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21.
The U.S. Navy, whose sonars kill marine mammals, provides approximately 50% of the funds for marine mammal research worldwide. We examined six reviews of research on the effects of anthropogenic sound on marine mammals, as well as the primary papers cited in the reviews. These reviews cite references showing noise has no effect on marine mammals at an increasing frequency as their funding moves from a conservation organization to independent to partial U.S. military sources. Primary papers are 2.3 times more likely to be cited in the reviews as concluding no effect of noise if the research was militarily-funded than if not. Thus, conflict of interest may have led to a misrepresentation of the effects of noise on marine mammals in both the primary and secondary literature, and thus misinform public policy decisions. 相似文献
22.
Marketa Prusova Lucie Orlikova Marketa Hanzlova 《Central European Journal of Geosciences》2012,4(4):603-613
This paper deals with a stochastic simulation. Snow cover, representing a regionalized variable, was studied and used as an input parameter for a stochastic simulation. The first step included basic statistical analysis of individual parameters of snow, e.g. snow height. In the next step, an analysis of relationships between the snow and the geomorphological parameters (altitude, slope and aspect) was conducted. The most current methods of spatial interpolation and multifactor evaluation are based on weighted regression relationships. Primarily, the use of conditional stochastic simulation was tested in a variety of software. The main aim of this investigation is to compare selected interpolation methods with stochastic simulation, based on the development of the values and on the evaluation of the incidence of extreme events. The study shall provide users with recommendations for selecting the optimal interpolation method and its application to real data. 相似文献
23.
Ivo Baro�� Tom��? ?eh��nek Ji?�� Vo?mik V��t��zslav Musel Lucie Kondrov�� 《Landslides》2011,8(3):355-361
A large deep-seated landslide, triggered by a heavy rainfall, activated early in the morning on May 19, 2010 along the SW
slope of Gírová Mt., NE Czech Republic. The landslide occurred within a zone of pre-existing deep-seated gravitational deformation,
and it was accompanied with pronounced ground liquefying in the central and lower portion of the sliding mass. The precipitation
that triggered the landslide was about 244.6 mm that fell between May 15th and 18th with an average of 61 mm/day. No properties
or lives were lost. However, the landslide provided a good case study on triggering factors and process of liquefaction at
mountain slopes in the E Czech Republic and adjacent areas. 相似文献
24.
Mélody Prémaillon Thomas J. B. Dewez Vincent Regard Nicholas J. Rosser Sébastien Carretier Lucie Guillen 《地球表面变化过程与地形》2021,46(13):2690-2709
Sea cliff morphology and erosion rates are modulated by several factors, including rock control that reflects both lithology and rock structure. Erosion is anticipated to preferentially exploit ‘fractures’, broadly meant as any discontinuity in an otherwise continuous medium, where the rock mass is weakest. Unpicking the direct control of such fractures on the spatial and temporal pattern of erosion remains, however, challenging. To analyse how such fractures control erosion, we monitored the evolution of a 400 m-long stretch of highly structured sedimentary cliffs in Socoa, Basque Country, France. The rock is known as the Socoa flysch formation. This formation combines decimetre-thick turbidites composed of repeat triplets of medium to strong calcareous sandstone, laminated siltstones and argillaceous marls. The sequence plunges at 45° into the sea with a shore-parallel strike. The cliffs are cross-cut by two normal and reverse fault families, with 10–100 m alongshore spacing, with primary and secondary strata-bound fractures perpendicular to the bedding, which combined delimit the cliff rock mass into discrete blocks that are exploited by the erosion process. Erosion, and sometimes plucking, of such beds and blocks on the cliff face was monitored using ground-based structure-from-motion (SfM) photogrammetry, over the course of 5.7 years between 2011 and 2017. To compare with longer time change, cliff-top retreat rate was assessed using SfM-orthorectified archive aerial photographs spanning 1954–2008. We show that the 13,250 m2 cliff face released 4500 blocks exceeding 1.45 × 10−3 m3, removing a total volume of 170 m3. This equates to an average cliff erosion rate of 3.4 mm/year, which is slightly slower than the 54-year-long local cliff-top retreat (10.8 ± 1.8 mm/year). The vertical distribution of erosion reflects the height of sea water inundation, where the maximum erosion intensity occurs ca. 2 m above high spring-tide water level. Alongshore, the distribution of rockfall scars is concentrated along bed edges bounding cross-cutting faults; the extent of block detachment is controlled by secondary tectonic joints, which may extend through several beds locally sharing similar mechanical strength; and rockfall depth is always a multiple of bed thickness. Over the longer term, we explain block detachment and resultant cliff collapse as a cycle. Erosion nucleates on readily exploitable fractures but elsewhere, the sea only meets defect-free medium-strong to strong rock slabs offering few morphological features for exploitation. Structurally delimited blocks are quarried, and with sufficient time, carve semi-elliptic scars reaching progressively deeper strata to be eroded. Lateral propagation of erosion is directed along mechanical weaknesses in the bedding, and large episodic collapses affect the overhanging slabs via sliding on the weak marl beds. Collapse geometry is confined to one or several triplets of turbidite beds, but never reaches deeper into the cliff than the eroded depth at the foot. We contend that this fracture-limited model of sea-cliff erosion, inferred from the Socoa site dynamics and its peculiar sets of fractures, applies more broadly to other fractured cliff contexts, albeit with site-specific geometries. The initiation of erosion, the propagation of incremental block release and the ultimate full failure of the cliff, have each been shown to be fundamentally directly controlled by structure, which remains a vital control in understanding how cliffed coasts have changed in the past and will change in the future. 相似文献
25.
