Acoustic harassment devices reduce seal interaction in the Baltic salmon-trap, net fishery   总被引：1，自引：0，他引：1  

Fjalling  Arne; Wahlberg  Magnus; Westerberg  Hakan 《ICES Journal of Marine Science》2006,63(9):1751-1758

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An Evaluation of Information Meetings as a Tool for Addressing Fear of Large Carnivores     

Maria Johansson  Jens Frank  Ole-Gunnar Støen  Anders Flykt 《社会与自然资源》2017,30(3):281-298

Managing authorities in Scandinavia arrange public information meetings when members of the public express fear because wolves or brown bears approach human settlements. This study aimed to increase the understanding of the potential effect of information meetings on self-reported fear of wolves and brown bears. In total, 198 participants completed questionnaires before and after the information meetings. Nine follow-up interviews were held 1 year later. The quantitative analyses revealed that participants who found the information credible reported a significant increase in social trust and a decrease in vulnerability and fear. The qualitative analyses pointed to the importance of information content and meta-communication, for example, nonverbal cues. It is proposed that, among participants who find the information credible, information meetings may change the appraisal of wolves and brown bears, and therefore they might prove useful as an intervention to address fear of these animals.  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   

Towards the modelling of pedestrian wind speed using high-resolution digital surface models and statistical methods     

Lars Johansson  Shiho Onomura  Fredrik Lindberg  Jonathan Seaquist 《Theoretical and Applied Climatology》2016,124(1-2):189-203

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The first use of Fulton's K for assessing and comparing the conditions of inter‐tidal fish populations          下载免费PDF全文

Chris J. Barrett  Magnus L. Johnson  Nicola J. Hall  Sue L. Hull 《Marine Ecology》2016,37(1):42-45

Fulton's K condition factor was applied, for the first time, to inter‐tidal specimens of the shanny (Lipophrys pholis) and long‐spined scorpion fish (Taurulus bubalis) from two English rocky shore and two Welsh rocky shore sites during summer 2010 and winter 2011. As both species contribute to the diet of commercial species such as cod (Gadus morhua) and near‐threatened species such as the European otter (Lutra lutra), their condition may affect that of these predators. Fulton's K found that inter‐tidal Welsh fish maintained a ‘good’ condition between seasons, whereas the inter‐tidal English fish were in a poorer condition during winter. Although condition also changed amongst the sites on each coast, further studies are needed into fish morphologies, environmental parameters, prey availabilities and abundances, and fish specimen sex and maturities.  相似文献   

Identifying landslide preconditions in Swedish quick clays—insights from integration of surface geophysical,core sample- and downhole property measurements     

Silvia?Salas-RomeroEmail author  Alireza?Malehmir  Ian?Snowball  Bryan?C.?Lougheed  Magnus?Hellqvist 《Landslides》2016,13(5):905-923

Quick-clay landslides are a serious geohazard in Canada, Norway and Sweden. Identification and mapping of quick clays are essential endeavours because the damage caused by an individual landslide can be large and costly, with potentially fatal consequences. We collected geophysical borehole and soil core data from an area prone to quick-clay landslides in southwestern Sweden. Methodologies included in situ and laboratory measurements, providing information about natural gamma radiation, sonic velocities, electrical conductivity, pH, physical grain size, elemental and mineral composition, magnetic properties, cation exchange capacity and fossil content. A stratigraphic thickness of almost 60 m enables us to study quick clays and their host environment in Sweden at unusually high resolution. Results identify the origin and location of reflections in nearby seismic lines and assign physico-chemical properties to the geological units present in the area. We show that coarse-grained layers are sandwiched between marine clays (some of which are quick clays). These layers function as a conduit for relatively fresh water that infiltrates the marine clays and chemically destabilizes them by leaching out their salts. The salinity distribution in the boreholes indicate that the groundwater movement is downwards, through the coarse-grained layer and towards the Göta river. The presence of these materials is important for the development of quick clays, although not a prerequisite. With the help of surface geophysical methods, the location of the coarse-grained layers can be known faster and more economically, which could be relevant for studying the potential for quick-clay landslide occurrence over large areas.  相似文献   

High‐grade localized metasomatic alteration of the granitic gneiss surrounding a clinopyroxene‐rich pegmatoid dyke: Söndrum stenhuggeriet,Halmstad, SW Sweden     

D. E. Harlov  A. Van Den Kerkhof  L. Johansson 《Journal of Metamorphic Geology》2014,32(4):389-416

The Söndrum stone quarry (Halmstad, SW Sweden) exposes a transition from migmatized granitic gneissic country rock into a foliated clinopyroxene‐free granitic gneiss, and then a central pegmatoid dyke dominated by clinopyroxene megacrysts. This transition zone represents a fracture‐controlled, fluid‐alteration zone that developed under conditions of 650–700 °C and 790 MPa. Mineral chemical trends in F, Cl, Fe, Ti, Mn and Y are interpreted as documenting a fluid infiltration event associated with the formation of the pegmatoid dyke. Fluid inclusions from the pegmatoid dyke are CO₂ dominant, whereas in the surrounding country rock they are dominated by H₂O‐NaCl‐CaCl₂. Fluid inclusions from the intermediate foliated clinopyroxene‐free granitic gneiss are a mixture of the two types. The pegmatoid dyke appears to have originated from a high Ca activity, Fe‐Mg enriched, fluid‐rich granitic melt with a CO₂ component, which was emplaced along a tectonic fracture in a regionally migmatized granitic gneiss in the lower crust. This was accompanied by limited partial melting of the surrounding granitic gneiss. The Ca activity of the melt was high enough to allow for the formation of clinopyroxene megacrysts as opposed to orthopyroxene. H₂O‐enriched fluids expelled from the crystallizing pegmatoid dyke, which retained the majority of the CO₂ helping to stabilize the clinopyroxene. The expelled fluids coarsened and chemically affected the surrounding country rock resulting in trends in the mineral and fluid inclusion chemistry seen today in the foliated and regional granitic gneiss.  相似文献   

