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931.
Cohen et al. [16] suggest that in order to explore ways to bring climate change (CC) and sustainable development (SD) research together, it is necessary to develop more heuristic tools that can involve resource users and other stakeholders. In this respect, this paper focuses on methodological development in research to study climate change impacts and regional sustainable development (RSD). It starts with an introduction of an integrated land assessment framework (ILAF) which is part of the integrated phase of the Mackenzie Basin Impact Study (MBIS) in Canada. The paper then provides some articulation on how the integrated approach was applied in the Mackenzie Basin to show implications of climate change for RSD.  相似文献   
932.
Air pollution has been identified as a serious problem throughout the world which causes tremendous loss to the crops by affecting plant growth and yield. Earlier, air pollution was restricted to urban and industrial regions. Over the last few decades, however, it has become evident that pollutants can be transported over long distances and hence their impact may be felt widely over rural areas. The present study was conducted to evaluate the impact of urban air pollution on suburban agriculture with respect to the changes in photosynthetic rate, stomatal conductance, water-use efficiency, plant height, numbers of tillers, leaves, ears and seeds, chlorophyll, carotenoid, protein, phenol, ascorbic acid, nitrogen and sulphate-sulphur contents and seed weight of pot-grown wheat plants (Triticum aestivum var. HUW 468) kept at different sites around Varanasi city receiving varying levels of pollution load. Mean concentrations of were monitored. The study clearly showed that plants are negatively affected by the ambient levels of air pollutants. Reduction in various parameters directly corresponded with the air pollution levels at different sites.  相似文献   
933.
The purpose of this study was to predict quantitative changes in evaporation from bare soils in the Mediterranean climate region of Turkey in response to the projections of a regional climate model developed in Japan (hereafter RCM). Daily RCM data for the estimation of reference evapotranspiration (ET r) and soil evaporation were obtained for the periods of 1994–2003 and 2070–2079. Potential evaporation (E p) from bare soils was calculated using the Penman–Monteith equation with a surface resistance of zero. Simulation of actual soil evaporation (E a) was carried out using Aydin model (Aydin et al., Ecological Modelling 182:91–105, 2005) combined with Aydin and Uygur (2006, A model for estimating soil water potential of bare fields. In Proceedings of the 18th International Soil Meeting (ISM) on Soils Sustaining Life on Earth, Managing Soil and Technology, Sanliurfa, 477–480pp.) model of predicting soil water potential at the top surface layer of a bare soil, after performances of Aydin model (R 2 = 94.0%) and Aydin and Uygur model (R 2 = 97.6) were tested. The latter model is based on the relations among potential soil evaporation, hydraulic diffusivity, and soil wetness, with some simplified assumptions. Input parameters of the model are simple and easily obtainable such as climatic parameters used to compute the potential soil evaporation, average diffusivity for the drying soil, and volumetric water content at field capacity. The combination of Aydin and Aydin and Uygur models appeared to be useful in estimating water potential of soils and E a from bare soils, with only a few parameters. Unlike ET r and E p projected to increase by 92 and 69 mm (equivalent to 8.0 and 7.3% increases) due to the elevated evaporative demand of the atmosphere, respectively, E a from bare soils is projected to reduce by 50 mm (equivalent to a 16.5% decrease) in response to a decrease in rainfall by 46% in the Mediterranean region of Turkey by the 2070s predicted by RCM, and consequently, to decreased soil wetness in the future.  相似文献   
934.
We have developed a new version of the MERGE model, called MERGE-ETL, to analyse the dynamics of endogenous technological learning (ETL) in the energy system. This paper describes the basic formulation of MERGE-ETL, the solving techniques used for this model and some first numerical results in the context of policies designed to mitigate global climate changes.  相似文献   
935.
The social and economic implications of atmospheric change on biodiversity need to be seen in a global context of major shifts in the conceptualization and management of our relationship with nature. Traditionally, we have conceptualized the atmosphere and the other creatures of the biosphere as separate from the human, but their quasi-autonomy is now becoming subject to more and more human management. This raises not only economic issues, but social, political, and ethical concerns that will have substantial influence on public policy. Among these are the commodification of genetic material; the privatization of traditional knowledge; and the management of information. In this broader context, the paper examines an array of current and proposed strategies of response to changes in biodiversity as a result of climatic and other stresses.  相似文献   
936.
