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1.
Climate is one of the many factors such as socio-cultural structure, economy, materials, and technology that influence architectural forms. The resolutions that exist as a result of the effect of climate on architecture differ according to regions, cultures, time and technology. The climate in the Eastern Black Sea region, which lies in the north of Turkey, plays an active role in the formation and diversity of the vernacular houses in the region. Climatic factors such as rain, wind, humidity and sunlight in the region, which has a warm-humid climate and which gets excessive rain, have different effects on the spaces, elements and annexes of the vernacular houses. This study explains climatic approaches that are evident in the architecture of the vernacular houses in the Eastern Black Sea region. The aim of this study is to give information about the vernacular architecture in the Eastern Black Sea region and to investigate the relationship between the architectural products and the climate that plays a very important role in the formation of this architecture. Thus, the effects of climatic factors, such as rain, wind, humidity and sunlight, on vernacular houses are explained in the topics as plan, external walls, roof and exterior of buildings.  相似文献   

2.
In a preliminary biomonitoring study, accumulated trace metal concentrations (Cd, Cu, Zn, Hg, Fe, Mn) have been measured in the mussel Mytilus galloprovincialis collected in the Black Sea, at 100 km from the Danube Delta in February 2001 and February 2002. Mussels were collected from four sites. In 2001 metal concentrations were determined in the whole soft body whereas, in 2002, the distribution of metals was evaluated in three different organs (gills, visceral mass and remaining tissues). The results obtained in 2002 confirmed those of 2001. For a given site, concentrations were always higher in the gills and visceral mass of mussels than in the remaining tissues. Principal component analysis allowed separating stations as a function of the metal concentrations in the organs. It is concluded that the mussels M. galloprovincialis are suitable biomonitors to assess changes in metal pollution in this coastal area of the Black Sea.  相似文献   

3.
Each day some 400–450 ton solid waste is dumped on land and in the sea and rivers in the coastal cities of the eastern Black Sea, creating serious environmental problems. The paper reports the engineering geological studies of a proposed landfill site for Trabzon, a major city in the region. Fieldwork included scan-line and seismic surveys as well as boreholes and in-situ testing. Water absorption tests indicated permeabilities in the order of 10−8 m/s.   相似文献   

4.
Differently than in the past, today environmental problems have local, national and international concern. The environmental problems in the Black Sea region are a good example for this phenomenon. These problems have affected all six countries that have shores with the Black Sea. The current study analyses these problems in detail. It intends to detect potential reasons for problems and provide suggestions to solve these problems by considering the economic dimensions. In addition, the impact of problems on the city life is examined. Also, the roles and importance of voluntary organizations on solving environmental problems are emphasized.  相似文献   

5.
郭钰颖  陈鑫  王树全 《矿产勘查》2022,13(10):1561-1567
尾矿中含有的重金属通过介质向环境缓慢释放,重金属进入土壤后,会对周围土壤、生态环境造成影响,危害人类身体健康和安全。本文以某金矿尾矿库为研究对象,对尾矿库流域内土壤重金属进行取样调查,确定尾矿库及周边土壤重金属污染现状,分析重金属来源及污染特征。对尾矿库及周边的土壤进行pH、氰化物、锑、砷、镉、铜、铅、锌、汞等元素含量测试,采用单项污染指数与内梅罗指数法进行重金属污染程度分析与评价;同时运用主成分分析法,探究尾矿库及周边区域土壤重金属形成原因和污染特征。研究结果表明:尾矿库流域内地表土样处于重污染状态,污染区主要集中在尾矿库东北侧,污染范围较大;氰化物、锑、镉、铜、铅、锌存在着不同程度的相关性,表明研究区内存在这6种元素不同程度的复合污染或这些元素具有同源性,重金属污染主要来源为矿石开采和工业活动等人为来源;土壤中砷的吸附、迁移与土壤pH值关系密切。调查和分析尾矿库土壤污染情况,查明尾矿库污染形成原因和污染特征,对尾矿库的综合治理具有重要意义。  相似文献   

