Comparison of response of moss,lichens and attic dust to geology and atmospheric pollution from copper mine     

B. Balabanova  T. Stafilov  R. Šajn  K. Bačeva 《International Journal of Environmental Science and Technology》2014,11(2):517-528

Different sampling media (moss, lichen and attic dust) were used for monitoring the distribution of 15 elements, including certain trace elements, in the vicinity of an intensively exploited copper mine in the east of the Republic of Macedonia. Moss species (Hypnum cupressiforme and Campothecium lutescens), epiphytic lichens (Hypogymnia physodes and Evernia prunastri) and attic dust were collected for comparative analysis for monitoring air pollution. In both cases (lithological and anthropogenic affected areas) for the distribution of elements, the sampling media follows the expression capabilities: attic dust > moss > lichens. Enrichment factors M/L—moss vs. lichen, for plant response to elements distribution and D/L—attic dust vs. lichen, for historical response of elements distribution were significant for Cu and Ni, which were singled out as the main markers for anthropogenic and geogenic distribution. The factor analysis highlighted geogenic (F1: Ni-Cr-Cd-Fe-Al-K-Mn-Zn) and anthropogenic (F2: As-Cu-Pb) association of elements from three types of media samples. For anthropogenic affected areas, T value and F value for Cu content were significant at p < 0.05 and higher enrichment factors were obtained for lichen, moss and attic dust media (3.8, 5.0 and 5.7, respectively). Spatial distribution for element deposition (with emphasis on Cu and Ni) is not disturbed by the significant differences in the sampling media matrix. Treated sample materials (attic dust, moss, lichen) are shown to be useful in determining an anthropogenic impact, as well as the chemical properties or geological background on orographic diverse terrain in the presence of complex geological structure.  相似文献   

Investigation of surface and subsurface displacements due to multiple tunnels excavation in urban area     

Alireza Talebinejad  Hamid Chakeri  Mahdi Moosavi  Yılmaz Özçelik  Bahtiyar Ünver  Mehmet Ali Hindistan 《Arabian Journal of Geosciences》2014,7(9):3913-3923

Underground structures are currently widely used and are built as urbanism develops. The interactions between perpendicularly crossing and parallel tunnels in the Tehran region are investigated by using a full three-dimensional (3D) finite difference analysis with elastic-plastic material models. Special attention is paid to the effect of subsequent tunneling on the support system, i.e., the shotcrete lining and rock bolts of the existing tunnel. Eventually, as the tunnels are excavated at certain levels, the interaction between the tunnels will certainly have a significant influence on both stress distribution and consequently deformations. Since multilayer tunneling is a three-dimensional phenomenon in nature, 3D numerical solutions must be utilized for analyzing effect of perpendicularly crossing tunnels at various levels. As Tohid twin tunnels and Line 7 pass beneath the Line 4 metro tunnel, changes in stress distribution, deformations, and surface settlements are studied for various conditions and the results are presented in this paper. Consequently, it is shown that there is a significant interaction between tunnels that necessitate certain preventive measures to maintain a stable tunneling operation.  相似文献   

Responses of microorganisms and enzymes to soil contamination with metazachlor     

Ma?gorzata?Ba?magaEmail author  Jan?Kucharski  Jadwiga?Wyszkowska  Agata?Borowik  Monika?Tomkiel 《Environmental Earth Sciences》2014,72(7):2251-2262

A greenhouse pot experiment was conducted at the University of Warmia and Mazury in Olsztyn, with the aim of describing the influence of metazachlor on counts and biodiversity of soil microorganisms, soil enzymatic activity, physicochemical properties of soil and yield of spring oilseed rape. The first experimental factor was soil contamination with increasing rates of metazachlor: 0 (soil without the herbicide), 0.333 (recommended by the manufacturer), 6.666, 13.332, 26.665, 53.328, 106.656 and 213.312 mg kg^?1 dm of soil, while the second factor comprised two dates of determination: 30 and 60 days after starting the experiment. The tested herbicide had an adverse effect on reproduction of all analyzed microorganisms: oligotrophic bacteria and their endospore forms, Azotobacter spp. bacteria, organotrophic bacteria, actinomycetes and fungi. The values of the colony development and eco-physiological diversity indices decreased under the influence of excessive doses of the herbicide. Also, significant fluctuation in the enzymatic activity of soil was observed in response to the higher doses of metazachlor and depending on the date of determinations. The herbicide had an invariably negative influence on the activity of soil enzymes, causing the inhibition of dehydrogenases, catalase, urease, acid phosphatase, alkaline phosphatase, arylsulfatase and β-glucosidase. The physicochemical status of soil depended significantly on the degree of soil contamination with the herbicide, same as the yield of spring oilseed rape.  相似文献   

