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1.
Doklady Earth Sciences - From December 2020 to April 2021, in the northwestern part of the Kola Peninsula, including the infrastructure of the city of Murmansk, the quantity of polymer particles in...  相似文献   

2.
Engineering activities lead to the anthropogenic transformation of engineering–geological conditions in different areas of Russia. A differential estimate has been made for changes in individual components of engineering–geological structures: relief, upper section soils, underground waters, depth of seasonal soil freezing and thawing, and current geological processes. The general integrated evaluation of the anthropogenic transformation of engineering–geological megastructures in Russia has been made on the basis of differential estimates of the components.  相似文献   

3.
Background： Fluorine is an important element to human health. Overloading of fluorine may cause dental and/or skeletal fluorosis, while in fluorine deficiency distracts, fluoride drinking water supply or other methods of fluoridation may greatly reduce the ratio of dental caries of local residents. The benefit of drinking water fluoridation has been widely accepted as a public sanitation measure in most western countries, but in China it faces big challenges. Method： Investigation of oral health and fluorine level in drinking water, main food and urine in some big cities of China. Result and conclusion： （1） Fluorine content in drinking water in 70% of the whole research cities is lower than 0.3 mg/L, and in 90% of the research cities, it is lower than 0.5 mg/L. （2） Fluorine concentrations in main foodstuff of respective cities in China were low and did not have too much difference. （3） Drinking water was the main source of fluorine intake for Chinese residents. （4） With the data of the epidemiological research by NCOH in 1995, in the range of fluorine content in drinking water below 1.0 mg/L, the ratio of dental caries and DMFT decreases with the increase of fluorine concentration. The relation between fluorine concentration in drinking water and dental index did not have a good linear relationship.  相似文献   

4.
The rapid industrial development in China has caused a range of environmental problems. Along with emissions of ＂conventional＂ air pollutants, such as sulfur and nitrogen oxides, there are also increasing emissions of heavy metals to the atmosphere. Little information is available on metal contamination due to atmospheric deposition in forest soils in China. In order to get an overview of the extent of the problem, we conducted analyses of metal content in soil samples from three forested research catchments in Southwest China [Tieshanping （TSP） in Chongqing, Liuchongguan （LCG） and Leigongshan （LGS） in Guizhou]. Total concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, Sn and Zn were determined by Inductively Coupled Plasma-Mass Spectrometry after microwave digestion. The Hg content was determined using a Direct Mercury Analyzer. The concentrations of most of the analyzed metals were below the National Grade A standard limits in China for most samples, except for Cd and Pb where the limits were slightly exceeded at some of the sampling sites. In general, there were small differences between the different sites, although Cd and Co show a tendency to be higher at the most remote site （Leigongshan）. This site receives the lowest deposition of conventional air pollutants among the sites and the higher metals concentrations are possibly related to higher content in the soil parent material. There is no apparent general gradient in metal concentrations with proximity to cities, major air pollution emission sources, nor with sulphur deposition loads.  相似文献   

5.
Total and bioavailable concentrations of rare earth elements （REEs） in the latesol of Hainan Province, China, were measured by ICP-MS, and the distribution characteristics of REEs were discussed in various latesol profiles. The results show that the total concentrations of REEs were higher than the average statistical data of the whole China. The correlation coefficients between the total and bioavailable concentrations of REEs were from 0.66 to 0.95 （P〈0.001, n=63）. This suggests that it is necessary to study the bioavailable and total heavy metal concentrations in soils in order to assess the ecological and environmental effects, and to provide scientific information on REEs application as micro-elemental fertilizers, and consequently their potential health risks. The percentage of the bioavailable concentrations in the latesol derived from some kinds of parent materials was up to 50%, indicating that it was unnecessary to apply REE micro-elemental fertilizers in the soils.  相似文献   

6.
Arsenic is the 20th most abundant element in the Earth crust. Humans are exposed to naturally occurring and anthropogenic sources of arsenic compounds in the environment. A wide variety of adverse health effects have been attributed to chronic exposure to high levels of arsenic. More than two-dozen arsenic compounds （species） are present in the environment and in biological systems. The various arsenic species have dramatically different behavior and toxicity. This presentation briefly describes arsenic speciation analysis, human exposure to and metabolism of arsenic species. Environmental issues on arsenic in Canada are briefly discussed. These include （1） the arsenic waste left from previous gold mining and smelting activities; （2） the domestic use of wood treated with chromated copper arsenate; and （3） use of well water as the source of drinking water by approximately one third of the Canadian population.  相似文献   

7.
Votalization of selenium in selenium-rich black rock series in Yutangba is discussed at 400, 500, 600, 700, 800 and 900℃.Votalization of selenium tends to increase when the temperature is high. So environmental influence of selenium-rich black rock series combustion needs to be considered.  相似文献   

