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91.
Adaptation to Climate Change in Developing Countries   总被引:2,自引:0,他引:2  
Adaptation to climate change is given increasing international attention as the confidence in climate change projections is getting higher. Developing countries have specific needs for adaptation due to high vulnerabilities, and they will in this way carry a great part of the global costs of climate change although the rising atmospheric greenhouse gas concentrations are mainly the responsibility of industrialized countries. This article provides a status of climate change adaptation in developing countries. An overview of observed and projected climate change is given, and recent literature on impacts, vulnerability, and adaptation are reviewed, including the emerging focus on mainstreaming of climate change and adaptation in development plans and programs. The article also serves as an introduction to the seven research articles of this special issue on climate change adaptation in developing countries. It is concluded that although many useful steps have been taken in the direction of ensuring adequate adaptation in developing countries, much work still remains to fully understand the drivers of past adaptation efforts, the need for future adaptation, and how to mainstream climate into general development policies.  相似文献   
92.
Within a European biomonitoring programme, Italian ryegrass (Lolium multiflorum Lam.) was employed as accumulative bioindicator of airborne trace elements (As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, V, Zn) in urban agglomerations. Applying a highly standardised method, grass cultures were exposed for consecutive periods of four weeks each to ambient air at up to 100 sites in 11 cities during 2000–2002. Results of the 2001 exposure experiments revealed a clear differentiation of trace element pollution within and among local monitoring networks. Pollution was influenced particularly by traffic emissions. Especially Sb, Pb, Cr, Fe, and Cu exhibited a very uneven distribution within the municipal areas with strong accumulation in plants from traffic-exposed sites in the city centres and close to major roads, and moderate to low levels in plants exposed at suburban or rural sites. Accumulation of Ni and V was influenced by other emission sources. The biomonitoring sites located in Spanish city centres featured a much higher pollution load by trace elements than those in other cities of the network, confirming previously reported findings obtained by chemical analyses of dust deposition and aerosols. At some heavily-trafficked sites, legal thresholds for Cu, Pb, and V contents in foodstuff and animal feed were reached or even surpassed. The study confirmed that the standardised grass exposure is a useful and reliable tool to monitor and to assess environmental levels of potentially toxic compounds of particulate matter.  相似文献   
93.
The Windsor, Ontario Exposure Assessment Study evaluated the contribution of ambient air pollutants to personal and indoor exposures of adults and asthmatic children living in Windsor, Ontario, Canada. In addition, the role of personal, indoor, and outdoor air pollution exposures upon asthmatic children's respiratory health was assessed. Several active and passive sampling methods were applied, or adapted, for personal, indoor, and outdoor residential monitoring of nitrogen dioxide, volatile organic compounds, particulate matter (PM; PM-2.5 pm [PM2.5] and < or =10 microm [PM10] in aerodynamic diameter), elemental carbon, ultrafine particles, ozone, air exchange rates, allergens in settled dust, and particulate-associated metals. Participants completed five consecutive days of monitoring during the winter and summer of 2005 and 2006. During 2006, in addition to undertaking the air pollution measurements, asthmatic children completed respiratory health measurements (including peak flow meter tests and exhaled breath condensate) and tracked respiratory symptoms in a diary. Extensive quality assurance and quality control steps were implemented, including the collocation of instruments at the National Air Pollution Surveillance site operated by Environment Canada and at the Michigan Department of Environmental Quality site in Allen Park, Detroit, MI. During field sampling, duplicate and blank samples were also completed and these data are reported. In total, 50 adults and 51 asthmatic children were recruited to participate, resulting in 922 participant days of data. When comparing the methods used in the study with standard reference methods, field blanks were low and bias was acceptable, with most methods being within 20% of reference methods. Duplicates were typically within less than 10% of each other, indicating that study results can be used with confidence. This paper covers study design, recruitment, methodology, time activity diary, surveys, and quality assurance and control results for the different methods used.  相似文献   
94.
Integrated sediment multiproxy studies and modeling were used to reconstruct past changes in the Baltic Sea ecosystem. Results of natural changes over the past 6000 years in the Baltic Sea ecosystem suggest that forecasted climate warming might enhance environmental problems of the Baltic Sea. Integrated modeling and sediment proxy studies reveal increased sea surface temperatures and expanded seafloor anoxia (in deep basins) during earlier natural warm climate phases, such as the Medieval Climate Anomaly. Under future IPCC scenarios of global warming, there is likely no improvement of bottom water conditions in the Baltic Sea. Thus, the measures already designed to produce a healthier Baltic Sea are insufficient in the long term. The interactions between climate change and anthropogenic impacts on the Baltic Sea should be considered in management, implementation of policy strategies in the Baltic Sea environmental issues, and adaptation to future climate change.  相似文献   
95.
The North Water polynya (~76°N to 79°N and 70°W to 80°W) is known to be an important habitat for several species of marine mammals and sea birds. For millennia, it has provided the basis for subsistence hunting and human presence in the northernmost part of Baffin Bay. The abundance of air-breathing top predators also represents a potential source of nutrient cycling that maintains primary production. In this study, aerial surveys conducted in 2009 and 2010 were used for the first time to map the distribution and estimate the abundance of top predators during spring in the North Water. Belugas (Delphinapterus leucas) were not detected north of 77°20′N but were found along the coast of West Greenland and offshore in the middle of the North Water with an abundance estimated at 2245 (95 % CI 1811–2783). Narwhals (Monodon monoceros) were widely distributed on the eastern side of the North Water with an estimate of abundance of 7726 (3761–15 870). Walruses (Odobenus rosmarus) were found across the North Water over both shallow and deep (>500 m) water with an estimated abundance of 1499 (1077–2087). Bearded (Erignathus barbatus) and ringed seals (Phoca hispida) used the large floes of ice in the southeastern part of the North Water for hauling out. Most polar bears (Ursus maritimus) were detected in the southern part of the polynya. The abundances of bearded and ringed seals were 6016 (3322–10 893) and 9529 (5460–16 632), respectively, and that of polar bears was 60 (12–292). Three sea bird species were distributed along the Greenland coast (eiders, Somateria spp.), in leads and cracks close to the Greenland coast (little auks, Alle alle) or widely in open water (thick-billed guillemots, Uria lomvia).  相似文献   
96.
