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431.
为了减少小样本时间序列资料中个别异常值对气候变化趋势分析的破坏性影响,采用探索性数据分析方法之一的三组耐抗线对西藏近30年气温、云量资料进行线性趋势分析,研究了西藏地区气温和云量的变化趋势及其区域分布,并讨论了二者的相关特征。通过与传统的最小二乘法相比,表明三组耐抗线用于西藏气候变化趋势分析具有明显优势,而用最小二乘法得到的西藏气候变暖估计偏高。分析认为,西藏气候变暖主要由最低气温增高显著所致,最低气温变暖趋势在春、夏季较明显,冬季相对不明显;西藏各地增温幅度在空间分布上不一致,中、西部地区呈较强的增温趋势,东部相对较弱;西藏高原总云量和低云量总体呈减少趋势,总云量和低云量变少分别与西部和中部地区的升温之间存在显著负相关关系。 相似文献
432.
Delali B.K. Dovie 《Environment, Development and Sustainability》2002,4(1):51-67
Since the Rio conference, many countries and organisations, including the environmental movement, bilateral and multilateral institutions have endeavoured to carry out activities related to the implementation of Agenda 21. These have mostly been done with or without other outcomes of the conference. Several environmental management and sustainable development agenda have been pursued to halt the continually degrading environment. Other programmes have concentrated on outburst of economic development at the expense of the environment and the worsening poverty especially in the South. This paper therefore seeks to examine a paradigmatic shift in environmentalism, emphasising the link between agenda 21 and sustainable livelihoods. It seems though the history of the environmental movement has been forgotten after the Rio conference by the whole world. This might probably be due to complacency with the results of the UNCED conference. However, it is now obvious that clear objectives to implement the results of UNCED are almost lacking with little or no proper supervision, and further threatening the existence of mankind. The environmental movement and associated milestones have had significant impacts on the current status of the global commons. Regionally in most of southern Africa, livelihood issues are in the forefront of efforts to sustain environmental resources, and minimising proximate causes of global environmental change. 相似文献
433.
南方丘陵山地带土壤保持功能及其经济价值时空变化特征 总被引:2,自引:0,他引:2
土壤保持是生态系统提供的重要调节服务之一,在区域侵蚀控制以及生态安全的维持方面具有不可替代的作用。以全国主体生态功能区划中"两屏三带"的南方丘陵山地带为研究对象,在遥感和地理信息系统的支持下,以2000、2005和2010年3期生态系统类型数据为主要数据源,运用通用土壤流失方程(Universal Soil Loss Equation, USLE)分析了南方丘陵山地带生态系统土壤保持功能,并对其经济价值进行动态核算。结果表明:10 a间,南方丘陵山地带土壤保持总量呈上升趋势,土壤保持总量上升了76.79×107 t,森林、灌丛和农田生态系统是研究区土壤保持功能的主要贡献者,总贡献率3个年份分别为82.29%、82.59%和80.58%,不同生态系统土壤保持总量排序为森林> 灌丛> 农田> 草地> 湿地> 人工表面> 稀疏地,土壤保持能力排序为湿地> 草地> 灌丛> 森林> 农田> 人工表面> 稀疏地;10 a间,研究区土壤保持功能总经济价值增加了270.34×108元,总经济价值中以保持土壤肥力价值为主;土壤保持功能经济价值的变化以轻微增加为主,其呈现增加的区域面积和价值增幅大于经济价值减少的区域面积和价值减幅。在对该区域生态系统进行保护的基础上,因地制宜地合理增加植被盖度对防治土壤侵蚀、保持土壤养分可以起到良好效果。 相似文献
434.
435.
薛亮 《中国环境管理干部学院学报》2014,(1):11-14
特许经营作为城市水务业市场化改革的重要实现形式,经历了一个“由盛转衰”的历程。总结其中缘由,现有立法在政府管制体制、政府管制内容、招投标制度和竞争机制的构建方面存在诸多问题。完善城市水务业特许经营法律制度应“双管齐下”,着重从市场准入管制、价格管制和质量管制三方面完善相关制度设计。 相似文献
436.
Joseph A. Daraio Jerad D. Bales 《Journal of the American Water Resources Association》2014,50(5):1155-1176
Freshwater mussels (order Unionida) are a highly imperiled group of organisms that are at risk from rising stream temperatures (T). There is a need to understand the potential effects of land use (LU) and climate change (CC) on stream T and have a measure of uncertainty. We used available downscaled climate projections and LU change simulations to simulate the potential effects on average daily stream T from 2020 to 2060. Monte Carlo simulations were run, and a novel technique to analyze results was used to assess changes in hydrologic and stream T response. Simulations of daily mean T were used as input to our stochastic hourly T model. CC effects were on average two orders of magnitude greater than LU impacts on mean daily stream T. LU change affected stream T primarily in headwater streams, on average up to 2.1°C over short durations, and projected CC affected stream T, on average 2.1‐3.3°C by 2060. Daily mean flow and T ratios from Monte Carlo simulations indicated greater variance in the response of streamflow (up to 55%) to LU change than in the response of stream T (up to 9%), and greater variance in headwater stream segments compared to higher order stream segments for both streamflow and T response. Simulations indicated that combined effects of climate and LU change were not additive, suggesting a complex interaction and that forecasting long‐term stream T response requires simulating CC and LU change simultaneously. 相似文献
437.
