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1.
At 31 sites in Finland the Zn content was determined of the epiphytic lichen Hypogymnia physodes (L.) Nyl. growing on pine and birch, the terricolous lichen Cladina spp. in pine bark, and the inner part of birch bark. The anomalous contents of Zn in H. physodes on pine and Cladina spp. in soil appeared to be strongly related to sulphide ore deposits. Anthropogenic Zn correlated closely with S and Fe in H. physodes on pine and with Fe in Cladina spp. The binding of geogenic Zn was related to iron hydroxides, and was attributed to the different uptake mechanism of S in these lichens. Elevated values of Zn in H. physodes on birch were due to both geogenic and anthropogenic sources. Zinc in pine bark increased with the Zn content in H. physodes and reached a limiting value. 相似文献
2.
Lake and reservoir water quality affected by metals leaching from tropical soils, Bangladesh 总被引：2，自引：0，他引：2
Md. R. Islam W. P. Lahermo R. Salminen S. Rojstaczer V. Peuraniemi 《Environmental Geology》2000,39(10):1083-1089
The release of metals during weathering has been studied in order to assess its geochemical controls and possible effects
on environmental health in Bangladesh. A total of 27 soil samples and 7 surface water samples were collected from four locations
covering three major regions in the country. Results show that weathering effects are a strong function of climatic conditions.
Surface waters are typically enriched in Al, Mg, Ca, Na, K, As, Ba, Cr, Cu, Ni, Pb and Zn. The solubility of metal ions, organometallic
complexes, co-precipitation or co-existence with the colloidal clay fraction are the main processes that lead to metal enrichment
in lake and reservoir water. Aluminium concentrations exceed World Health Organization (WHO) drinking-water standards in all
samples, and in two regions, arsenic concentrations also significantly exceed WHO standards. The elevated levels of As indicate
that arsenic contamination of water supplies in Bangladesh is not confined to groundwater.
Received: 4 June 1999 · Accepted: 17 August 1999 相似文献
3.
To simulate the behavior of As and S in the formation of till, the contents of these elements were determined in the total material, the −0.064 mm fraction and the 0.064–0.5 mm fraction of crushed rock samples. For most of the studied rock types there was a conspicious enrichment of As and a much less prominent enrichment of S in the finest fraction. Accordingly, in the formation of till the mere mechanical crushing of rock material can create enrichment of the derived till. 相似文献
4.
Salminen Sarianna Tammelin Mira Jilbert Tom Fukumoto Yu Saarni Saija 《Journal of Paleolimnology》2021,66(3):207-227
Journal of Paleolimnology - The influence of lake restoration efforts on lake bottom-water conditions and varve preservation is not well known. We studied varved sediments deposited during the last... 相似文献
5.
Reijo Salminen Anne Kousa Rolf Tore Ottesen Olle Selinus Eiliv Steinnes Timo Tarvainen Bjoern OEhlander 《《幕》》2008,31(1):155-162
The mining environment, medical geology and urban geochemistry form a group of related scientific disciplines that have developed strongly during recent years in the Nordic countries. Modern legislation controls the environmental issues. Close co-operation of researchers and legislators has improved the quality and safety of life in the societies of the Nordic countries. In mining environmental studies, methods that are suitable in Arctic conditions have been developed; in medical geology, the input from the Nordic countries has made it an appreciated scientific discipline throughout the world, and in the case of the urban environment, methods developed by our geochemists have especially improved the health conditions, particularly of children. 相似文献
6.
J. Salminen F. Donadini L. J. Pesonen V. L. Masaitis M. V. Naumov 《Meteoritics & planetary science》2006,41(12):1853-1870
Abstract— Paleomagnetic, rock magnetic, and petrophysical results are presented for impactites and target rocks from the Lake Jänisjärvi impact structure, Russian Karelia. The impactites (tagamites, suevites, and lithic breccias) are characterized by increased porosity and magnetization, which is in agreement with observations performed at other impact structures. Thermomagnetic, hysteresis, and scanning electron microscope (SEM) analysis document the presence of primary multidomain titanomagnetite with additional secondary titanomaghemite and ilmenohematite. The characteristic impact‐related remanent magnetization (ChRM) direction (D = 101.5°, I = 73.1°, α95 = 6.2°) yields a pole (Lat. = 45.0°N, Long. = 76.9°E, dp = 9.9°, dm = 11.0°). Additionally, the same component is observed as an overprint on some rocks located in the vicinity of the structure, which provides proofs of its primary origin. An attempt was made to determine the ancient geomagnetic field intensity. Seven reliable results were obtained, yielding an ancient intensity of 68.7 ± 7.6 μT (corresponding to VDM of 10.3 ± 1.1 times 1022 Am2). The intensity, however, appears to be biased toward high values mainly because of the concave shape of the Arai diagrams. The new paleomagnetic data and published isotopic ages for the structure are in disagreement. According to well‐defined paleomagnetic data, two possible ages for magnetization of Jänisjärvi rocks exist: 1) Late Sveconorwegian age (900–850 Myr) or 2) Late Cambrian age (?500 Myr). However, published isotopic ages are 718 ± 5 Myr (K‐Ar) and 698 ± 22 Myr (39Ar‐40Ar), but such isotopic dating methods are often ambiguous for the impactites. 相似文献
7.
