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41.
42.
The science of climate change is full of uncertainty, but the greater vulnerability of poor countries to the impacts of climate change is one aspect that is widely acknowledged. This paper adapts Dryzek's ‘components’ approach to discourse analysis to explore the media construction of climate change and development in UK ‘quality’ newspapers between 1997 and 2007. Eight discourses are identified from more than 150 articles, based on the entities recognised, assumptions about natural relationships, agents and their motives, rhetorical devices and normative judgements. They show a wide range of opinions regarding the impacts of climate change on development and the appropriate action to be taken. Discourses concerned with likely severe impacts have dominated coverage in the Guardian and the Independent since 1997, and in all four papers since 2006. Previously discourses proposing that climate change was a low development priority had formed the coverage in the Times and the Telegraph. The classification of different discourses allows an inductive, nuanced analysis of the factors influencing representation of climate change and development issues; an analysis which highlights the role of key events, individual actors, newspaper ideology and wider social and political factors. Overall the findings demonstrate media perceptions of a rising sense of an impending catastrophe for the developing world that is defenceless without the help of the West, perpetuating to an extent views of the poor as victims.  相似文献   
43.
Early Silurian cherts from the Holy Cross and Bardzkie Mountains (Poland) contain abundant microfossils morphologically resembling contemporary cyanobacteria. Most of the organic matter preserved in the cherts is highly mature and extensively degraded because of biological decomposition and progressive thermal alteration. These processes may have changed the original morphology of the deposited microbial remains, so the microfossil origin could be easily misinterpreted. The cherts were therefore examined using organic geochemical and stable isotope techniques to provide support for the presence of cyanobacterial remains. The nitrogen isotopic composition of bulk sediments and extractable organic matter ranged from +0.1‰ to ?2.2‰ and from +1.8‰ to ?1.7‰, respectively. The δ15N values are thus in good agreement with a contribution of diazotrophic cyanobacteria for both locations. Biomarkers in the Holy Cross Mts. cherts included mid-chain branched monomethyl alkanes, indicative of a cyanobacterial contribution. However, molecular fossils of a cyanobacterial origin were not detected in the Bardzkie Mts. cherts, most likely because of the greater maturity than those from the Holy Cross Mts.  相似文献   
44.
The exact nature of the interaction between hot, fast-flowing star-cluster winds and the surrounding clumpy interstellar medium (ISM) in starburst galaxies has very few observational constraints. Besides furthering our knowledge of ISM dynamics, detailed observations of ionised gas at the very roots of large-scale outflows are required to place limits on the current generation of high-resolution galactic wind models. To this end, we conduct a detailed investigation of the ionised gas environment surrounding the young star clusters in the starburst galaxy NGC1569. Using high spatial and spectral-resolution Gemini/GMOS integral-field unit observations, we accurately characterise the line-profile shapes of the optical nebular emission lines and find a ubiquitous broad (~300 km?s?1) component underlying a bright narrower component. By mapping the properties of the individual line components, we find correlations that suggest that the broad component results from powerful cluster wind–gas clump interactions. We propose a model to explain the properties of the line components and the general turbulent state of the ISM.  相似文献   
45.
We report new results for the cosmic-ray antiproton-to-proton ratio from 3 to 50 GeV at the top of the atmosphere. These results represent the first measurements, on an event-by-event basis, of mass-resolved antiprotons above 18 GeV. The results were obtained with the NMSU-WIZARD/CAPRICE98 balloon-borne magnet spectrometer equipped with a gas-RICH (Ring-Imaging Cerenkov) counter and a silicon-tungsten imaging calorimeter. The RICH detector was the first ever flown that is capable of identifying charge-one particles at energies above 5 GeV. The spectrometer was flown on 1998 May 28-29 from Fort Sumner, New Mexico. The measured p&d1;/p ratio is in agreement with a pure secondary interstellar production.  相似文献   
46.
