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971.
The 2011 Durban Adaptation Charter for Local Governments calls on local governments, worldwide, to institutionalise climate response, with the aim of minimising the impacts of climate change on local livelihoods and vulnerable communities. This paper, through the use of case studies, in-depth interviews and document review, assesses how three non-metropolitan municipalities in KwaZulu-Natal, a district municipality, and two local municipalities under its jurisdiction, are responding to this call. The results suggest that while the municipalities have adopted measures to institutionalise climate responses, the responses are relatively new and implementation is slow, complex and fraught with limitations and competing demands. Furthermore, there appears to be a lack of co-ordination of responses between the two levels of government, which has the potential to lead to duplication. Given the multi-scalar nature of climate change, emphasis on co-ordination and the inclusion of all municipal departments in the development and implementation of responses is necessary.  相似文献   
972.
为更系统地归纳安全氛围与安全绩效的关系,探究安全氛围、安全绩效及安全结果间的影响机制,采用Meta分析方法,通过2000—2020年54篇文献的55个独立研究样本进行定量综合分析,并进一步探讨安全氛围与安全绩效各维度间的关系,同时运用Meta二元回归探究潜在调节变量对2者间关系的调节作用。结果表明:安全氛围显著正向影响安全绩效,在高危行业中安全氛围对安全绩效影响更大;安全氛围与安全参与、安全遵守均显著正相关,且安全氛围对安全参与的影响强于对安全遵守的影响;安全氛围和安全绩效均与安全结果显著负相关,且安全绩效对安全结果的影响强于安全氛围对安全结果的影响。  相似文献   
973.
The Qinghai Lake Watershed, containing the largest saline lake in northwest of China, has suffered from severe sandy land development in recent years. This paper analyzes its daily precipitation, temperature, and wind from 1958 to 2001, and the spatial and temporal distributions of sandy land through the interpretation of remote sensing images covering four years (1977, 1987, 2000, and 2004). Results showed that since the middle of the 1960s, the daily precipitation (P) of 0<P⩽5 mm decreased, while the P>20 mm increased significantly (S<0.05) in their annual total amounts and days. The maximum daily precipitation also increased significantly. Both the maximum dry spell and the total dry spell of more than ten days had a significant upward trend. Since the beginning of the 1960s, all the extremely high, extremely low and mean temperatures increased significantly (S<0.01), at a rate of 0.1°C/10a, 0.2°C/10a, and 0.2°C/10a, respectively. The days with extremely high temperature had a significant upward trend, while the days with extremely low temperature had a significant downward trend. The Qinghai Lake was significantly shrinking (S<0.01) and provided abundant sediments for Aeolian erosion. The NNW wind prevailed in the watershed, and the largest scale wind was from the west and concentrated on the dry months. As a result, the sandy land was mainly born on the east bank of Qinghai Lake. The total sandy land area in the watershed had grown from 587.4 km2, 660.7 km2, 697.6 km2 to 805.8 km2, accordingly, its area percentage growing from 2.0%, 2.2%, 2.4% to 2.7%, respectively.  相似文献   
974.
湿地土壤在湿地环境功能中的角色与作用   总被引:9,自引:5,他引:4  
文章阐述了湿地土壤在湿地大气调节以及污染物净化方面的角色并介绍了目前湿地土壤的研究现状,分析了进一步强化湿地土壤环境功能的可能性,希望对今后湿地土壤环境功能的研究有所助益。  相似文献   
975.
This paper explores the role of risk perceptions in influencing public policy related to global warming. It solves for the optimal paths for emissions, abatement and investment in pollution-eliminating research by incorporating perceived risks into public decision making. It also compares the impact of differential risk perceptions on international collaboration on carbon abatement. Key findings are that the perception of risks related to environmental damages and technological breakthroughs plays an important role in determining the level of mitigation efforts. A high level of perceived risk of environmental damages discourages investment in pollution-eliminating research as there are few benefits from eliminating pollution after damages are realized. Other options that allow for sequestering carbon from the atmosphere may still remain viable. Another key finding is that when it comes to effort sharing between nations, differential mitigation efforts are primarily caused due to the differences in abatement technology, benefits from emissions and research capabilities. However, such differences could be accentuated or mitigated depending upon the differences in risk perception of developed and developing countries.  相似文献   
976.