Linkin V Harri AM Lipatov A Belostotskaja K Derbunovich B Ekonomov A Khloustova L Kremnev R Makarov V Martinov B Nenarokov D Prostov M Pustovalov A Shustko G Jarvinen I Kivilinna H Korpela S Kumpulainen K Lehto A Pellinen R Pirjola R Riihela P Salminen A Schmidt W McKay CP 《Planetary and Space Science》1998,46(6-7):717-737
A mission to Mars including two Small Stations, two Penetrators and an Orbiter was launched at Baikonur, Kazakhstan, on 16 November 1996. This was called the Mars-96 mission. The Small Stations were expected to land in September 1997 (Ls approximately 178 degrees), nominally to Amazonis-Arcadia region on locations (33 N, 169.4 W) and (37.6 N, 161.9 W). The fourth stage of the Mars-96 launcher malfunctioned and hence the mission was lost. However, the state of the art concept of the Small Station can be applied to future Martian lander missions. Also, from the manufacturing and performance point of view, the Mars-96 Small Station could be built as such at low cost, and be fairly easily accommodated on almost any forthcoming Martian mission. This is primarily due to the very simple interface between the Small Station and the spacecraft. The Small Station is a sophisticated piece of equipment. With the total available power of approximately 400 mW the Station successfully supports an ambitious scientific program. The Station accommodates a panoramic camera, an alpha-proton-x-ray spectrometer, a seismometer, a magnetometer, an oxidant instrument, equipment for meteorological observations, and sensors for atmospheric measurement during the descent phase, including images taken by a descent phase camera. The total mass of the Small Station with payload on the Martian surface, including the airbags, is only 32 kg. Lander observations on the surface of Mars combined with data from Orbiter instruments will shed light on the contemporary Mars and its evolution. As in the Mars-96 mission, specific science goals could be exploration of the interior and surface of Mars, investigation of the structure and dynamics of the atmosphere, the role of water and other materials containing volatiles and in situ studies of the atmospheric boundary layer processes. To achieve the scientific goals of the mission the lander should carry a versatile set of instruments. The Small Station accommodates devices for atmospheric measurements, geophysical and geochemical studies of the Martian surface and interior, and cameras for descent phase and panoramic views. These instruments would be able to contribute remarkably to the process of solving some of the scientific puzzles of Mars. 相似文献
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9.
Charles S. Cockell Pascal Lee Paul Broady Darlene S. S. Lim Gordon R. Osinski John Parnell Christian Koeberl Lauri Pesonen Johanna Salminen 《Meteoritics & planetary science》2005,40(12):1901-1914
Abstract— Asteroid and comet impacts can have a profound influence on the habitats available for lithophytic microorganisms. Using evidence from the Haughton impact structure, Nunavut, Canadian High Arctic, we describe the role of impacts in influencing the nature of the lithophytic ecological niche. Impact‐induced increases in rock porosity and fracturing can result in the formation of cryptoendolithic habitats. In some cases and depending upon the target material, an increase in rock translucence can yield new habitats for photosynthetic cryptoendoliths. Chasmoendolithic habitats are associated with cracks and cavities connected to the surface of the rock and are commonly increased in abundance as a result of impact bulking. Chasmoendolithic habitats require less specific geological conditions than are required for cryptoendolithic habitats, and their formation is likely to be common to most impact events. Impact events are unlikely to have an influence on epilithic and hypolithic habitats except in rare cases, where, for example, the formation of impact glasses might yield new hypolithic habitats. We present a synthetic understanding of the influence of asteroid and comet impacts on the availability and characteristics of rocky habitats for microorganisms. 相似文献
10.
The distribution of As in a variety of sample materials was studied at different scales, from continental to local, combining published data sets with the aim of delineating the impact and relative importance of geogenic vs. anthropogenic As sources. Geochemical mapping of As with a variety of sample materials demonstrates that variation is high at all scales (local to continental) – from sample densities of 400 sites per km2 to 1 site per 5000 km2. Different processes govern the As distribution at different scales. A high sample density is needed to reliably detect mineralisation or contamination in soil samples. In both cases the impact on the much larger geochemical background variation is limited to a local scale. Distribution patterns in geochemical maps on the sub-continental to continental scale are dominated by natural variation. Given that the geochemical background is characterised by a high variation at all scales, it appears impossible to establish a reliable single value for “good soil quality” or a “natural background concentration” for As for any sizeable area, e.g., for Europe. For such a differentiation, geochemical maps at a variety of scales are needed. 相似文献