6.
The protective effects of vitamins C and E against oxidative stress were evaluated in various tissues of thornfish Terapon jarbua exposed to copper. Preliminary bioassay tests performed with copper and T. jarbua revealed that 4.0, 2.5 and 1.0 mg L(-1) of copper were lethal (LC(100)), medial lethal (LC(50)) and sublethal (LC(0)) respectively. Oxidative stress parameters viz. lipid peroxidation, superoxide dismutase, catalase, glutathione peroxidase, and glutathione were evaluated in control and experimental fishes. Lipid peroxidation activity increased in tissues of copper exposed fishes, while the antioxidant system exhibited a reduction in their activity. On the contrary copper stressed fishes fed with vitamins C and E enriched pellet feed showed significant reduction in lipid peroxidation activity and the antioxidant levels increased reaching near normal levels comparable to control values. Bioaccumulation of copper was studied in addition to oxidative stress. Substantial copper residue was detected in the tissues of T. jarbua exposed to copper and the level of copper in tissues reduced when the fishes were treated with vitamins ensuring copper depuration and thereby protecting them against stress. We concluded that vitamin supplementation offered significant reduction of the oxidative stress mediated by copper and we discuss the possible application of vitamins in costal aquaculture process.  相似文献   

7.
Artificial radionuclides enter the Mediterranean Sea mainly through atmospheric deposition following nuclear weapons tests and the Chernobyl accident, but also through the river discharge of nuclear facility effluents. Previous studies of artificial radionuclides impact of the Mediterranean Sea have focussed on shallow, coastal sediments. However, deep sea sediments have the potential to store and accumulate pollutants, including artificial radionuclides. Deep sea marine sediment cores were collected from Mediterranean Sea abyssal plains (depth > 2000 m) and analysed for 239,240Pu and 137Cs to elucidate the concentrations, inventories and sources of these radionuclides in the deepest areas of the Mediterranean. The activity — depth profiles of 210Pb, together with 14C dating, indicate that sediment mixing redistributes the artificial radionuclides within the first 2.5 cm of the sedimentary column. The excess 210Pb inventory was used to normalize 239,240Pu and 137Cs inventories for variable sediment fluxes. The 239,240Pu/210Pbxs ratio was uniform across the entire sea, with a mean value of 1.24 × 10− 3, indicating homogeneous fallout of 239,240Pu. The 137Cs/210Pbxs ratio showed differences between the eastern (0.049) and western basins (0.030), clearly significant impact of deep sea sediments from the Chernobyl accident. The inventory ratios of 239,240Pu/137Cs were 0.041 and 0.025 in the western and eastern basins respectively, greater than the fallout ratio, 0.021, showing more efficient scavenging of 239,240Pu in the water column and major sedimentation of 137Cs in the eastern basin. Although areas with water depths of > 2000 m constitute around 40% of the entire Mediterranean basin, the sediments in these regions only contained 2.7% of the 239,240Pu and 0.95% of the 137Cs deposited across the Sea in 2000. These data show that the accumulation of artificial radionuclides in deep Mediterranean environments is much lower than predicted by other studies from the analysis of continental shelf sediments.  相似文献   

8.
Different pelagic areas of the Mediterranean Sea have been investigated in order to quantify physical and biological mixing processes in deep sea sediments. Herein, results of eleven sediment cores sampled at different deep areas (> 2000 m) of the Western and Eastern Mediterranean Sea are presented.210Pbxs and 137Cs vertical profiles, together with 14C dating, are used to identify the main processes characterising the different areas and, finally, controlling mixing depths (SML) and bioturbation coefficients (Db). Radionuclide vertical profiles and inventories indicate that bioturbation processes are the dominant processes responsible for sediment reworking in deep sea environments.Results show significant differences in sediment mixing depths and bioturbation coefficients among areas of the Mediterranean Sea characterised by different trophic regimes. In particular, in the Oran Rise area, where the Almeria-Oran Front induces frequent phytoplankton blooms, we calculate the highest values of sediment mixing layers (13 cm) and bioturbation coefficients (0.187 cm2 yr−1), and the highest values of 210Pbxs and 137Cs inventories. Intermediate values of SML and Db (~ 6 cm and ~ 0.040 cm2 yr−1, respectively) characterise the mesothrophic Algero-Balearic basin, while in the Southern Tyrrhenian Sea mixing parameters (SML of 3 cm and Db of 0.011 cm2 yr−1) are similar to those calculated for the oligotrophic Eastern Mediterranean (SML of 2 cm and Db of ~ 0.005 cm2 yr−1).  相似文献   

