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371.
The Wenchuan earthquake in 2008 has resulted in 50% of Guangyuan city facing recovery from different extents of damages. The massive reconstruction provides a good opportunity for Guangyuan city to response to the National Council??s call for tackling climate change by developing a harmonised and low-carbon economy. However, there are many arguments about the definition of ??low carbon?? and the framework that low-carbon development should follow. Low-carbon development in an economically least developed region such as Guangyuan would provide evidence and contribute to the discussion. The paper employs CO2 emissions as an environmental indicator in scenario analysis to investigate Guangyuan??s future carbon performance in following the national call of reducing 40% of carbon intensity by 2020 and an alternative low-carbon development path. The results have demonstrated that a ??win?Cwin?? solution can be reached??keeping rapid economic growth while reducing CO2 emissions, however, only by addressing the ??correct?? determining factors. Technology improvements and production structure changes have been identified as the key determining factors to affect both carbon intensity and CO2 emissions in the future. The two factors are also interdependent. Governmental policies should give appropriate guideline to address both factors but with strong emphasis on production structure decarbonisation in order to avoid the mistake of ??polluting first and deal with the pollution later?? during the emission-intensive industrialisation processes that many western countries and China??s coastal regions have followed. 相似文献
372.
Shaun Cole Will J. Percival John A. Peacock Peder Norberg Carlton M. Baugh Carlos S. Frenk Ivan Baldry Joss Bland-Hawthorn Terry Bridges Russell Cannon Matthew Colless Chris Collins Warrick Couch Nicholas J. G. Cross Gavin Dalton Vincent R. Eke Roberto De Propris Simon P. Driver George Efstathiou Richard S. Ellis Karl Glazebrook Carole Jackson Adrian Jenkins Ofer Lahav Ian Lewis Stuart Lumsden Steve Maddox Darren Madgwick Bruce A. Peterson Will Sutherland Keith Taylor 《Monthly notices of the Royal Astronomical Society》2005,362(2):505-534
373.
The paper discusses how the current climate change debate influences the way in which development is conceptualised, negotiated
and implemented. The objective of the article is to explore some of the underlying controversies that characterise development
discourses in the context of climate change. Adaptation to climate change goes along with a significant shift in discourses
used to deal with what is normally called development. This is reflected in shifting research interests and perspectives,
from vulnerability studies to resilience thinking. However, the paper argues, this shift is problematic for the normative
contents of development and especially for a pro-poor and grass roots perspective. 相似文献
374.
Inelastic buckling of thick-walled circular conical shells under external hydrostatic pressure 总被引:1,自引:0,他引:1
The paper reports on a theoretical and an experimental study into the collapse of three thick-walled circular conical shells, which were tested to failure under external hydrostatic pressure. All three vessels failed by plastic non-symmetric bifurcation buckling. Two theoretical analyses were carried out, both based on the finite element method. One of the theoretical analyses was based on inelastic non-symmetric bifurcation buckling and the other analysis was based on plastic axisymmetric buckling. Both of these theoretical analysis and the experimental observations appeared to indicate that there is a link between plastic non-symmetric bifurcation buckling and plastic axisymmetric buckling. 相似文献
375.
James P. Terry 《Singapore journal of tropical geography》1999,20(1):86-98
This paper examines features of drainage and stream channel form and process on the mountainous volcanic island of Kadavu in the humid tropical South Pacific, and interprets the findings in relation to island environmental characteristics such as geology, regolith soils, topography, vegetation and climate. At island and sub-island scales, drainage patterns are linked to the geographical arrangement and topography of the late Cenozoic volcanoes. Stream channel and bedload characteristics demonstrate the importance of both deep saprolite weathering profiles for supplying sediment into the fluvial system, and the high energy nature of the fluvial transport regimes. Landscape chemical denudation is estimated at 50-85 mm per 1,000 years from baseflow solute concentrations converted from water conductivity readings.
Relative tectonic and sea-level stability during the late Holocene and the largely undisturbed rainforest and savanna vegetation on the island suggest that climatic factors control rates of fluvial processes on Kadavu. Streamflow records show particularly that tropical storms can have a big impact. The effects of possible increasing numbers of cyclones in the South Pacific and human vegetation disturbance on Kadavu are considered. 相似文献
Relative tectonic and sea-level stability during the late Holocene and the largely undisturbed rainforest and savanna vegetation on the island suggest that climatic factors control rates of fluvial processes on Kadavu. Streamflow records show particularly that tropical storms can have a big impact. The effects of possible increasing numbers of cyclones in the South Pacific and human vegetation disturbance on Kadavu are considered. 相似文献
376.