Designing a flood forecasting and inundation-mapping system integrated with spatial data infrastructures for Turkey     

Halil Akıncı  Sevsin Erdoğan 《Natural Hazards》2014,71(1):895-911

Turkey currently lacks a fully functional flood forecasting system (FFS). However, the studies necessary for establishing such a system are still being performed by the Turkish State Meteorological Service. The main purpose of this study was to determine the technical architecture of the FFS intended to be developed in Turkey and to design a flood forecasting and inundation-mapping system integrated with spatial data infrastructure (SDI). Because SDIs provide interoperability among the institutions by enabling collective use of data and services, this enables decision makers to take correct and rapid decisions regarding the forecasting. In the design of the system, the Web services architecture presented by the open geospatial consortium that develops international standards for SDI realizations was taken as a basis. Designed with flexibility and an expandable architecture, the system will enable instant access to up-to-date data from different institutions through Web services and meets the requirements of a real-time FFS. While the criteria requiring the expansion of the designed system were explained, its implementation was left for future studies.  相似文献   

Volcanic facies and mineral chemistry of Tertiary volcanics in the northern part of the Eastern Pontides,northeast Turkey: implications for pre-eruptive crystallization conditions and magma chamber processes     

Cem Yücel  Mehmet Arslan  İrfan Temizel  Emel Abdioğlu 《Mineralogy and Petrology》2014,108(3):439-467

Tertiary volcanics in the northern zone of the Eastern Pontides are characterized by subaerial and shallow-subaqueous facieses, and are divided into three volcanic suites: Eocene aged (1) basalt-trachybasalt-basaltic trachyandesite (BTB) and (2) trachyte-trachyandesite (TT), and Miocene aged (3) basanite-tephrite (BT) suites. Clinopyroxene is a common phase in all three volcanic suites, and has different compositions with Mg# varying from 0.57 to 0.91 in BTB suite and 0.57–0.84 in TT suite to 0.65–0.90 in BT suite. Feldspars in all suites generally exhibit wide range of compositions from sanidine to albite or anorthite and have weak normal and reverse compositional zoning. Olivines in BTB and BT suites have Fo_60–92. Hornblendes in BTB, TT and BT suites are commonly magnesio-hastingsite and rare pargasite in composition (Mg#: 0.67–0.90). Brown mica is mainly phlogopite with Mg# ranging from 0.56 to 0.92 in the BTB suite, 0.59–0.84 in the TT suite, and 0.75–0.93 in the BT suite. Analcime is present only in the BT suite rocks. Fe–Ti oxides in all suites are mainly composed of magnetite and titanomagnetite. Textural petrographic and mineral chemical data suggest that magmas had undergone hydrous and anhydrous crystallizations in deep-, mid-, and shallow-crustal magma chambers. Clinopyroxene thermobarometric calculations show that Eocene magma chambers were characterized by temperature ranging from 1,100 to 1,244 °C and pressure ranging from 1.84 to 5.39 kbar. Similarly, the Miocene magma chambers were characterized by temperature ranging from 1,119 to 1,146 °C and pressure ranging from 4.23 to 4.93 kbar. Hornblende thermobarometry, oxygen fugacity, and hygrometer reveal that the crystallization temperature of Eocene volcanics range from 956 to 959 °C at pressure ranging from 6.49 to 6.52 kbar. Eocene volcanics were characterized by water content ranging from 7.83 to 8.57 wt.% and oxygen fugacity of 10^?9.36 to 10^?9.46 (ΔNNO+2). Miocene volcanics had crystallization temperature ranging from 970 to 978 °C at pressure ranging from 8.70 to 9.00 kbar with water content ranging from 8.04 to 8.64 wt.% and oxygen fugacity ranging from 10^?8.75 to 10^?8.87 (ΔNNO+2). Brown mica thermobarometric data show that Eocene volcanics were characterized by relatively high oxygen fugacity varying from 10^-10.32 to 10^-12.37 (HM) at temperature ranging from 858 to 953 °C and pressure ranging from 1.08 to 1.41 kbar. Miocene volcanics were crystallized at highly oxidized conditions, which are characterized by high oxygen fugacity of 10^?12.0 (HM) at temperature of 875 °C and pressure of 2.09 kbar. The wide range of obtained temperatures for clinopyroxenes of the suites denotes that the equilibration of clinopyroxene crystals initiates from depth until close to the surface before magma eruption. The compositional variations, resorbed core and reverse zoning patterns in clinopyroxene phenocrysts, as well as variable pressures of crystallization, further indicate that the magmas that formed the suites were polybaric in origins and were composite products of more than one petrogenetic stage. The observed range of phenocryst assemblage and different compositional trends possibly originated from fractionation of magmas with different initial water contents under variable pressures of crystallization. The repeated occurrence of magmas from different suites during a single period of activity suggests that the magmatic system consists of several conduit systems and that magma reservoirs are dispersed at different levels of crustal magma chambers.  相似文献   