9.
Nutrient reduction measures have been already taken by wealthier countries to decrease nutrient loads to coastal waters, in most cases however, prior to having properly assessed their ecological effectiveness and their economic costs. In this paper we describe an original integrated impact assessment methodology to estimate the direct cost and the ecological performance of realistic nutrient reduction options to be applied in the Southern North Sea watershed to decrease eutrophication, visible as Phaeocystis blooms and foam deposits on the beaches. The mathematical tool couples the idealized biogeochemical GIS-based model of the river system (SENEQUE-RIVERSTRAHLER) implemented in the Eastern Channel/Southern North Sea watershed to the biogeochemical MIRO model describing Phaeocystis blooms in the marine domain. Model simulations explore how nutrient reduction options regarding diffuse and/or point sources in the watershed would affect the Phaeocystis colony spreading in the coastal area. The reference and prospective simulations are performed for the year 2000 characterized by mean meteorological conditions, and nutrient reduction scenarios include and compare upgrading of wastewater treatment plants and changes in agricultural practices including an idealized shift towards organic farming. A direct cost assessment is performed for each realistic nutrient reduction scenario. Further the reduction obtained for Phaeocystis blooms is assessed by comparison with ecological indicators (bloom magnitude and duration) and the cost for reducing foam events on the beaches is estimated. Uncertainty brought by the added effect of meteorological conditions (rainfall) on coastal eutrophication is discussed. It is concluded that the reduction obtained by implementing realistic environmental measures on the short-term is costly and insufficient to restore well-balanced nutrient conditions in the coastal area while the replacement of conventional agriculture by organic farming might be an option to consider in the nearby future.  相似文献   

10.
The soils affected by the spill of a pyrite mine were analysed in 100 sampling points at three depths (0-10, 10-30, and 30-50 cm) in 1998 (after the tailings were removed), 1999 (after the cleaning of the highly contaminated areas), and 2004 (after the tilling of the upper 20-25 cm). The comparative study reveals that the removal of the tailings left a heterogeneous distribution pattern of the contaminants, with highly polluted spots alternating with less contaminated areas. The cleanup did not substantially lower the concentration in the highly polluted soils, and the spread of the pollutants increased the concentration in As and Pb in the uppermost 10 cm of 60% of the soils, while the Zn and Cd concentrations increased in only 30% of the soils. Given the high concentration of pollutants in the topsoil (especially As), the tilling of the upper 20-25 cm, despite reducing the average concentration of pollutants in the uppermost 10 cm, did not substantially lower the percentage of soils that exceeded the concentration of 40 mg As kg− 1 dry soil and almost doubled the percentage of soils that surpassed this concentration between 10 and 30 cm. Meanwhile, the displacement of Zn and Cd within the soil supported the reduction in the percentage of soils that in the upper 10 cm exceeded the reference concentrations of these elements (900 mg Zn kg− 1 dry soil and 2 mg Cd kg− 1 dry soil), and the percentage of soils exceeding these concentrations between 10 and 50 cm in depth did not increase. Six years after the spill and at the end of all remediation measures, the intervention levels defined by the Environmental Agency of the Regional Government of Andalusia for natural parks were exceeded in the uppermost 10 cm in 35% of the soils.  相似文献   