CAMAM: A Miniature Laser Ablation Ionisation Mass Spectrometer and Microscope‐Camera System for In Situ Investigation of the Composition and Morphology of Extraterrestrial Materials     

Marek Tulej  Andreas Riedo  Maike B. Neuland  Stefan Meyer  Peter Wurz  Nicolas Thomas  Valentine Grimaudo  Pavel Moreno‐García  Peter Broekmann  Anna Neubeck  Magnus Ivarsson 《Geostandards and Geoanalytical Research》2014,38(4):441-466

Performance studies of a microscope‐camera system (MCS) and a laser ablation/ionisation mass spectrometer (LIMS) instrument (referred to here as a laser mass spectrometer or LMS) are presented. These two instruments were designed independently for in situ analysis of solids on planetary surfaces and will be combined to a single miniature instrument suite for in situ chemical and morphological analysis of surface materials on planetary bodies. LMS can perform sensitive chemical (elemental, isotope and molecular) analyses with spatial resolution close to micrometre‐sized grains. It allows for studies with mass resolution (M/ΔM) up to 800 in ablation mode (elemental composition) and up to 1500 in desorption mode (molecular analysis). With an effective dynamic range of at least eight orders of magnitude, sensitive and quantitative measurements can be conducted of almost all elements and isotopes with a concentration larger than a few ppb atoms. Hence, in addition to the major element composition, which is important for the determination of mineralogical constituents of surface materials, trace elements can also be measured to provide information on mineral formation processes. Highly accurate isotope ratio measurements can be used to determine in situ geochronology of sample material and for investigations of various isotope fractionation processes. MCS can conduct optical imagery of mm‐sized objects at several wavelengths with micrometre spatial resolution for the characterisation of morphological surface details and to provide insight into surface mineralogy. Furthermore, MCS can help in the selection of sample surface areas for further mass spectrometric analysis of the chemical composition. Surface auto‐fluorescence measurements and images in polarised light are additional capabilities of the MCS, to identify either fluorescing minerals or organic materials, if present on the analysed surface, for further investigation by LMS. The results obtained by investigations of NIST reference materials, amino acid films and a natural graphite sample embedded in silicate rock are presented to illustrate the performance of the instruments and their potential to deliver chemical information for mineral and organic phases in their geological context.  相似文献   

A practical ranking system to compare toxicity of anti-fouling paints     

Karlsson J  Breitholtz M  Eklund B 《Marine pollution bulletin》2006,52(12):1661-1667

The toxicity of a number of new anti-fouling paints, claimed to function by physical means and not by leakage of toxic substances, have been tested on two common organisms in the Baltic Sea, i.e., the red macro alga Ceramium tenuicorne and the copepod Nitocra spinipes. In order to compare the toxicity between the paints a ranking system was developed based on the EC₅₀- and LC₅₀-values. The results showed a wide span in toxicity with the most toxic paints ranked 160 times more toxic than the ones ranked least toxic.

Also, TBT, irgarol and diuron, which have been used as active ingredients in traditional anti-fouling paints, were used to evaluate the sensitivity of the two test organisms. The results showed that the test organisms were equally sensitive to the substances as similar organisms in earlier studies.

In conclusion, the ranking system presented in this study permits ranking and comparison of total toxicity of complex mixtures.  相似文献   

Probabilistic model for eruptions and associated flood events in the Katla caldera,Iceland     

Jonas?EliassonEmail author  Gudrun?Larsen  Magnus?Tumi Gudmundsson  Freysteinn?Sigmundsson 《Computational Geosciences》2006,10(2):179-200

Eruptions in the subglacial Katla caldera, South Iceland, release catastrophic jokulhlaups (meltwater floods). The ice surface topography divides the caldera into three drainage sectors (Ko, So and En sectors) that drain onto Myrdalssandur, Solheimasandur and Markarfljot plains, respectively. In historical times, floods from the Ko sector have been dominant, with only two recorded So events. Geological records indicate that floods from the En sector occur every 500–800 years. A probabilistic model for an eruption is formulated in general terms by a stochastic parameter that simulates a series giving the time interval in years between two consecutive events. The model also contains a Markovian matrix that controls the location of the event and thereby what watercourse is hit by the flood. A record of Katla eruptions since the 8th and the 9th century a.d., and geological information of volcanogenic floods towards the west over the last 8,000 years is used to calibrate the model. The model is then used to find the probabilities for floods from the three sectors: Ko, So and En. The simulations predict that the most probable eruption interval for the En sector and the So sector is several times smaller than the average time interval, implying infrequent periods of high activity in these sectors. A correlation is found between the magnitude of eruptions and the following time intervals. Using the statistical approach and considering this magnitude–time interval correlation, the probability of an eruption in Katla volcano is considered to be 20% within the next 10 years. This compares to a probability of 93% if only a simple average is considered. These probabilities do not take account of long-term eruption precursors and should therefore be regarded as minimum values.  相似文献