differences of various data sources are assessed. Conversion relationships are
established between the same earthquake magnitude scale of different data sources and different earthquake magnitude scales.
Appropriate statistical methods are employed iteratively, considering the random errors both in the independent and dependent
variables. The results are found to be sensitive to the choice of the analysis methods. 相似文献
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This study aimed to reveal the temporal statistics, formation mechanisms, suitable land/sea surface (LS/SS) and upper-level atmospheric conditions, and predictability of thundersnow (TSSN) events that occurred between 2000 and 2021 in the Marmara Region with atmospheric stability indexes. Aviation reports from 11 airports were analyzed throughout the period, and no TSSN events were found at four airports. A total of 19 TSSN events were identified, and six events were found in 2015, when the sea-effect snow (SES) mechanisms were observed four times. The majority of TSSN events were of very short duration (0–1 h), and no significant trend was observed in terms of intraday distribution. SES mechanism was observed in 17 of the 19 TSSN events, and the dominance of northern flows was detected at all airports and at the sub-inversion upstream levels. In terms of air-sea interaction, suitable temperature differences between the SS and 850/700 hPa (17 °C and 27 °C on average), and the transfer of heat-moisture fluxes from the SS to the upper-atmosphere were possible in almost all TSSN events. In this way, meteorological parameters were sufficient for the formation and strengthening of the convective layer. In addition, the presence of directional wind shear and the observation of inversion layers restricting convective movements at higher levels instead of near the surface ensured that the moisture requirement, lifting mechanism, and unstable atmospheric conditions required for the formation of TS were provided. The CAPE values were very low for winter TSs. Total Total Index and TQ Index produced the most appropriate results for TSSN prediction.
相似文献57.
Gullu Deniz Dogan-Kulahci Abidin Temel Alain Gourgaud 《Chemie der Erde / Geochemistry》2018,78(1):103-115
The Cemilköy ignimbrite is one of the voluminous ignimbrite deposits in Cappadocia. The Cemilköy ignimbrite contains pumice and lithic clasts of volcanic and ophiolitic origin in an ash matrix. The unwelded Cemilköy ignimbrite is distinguished from other deposits in Cappadocia by flattened pumices, elongate vesicles and a slaty fabric. The mineral assemblage of the Cemilköy ignimbrite is plagioclase, biotite, quartz and oxides (magnetite and Ti-magnetite) and the matrix is glassy. Eutaxitic texture is dominant and all pumice clasts have a vitrophyric-porphyritic texture. The same textural properties were observed throughout the spatial distribution of Cemilköy ignimbrite. Microprobe studies reveal that plagioclase compositions range from albite through oligoclase-andesine. Estimated plagioclase-liquid temperatures (T) and pressures (P) are varying between 806 and 847?°C and 4.2–7.1 (kbar), and the H2O content of the melt is estimated to have been 5?wt.% from the pumice clasts. Based on geochemical data, the Cemilköy ignimbrite is rhyolitic and calc-alkaline in character, and all pumice clasts are enriched in LIL and LRE elements relative to HFS elements. Negative Nb, Ta and Ti anomalies, ratios of Ba/Nb >28 (56–77), Ba/Ta ?450 (590–700) and Th/Yb vs. Ta/Yb are consistent with a subduction-related origin. According to the geochemical and mineralogical-petrographical data, the Cemilköy ignimbrite originated from partial melting of a mantle source which was enriched during previous subduction processes with variable degrees of assimilation fractional crystallization (AFC) through time and Cemilköy ignimbrite erupted from a crustal magma chamber at shallow to intermediate depth. 相似文献
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Neşer G Kontas A Unsalan D Altay O Darılmaz E Uluturhan E Küçüksezgin F Tekoğul N Yercan F 《Marine pollution bulletin》2012,64(5):1055-1059
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. Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons in sediment of the Alia?a Bay were investigated to evaluate an environmental risk assessment from PAHs contamination in 2009-2010. Aliphatic and PAHs diagnostic ratios were showed to be mainly petroleum-originated and pyrolitic contaminations, respectively. The TEL/PEL analysis suggests that Alia?a sediments were likely to be contaminated by acutely toxic PAH compounds. 相似文献
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Grant W. Tempero Brendan J. Hicks Nicholas Ling Dai Morgan Adam J. Daniel Deniz Özkundakci 《新西兰海洋与淡水研究杂志》2019,53(3):397-415
Introduced common carp (Cyprinus carpio) are a recognised threat to New Zealand’s freshwater ecosystems. In 2011, an invasive fish removal programme was undertaken in 16.8 ha Lake Ohinewai, a Waikato riverine lake. Active fish removal using netting and boat electrofishing was supported by installation of a one-way exclusion barrier on the outflow to Lake Ohinewai. The barrier was designed to allow fish passage downstream out of the lake, while preventing adult carp from moving upstream. The estimated carp population was reduced from 8,548 fish (5,863–12,937, 95% confidence limits) in 2011–454 fish (251–889, 95% CL) in 2014. However, by 2016 the carp population had recovered to 2,063 fish (1,070–4,328, 95% CL) with increased abundance in invasive brown bullhead catfish (Ameiurus nebulosus) also observed. This research demonstrates that carp populations can be reduced to low abundances in the short to medium term, but continued removal will be required for on-going control. 相似文献