Economic benefit assessment of the geo-hazard monitoring and warning engineering system in the Three Gorges Reservoir area: a case study of the landslide in Zigui     

Yu  Shiwei  Hou  Jindong  Lv  Jun  Ba  Guizhi 《Natural Hazards》2014,75(2):219-231

The completion and operation of the Three Gorges Reservoir in China have increased the frequency of geo-hazards and dangers in the area. To monitor and to warn of geo-hazards effectively, the Chinese government has invested billions of funds for constructing a monitoring and warning engineering system. Similar to other social infrastructure investments, a reasonable assessment of investment returns is necessary. Therefore, this study proposes an economic benefit assessment model, which considers both the expected and the actual values. The economic benefit of the geo-hazard monitoring and warning engineering in the Three Gorges Reservoir areas is evaluated. Based on the engineering characteristics, the model reasonably defines the frontier of the input and output and adds the casualties and the losses of ecological environment into the economic benefit evaluation index system. A case study on the Zhangjiawan landslide in Guojiaba Town, Zigui County, was conducted. The evaluation results show that (1) land has the largest benefit in direct reductional loss (total of 56.7 %), while the largest indirect reductional losses of the hazard-bearing bodies are in agricultural production and ecological environment (total of 97.6 %); (2) the costs-to-expected return ratio of landslide monitoring and warning engineering is 1:280, whereas the cost-to-actual benefit ratio is 1:30; (3) the accumulation of relevant information and the public knowledge of geological disasters should be strengthened.

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Theory of Accretion onto Neutron Stars     

G. Alojandc  S. Kamara  M. Ba  F. Ulara 《Astrophysics》2004,47(4):513-518

Hydrodynamically stationary, spherically symmetric accretion onto a neutron star is examined taking the reverse effect of radiation into account. It is assumed that the plasma flow is adiabatic and that radiation is generated in a thin surface layer of the neutron star, where incoming particles are slowed down. It is shown that for stationary accretion, neither a stop, nor a substantial slowing down of the accretion flux is possible for any physically allowed conditions far from the neutron star.  相似文献   

Issues with the earthquake vulnerability of Istanbul     

Eser Çaktı 《Natural Hazards》2013,68(1):227-228

Istanbul today is probably unique in the world not only in terms of the recognition of its earthquake risk by its inhabitants and administrators, but also in terms of significant steps taken in a such a short time toward the mitigation of its earthquake vulnerabilities. This paper, however, deals with the issues that still remain unattended.  相似文献   

Energy of a Stringy Charged Black Hole in the Teleparallel Gravity     

Mustafa Saltı 《Astrophysics and Space Science》2006,306(4):201-204

We use the teleparallel geometry analog of the Møller energy-momentum complex to calculate the energy distribution (due to matter plus field including gravity) of a charged black hole solution in heterotic string theory. We find the same energy distribution as obtained by Gad who investigated the same problem by using the Møller energy-momentum complex in general relativity. The total energy depends on the black hole mass M and charge Q. The energy obtained is also independent of the teleparallel dimensionless coupling constant, which means that it is valid not only in the teleparallel equivalent of general relativity, but also in any teleparallel model. Furthermore, our results also sustains (a) the importance of the energy-momentum definitions in the evaluation of the energy distribution of a given spacetime and (b) the viewpoint of Lessner that the Møller energy-momentum complex is a powerful concept of energy and momentum.  相似文献   

Cosmological Models with Variable G and Λ     

Can Battal Kılınç 《Astrophysics and Space Science》2004,289(1-2):103-109

Einstein's equations with variable gravitational and cosmological constants are considered in the presence of a perfect fluid for the anizotropic Bianchi I universe in a way which conserving the energy-momentum tensor. Two solutions are found, one of which the cosmological term varies inversely with power law of time. The other of which cosmological term is constant.  相似文献