The US Forest Service’s Forest Inventory and Analysis (FIA) program collects information on trees in areas that meet its definition of forest. However, the inventory excludes trees in areas that do not meet this definition, such as those found in urban areas, in isolated patches, in areas with sparse or predominantly herbaceous vegetation, in narrow strips (e.g., shelterbelts), or in riparian areas. In the Great Plains States, little is known about the tree resource in these noninventoried, nonforest areas, and there is a great deal of concern about the potential impact of invasive pests, such as the emerald ash borer. To address this knowledge gap, FIA’s National Inventory and Monitoring Applications Center has partnered with state cooperators and others in a project called the Great Plains Initiative to design and implement an inventory of trees in nonforest areas. The goal of the inventory is to characterize the nonforest tree resource using methods compatible with those of FIA so a holistic understanding of the resource can be obtained by integrating the two surveys. The goal of this paper is to describe the process of designing and implementing the survey, including plot and sample design, and to present some example results from a reporting tool we developed.  相似文献   
97.
Volatile organic compounds (VOCs) are emitted from anthropogenic and natural (biogenic) sources into the atmosphere. Characterizing their ambient mixing ratios or concentrations is a challenge because VOCs comprise hundreds of species, and accurate measurements are difficult. Long-term hourly and daily-resolution data have been collected in the metropolitan area of Atlanta, Georgia, a major city dominated by motor vehicle emissions. A series of observations of daily, speciated C2–C10 non-methane organic compounds (NMOC) and oxygenated hydrocarbons (OVOC) in mid-town Atlanta (Jefferson Street, JST) are compared with data from three urban-suburban sites and a nearby non-urban site. Annual-average mixing ratios of NMOC and OVOC at JST declined from 1999 through 2007. Downward trends in NMOC, CO, and NOy corroborate expected emission changes as reflected in emission inventories for Atlanta’s Fulton County. Comparison of the JST NMOC composition with data from roadside and tunnel sampling reveals similarities to motor vehicle dominated samples. The JST annual average VOC-OH reactivities from 1999 to 2007 were relatively constant compared with the decline in annual-average NMOC mixing ratios. Mean reactivity at JST, in terms of concentration*kOH, was approximately 40% alkenes, 22% aromatics, 16% isoprene and 6% other biogenics, 13% C7–C10 alkanes and 3% C2-C6 alkanes, indicating that biogenic NMOCs are important but not dominant contributors to the urban reactive NMOC mix. In contrast, isoprene constituted ~50% of the VOC-OH reactivities at two non-urban sites. Ratios of 24-hour average CO/benzene, CO/isopentane, and CO/acetylene concentrations indicate that such species are relatively conserved, consistent with their low reactivity. Ratios of more-reactive to less-reactive species show diurnal variability largely consistent with expected emission patterns, transport and mixing of air, and chemical processing.  相似文献   
98.
Climate change is likely to be one of the most important factors affecting our future food security. To mitigate negative impacts, we will require our crops to be more genetically diverse. Such diversity is available in crop wild relatives (CWRs), the wild taxa relatively closely related to crops and from which diverse traits can be transferred to the crop. Conservation of such genetic resources resides within the nation where they are found; therefore, national-level conservation recommendations are fundamental to global food security. We investigate the potential impact of climate change on CWR richness in Norway. The consequences of a 1.5 and 3.0 °C temperature rise were studied for the years 2030, 2050, 2070, 2080 and then compared to the present climate. The results indicate a pattern of shifting CWR richness from the south to the north, with increases in taxa turnover and in the numbers of threatened taxa. Recommendations for in situ and ex situ conservation actions over the short and long term for the priority CWRs in Norway are presented. The methods and recommendations developed here can be applied within other nations and at regional and global levels to improve the effectiveness of conservation actions and help ensure global food security.  相似文献   
99.
100.
The Sahel has been the object of intensive international research since the drought of the early 1970s. A considerable part of the research has focused on environmental change in general and land degradation, land cover change and climate change in particular. Rich and diverse insights from many different scientific disciplines about these three domains have been put forward. One intriguing feature is that an agreement on the overall trends of environmental change does not appear to emerge: questions such as whether the Sahel is greening, cropland is encroaching on rangelands, drought persists remain contested in the scientific literature, and arguments are supported by contrasting empirical evidence. The paper explores the generic reasons behind this situation in a systematic manner. We distinguish between divergences in interpretations emerging from (1) conceptualizations, definitions and choice of indicators, (2) biases, for example, related to selection of study sites, methodological choices, measurement accuracy, perceptions among interlocutors, and selection of temporal and spatial scales of analysis. The analysis of the root causes for different interpretations suggests that differences in findings could often be considered as complementary insights rather than mutually exclusive. This will have implications for the ways in which scientific results can be expected to support regional environmental policies and contribute to knowledge production.  相似文献   
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