11.
'Natural' treatment systems such as wetlands and reed beds have been proposed as sustainable means of reducing fluxes of faecal indicator organisms (FIOs) to recreational and shellfish harvesting waters. This is because FIO fluxes to coastal waters from both point (effluent) and diffuse (catchment) sources can cause non-compliance with microbiological standards for bathing and shellfish harvesting waters. The Water Framework Directive requires competent authorities in the member states to manage both point and diffuse sources of FIOs in an integrated manner to achieve compliance with 'good' water quality as defined in a series of daughter Directives. This study was undertaken to investigate the relative sources of FIOs to the popular bathing waters around Clacton, UK. In this predominantly arable (mainly cereal cropping) farming area, the principal land use predictor, explaining 76% of the variance in geometric mean presumptive Escherichia coli concentration at sub-catchment outlets during the bathing season, was the proportion of built-up (i.e. urbanised) land in each sub-catchment. This new finding contrasts with earlier studies in livestock farming regions where the proportion of improved grassland has proven to be the strongest predictor of microbial concentration. Also novel in this investigation, a flood defence wall has been built creating a wetland area which discharges every tidal cycle. The wetland produces over 97% reduction in the flux and concentrations of FIOs to the marine recreational waters. Also, FIO concentrations in water draining through the wetland to the sea were similar to concentrations measured in six UK sewage treatment plant effluents subject to secondary (biological) treatment followed by UV disinfection.  相似文献   

12.
The deteriorating eutrophic state of the northern Adriatic Sea led to the commissioning of a study between 1977 and 1979 to identify the sources and forms of the nutrients phosphorus and nitrogen discharged from the basin of the river Savio. The study investigated the reduction in the phosphorus load in sewage per head of population caused by a reduction in the phosphorus content of detergents used in the basin and by the use of septic tanks. The flow and nutrient loads carried by the river were monitored during dry and wet weather to establish annual nutrient loads carried to the sea. An extensive sampling programme was carried out to quantify the principal sources of nutrients of which the most important were pig farming, Man and chemical fertilisers. An attempt was made to balance the nutrient loads discharged from the basin.  相似文献   

13.
This paper discusses the results of geophysical and chemical investigations carried out in a chemical munition dumpsite in the southern Baltic Sea, east of the island of Bornholm. After WW2 over 32,000 tons of chemical war material was dumped here including shells and bombs as well as small drums and containers. The geophysical investigations combined very-high-resolution seismics and gradiometric measurements. The results indicate the presence of a large number of objects buried just below the seafloor. The size of the objects and their distribution, with a marked increase in density towards the center of the dumpsite, suggests that we are dealing with dumped war material. Sediment and near-bottom water samples, taken within the dumpsite and in the surrounding area, were analysed for the presence of various chemical warfare agents (CWA) including Adamsite, Clark, sulphur mustard, tabun, chlorobenzene and arsine oil. The results indicate a widespread contamination that reaches far beyond the dumpsite boundary. CWA degradation products were found in most of the sediment samples. The contamination was mostly related to arsenic containing compounds; only one sample indicated the presence of sulfur mustard. Although the correlation between detected objects and CWA concentrations is not always straightforward, the overall results suggest that a lot of the dumped war material is leaking and that over the years the contamination has reached the seafloor sediments.  相似文献   

14.
Mercury (Hg) and 13 other trace elements (Al, Ti, V, Cr, Fe, Mn, Co, Ni, Cu, Zn, As, Cd, and Pb) were measured in phytoplankton, zooplankton, mysis and herring in order to examine the trophodynamics in a well-studied pelagic food chain in the Baltic Sea. The fractionation of nitrogen isotopes (δ15N) was used to evaluate food web structure and to estimate the extent of trophic biomagnification of the various trace elements. Trophic magnification factors (TMFs) for each trace element were determined from the slope of the regression between trace element concentrations and δ15N. Calculated TMFs showed fundamental differences in the trophodynamics of the trace elements in the pelagic food chain studied. Concentrations of Al, Fe, Ni, Zn, Pb and Cd showed statistically significant decreases (TMF < 1) with increasing trophic levels and thus these trace elements tropically dilute or biodilute in this Baltic food chain. Cu, As, Cr, Mn, V, Ti and Co showed no significant relationships with trophic levels. Hg was unique among the trace elements studied in demonstrating a statistically significant increase (TMF > 1) in concentration with trophic level i.e. Hg biomagnifies in this Baltic food chain. The estimated TMF for Hg in this food chain was comparable to TMFs observed elsewhere for diverse food chains and locations.  相似文献   

