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141.
The growing interest in the understanding of community resilience suggests a need for improving research approaches. This article reviews methods used to date, and suggests opportunities for expanding the range and efficacy of approaches used to understand, improve, and monitor the coupled social and ecological aspects of community resilience. We explore three potential foci: research approaches that enhance understanding of community resilience; those that help to improve community resilience through the research process; and the further development of methods to guide monitoring. Most studies have relied on mixed and multistaged methods, including in-depth interviews and case studies. We comment on the wide range of approaches used, and suggest others that could be valuable. There is particular scope for greater use of cumulative studies, historical or retrospective studies, participatory methods, and systems approaches, and a need for more methods that explore the coupling of social and ecological dimensions. 相似文献
142.
The recent South Asian Tsunami has brought world-wide awareness to the effects of major disasters upon all segments of society.
Vulnerable populations such as the disabled, children, or the elderly are at particular risk in a disaster and it is vital
to consider their special needs in the design of disaster preparedness and warning systems. Additionally, tourists, recent
immigrants, and refugees face challenges when confronted with disaster in unfamiliar locations, linguistically isolated, and
in need of assimilating lifesaving information and guidance quickly when under stress. Attention to the requirements for persons
with disabilities may also benefit the greater general population which can find itself situationally disabled. Information
and Communications Technology based upon accessible design principles is part of the solution. Understanding of psychology,
ergonomics, and information design is vital, as are the unique perceptual, cognitive, physical, and linguistic challenges
that can influence the efficacy of the message. These issues are among those addressed in an ongoing project in Urakawa, Japan,
which is developing a disaster preparedness information system that meets the needs of persons with disabilities. 相似文献
143.
Richard W. Battarbee David Morley Helen Bennion Gavin L. Simpson Michael Hughes Viktorija Bauere 《Journal of Paleolimnology》2011,45(4):405-414
We describe a palaeolimnological meta-database (“LakeCores”) that includes information for lakes in Europe that have been
cored for studies of recent environmental change. Only cores with intact mud-water interfaces and good chronologies for the
last ~100–200 years are currently included. The information provided in the database includes the general characteristics
of the lakes cored, the methods used for dating and analysis and the bibliographic source of the information selected. At
present the database contains information on 1847 studies from 975 sites. Here we use the database to identify cores for which
diatom-based pH and total phosphorus (TP) reconstructions have been derived and, from an inspection of the relevant papers,
we compile summary data for the timing and extent of acidification and eutrophication of lakes across Europe. We show that
there were few cases of acidification and eutrophication in Europe prior to about 1850, and therefore that conditions prior
to 1850 can be used for reference with respect to current attempts to restore surface waters to “good ecological status”.
We also show the extent to which pH and TP levels have changed across the continent both for all lakes, and, in the case of
TP, for lakes of different types covering a range of alkalinities, altitudes, water depths and surface areas. 相似文献
144.
Kinwah Wu Roberto Soria Richard W. Hunstead Helen M. Johnston 《Monthly notices of the Royal Astronomical Society》2001,320(2):177-192
We have carried out observations of the X-ray transient GX 339−4 during its high–soft and low–hard X-ray spectral states. Our high-resolution spectroscopic observation in 1999 April suggests that the H α line has a single-peaked profile in the low–hard state as speculated in our previous paper. The He ii λ 4686 line, however, has a double-peaked profile in both the high–soft and low–hard states. This suggests that the line-emission mechanism is different in the two states. Our interpretation is that double-peaked lines are emitted from a temperature-inversion layer on the accretion disc surface when it is irradiatively heated by soft X-rays. Single-peaked lines may be emitted from outflow/wind matter driven by hard X-ray heating. We have constructed a simple plane-parallel model and we use it to illustrate that a temperature-inversion layer can be formed at the disc surface under X-ray illumination. We also discuss the conditions required for the formation of temperature inversion and line emission. Based on the velocity separations measured for the double-peaked lines in the high–soft state, we propose that GX 339−4 is a low-inclination binary system. The orbital inclination is about 15° if the orbital period is 14.8 h. 相似文献
145.
In this paper theB- andV-light curves of the eclipsing binary BW Draconis made at Kryonerion Station of the National Observatory of Athens during 1980 and 1981 are presented. 相似文献
146.
147.
