The Contribution of Philosophy to Hazards Assessment and Decision Making     

Ingrid Leman Stefanovic 《Natural Hazards》2003,28(2-3):229-247

Natural hazards assessment, mitigation, research and decisionmaking in the field have not typically been associated with the discipline of philosophy. Nevertheless, there is growing awareness that epistemological issues (regarding the nature ofscientific knowledge, for instance) and ethical questions (for example, relating to responsibilitiesto future generations) can no longer be ignored. This paper explores how values and philosophicalassumptions affect the way that we formulate natural hazards research questions; the methodsthat we choose to examine natural hazards and mitigation schemes; and, ultimately, how weinterpret technical data. It concludes with the recommendation that human factors andqualitative methods of research can contribute in a meaningful way to advancing natural hazardsresearch and decision making.  相似文献   

Stabilisation of soil organic matter by interactions with minerals as revealed by mineral dissolution and oxidative degradation   总被引：4，自引：0，他引：4  

Karin Eusterhues  Cornelia Rumpel  Markus Kleber  Ingrid Kgel-Knabner 《Organic Geochemistry》2003,34(12):1591-1600

Soil organic matter is known to contain a stable fraction with an old radiocarbon age. Size and stabilisation processes leading to the formation of this old soil carbon pool are still unclear. Our study aims to differentiate old organic matter from young and labile carbon compounds in two acid forest soils (dystric cambisol, haplic podzol). To identify such fractions soil samples were exposed to oxidation with Na₂S₂O₈ and to dissolution by hydrofluoric acid (HF). A negative correlation between ¹⁴C activity and carbon release after dissolution of the mineral matrix by HF indicates a strong association of stabilised carbon compounds with the mineral phase. A negative correlation between the ¹⁴C activity and the relative proportion of carbon resistant to oxidation by Na₂S₂O₈ shows that young carbon is removed preferentially by this treatment. The fraction remaining after oxidation represents a certain stabilised, long residence time carbon pool. This old fraction comprises between 1 and 30% of the total soil organic carbon in the surface horizons, but reaches up to 80% in the sub-surface horizons. Old OC is mainly stabilised by organo-mineral associations with clay minerals and/or iron oxides, whereas intercalation in clay minerals was not found to be important.  相似文献   

Tomographic inversion using ℓ₁-norm regularization of wavelet coefficients     

Ignace Loris  Guust Nolet  Ingrid Daubechies  F. A. Dahlen 《Geophysical Journal International》2007,170(1):359-370

We propose the use of ℓ₁ regularization in a wavelet basis for the solution of linearized seismic tomography problems   A m = d   , allowing for the possibility of sharp discontinuities superimposed on a smoothly varying background. An iterative method is used to find a sparse solution m that contains no more fine-scale structure than is necessary to fit the data d to within its assigned errors.  相似文献   

Changes in diatom, pollen, and chironomid assemblages in response to a recent volcanic event in Lake Galletué (Chilean Andes)     

Roberto Urrutia  Alberto Araneda  Fabiola Cruces  Laura Torres  Luis Chirinos  Hans C. Treutler  Nathalie Fagel  Sebastien Bertrand  Ingrid Alvial  Ricardo Barra  Emmanuel Chapron 《Limnologica》2007,37(1):49-62

Several lakes in Chile are near important volcanic areas where eruption impacts can limit the quality of lacustrine sediments for reconstructing past environmental changes. In this study, we report changes in diatoms, pollen, and chironomids assemblages after a tephra deposition in Lake Galletué (Chilean Andes). A sediment core obtained from Lake Galletué (40 m water depth) was sliced in 1 cm intervals and subsamples were taken to analyze each proxy. ²¹⁰Pb and ¹³⁷Cs activities were measured to obtain the geochronology and mineralogical analyses were performed to determine the mineral composition of the tephra. Diatom species composition and productivity were modified when the lake received the tephra; Aulacoseira granulata decreased and was later replaced by Cyclotella af. glomerata. After the tephra input, Aulacoseira granulata abundance increased to pre-disturbance levels and Cyclotella af. glomerata decreased. These changes seem to suggest a momentary increase in lake nutrient levels after the tephra deposition. Chironomid assemblages also decreased in head capsules just after the tephra deposition, but the most important change was the replacement of Ablabesmyia by Parakiefferiella, probably due to the sedimentological changes produced by the input of coarse tephra grains. Furthermore, unlike other studies, chironomid assemblages in Lake Galletué did not show a decrease drastically in diversity within the tephra layer. The pollen analysis indicated that, prior to the volcanic event, the vegetal community was dominated by Nothofagus sp., Araucaria araucana, and Blechnum sp.-type. After the tephra deposition, the same taxa are dominant, indicating that the volcanic event seems not produce changes in the vegetation. Nevertheless, within the tephra layer it is possible to see an increase in Poaceae, which represent – due to the percolation process – the effect of eruption on the vegetation. According to our results, diatoms were the most sensitive proxy for describing the changes produced by tephra deposition into the aquatic ecosystem and, despite the noticeable changes in its sedimentological properties; the lake seems to have a high resilience capacity, allowing it to return to pre-tephra input conditions.  相似文献   

Distribution and sedimentation of radionuclides in the Barents Sea   总被引：1，自引：0，他引：1  

Foyn  Lars; Svaeren  Ingrid 《ICES Journal of Marine Science》1997,54(3):333-340

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Export Production in the Subarctic North Pacific over the Last 800 kyrs: No Evidence for Iron Fertilization?     