15.
我国南海海域面临俯冲带地震的影响,海域俯冲带地震的工程特性是海域工程抗震研究的基础,为给海域工程地震危险性分析提供合理的地震动输入,对于没有实际地震动数据的我国南海海域,文中提出一种基于数值模拟结合其他区域已有经验衰减关系建立本地衰减关系的方法。该方法采用随机有限断层法分别对南海俯冲带和日本东北部俯冲带板内地震动进行模拟,以模拟的不同震级、不同距离下的大量地震动为基础,回归了日本俯冲带与南海俯冲带地震动衰减关系,并推导二者的定量关系,基于此定量关系和已知的日本东北部俯冲带板内地震的经验衰减关系,最终建立南海俯冲带板内地震动的衰减关系。将文中建立的南海地震衰减关系与日本以及汶川地震衰减关系进行对比,结果表明:不同类型的地震的衰减特征存在一定的差异性,海域俯冲带板内地震的衰减速率要快于我国陆地地区的汶川地震的浅地壳地震;数值模拟结合经验关系的混合方法得到的南海俯冲带板内地震动衰减关系具有一定的应用价值,此方法可为没有实际地震动的地区建立衰减关系提供参考,建立的衰减关系可为海洋工程和近海交通重大工程的建设提供依据。  相似文献   

16.
This paper presents a mine pillar design approach by combining finite element methods (FEMs), neural networks (NN) and reliability analysis. This practical approach is presented by examining an actual cylindrical mine pillar in a copper mine and taking into account uncertainties in ore pillar material parameters including modulus, Poisson's ratio, density and uniaxial compressive strength. The ore pillar had to be able to safely and effectively support a drilling room that occupied an open space of 3.8 m high and 55 m long and 20 m wide and at a depth of 360 m below ground surface. Three-dimensional FEM was used to simulate the mining operations and to estimate average pillar compressive stress at each operation step. A pillar performance function was established in implicit form taking into account pillar strength and pillar dimension. NN was incorporated in the FEM to substantially reduce the number of finite element calculations in establishment of the relationship between pillar compressive stress and basic random variables. Trained NN was then used to generate a database for the implicit performance function. The database was used to determine the reliability index and failure probability for each trial pillar diameter. Relationship between pillar reliability index and each of the coefficients of variation of the basic random variables was used for optimal design of pillar diameter. The optimal pillar design was used in the mining construction and functioned well.  相似文献   

17.
This study reports on the relationship between copper (Cu) behavior and organic matter (OM) transformation along the turbidity gradient in the freshwater reaches of the Gironde Estuary. During a one-year survey, surface water and suspended particulate matter (SPM) were sampled at least monthly at three sites along the Garonne Branch, representing the main fluvial branch of the Gironde Estuary. Additionally, a longitudinal high resolution profile was sampled along the Garonne Branch, covering the turbidity gradient from the river water endmember to the maximum turbidity zone (MTZ). Seasonal variability and spatial distribution of Cu in both the dissolved phases (< 0.2 μm, Cu0.2 and < 0.02 μm, Cu0.02) and particulate Cu (CuP) clearly suggested Cu0.2 addition during summer, that increased the Cu0.2 concentrations by a factor ~ 2, mainly manifested by an increase in the Cu0.02 fraction. At the annual timescale (2004), this internal Cu reactivity increased Cu0.02 fluxes in the Garonne Branch by ~ 20% (3.6 t year−1), with the equivalent of ~ 2.9 t year−1 derived from the CuP fraction and ~ 0.7 t year−1 from the colloidal (0.02-0.2 μm) fraction, without involving and/or affecting the CuC18 (hydrophobic metal-organic complexes) fraction.Combining data on Cu speciation with the results obtained by several independent techniques (DOC and POC measurements, 3D-fluorescence, and TEM) suggested close relationships between Cu behavior and OM transformation/restructuration along the turbidity gradient in the Garonne Branch. The observed Cu0.02 addition was related to increasing humification (humification index HIX increased from 9 to 12, network formation) and labile OM degradation (Iγ/Iα ratio decreased from 0.70 to 0.44), going along with decreasing DOC and POC concentrations. Mass-balances suggest that in the studied system, degradation of OM may account for the release of ~ 25 μmol potentially bioaccessible Cu0.02 per mole of particulate organic carbon mineralized.  相似文献   