《Environmental Communication: A Journal of Nature and Culture》2013,7(6):740-760
ABSTRACTEfforts to educate the general public about global warming and the potential policy solutions that could mitigate its effects have relied on the diffusion of facts. But, cognitive scientists have documented that psychologically distant events like global warming elicit less concern and motivation to act relative to immediate, proximal and certain events. This paper documents a quasi-experiment that tested the effect on attitudes of a television campaign that emphasized the temporally, geographically and socially proximal impacts of global warming on the ecosystems and business activity of a historically conservative area of the United States. The campaign aired on one cable provider. Subscribers of that and of competing providers in the same zip-codes were polled after the campaign. Respondents exposed to the campaign were more likely to believe that global warming is happening, to accept the scientific consensus, to be more concerned about impacts and more supportive of policy solutions. 相似文献
438.
The expectations on protected areas to deliver not only biodiversity conservation but also to provide an array of different ecosystem services rise. Sequestration and storage of carbon are promising services that protected areas may provide. This study integrates spatially explicit data on terrestrial Natura 2000 sites, soil organic carbon, and agricultural land values to estimate the potential for climate-smart conservation planning in the European Union. The objectives of this study are to analyse spatial relations between protected areas soil carbon content, and land values on the European Union's land area as well as to locate and quantify the proportion of land with high carbon and low economic value within and outside protected areas. We apply a unique interdisciplinary framework with methods ranging from analyses based on geographical information systems, agricultural economics to statistics. Findings indicate that there is a significant overlap between Natura 2000 sites and regions with high carbon content across Europe. Statistical analyses show that carbon-rich regions have significantly lower land values than other areas. Our results suggest that biodiversity protection and mitigation of climate change through conservation of soil carbon could be simultaneously achieved in Europe's protected areas and beyond. We conclude that there is a notable potential for climate-smart conservation in Europe that needs further investigation. 相似文献
439.
Groundwater is the essential resource for various uses and have a great economic importance especially in the areas like Mekong Delta, which is the home for some 18 million people and produces a half of Vietnam’s rice and contributes substantial part of the country’s gross domestic product (GDP). Sustainable use of the groundwater resource is threatened by its uncontrolled abstraction and climate change. This study assesses groundwater resources in Mekong Delta aquifer system in the context of climate change. A set of models are used for the purpose. Groundwater recharge and its spatial variation are estimated using WETSPASS model, groundwater level and storage are estimated using MODFLOW and future climatic conditions in the area are developed by downscaling the data of five General Circulation Models (GCMs) retrieved from CMIP5 data portal. Two representative concentration pathways (RCPs) scenarios (RCP4.5 and RCP8.5) are considered for projecting future conditions of groundwater resources. Results reveal that the future average annual temperature is projected to increase by 1.5 °C and 4.9 °C by the end of the 21st century under RCP4.5 and RCP8.5 scenarios, respectively. Future rainfall is projected to increase in wet season and decrease in dry season. Groundwater recharge is projected to decline in short-, medium-, and long-terms. As a result, groundwater levels and storage are also projected to decline in future. These findings may help decision-makers and stakeholders for devising sustainable groundwater management strategies in Mekong Delta. 相似文献
440.
Climate change poses new and unique challenges that threaten lives and livelihoods. Given the increasing risks and looming uncertainty of climate change, increasing attention has been directed towards adaptation, or the strategies that enable humanity to persist and thrive through climate change the best it can. Though climate change is a global problem often discussed at the national scale, urban areas are increasingly seen as having a distinct role, and distinctive motivation and capacity, for adaptation. The 12 articles in this special issue explore ways of understanding and addressing climate change impacts on urban areas. Together they reveal young but rapidly growing scholarship on how to measure, and then overcome, challenges of climate change. Two key themes emerge in this issue: 1) that we must identify and then overcome current barriers to urban adaptation and 2) frameworks/metrics are necessary to identify and track adaptation progress in urban settings. Both of these themes point to the power of indicators and other quantitative information to inform priorities and illuminate the pathway forward for adaptation. As climate change is an entirely new challenge, careful measurement that enables investment by private and public parties is necessary to provide efficient outcomes that benefit the greatest number of people. 相似文献