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Tekeli-Yeşil Sıdıka Dedeoğlu Necati Braun-Fahrlaender Charlotte Tanner Marcel 《Natural Hazards》2011,59(1):427-446
Awareness and perception of risk are among the most crucial steps in the process of taking precautions at individual level
for various hazards. In this study, we investigated the factors affecting better knowledge and greater risk perception about
earthquakes among residents of Istanbul. A field survey was carried out, and a total of 1,123 people were interviewed in two
districts of Istanbul with different seismic risk levels and from three (low, moderate and high) socio-economic levels (SEL).
The findings showed that although the level of knowledge regarding earthquakes and preparedness for them was promising, it
could be improved. The results indicated that future preparedness programmes should target people with lower educational and
socio-economic levels. The media were the leading source of information among the respondents. Location of the home was a
strong influence on individuals having above average earthquake knowledge and even more on high risk perception. Socio-economic
parameters (educational level, economic status, SEL of the sub-district and tenure of the home), gender and attitude score
were other factors influencing greater risk perception with regard to earthquakes. 相似文献
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This paper presents the results of morphotectonic and morphometric research carried out in order to determine the neotectonic development of the volcanic mountains and a drainage network in SW Cappadocia. The study area extends among the Aksaray, Ni?de, and Nev?ehir Provinces. The study area comprises Hasanda?, Melendiz, Keçiboyduran, Göllüda? Mountains and the adjacent parts of these volcanic mountains.Data collected exclusively from 1:25,000 digitised topographic maps and 10 m-resolution DEMs were used to define parameters related to the longitudinal profile of streams. The study area was divided into 10 volcanic units. Longitudinal profiles of 20 streams and stream orders were analysed to determine a regional tectonic differentiation pattern in these units. The streams in the study area drain into four different tectonic depressions. These depressions are Aksaray plain controlled by the Tuz Gölü fault (TGF), Çiftlik plain controlled by the Keçiboyduran–Melendiz fault (KMF), Misli plain controlled by the Derinkuyu fault (DF), and Bor plain controlled by the Ni?de Fault Zone (NFZ). An analysis of morphometric parameters shows that the development of a drainage network is associated with faults and rock resistance. Occurrence of morphometric parameters with different values in units reveals that the volcanic mountains were not uplifted in the same period and were subjected to different morphologic processes. High total order number in the south of Hasanda? (unit 3) and Melendiz Mountains (unit 7) indicate that the uplift ratio of the southern part is much greater than that of the northern part. Moreover, development of the drainage network in the south is in a more advanced phase than in the north. Indeed, the drainage network in the north is in the youngest erosional phase of all parts of the study area. The increased stream length-gradient indices (SL), and stream gradients and an analysis of headward erosion show that the streams displaying the longest and highest reach of the erosional phase are all in the southern part of Keçiboyduran and Melendiz Mountains. The longitudinal profile (Lp) of the present thalweg of the streams is irregular. The irregular Lp are associated with four different causes. These are geological variations in resistance, tectonics, and volcanic topography and downcutting in response to stream incision. The beginning of the fluvial incision in the northern part is younger than in the south. 相似文献
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Water pollution is a widespread problem in different areas of the world. Some of these problems originated from point contamination sources and widespread contaminant outlet sources which are observed in every country. The major elements and chemical loads of surface water have been dominated by constituents derived directly or indirectly from human activities and/or industrial practices that have increased additives in the last several decades. The point sources of contamination may result from the direct wastewater discharges to the dam sites, which are considered to be the most commonly encountered water pollution problems. One of these problems is the eutrophication process which usually occurs in the static water mass of lakes and other surface water reservoirs. This process may be caused by the continuous increase of nitrogen and phosphorus contents and decrease of O2 level in water causing an anaerobic condition which may stimulate algae-growth flow in these water bodies, consequently reducing the quality of water. Of course, there are many research methods for determining the various kinds of water pollution. In this research, the hydrochemical parameters were evaluated to estimate the types of pollution sources, the level of pollution, and its environmental impacts on the Tahtal dam reservoir. 相似文献
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This study investigates divering overland flow utilizing kinematic wave theory, which does not appear to have been dealt with previously. Explicit analytical solutions are derived in dimensionless form for space-time invariant rainfall. Analytical solutions do not seem to be tractable for time-varying rainfall. Depending upon the duration of rainfall, equilibrium and partial equilibrium cases are distinguished explicitly. The effect of divergence parameter on the hydrograph shape is shown. The adequacy of kinematic approximation for characterization of diverging overland flow is tested against laboratory watershed results. The diverging overland flow model is found to yield results which compare well with observations and with those of a plane model. 相似文献