8.
The first data were obtained on the total mercury content in hydrobionts and their habitat in Grønfjorden, Spitsbergen, at the waste discharge sites of the settlement of Barentsburg in early spring 2017. The Hg concentration was below the detection limit in the water and varied from 7.1 to 42.3 ng/g of dry weight in the bottom sediments. Mercury concentration in the hydrobionts increased toward the inner fjord and was higher near the mouth of the Grøndalen River, which flows into the fjord. Elevated Hg concentrations at the mouth of the Grøndalen River indicate that much of the toxic metal is brought to the inner part of the fjord with riverine runoff, and this Hg source is likely more important than the surface supply of Hg transferred from local surface pollution centers at Barentsburg. The Hg concentration depended on the position of the marine organisms in the trophic chain and was the highest in the detritophage mollusks Thyasira gouldi, Cardium sp., and Macoma calcarea, the specialized predatory sea snail Cryptonatica affinis, and the cod Gadus morhua, which is a benthosophage–secondary predator. The total Hg concentrations in the hydrobionts and their habitat in Grønfjorden were generally relatively low and close to the background one.  相似文献   

9.
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10.
Bernd LEHMANN 《地质学报》2014,88(Z2):258-259
Please refer to the attachment(s) for more details.  相似文献   

11.
Three hundred and six coal samples were taken from the main coal mines of twenty-six provinces, autonomous regions, and municipalities of China. The method of Kjeldahl-Gunning Analysis was used to measure the nitrogen contents in the samples. Nitrogen in coals is principally of organic nature. A weak positive correlation between coal rank and nitrogen content is inferred in the study. The distribution of nitrogen in each geological age, coal-cumulating area and province＇s coals was studied. The contents of nitrogen in Chinese coals show approximately a normal distribution, and 90% of the values range from 0.52% to 1.41%, the average nitrogen content in Chinese coals is designated as the arithmetic mean, 0.98%.  相似文献   

12.
Spatial variations in the relationship between topography and mean annual and seasonal rainfalls in southwestern Saudi Arabia are examined using Kruskal–Wallis one-way analysis of variance. The topographic factors include physiographic features (topography), altitude, slope, proximity to a ridge or crest of mountains, and proximity to the Red Sea. There is a statistically significant effect of topographic factors on the mean annual rainfall, but the results are more significant for the mean seasonal rainfall. The largest amount of mean rainfall in the study area occurs during spring, when rainfall displays a significant relationship with topographic factors, in which more orographic rainfall patterns are associated with higher altitude, greater proximity to a ridge and steeper slopes. Higher altitudes do not necessarily receive more rain; some low altitude locations (i.e., the southern part of the study area) receive more rain during summer and fall because they are located on the windward side of the Asir Mountains and are exposed to the moist air masses brought by the southwest monsoonal system in summer and by the northwest air flow from the Mediterranean and Red Sea in the fall in addition to local convective rainfall patterns. Rainfall in winter increases in the foothills of the Asir Mountains above the coastal plain of the Red Sea. The steep western slopes (windward side) receive more rainfall than the gentle eastern slopes (leeward side): this may be due to the Asir Mountains forcing moist air masses carried by the westerly and northwest winds to rise and cool before they descend and warm on the leeward side.  相似文献   

13.
The data of rogue wave accidents reported in mass media during 2006–2010 years are collected and analysed. The collection includes 106 events, which are classified by their validity as true (78) and possible (28) and by the location of their occurrence: we distinguish deep, shallow and coastal rogue waves, which occurred in deep/shallow waters or at the coast. The validity of the event has been estimated by the rogue wave height, which should be twice larger than the significant wave height (significant wave height has been taken from satellite data), and/or by the associated hazard. It is shown that rogue waves cause especially high damage in shallow waters and at the coast.  相似文献   

14.
This article is complementary to Claudio Margottinis technical article Instability and geotechnical problems of the Buddha niches and surrounding cliff in Bamiyan Valley, central Afghanistan, published in Vol. 1, issue 1 of this journal. The present article provides background information on the framework of UNESCOs strategies for the safeguarding of Afghanistans cultural heritage and, in particular, the Bamiyan site, the mechanisms for the development of operational projects, capacity building of national specialists, UNESCOs partnerships and its fund-raising activities for the successful implementation of projects. The Division of Cultural Heritage is closely involved in ICL, therefore, it was natural to include UNESCOs project for the safeguarding of the Bamiyan site in the framework of IPL. It was approved as IPL project C101-3 titled The geo-morphological instability of the Buddha niches and surroundings cliffs in the Bamiyan Valley.The author is program specialist in charge of Asia at UNESCOs Division of Cultural Heritage and member of ICL  相似文献   