This study introduces a new method of tracing the history of nutrient loading in coastal oceans via delta(15)N analysis of organic nitrogen preserved in the skeleton of the massive Porites coral. Four coral cores were collected in Bali, Indonesia, from reefs exposed to high levels of fertilizers in agricultural run-off, from lagoonal corals impacted by sewage, and from a reef located 30 km offshore. Skeletal delta(15)N in the agriculturally exposed coral declined from 10.7+/-0.4 per thousand in 1970-1971, when synthetic fertilizers (-0.8 per thousand+/-0.2 per thousand) were introduced to Bali, to a depleted "anthropogenic" baseline of 3.5 per thousand+/-0.4% in the mid-1990s. delta(15)N values were negatively correlated with rainfall, suggesting that marine delta(15)N lowers during flood-bourn influxes of waste fertilizers. Reef cores exposed to untreated sewage in terrestrial discharge were enriched (7.8 and 7.3+/-0.4 per thousand), while the offshore core reflected background oceanic signals (6.2+/-0.4 per thousand). delta(15)N, N concentration, and C:N systematics indicate that the N isotopic composition of skeletal organic matter was generally well preserved over 30 years. We suggest that skeletal organic delta(15)N can serve as a recorder of past nitrogen sources. In Bali, this tracer suggests that the intensification of Western style agricultural practices since 1970 are contributing to the degradation of coastal coral reefs.  相似文献   
47.
Innovations for conservation and development   总被引:10,自引:0,他引:10  
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48.
Among the conceptual problems raised by climate change is that of how to think about the future. Theories of intergenerational justice and other accounts of obligations to the future in Anglo-American philosophy tend to argue that the remote future matters morally. Where did these arguments come from? This essay explores the roots of contemporary ideas about the remote future in debates that took place among Anglophone philosophers in the 1970s.  相似文献   
49.
Multivariate analysis of physico-chemical and chemical data has enabled differentiation among groundwaters sourced from different lithological formations in the Atherton Tablelands region of north-eastern Australia. The main water resource is stored in basalt, although basement rocks such as granite and metamorphics also contain variable amounts of water. Groundwater in the basalt is mostly Mg-Ca-Na, HCO3 type, with electrical conductivities less than 300 µS/cm and pH values from 6.5 to 8.5. Some of the other groundwater is quite similar, making the identification of hydrochemical facies difficult. Groundwater samples were grouped based on the results of a principal component factor analysis of the major dissolved constituents H4SiO4, Na+, Ca2+, Mg2+ and HCO3-, as well as pH and electrical conductivity. Based on this differentiation it was possible to identify the likely host rocks of groundwaters from unidentified lithological units, define the basalt thickness and provide a better understanding of the groundwater resource. Principal component factor analysis has also been useful in identifying the likely hydrochemical processes controlling the composition of these groundwaters, including the production of weak acids in the soil layers, silicate mineral weathering, ion-exchange reactions, evapotranspiration and the leaching of ions from organic matter. Supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00254-002-0667-z.  相似文献   
50.
Direct deposition of atmospheric nitrogen to shallow coastal embayments is usually estimated, since insufficient field measurements are available. Using Waquoit Bay (Cape Cod, MA. USA) as a case study, and a recent review of literature, we determined reasonable bounds on wet and dry inputs of inorganic and organic N. Since precipitation and wind vary daily, we explored the potential of episodic events to stimulate phytoplankton blooms. Many coastal waterbodies like Waquoit Bay are small relative to their watersheds. Nevertheless, direct deposition of NH(3), NO(3)(-), and HNO(3) is significant in the loading budget. For Waquoit Bay, direct deposition was calculated to be 7-15.5 kg total N ha(-1)yr(-1), representing 70-150% of the atmospheric N reported to reach the bay via the watershed, and 20-45% of the total N reaching the bay from all land-based sources. Episodic events were estimated to deliver up to 65 mg N m(-2)day(-1), representing a phytoplankton stock of 12.3 mg Chl m(-2), an amount unlikely to stimulate dense blooms in shallow coastal waters in the northeastern United States.  相似文献   
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