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The United Kingdom Institute of Hydrology (UKIH) smoothed minima baseflow separation method originally developed for the daily flow data of perennial streams and adopted for intermittent streams is presented. The adopted method (AdUKIH) is the generalized version of the UKIH and hence applicable not only to intermittent streams but also to perennial streams. The AdUKIH method is applied on three daily streamflow gauging stations from the European part of Turkey, the Thrace region. The AdUKIH enables one to change the parameter 0·9 in the UKIH method and also introduces different block sizes, which is limited to five days in the original UKIH method. The AdUKIH method is considered a useful tool in helping practitioners and researchers to separate continuous baseflow from the daily flow in perennial and intermittent streams. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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The amount of sediment should be taken into consideration in the planning of water structures for efficient use of limited water resources. It is important to estimate the amount of sediment for the successful operation of these structures in their future performances. Such estimations can be achieved by Artificial Neural Network (ANNs) with low error percentages as seen in many other disciplines. These networks also enable the modeling of nonlinear relationships between the parameters affecting the event. The purpose of this research is to establish models for sediment amounts in the Tigris River at the Diyarbakir measurement station in Turkey. Rainfall, temperature and discharge are taken as independent variables in the models, whereas sediment is taken as the dependent variable. Fourteen different models are generated using ANNs and Regression Analysis (RA). The results are compared with each other and with the observed data. The relative error and determination coefficient are used as comparison criteria. It is concluded that due to their nonlinear modeling capability, ANNs give better results than RA. 相似文献
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Mainly high-K, calc-alkaline, Late Miocene to Pliocene volcanic rocks cropped out of the Konya area in Central Anatolia, Turkey. The volcanic rocks are predominantly andesitic to dacitic in composition and rarely basalt, basaltic andesite, basaltic trachyandesite and pyroclastics. Kaolinite, illite, Ca-montmorillonite, alunite, jarosite, minamiite and silica polymorphs were formed by widespread and intense hydrothermal alteration in or around the volcanic products. To investigate the effects of hydrothermal alteration on the chemistry of volcanic rocks, the whole rock chemical composition (major and trace elements, including rare-earth elements (REE) was analysed. The results of the study demonstrate notable differences in the REE behaviour in the different sample groups. REE trends of fresh parent rocks to weakly-, moderately-altered, kaolinitic and alunitic rocks are characterised by strong LREE enrichment ((La/Lu)cn = 14.57, 11,8 to 15.20, 4.54 to 13.30, 12.5 to 24.2 and 34.6 to 47.26, respectively). Most of the samples have pronounced negative and/or weakly-negative Eu anomalies ranging from 0.75 to 0.98 while three samples have weakly-positive Eu anomalies. LRE element contents are higher than those of HREE in the samples. The LRE elements were strongly enriched in the kaolinitic and alunitic alteration; in weakly- and moderately-altered rocks. LREE are nearly immobile whereas HRE elements show different behaviour in different rock groups. The HFS and TRT elements are slightly mobilised in weakly-altered rocks, but enriched in other alteration types. Elements commonly assumed to be immobile (e.g. Y, Zr, Nb, Hf, TiO2, Al2O3, REE) show variation in mass calculation. LIL elements showed enrichment over LREE and MREE, and similar behaviour, in contrast with HFSE. A clear increment of trans-transition elements (TRTE) was found mainly in alunitic and partly in kaolinitic samples. 相似文献
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The study area is situated in a large agricultural field which produces tobacco, maize, and other yearly cultivated vegetables in Tekkeköy, Samsun (NE-Turkey). In addition, a significant part of this area to the north along the Black Sea coast is occupied by several industrial plants such as a copper smelting plant (KB?), a fertilizer plant (Tügsa?) and industrial park facilities (IPF). In order to reveal their environmental impacts, heavy metal analyses were conducted on soil, plant leaves and water samples collected within an area of approximately 30 km2 around these plants. Soil samples within an area of 10 km2 around these facilities are found to be highly polluted with Cu, Zn, Pb, Fe and Mn. Pollution occurs at surface and sharply dies out at 20 cm downwards in soil profile. Since the region is polluted mostly with base metals, the copper smelting factory appears to be the main source of pollution as it processes the massive sulfidic ores of the Black Sea area. Plants show Cu, Pb, Zn and Fe pollution around KB? and Tügsa? and Cu and Pb around IPF. Pollutants observed in tobacco (Nicotiana tobacum) are Cu, Pb, Zn, Fe and S; in maize (Zea mays) Cu, Zn and Fe; and in cabbage (Brassica oleracea) Cu, Pb, Fe and S. The analyses of water samples collected from the study area reveal that Pb and, to a lesser degree, Cu and Fe pollution stem from KB?; Cu, Fe and Mn pollution from Tügsa?; Pb and minor amounts of Fe and Mn pollution from IPF. Factor analyses from analyzed metals and anionic complexes in water show three distinct groups: (a) an association of heavy metals with Na, K and Mg referring to pollution and acid leaching of soil, (b) an association of NH4, Fe, SO4, Cl and Br indicating agricultural pollution and sea-water invasion in land near the shore line, and (c) HCO3 behaving in a different manner in heavy metal precipitation. 相似文献
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The effects of coastline, together with the other geographical and topographical factors such as longitude, latitude, elevation and distance from sea, on mean annual precipitation are investigated for the coastal area of the eastern Black Sea region. In this location, mountains run parallel to the sea coast. The coastline configuration is represented by a new variable, the coastline angle. A multiple linear regression (MLR) analysis is performed on mean annual precipitation recorded in coastal and inland gauges. In the study area, three variables—longitude, latitude and coastline angle—can explain 81% of the spatial variability of precipitation for the coastal gauges and 93% of that for the inland gauges. When the entire study area considered, without grouping the gauges, 80% of the spatial variability is explained by these variables. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献