15.
Paul Richards 《GeoJournal》1999,47(3):433-442
Mary Douglas (1993) has indicated some of the shared concerns that keep voluntary enclaves together as ‘social movements’. The present paper describes a rather different kind of enclave politics, being concerned with the ‘new violence’ of groups enclaved by social exclusion and force. The paper focuses on the emergence and subsequent development of dissidents in the civil war in Sierra Leone. The RUF was at the outset a tiny but conventional guerrilla force, modelled on one of the militias in the Liberian civil war, and seeking to overthrow a decayed neo-patrimonial ‘one-party’ regime. Gaining little popular support, its members became marooned in forested isolation on the Liberia-Sierra Leone border. Recruits were mainly school children seized by force and ‘converted’ through having to take part in atrocities against rural civilians. Unable to return to the larger society on pain of summary execution, captives have had little option but to adjust to the political fantasies of a violent and unstable leadership. They were enclaved by force. Indicating the predictive strength of Douglas' arguments about the cultural dynamics of the enclave, the subsequent atrocity-drenched story of the RUF suggests that it is not the content of belief that determines institutional culture but vice versa. To survive, the enforced enclave develops the concerns of the classic ‘sect’ - a doctrinaire ‘rationality’ (expressed in crude acts of ‘subtractive’ violence), rejection of magic, decision making by lots, preoccupation with defection, otiose leadership style. If the rest of the world is to come to terms with violent enclave organizations such as the RUF and Algerian GIA it may have to pay more careful attention to the way enclave institutions think. They may not respond ‘rationally’ to the kinds of incentives offered by mainstream groups organised around hierarchical and/or individualist systems of social accountability. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

16.
The paper presents an example of the application of remote-sensing techniques in peat resource investiga-tions. The study was carried out in the Zoige region. The optimal imagery time (during October) and theoptimal band (MSS_7) of Landsat data were selected. The preferred images were processed optically and bycomputer and interpreted in a comprehensive way. And in-situ spectrum measurements and drilling verificationwere carried out.The identification signature of the peat bogs in Zoige was defined. The feature of the identifi-cation signature for peat was that the peat bog area showed a dark tone with lower reflectance in images of thefour MSS bands. The distribution range of peat bogs in the region was exactly located. The types of peat bogswere distinguished. The total peat area of 4038 km~(2) was defined with a total reserve of 5 billion m~3. The resultof the study indicates that the large-area, small-scale investigation of peat resources by use of satelliteremote-sensing data is an advanced method. by which the work efficiency can increase by about 20 times.  相似文献   

17.
A detrital zircon aged 4.1 Ga is discovered by the SHRIMP U-Pb method in a quartzite in Burang County, western Tibet. This is presently the oldest single-grain detrital zircon in China. The Th-U ratios of the two testing points of the 〉4.0 Ga zircon are between 0.76 and 0.86, indicating their magmatic origin. This discovery has offered an important age for investigating the geological evolution of the Qinghai-Tibet Plateau.  相似文献   

18.
The paleoforest remains studied are distributed within a range of 18000 m^2 in the intertidal zone of the Qianhu Bay, Fujian Province. Eighty-nine ancient tree stumps can be clearly recognized in the paleoforest remains. Microscopic studies of 10 relatively low-carbonized stump samples definitely showed four species： Glyptostrobus pensUi （Staunt） Kouch, Schima superba Gardn., Cinnamomum Schaeffer, and Litsea Lam. The 14^C dating of some samples yielded the ages of 42560±350 to 〉43000 a B. P., corresponding to the late Late Pleistocene.  相似文献   

19.
English summary Near the eastern base of the Taconic Range, in extreme southwestern Vermont, a complex of chlorite slate is exposed in the position of the floor of a thrust along which a mass of dolomite-limestone has been pushed from the east against, and over, the slate. In addition to the common structure, exhibiting westward-overturned open folds, with slip cleavage dipping eastward, about parallel with the axial pianos, the slate displays a number of subsidiary shears or thrust zones having the same orientation as the principal thrust. In these zones, a strong lineation as well as axes of small folds plunge E—SE, parallel with the direction of propagation of the thrust blocks. The origin of the lineation and lamination is believed to be identical with that of corresponding structures in rolled steel and glass.However, the formation of folds with axes parallel to the direction of thrust requires an additional shear stress acting perpendicularly to the direction of thrusting. The inhomogeneous composition, strength, and mobility of the flooring rocks are pointed out, and it is suggested that unequal rates of yielding of local rock masses below the thrust block generated these supplementary stresses, producing slight movements of small masses sideways. That this is a reasonable explantation is shown by experiments on salt dome structure byEscher andKuenen, in which also axes of folds and lineation parallel with the direction of maximum forward propagation were produced.  相似文献   

20.
INTRODUCTION Microfossilsaregenerallythemostversatileand “useful”offossilsforbothcorrelationandagedeter minationandpaleoenvironmentalanalysis.Among microfossilstheforaminiferaarepre eminent(Fig. 1).Wefindinthesamesample—beitoutcropor subsurface,onshor…  相似文献   

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