The Mt Cameroon volcano is the highest and most active volcano of the Cameroon Volcanic Line. Little geological information
is available for improving the understanding of the structure of this large volcanic system and its relationship to regional
tectonics. After reviewing the tectonic evolution of the region, the analysis of a Digital Elevation Model and results from
a field campaign dedicated to mapping geological structures in the summit area and at the SE base of Mt Cameroon are presented.
Mt Cameroon is a lava-dominated volcano with long steep (over 30°) flanks. It is elongate parallel to its well defined rift
zone. The summit plateau is bordered by 10 m high cliffs formed by summit subsidence along normal faults. Geological profiles
were measured along rivers cutting through a topographic step at the SE base of Mt Cameroon. This step is associated with
deformed Miocene sediments from the Douala basin that are overlain by volcanic products. Weak sediments of this area are deformed
by 050°–060° and 020°–030° trending asymmetrical folds verging toward the SE, and thrusts faults related to the spreading
of the volcano over its mechanically weak substratum. Combined remote sensing and field observations suggest that spreading
is accommodated by summit subsidence and flanks sliding. Both slow spreading movements and catastrophic collapses of the steep
flanks are interpreted to result from complex interactions between the growing edifice, repeated dyke intrusions, the weak
sedimentary substratum and tectonic structures. 相似文献
26.
27.
Véronique Gouy Lucie Liger Samira Ahrouch Chloé Bonnineau Nadia Carluer Arnaud Chaumot Marina Coquery Aymeric Dabrin Christelle Margoum Stéphane Pesce 《水文研究》2021,35(10):e14384
The 8-km2 Morcille catchment, which is a sub-catchment of the 150-km2 Ardières catchment in the Beaujolais region of France, is one of the first sites in Europe where research has been conducted on surface water contamination by pesticides. A consolidated hydrological and chemical dataset has been set up with data collected since 2002 on the Morcille River and since 2011 on the Ardières River. Additional data on the ecotoxicological and ecological impacts of pesticides on aquatic microbial communities and macroinvertebrates has also been recorded in both rivers since 2005. The ‘Site Atelier Ardières-Morcille Dataset’ described here combines rainfall and stream water height measurements at gauged stations with concentrations of two trace elements and nine pesticides (mainly herbicides, fungicides and some of their metabolites) in both the Ardières and Morcille rivers. All contaminant concentration data showed spatial and temporal variability in water quality associated with pesticide use and rainfall patterns. This long-term monitoring framework made it possible to estimate the persistence of two herbicides (diuron and norflurazon) after legislation banning them. It took 4 years for diuron and more than 10 years for norflurazon concentrations to fall below 0.1 μg/L. Concurrent biological data showed a gradient of impacts consistent with chemical anthropogenic pressure, and rapid recovery of phototrophic microbial communities after the diuron ban. Finally, monitoring data on pesticide transport in a grassed strip set on a slope of the Morcille catchment confirmed that vegetative filter strips can effectively reduce diuron fluxes in surface runoff (>80% abatement) and infiltration water (>70% abatement). The full dataset offers a valuable resource for the validation of hydrological models and the development of global approaches to better understand the pressure–transport–exposure–impact chain and aquatic community resilience at the small catchment scale. 相似文献
28.
DORIS applications for solid earth and atmospheric sciences 总被引：2，自引：0，他引：2
Pascal Willis Laurent Soudarin Christian Jayles Lucie Rolland 《Comptes Rendus Geoscience》2007,339(16):949-959
29.
Lucie Bláhová Pavel Babica Eliška Maršálková Blahoslav Maršálek Ludek Bláha 《洁净——土壤、空气、水》2007,35(4):348-354
The first outcomes of the national monitoring program on cyanobacteria and their toxins in the Czech Republic are reported. The concentrations of extracellular microcystins (MCs, analyzed by ELISA) in 206 water samples collected from 94 localities have been investigated. Observed MC concentrations were relatively high in comparison with the literature data, although weather conditions during the covered season (year 2004) were less favorable for the cyanobacterial water blooms. Detectable MCs (>0.125 μg/L) were found in 145 waters (70% of all samples) with a median concentration of 0.67 μg/L. The total median, including samples with no detectable MCs, was 0.26 μg/L. The seasonal trend showed an increase from July to September at most localities (maximum concentrations of about 8 μg/L and extremes up to 37 μg/L). However, a peak at the beginning of the season or continuously elevated MC concentrations were also observed at some localities. Positive correlations between increasing concentrations of MCs and the dominancy of Microcystis spp. have been observed. The survey provides the first large-scale study of the occurrence and seasonal variability of extracellular microcystins that are of particular interest for drinking water management. 相似文献
30.
Sylvie Philippe Céline Leterme Sandric Lesourd Lucie Courcot Udo Haack Jacinthe Caillaud 《Applied Geochemistry》2008
The Seine estuary possesses a heavily industrialised catchment area that contrasts significantly with that possessed by the smaller Authie estuary. For both of these northern French estuaries, Pb isotopic compositions and concentrations have been determined on specimens of Hediste diversicolor (ragworms) and on HCl leachates performed on related mudflat sediment. Three sampling campaigns were completed in 2003. As expected, the reactive Pb obtained by 1 M HCl leaching, shows higher concentrations and a more anthropogenic signature in samples from the Seine estuary than in samples from the Authie. However, neither of the two sites is free from the influence of anthropogenic Pb. Possible contaminant sources are discussed through comparisons with previously published data. For the more highly contaminated Seine estuary, most of the ragworm Pb signatures are similar to those of the sediments. In contrast, ragworms from the Authie site exhibit a higher proportion of anthropogenic Pb than the corresponding sediments. Various hypotheses are discussed to explain this significant discrepancy: (1) analytical artifacts, (2) migration of ragworm populations, (3) diet and feeding behaviour, and as the most likely explanation (4) an unsuitable leaching method for the extraction of bioavailable Pb. 相似文献