The sedimentary fill of the Baikal Basin: Implications for rifting age and geodynamics     

V.D. Mats 《Russian Geology and Geophysics》2012,53(9):936-954

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Theoretical and practical aspects on benthic quality assessment according to the EU-Water Framework Directive – Examples from Swedish waters     

Kjell Leonardsson  Mats Blomqvist  Rutger Rosenberg 《Marine pollution bulletin》2009,58(9):1286-1296

A previously presented objective method to calculate each species sensitivity to disturbance is here slightly modified and implemented in the Benthic Quality Index (BQI) for marine benthic invertebrates. A framework for assessment of water bodies based on multi-site BQI-values is also presented, where a certain variation of BQI-values is allowed to cover the heterogeneity within each water body. The 20th percentile, using bootstrapping, from the available sites’ BQI-values is compared with the status boundaries for quality assessment. The reliability of the assessment depends on the background information available for the boundary setting as well as the number of sampling sites included in the assessment. Agreement between time series of quality assessments in areas with known changes in anthropogenic disturbances is encouraging. Problems associated with water body assessment based on few or no samples, as well as multiple sampling occasions during the 6-yr WFD cycle are discussed.  相似文献   

Half‐a‐billion‐year‐old microscopic treasures—the Cambrian ‘Orsten’ fossils of Sweden     

Mats E. Eriksson  Dieter Waloszek 《Geology Today》2016,32(3):115-120

The creatures that gaze back at us through the binocular microscope are so uniquely well‐preserved and life‐like that had we not known better we would have thought that they were modern. Instead they are half‐a‐billion‐year‐old arthropods extracted from Cambrian rocks of Sweden. The microscopic fossils, colloquially known as the ‘Orsten’ fossils, are now world‐famous and basking in the light of the research catwalk since their discovery in the 1970s. These fossils have provided significant insight into the long lost Cambrian biotas and early animal evolution.  相似文献   

Contaminant exposure and effects in Baltic ringed and grey seals as assessed by biomarkers   总被引：3，自引：0，他引：3  

Nyman M  Bergknut M  Fant ML  Raunio H  Jestoi M  Bengs C  Murk A  Koistinen J  Bäckman C  Pelkonen O  Tysklind M  Hirvi T  Helle E 《Marine environmental research》2003,55(1):73-99

The Baltic Sea ecosystem has suffered from a heavy pollutant load for more than three decades. Persistent organic pollutants (POPs) and heavy metals have been of most concern due to their persistence and toxic properties. Ringed seals (Phoca hispida baltica) and grey seals (Halichoerus grypus) living in the Baltic Sea have been suffering from pathological impairments, including reproductive disturbances, which have resulted in a depressed reproductive capacity. We investigated several biochemical parameters as potential biomarkers for exposure to and effects of the contaminant load in the Baltic seals. Seals from less polluted areas were used as reference material in terms of the pollution load. In both Baltic seal populations, the levels of some biochemical parameters diverged from those in the reference seals, and some of these showed a clear correlation with the individual contaminant load. Of the potential bioindicators, we propose cytochrome P4501A activity and vitamin E levels, in blubber or plasma, as exposure biomarkers for polychlorinated biphenyls (PCBs) and dichlorodiphenyltrichloroethane (DDT) in both species. The arylhydrocarbon receptor-mediated chemical-activated luciferase gene expression (CALUX) response reflects the whole PCB and DDT burden in ringed seals. Retinyl palmitate (vitamin A) levels showed a negative correlation with the individual POP load, and is proposed as potential effect biomarkers for the depletion of the vitamin A stores. As the nutritional levels of both vitamin A and E have an impact on the vitamin levels in the seals, more information on the dietary vitamin levels is needed before any conclusions can be drawn. As the relationship between biochemical parameters and contaminants varied between the two species, species-specific characteristics has to be considered when monitoring the health status and possible toxic effects of the contaminant load in ringed and grey seals.  相似文献   

Natural hazards in Nordic Countries   总被引：1，自引：0，他引：1  

Farrokh Nadim Stig AsbjФrn Schack Pedersen Philipp Schmidt-Thome Freysteinn Sigmundsson Mats Engdahl 《《幕》》2008,31(1):176-184

Compared to many areas of the world, the human losses caused by natural hazards are smaller in Nordic countries. This is mainly due to the low population density in the exposed areas. However, the economic losses are significant and the geohazards picture varies among the countries. The predominant natural hazards in Nordic countries are floods, landslides, and, with the exception of Denmark, snow avalanche. Volcanoes and earthquakes are major geohazards in Iceland, and parts of Norway are susceptible to seismic activity. Slidetriggered tsunamis also represent a threat to parts of the coastal areas of Nordic countries and Greenland.  相似文献   

Seasonal and runoff-related changes in total organic carbon concentrations in the River Öre, Northern Sweden     