Terry V. Callaghan Malcolm C. Press John A. Lee David L. Robinson Clive W. Anderson 《Polar research》1999,18(2):191-197
This paper compares the responses of two contrasting Arctic ecosystems to climate change simulations: a polar semi-desert (in Svalbard) and a dwarf shrub heath (at Abisko, northern Sweden). These ecosystems are located close to the northern-and southernmost extremes of the Arctic region, respectively. Inmacts of simulated climatic changes were determined through factorial perturbation experiments, where growing season temperature, nutrient availability and water supply were manipulated. The results are compared with the impact of interannual variation in climate on the growth of a keystone moss species, Hylocomium splendens , from the wider circumpolar area. The perturbation studies revealed that current interannual variability in temperature and the temperate tolerance of many species may exceed predicted changes in mean summer temperature over the next century. Arctic ecosystems differed in their responses to environmental manipulations, with the structure of the dwarf shrub health being affected through shifts in competitive hierarchy, potentially leading to lower biodiversity, and the polar semi-desert being affected through invasion, potentially leading to higher diversity. H. splendens showed negative responses to perturbation at the sub-Arctic site, in contrast to the positive relationship between temperature and growth observed in the natural environment. This apparent discrepancy may result from: (i) artefacts arising from the perturbations, such as lower atmospheric relative humidity; (ii) non-equilibrium responses during the relatively short-term perturbation studies and/or (iii) ecotypic variation in the moss population. Thus, caution should be employed when extrapolating from perturbations studies to both longer time-scales and different ecosystems within the Arctic. 相似文献
377.
Diane I. Doser Terry H. Webb & Diane E. Maunder 《Geophysical Journal International》1999,139(3):769-794
We present the results of body waveform modelling studies for 17 earthquakes of M w ≥5.7 occurring in the South Island, New Zealand region between 1918 and 1962, including the 1929 M s = 7.8 Buller earthquake, the largest earthquake to have occurred in the South Island this century. These studies confirm the concept of slip partitioning in the northern South Island between strike-slip faulting in southwestern Marlborough and reverse and strike-slip faulting in the Buller region, but indicate that the zone of reverse faulting is quite localized. In the central South Island, all historical earthquakes appear to be associated with strike-slip faulting, although recent (post-1991) reverse faulting events suggest that slip partitioning also occurs within this region. The difference between historical and recent seismicity in the central South Island may also reflect stress readjustment occurring in response to the 1717 ad rupture along the Alpine fault. Within the Fiordland region (southwestern South Island) none of the historical earthquakes appears to have occurred along the Australian/Pacific plate interface, but rather they are associated with complex deformation of the subducting plate as well as with deformation of the upper (Pacific) plate. Two earthquakes in the Puysegur Bank region south of the South Island suggest that strike-slip deformation east of the Puysegur Trench is playing a major role in the tectonics of the region. 相似文献
378.
The selection of representative input ground motions (IGMs) is important for a proper nonlinear response time history analysis (NLRHA) of modern structures. The prevailing IGM selection procedure requires that the response spectra of selected ground motions are matched with the code-specified design spectra, while the effect of the frequency contents combination in the time domain on the multimode interactions is not considered. Ignoring the effect of the frequency contents combination in the time domain of IGMs may cause significant variations in the analysis results for selected IGMs, although they are matched to the same design spectrum. In this paper, a modal-based ground motion selection (MGMS) procedure is proposed as a supplement to spectrum matching-based IGM selection procedures for selecting proper IGMs that can sufficiently induce the multimode interactions. In the proposed procedure, three equivalent single-degree-of-freedom (ESDOF) systems are developed by pushover analysis. NLRHA is then conducted for these ESDOF systems with a set of 20 seed IGMs chosen by the spectrum-matching–based selection procedure. Finally, seven IGMs are selected from the seed IGMs for NLRHA in the full structural model. To verify MGMS, seismic demands of high-rise buildings were computed by NLRHA with seven MGMS-selected IGMs, seven IGMs with closest spectrum matching, and groups of seven randomly selected IGMs derived from three different sets of 20 seed IGMs. The computed seismic demands with MGMS-IGMs show very good agreement with the mean demands determined using the whole set of seed IGMs, while the deviation is much lesser compared with those groups of randomly selected IGMs. 相似文献
379.
Recent studies have promoted using soil phosphate analysis to detect ancient Maya sites by delimiting areas of occupation based on decomposed organic matter. Refuse associated with human activity increases organic matter around areas of ancient human habitation. Theoretically, the highest concentration of organic matter—detectable by phosphate analysis—should be directly associated with areas of refuse disposal. Thus, the objective of this study is to investigate the potential of phosphate analysis to detect residential middens in Piedras Negras, Guatemala. This paper presents the results of a sensitive, in‐field phosphate analysis method applied as a midden prospection tool in residential areas. Phosphate concentration is correlated with artifact data obtained from a total of 37 test pits excavated in areas of varying phosphate concentration in three residential sites. A positive correlation between phosphate concentration and ceramic density indicates the potential of this method in defining and orienting excavations of residential areas. © 2001 John Wiley & Sons, Inc. 相似文献
380.