Global climate change is likely to have a range of consequences for human health as a result of disturbance or weakening of the biosphere's natural or human-managed life support systems. The full range of potential human health impacts of global climate change is diverse and would be distributed differentially spatially and over time. Changes in the mortality toll of heatwaves and changes in the distribution of vector-borne infectious diseases may occur early. The public health consequences of sea level rise and of regional changes in agricultural productivity may not occur (or become apparent) for several decades. Vulnerability is a measure of both sensitivity to climate change and the ability to adapt in anticipation of, or in response to, its impacts. The basic modes of adaptation to climate-induced health hazards are biological, behavioural and social. Adaptation can be undertaken at the individual, community and whole-population levels. Adaptive strategies should not introduce new health hazards. Enhancement of the acknowledged public health infrastructure and intervention programmes is essential to reduce vulnerability to the health impacts of climate change. In the longer-term, fundamental improvements in the social and material conditions of life and in the reduction of inequalities within and between populations are required for sustained reduction in vulnerability to environmental health hazards.  相似文献   
937.
The issue of biological monitoring of the local consequences of anticipated global climate change is considered for the Central Negev Highlands, Israel. Epilithic lichens are suggested as biological monitors. The proposed methodology of such monitoring consists of a sampling scheme, including lichen measurement along transects on flat calcareous rocks, and construction of a trend detection index (TDI). TDI is a sum of lichen species cover with coefficients chosen so as to ensure maximum ability to detect global climate trends. Coefficients have been estimated in a study of lichens along an altitudinal gradient from 500 to 1000 m a.s.l. The gradient study demonstrated that the TDI index is performed better than other integrated indices. Recommendations on this system to monitor climate change with epilthic lichens are given. Measuring, for instance, a hundred transects in fifty plots (two transet per plot scheme) allows one to detect a climate-driven change in the epilithic lichen community corresponding to a 0.8 °C shift in annual mean temperature. Such resolution appears sufficient in view of global warming of 2.5 °C considered by the Intergovernmental Panel on Climate Change as a realistic prediction for the end of the next century.  相似文献   
938.
Our knowledge of global climate change has many uncertainties.Whether global air temperature will increase, by how much, and when,are subject to debate, but there is little doubt that troposphericconcentrations of several trace gases are increasing. While possibleincreases in the average air temperature is a product of these changes,the increases in the trace gases alone will have an effect on agriculture.Increases in the ambient concentrations of carbon dioxide are expectedto have a positive net effect on crop production. In contrast, anyincreases in the penetration of surface-level ultraviolet-B (280–320 nm)radiation, and known increases in surface ozone concentrations, areconsidered to have adverse effects on certain crops. Our presentknowledge of the joint effects on crops of elevated levels of carbondioxide, ultraviolet-B radiation and ozone, and possible alterations in airtemperature and precipitation patterns, is virtually zero. Therefore, anypredictions of the effects of global climate change on agriculture aresubject to significant uncertainties. In contrast, coupling of climatechange (only temperature and precipitation) models to crop productionhas led to a number of future scenarios. In spite of theirpresent limitations, results from these efforts can be useful in planningfor future agriculture.  相似文献   
939.
Carbon capture and storage (CCS) has received abundant federal support in the USA as an energy technology to mitigate climate change, yet its position within the energy system remains uncertain. Because media play a significant role in shaping public conversations about science and technology, we analyzed media portrayal of CCS in newspapers from four strategically selected states. We grounded the analysis in Luhmann's theory of social functions, operationalized through the socio-political evaluation of energy deployment (SPEED) framework. Coverage emphasized economic, political/legal, and technical functions and focused on benefits, rather than risks of adoption. Although news coverage connected CCS with climate change, the connection was constrained by political/legal functions. Media responses to this constraint indicate how communication across multiple social functions may influence deployment of energy technologies.  相似文献   
940.
    
To date analyses of media climate change constructions have mostly focused on coverage in western newspapers. Consideration of coverage in developing countries, and analyses of media constructions alongside local understandings of climate change are comparatively rare. This article provides an analysis of the construction of climate change on Nepalese radio and lay constructions of environment and climate change within the country. Data from a radio program and six focus groups are analyzed. Analysis of the radio program indicated that climate change was portrayed as a certain reality with national impacts caused by the actions of the West. While climate change dominated the radio headlines, in focus groups local environmental problems received far more attention. The paper aims to both inform directions for future climate change communication in Nepal and the wider research agenda.  相似文献   
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