Brian Sauser Clifton Baldwin Saba Pourreza Wesley Randall David Nowicki 《Natural Hazards》2018,90(1):79-99
Access to government funding is one of the most effective ways to enhance the resilience for small- and medium-sized enterprises (SME) community after a disaster. Along these lines, a major focus of SME resiliency research has been on examining factors needed to keep an SME open after a disaster. This makes sense as SMEs are critical to community recovery. It seems logical that the severity of a disaster would indicate the impact to a community. Using a systems thinking methodology, we developed a hypothesis that this correlation of severity to impact breaks down over time, causing the community to quickly spiral into trouble. This paper presents an agent-based model to test our hypothesis. The results indicate the impact to a community becomes much more extreme after a threshold or “tipping point” is crossed. 相似文献
148.
Maria Kakavas Konstantinos G. Nikolakopoulos Aggeliki Kyriou Helen Zagana 《Arabian Journal of Geosciences》2018,11(14):388
The purpose of this work is to present the detection and qualification of natural karst depressions in southern Ksiromero, SW Aitoloakarnania Prefecture, Western Greece, by the use of freely available digital surface model (DSM) data in line with the geographical information systems—GIS. The study area is a part of the Ionian geotectonic zone whose geological background consists of the Triassic evaporates and Triassic carbonate breccias. The after-Triassic carbonate series, which consist of the Jurassic limestones, the Cretaceous limestones and the Eocene limestones, are also presented in the study area. Several DSMs such as ASTER GDEM, SRTM DEM, ALOS Global DSM, and a DSM generated from Sentinel-1 data were evaluated so as to be used for the automatic karst detection. Furthermore, a karst detection procedure applied on DSMs was performed with the aid of analogue and digital air photos. Additionally, the aforementioned procedure was applied also on DEM with the aid of digitized contours referring to topographic maps characterized by a scale of 1/50,000. All the detected features have been also validated via in situ observations. Finally, all DSMs presented herein are characterized by similar percentage of success in terms of automatic karst detection, regardless their spatial resolution and height accuracy. Their rate varies from 66 to 73%. 相似文献
149.
Clementine Chirol Kate L. Spencer Simon J. Carr Iris Möller Ben Evans Jason Lynch Helen Brooks Katherine R. Royse 《地球表面变化过程与地形》2021,46(11):2279-2297
The vulnerability of saltmarshes to lateral erosion at their margin depends on the local biogeomorphological properties of the substrate. In particular, the 3D architecture of pore and root systems is expected to influence shear strength, with repercussions for the wider-scale stability of saltmarshes. We apply X-ray computed microtomography (μCT) to visualize and quantify subsurface structures in two UK saltmarshes at Tillingham Farm, Essex (silt/clay rich substrate) and Warton Sands (sand-rich substrate), with four types of ground cover: bare ground, Spartina spp, Salicornia spp and Puccinellia spp. We extracted μCT structural parameters that characterize pore and root morphologies at each station, and compared them with field measurements of shear strength using a principal component analysis and correlation tests. The 3D volumes show that species-dependent variations in root structures, plant colonization events and bioturbation activity control the morphology of macropores, while sediment cohesivity determines the structural stability and persistence of these pore structures over time, even after the vegetation has died. Areas of high porosity and high mean pore thickness were correlated to lower values of shear strength, especially at Tillingham Farm, where well-connected vertical systems of macropores were associated with current or previous colonization by Spartina spp. However, while well-connected systems of macropores may lower the local deformation threshold of the sediment, they also encourage drainage, promote vegetation growth and reduce the marsh vulnerability to hydrodynamic forces. The highest values of shear strength at both sites were found under Puccinellia spp, and were associated with a high density of mesh-like root structures that bind the sediment and resist deformation. Future studies of marsh stability should ideally consider time series of vegetation cover, especially in silt/clay-dominated saltmarshes, in order to consider the potential effect of preserved buried networks of macropores on water circulation, marsh functioning and cliff-face erosion. 相似文献
150.
Don Aldiss Helen Burke Barrie Chacksfield Richard Bingley Norman Teferle Simon Williams David Blackman Richard Burren Nigel Press 《Proceedings of the Geologists' Association. Geologists' Association》2014
Long term planning for flood risk management in coastal areas requires timely and reliable information on changes in land and sea levels. A high resolution map of current changes in land levels in the London and Thames estuary area has been generated by satellite-based persistent scatterer interferometry (PSI), aligned to absolute gravity (AG) and global positioning system (GPS) measurements. This map has been qualitatively validated by geological interpretation, which demonstrates a variety of controlling influences on the rates of land level change, ranging from near-surface to deep-seated mechanisms and from less than a decade to more than 100,000 years’ duration. 相似文献