18.
ABSTRACT

The paper reports a study of chromosome abnormalities (CA/s) in the Monopterus albus near a gold mine area compared to a non-affected area. The arsenic (As) concentrations were determined in the water, sediment and M. albus muscles. The average concentrations of As in the water and sediment samples near the gold mine were higher than allowable by Thailand’s water quality standards. The average concentrations of As in the M. albus samples were lower than the standards. The diploid chromosome number of M. albus in both areas was 2n = 24. The percentage of CA of M. albus in the gold mine area was higher than in the non-affected area. Seven types of CA were single chromatid gap (SCG), fragmentation (F), sister chromatid gap, single chromatid breaks, deletion, sister chromatid fragmentation and centric fusion. In the affected area, the most common CAs in the samples were SCG and F. The specific CA in M. albus samples was SCG on chromosome pair 1. It can be concluded that As contamination caused structural CA, but did not affect the diploid chromosome number in the Asian swamp eel from the gold mine area. The accumulation of As in M. albus has potential effects on human health in consumers of M. albus from this contaminated area.  相似文献   

19.
Metal contamination from acid mine drainage (AMD) is a serious problem in the southwest of the Iberian Peninsula, where the Iberian Pyrite Belt is located. This zone contains original sulfide reserves of about 1700 Mt distributed among more than 50 massive sulfide deposits. Weathering of these minerals releases to the waters significant quantities of toxic elements, which severely affect the sediments and surface waters of the region. The main goal of this paper is to evaluate the toxicity and the potential risk associated with the mining areas using Microtox test and different factors which assess the degree of contamination of the sediments and waters. For this, a natural stream polluted by AMD-discharge from an abandoned mine has been studied. The results show that elevated concentrations of Cu, As and Zn involve an important potential risk on the aquatic environment, associated both with sediments and waters. Microtox test informs that the sediments are extremely or very toxic, mainly related to concentrations of Fe, As, Cr, Al, Cd, Cu and Zn. Pollution is mainly transferred to the sediments increasing their potential toxicity. A natural creek affected by AMD can store a huge amount of pollution in its sediments while exhibiting a not very low water pH and low water metal concentration.  相似文献   

20.
The seasonal variations in the trace element concentrations and flow rates in the Carnon River system, south west England have been investigated on a monthly basis for a period of 1 yr. Approximately 85% of Fe, Zn and As, and 45% of Cu originate from mine waters. A strong seasonal dependence of the flux of trace elements in the natural and mine waters is observed. There appears to be a direct correlation between trace element concentrations and the proportion of infiltrated surface drainage in mine waters. Rises in these concentrations in the Carnon River due to increased fluxes from mine waters in winter months are offset by higher flow rates in surface discharge.Iron is transported predominantly in the particulate phase in Carnon River waters and virtually all dissolved Fe (< 0.45 μm) precipitates in estuarine waters. Dissolved concentrations of Cu, Zn and As appear to be regulated by sorptive processes particularly with Fe oxyhydroxides in both fresh and saline waters.  相似文献   

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