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151.
Per Jarle Sætre 《Norsk geografisk tidsskrift. Norwegian journal of geography》2013,67(3):120-127
At the end of the 19th century geography became a mandatory subject in primary and secondary schools in Norway. Geography was seen as a useful subject that contributed to the modernization of society, but also as a subject that strengthened the national ideology. A need for better education in geography arose and consequently some authors of geography textbooks wrote about teaching geography. In order to strengthen teachers’ education, geography was taught at university level, and to develop the subject it became necessary to relate it to other subjects, especially geology. The author shows that there are several similarities between the content of geography taught in Norwegian schools in the late 19th century and geography taught in schools today. 相似文献
152.
While single pollen records are widely used in reconstructing the environment for nearby prehistoric settlements, they are less helpful when addressing large‐scale issues of variation in human settlement patterns. In order to assess the impact of vegetation change on regional prehistoric settlement and subsistence patterns in an ecotone sensitive area, we inferred the general change in main vegetation types based on palaeobotanical investigations from across northernmost Fennoscandia. Tundra vegetation was predominant during the Lateglacial and earliest parts of the Holocene. Maritime birch forests rich in ferns started to expand c. 11 000 cal. a BP and became dominant from 10 000 cal. a BP. Pine expanded from the NE of the investigation area and pine‐birch forest dominated in the inland around 8000 cal. a BP. A gradual degeneration of forest towards more open birch woodland started c. 6000 cal. a BP with the most marked change around 3500 cal. a BP. Along the northern outer coast, this eventually led to open heathland. Comparison with the archaeological setting suggests a general correlation between low forest cover and extensive mobility patterns, while widespread and varied forest cover appear to have led to a more sedentary way of life. The background for this is arguably that the forested landscapes hosted a larger diversity of resources within a shorter foraging distance, while areas and periods with low forest cover required longer travels to obtain the desired prey and materials. 相似文献
153.
Erik Gómez-Baggethun Victoria Reyes-García Per Olsson Carlos Montes 《Global Environmental Change》2012,22(3):640-650
Research in the last decade has emphasised the potential contribution of traditional ecological knowledge to cope with challenges from global environmental change. This research examines the role of traditional ecological knowledge and shared systems of beliefs in building long-term social–ecological resilience to environmental extremes. Data were collected from 13 villages of the Doñana region, southwestern Spain, through interviews, focus groups, and systematic reviews of historical archives. First, we assess adaptive practices to cope with environmental change. Then, we use historical records of religious ceremonies (1577–1956) to reconstruct collective responses to environmental extremes. Our results (1) show how environmental extremes could induce social and economic crises through declines in ecosystem services and (2) identify practices to cope with recurrent disturbance and institutional devices developed in response to environmental extremes. We conclude that traditional ecological knowledge and shared systems of beliefs can facilitate collective responses to crises and contribute to the maintenance of long-term resilience of social–ecological systems. 相似文献
154.
The interpretation protocols for defining offshore rifted margin architecture normally include seismic‐reflection analysis supplemented by refraction and/or potential field modelling to help constrain sedimentary, basement and Moho geometries at depth and/or the presence of magmatic material. Interpretation of modern high‐resolution long‐offset reflection profiles shows that significant mismatches may arise between the structural observations made from these data and the common translation of density, magnetic or velocity values into specific rock types made by geophysical models. We illustrate this problem with three examples from the Mid‐Norwegian rifted system, and discuss the implications with respect to the geological interpretation. 相似文献
155.
156.
The recently compiled Turkish strong motion database: preliminary investigation for seismological parameters 总被引:5,自引:0,他引:5
Sinan Akkar Zehra Çağnan Emrah Yenier Özgür Erdoğan M. Abdullah Sandıkkaya Polat Gülkan 《Journal of Seismology》2010,14(3):457-479
Strong motion data recorded by the Turkish national strong motion network has been compiled and processed systematically for
the first time, together with detailed geophysical and geotechnical site measurements for all of its stations. The catalog
information of 18 seismological agencies and other sources were examined to obtain reliable source, geometry, and distance
parameters for each event. The high quality digital and analog strong motion data was processed by a uniform methodology to
remove the high- and low-frequency noise. Currently, the seismological and spectral information of 4,607 strong motion records
are available for use by earth scientists and earthquake engineers. In this article, we present the fundamental features of
this database and explain our methodology in their calculation. We present several comparisons of our database with other
related studies to verify our approach during the computational stage of the seismological parameters. The results confirm
the reliability of our calculations. The database has also enabled us to derive empirical magnitude conversion relationships
to estimate moment magnitude in terms of different magnitude scales. The article ends with a discussion of the likely improvements
in the European accelerometric data through contributions from this strong motion database applicable for seismically active
shallow-crust regions. The findings of this article emphasize the necessity of global strong motion databases in Europe for
better estimation of seismic hazard in regions of similar seismotectonic environment. 相似文献
157.