Anneli Ågren  Mats Jansson  Hans Ivarsson  Kevin Bishop  Jan Seibert 《Aquatic Sciences - Research Across Boundaries》2008,70(1):21-29

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Master of puppets: sculpting ancient worlds     

Mats E. Eriksson 《Geology Today》2014,30(3):98-104

Some extraordinary people have dedicated their lives to making art pieces out of long dead organisms. One of them is Esben Horn, founder of model shop 10 Tons Studios on the outskirts of Copenhagen, Denmark. A bona fide ‘master of puppets’, he makes jaw‐dropping replicas for museums around the world, with the utmost respect for science and organismal anatomy. Recently, our joint efforts resulted in the exhibition ‘Heavy Metal and Punk Fossils’—a novel, albeit perhaps unconventional, forum for scientific outreach.  相似文献   

Impact of isostatic land uplift and artificial drainage on oxidation of brackish-water sediments rich in metastable iron sulfide   总被引：1，自引：0，他引：1  

Anton Boman  Sören Fröjdö  Mats E. Åström 《Geochimica et cosmochimica acta》2010,74(4):1268-177

This study examines the dynamics of sulfur and trace elements (As, Co, Mo, Ni, Ti and Zn) when brackish-water sediments, unusually rich in metastable iron sulfide (probably a mixture of mackinawite and greigite), are brought into the oxidation zone by postglacial isostatic land uplift and farmland drainage. When subaqueous sediments approach the sea level, metastable iron sulfide is oxidized in the upmost layers and pyrite preserved and even accumulated concomitantly trapping Co, Ni and Zn but not As and Mo. When the land uplift has brought the sediments above sea level and natural drainage thus is initiated, the pyrite is oxidized and Co, Ni and Zn are released and transported down the profile. If this setting remained undisturbed, the slightly oxidized sediment (unripe soil) would become covered by peat and thus protected from further oxidation and metal translocation. Often these sediments are, however, artificially drained resulting in extensive oxidation and fast soil-profile development. The soil is an acid sulfate (AS) soil, characterized by low pH (<4), extensive leaching of metals and an abundance of disseminated brownish Fe(III) precipitates. We suggest that the fast soil development is due to initial oxidation of metastable iron sulfide, followed by pyrite oxidation. Drain bottom sediment, which in terms of chemistry and S-isotopes resembled that of the surfacing sea bottom strata, acted during the sampling period as a sink for metals. The abundant preservation of metastable iron sulfide below the groundwater table, even long periods after uplift above the sea level, is a puzzling feature. We suggest that it is the net result of sulfur starvation, an abundance of Fe(II) and strongly reducing conditions.  相似文献   

The slow rotation of 253 Mathilde     

Stefano Mottola  William D. Sears  Anders Erikson  Alan W. Harris  Jim W. Young  Gerhard Hahn  Mats Dahlgren  Beatrice E. A. Mueller  Bill Owen  Ricardo Gil-Hutton  Javier Licandro  M. Antonietta Barucci  Claudia Angeli  Gerhard Neukum  Claes-Ingvar Lagerkvist  J. Felix Lahulla 《Planetary and Space Science》1995,43(12)

CCD photometry of the NEAR mission fly-by target 253 Mathilde is presented. Measurements taken during 52 nights of observations, from February to June 1995, allow a rotation period of 17.406±0.010 days and a lightcurve amplitude of 0.45±0.02 mag to be determined. A B-V color index of 0.67±0.02 and a V-R of 0.35±0.02 are measured, which are compatible with C-type membership. The determination of the phase relation results in H = 10.28±0.03 and G = 0.12±0.06. Indications that the lightcurve is not strictly singly-periodic are found. A power-spectrum analysis detects a secondary frequency f₂ = 0.0322±0.0010 d⁻¹, which is interpreted as evidence for a complex rotation state.  相似文献   

俄罗斯贝加尔湖区伸展构造及与中国东部伸展构造对比   总被引：4，自引：0，他引：4  

杨巍然  隋志龙  Mats V D 《地球科学进展》2003,18(1):45-049

在晚白垩世-始新世夷平面基础上,由于断裂作用形成了贝加尔裂谷系。断裂作用最大幅度超过10 km。在裂谷系中心部位发育的断层长度最大、最深、最早,并以准对称形式向四周扩展。贝加尔裂谷系是在地幔隆起和印度-欧亚大陆碰撞双重作用下形成。贝加尔裂谷系与中国东部新生代断陷盆地和汾渭裂谷系同时形成,并有密切的成因联系。它们的形成不仅受太平洋板块的俯冲和印度-欧亚大陆碰撞的制约和影响,而且位于中国西南部的地幔流发散中心,呈扇状向太平洋区流动,可能是它们在更深层次上的共同场源基础。  相似文献