河流有机碳的输送特征对区域气候的响应   总被引:1,自引:0,他引:1  
河流有机碳的输送特征与区域气候特征密切相关,气候的季节变化及空间分异、气候的异常和波动等都对河流有机碳的输送通量和性质产生显著的影响。指出降水的季节性变化直接影响河流有机碳输送通量和性质的季节性变化,不同的气候格局下河流有机碳的输送特征有较大差别,气候异常或气候波动往往使河流有机碳的输送通量和性质产生异常或波动,气候的变化直接或间接影响河流有机碳输送通量和性质的变化。  相似文献   
977.
Urea is an important source of ammonia (NH3) emissions to the atmosphere from agricultural soils. Abatement strategies are necessary in order to achieve NH3 emission targets by reducing those emissions. In this context, a field experiment was carried out on a sunflower crop in spring 2006 with the aim of evaluating the effect of the N-(n-butyl) thiophosphoric triamide (NBPT) in the mitigation of volatilized NH3 from a urea-fertilised soil. Ammonia emission was quantified, using the integrated horizontal flux (IHF) method, following application of urea with and without the urease inhibitor NBPT. Urea and a mixture of urea and NBPT (0.14%, w/w) were surface-applied at a rate of 170 kg N ha−1 to circular plots (diameter 40 m). The soil was irrigated with 10 mm of water just after the application of urea to dissolve and incorporate it into the upper layer of soil. Over the duration of the measurement period (36 days) three peaks of NH3 were observed. The first peak was associated with hydrolysis of urea after irrigation and the others with the increase of ammonia in soil solution after changes in atmospheric variables such as wind speed and rainfall. The total NH3 emission during the whole experiment was 17.3 ± 0.5 kg NH3–N ha−1 in the case of urea treated soils and 10.0 ± 2.2 kg NH3–N ha−1 where NBPT was included with the urea (10.1 and 5.9%, respectively, of the applied urea–N). The lower NH3 emissions from plots fertilised with urea + NBPT, compared with urea alone, were associated with a reduction in urease activity during the first 9 days after inhibitor application. This reduction in enzymatic activity promoted a decrease in the exchangeable NH4+ pool.  相似文献   
978.
Developing nations have tended to have been overlooked in studies of climate reporting. This study is based upon a content analysis of three daily newspapers in the Philippines to examine climate change coverage compared to reporting by Western wire services. In addition, the study draws on individualist–collectivist theory to theorize about differences in reporting between the Philippine and Western wire sources. Despite the historic influence of the American news system on Philippine journalism, the study finds that Western journalistic norms do not describe Philippine climate reporting well and that Filipino-penned articles are more likely to include the value of collectivism rather than individualism. This suggests that national cultural differences may be reflected in climate reporting.  相似文献   
979.
Evidence abounds attesting to changes in the global climate. In Ghana, climate change and climate variability have brought several exposure-sensitivities on different people and at different times. Due to the multiplicity of climate change and climate variability effects, adaptation strategies invariably could be influenced by several factors. This paper assesses the adoption of adaptation strategies in the rural northern savannah zone of Ghana as a result of climate change and variability. Using two villages each from Savelugu Nanton, West Mamprusi and Kassena Nankana East Districts, which are slightly different as case studies, the paper unearthed panoply of varied adaptation strategies in each of them including intensification of irrigation; integration of livestock production; changes in tillage practices; fertiliser application on farms; shift from agriculture to non-farm jobs; seasonal migration and purchase of drought insurance for maize. The results indicate that the relativity in adoption and utilisation of the different adaptive strategies are interlinked with geographical, social, economic, institutional and political factors and processes in the villages. The findings drum home the essentiality of location-specific planned adaptation strategies for climate change through a bottom-up approach, in order to ensure their effectiveness and sustainability.  相似文献   
980.
Several studies have been using quantified consensus within climate science as an argument to foster climate policy. Recent efforts to communicate such scientific consensus attained a high public profile but it is doubtful if they can be regarded successful. We argue that repeated efforts to shore up the scientific consensus on minimalist claims such as “humans cause global warming” are distractions from more urgent matters of knowledge, values, policy framing and public engagement. Such efforts to force policy progress through communicating scientific consensus misunderstand the relationship between scientific knowledge, publics and policymakers. More important is to focus on genuinely controversial issues within climate policy debates where expertise might play a facilitating role. Mobilizing expertise in policy debates calls for judgment, context and attention to diversity, rather than deferring to formal quantifications of narrowly scientific claims.  相似文献   
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