Stephanie S. Kienast  Ingrid L. Hendy  John Crusius  Tom F. Pedersen  Stephen E. Calvert 《Journal of Oceanography》2004,60(1):189-203

The subarctic North Pacific is a high nitrate-low chlorophyll (HNLC) region, where phytoplankton growth rates, especially those of diatoms, are enhanced when micronutrient Fe is added. Accordingly, it has been suggested that glacial Fe-laden dust might have increased primary production in this region. This paper reviews published palaeoceanographic records of export production over the last 800 kyrs from the open North Pacific (north of ∼35°N). We find different patterns of export production change over time in the various domains of the North Pacific (NW and NE subarctic gyres, the marginal seas and the transition zone). However, there is no compelling evidence for an overall increase in productivity during glacials in the subarctic region, challenging the paradigm that dust-born Fe fertilization of this region has contributed to the glacial draw down of atmospheric CO₂. Potential reasons for the lack of increased glacial export production include the possibility that Fe-fertilization rapidly drives the ecosystem towards limitation by another nutrient. This effect would have been exacerbated by an even more stable mixed layer compared to today. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Estimating the catching efficiency of a 2-m beam trawl for sampling epifauna by removal experiments   总被引：1，自引：0，他引：1  

Reiss  Henning; Kroncke  Ingrid; Ehrich  Siegfried 《ICES Journal of Marine Science》2006,63(8):1453-1464

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The quantifiable clinothem – types,shapes and geometric relationships in the Plio‐Pleistocene Giant Foresets Formation,Taranaki Basin,New Zealand          下载免费PDF全文

Ingrid Anell  Ivar Midtkandal 《Basin Research》2017,29(Z1):277-297

The understanding of how clinoforms develop is approached based on shape and dimensions, correlation between geometric parameters, and internal characteristics of clinothems bounded by clinoform surfaces in high‐resolution 2D seismic data from the Giant Foresets Formation, Taranaki Basin, offshore New Zealand. The study subdivides the observed clinothems to identify nine types: 1. Oblique 2. Tangential oblique 3. Tangential oblique chaotic 4. Sigmoidal symmetrical 5. Sigmoidal divergent 6. Sigmoidal chaotic 7. Asymmetrical top‐heavy 8. Asymmetrical bottom‐heavy 9. Complex. Accommodation is a dominant control on the type of clinothem that develops, whereby limited accommodation promotes clinothems with significant shelf‐edge advance and low trajectory angles, while increasing accommodation promotes higher trajectory angles and increased deposition on the shelf. Further variations in shape, slope and deposition are influenced by many factors of which sediment influx appears be a fundamental driver. Sigmoidal clinothems tend to show a strong relationship between their maximum thickness and average thickness, their overall slope and maximum foreset angle, along with a high correlation between average thickness and toe advance. This suggests that they distribute sediment in a manner that may be possible to predict and quantify. The increasing steepness of the foreset slope from bottom‐heavy to symmetrical to top‐heavy clinothems, respectively, is dominantly the result of decreasing sediment influx. The clinothems with the steepest slopes, along with chaotic clinothems, are associated with comparatively large toe advance suggesting a strong link between over‐steepened slopes and/or collapse, and processes promoting sediment deposition along the basin floor. Apart from toe advance, the two types of chaotic clinothems develop differently from each other, and from their assumed parent‐clinothem. Tangential oblique chaotic forms steepen, and shelf‐edge advance is limited, suggesting upper slope collapse. Sigmoidal chaotic clinothems have comparatively higher shelf‐edge advance, lower shelf‐edge trajectories and gentler slopes and profiles, suggesting different processes are responsible for their development and resulting shape.  相似文献   

Microbial and viral pathogens in freshwater: current research aspects studied in Germany     

Michael Seidel  Lars Jurzik  Ingrid Brettar  Manfred G. Höfle  Christian Griebler 《Environmental Earth Sciences》2016,75(20):1384

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Temporal dynamics and persistence of sponge assemblages in a Central Pacific atoll lagoon          下载免费PDF全文

Ingrid S.S Knapp  Gareth J. Williams  James J. Bell 《Marine Ecology》2016,37(5):1147-1153

Sponges are important components of coral reef fauna, although little is known of their temporal dynamics. Sponges dominate the lagoon system at Palmyra Atoll in the Central Pacific, which may not be its natural state. Here we examined the temporal variability and recruitment rates of these sponge assemblages to determine if they are stable and examined the evidence that a recent transition has occurred from a coral‐ to sponge‐dominated system. We found 24 sponge species in permanent quadrats in the lagoon between 2009 and 2011, and 11 species on our recruitment panels. The sponge assemblage composition and abundance did not vary significantly between years and appear stable. Many sponge recruits were found in both years that the panels were examined although higher rates were recorded in the second year of the study. While it seems very possible that a change to a sponge‐dominated lagoon is associated with declining environmental quality at Palmyra as a result of modifications over 70 years ago, without pre‐modification data on reef assemblage composition this remains speculative. Our observations of short‐term temporal stability in the sponge assemblages at Palmyra highlight the potential for sponge‐dominated reef states to be maintained in degraded reef environments that are seemingly unsuitable for coral survival.  相似文献