Peter Rosén Hendrik Vogel Laura Cunningham Nina Reuss Daniel J. Conley Per Persson 《Journal of Paleolimnology》2010,43(2):247-259
We demonstrate the use of Fourier transform infrared spectroscopy (FTIRS) to make quantitative measures of total organic carbon
(TOC), total inorganic carbon (TIC) and biogenic silica (BSi) concentrations in sediment. FTIRS is a fast and cost-effective
technique and only small sediment samples are needed (0.01 g). Statistically significant models were developed using sediment
samples from northern Sweden and were applied to sediment records from Sweden, northeast Siberia and Macedonia. The correlation
between FTIRS-inferred values and amounts of biogeochemical constituents assessed conventionally varied between r = 0.84–0.99 for TOC, r = 0.85–0.99 for TIC, and r = 0.68–0.94 for BSi. Because FTIR spectra contain information on a large number of both inorganic and organic components,
there is great potential for FTIRS to become an important tool in paleolimnology. 相似文献
158.
Fisheries management needs to broaden its perspective to achieve sustainable resource use. Life cycle assessment (LCA) is an ISO standardized method to evaluate the environmental impacts of products using a broad and systematic approach. In this study, the outcome of a management regime promoting species-selective trawling in Swedish Nephrops trawl fisheries was studied using LCA methodology by quantifying the impacts per kilogram of landing using two different fishing methods. Demersal trawling has previously been found to be both energy intensive and destructive in terms of seafloor impact and discards. It is demonstrated that species-selective trawling fulfils management objectives, although with tradeoffs in terms of fuel consumption and associated GHG emissions. To prioritize between impacts, one must be aware of and quantify these potential tradeoffs. LCA could be an important tool for defining sustainable seafood production as it can visualize a broad range of impacts and facilitate integrated, transparent decision making in the seafood industry. It is also concluded that, with current LCA methodology, use of total discarded mass could increasingly be distinguished from potential impact by applying two new concepts: primary production requirements and threatened species affected. 相似文献
159.
Hendrik Vogel Peter Rosén Bernd Wagner Martin Melles Per Persson 《Journal of Paleolimnology》2008,40(2):689-702
Measurements of Fourier transform infrared spectroscopy (FTIRS) in the mid-infrared (MIR) region were conducted on sedimentary
records from Lake El’gygytgyn, NE Siberia, and Lake Ohrid, Albania/Macedonia. Calibration models relating FTIR spectral information
to biogeochemical property concentrations were established using partial least squares regression (PLSR). They showed good
statistical performance for total organic carbon (TOC), total nitrogen (TN), and biogenic silica (opal) in the sediment record
from Lake El’gygytgyn, and for TOC, total inorganic carbon (TIC), TN, and opal in sediments from Lake Ohrid. In both cases,
the calibration models were successfully applied for down-core analysis. The results, in combination with the small amount
of sample material needed, negligible sample pre-treatments, and low costs of analysis, demonstrate that FTIRS is a promising,
cost-effective tool that allows high-resolution paleolimnological studies. 相似文献
160.
Per Möller Grigorij Fedorov Maxim Pavlov Marit-Solveig Seidenkrantz & Charlotte Sparrenbom 《Polar research》2008,27(2):222-248
Quaternary glacial stratigraphy and relative sea-level changes reveal at least two glacial expansions over the Chelyuskin Peninsula, bordering the Kara Sea at about 77°N in the Russian Arctic, as indicated from tills interbedded with marine sediments, exposed in stratigraphic superposition, and from raised-beach sequences mapped to altitudes of at least up to ca. 80 m a.s.l. Chronological control is provided by accelerator mass spectrometry 14 C dating, electron-spin resonance and optically stimulated luminescence geochronology. Major glaciations, followed by deglaciation and marine inundation, occurred during marine oxygen isotope stages 6–5e (MIS 6–5e) and stages MIS 5d–5c. These glacial sediments overlie marine sediments of Pliocene age, which are draped by fluvial sediment of a pre-Saalian age, thereby forming palaeovalley/basin fills in the post-Cretaceous topography. Till fabrics and glacial tectonics record expansions of local ice caps exclusively, suggesting wet-based ice cap advance, followed by cold-based regional ice-sheet expansion. Local ice caps over highland sites along the perimeter of the shallow Kara Sea, including the Byrranga Mountains and the Severnaya Zemlya archipelago, appear to have repeatedly fostered initiation of a large Kara Sea ice sheet, with the exception of the Last Glacial Maximum (MIS 2), when Kara Sea ice neither impacted the Chelyuskin Peninsula nor Severnaya Zemlya, and barely touched the northern coastal areas of the Taymyr Peninsula. 相似文献