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Glenn A. Hodgkins Robert W. Dudley Thomas G. Huntington 《Journal of the American Water Resources Association》2005,41(2):403-411
ABSTRACT: High springtime river flows came earlier by one to two weeks in large parts of northern New England during the 20th Century. In this study it was hypothesized that late spring/early summer recessional flows and late summer/early fall low flows could also be occurring earlier. This could result in a longer period of low flow recession and a decrease in the magnitude of low flows. To test this hypothesis, variations over time in the magnitude and timing of low flows were analyzed. To help understand the relation between low flows and climatic variables in New England, low flows were correlated with air temperatures and precipitation. Analysis of data from 23 rural, unregulated rivers across New England indicated little evidence of consistent changes in the timing or magnitude of late summer/early fall low flows during the 20th Century. The interannual variability in the timing and magnitude of the low flows in northern New England was explained much more by the interannual variability in precipitation than by the interannual variability of air temperatures. The highest correlation between the magnitude of the low flows and air temperatures was with May through November temperatures (r =?0.37, p= 0.0017), while the highest correlation with precipitation was with July through August precipitation (r = 0.67, p > 0.0001). 相似文献
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为分析“十三五”期间(2016—2020年)我国化工和危险化学品事故发生情况,统计“十三五”期间化工和危险化学品事故数量及死亡人数,从发生月份、发生区域、行业分布等方面分析事故特征,从事故类别、事故环节、关键作业等方面分析事故原因,总结2011—2020年我国化工和危险化学品事故发展趋势,按照全国4大经济区域研究2013—2020年事故特征。结果表明:“十三五”期间我国化工和危险化学品事故数量呈下降趋势,死亡人数出现波动,总体形势较为平稳。2011—2020年化工和危险化学品事故风险向中西部转移趋势明显,东北、西部地区事故死亡率普遍高于东部地区。研究结果可为相关行业从业者及监管部门提供决策参考。 相似文献
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The northern, resource-dependent regions of Canada have long faced distinctive social, economic, and environmental challenges and vulnerabilities. However, these regions and communities increasingly find themselves in a transitional and post-productivist context – the implications of which are largely unclear. Therefore, research is needed to identify the current and emerging challenges facing such regions and how environmental governance and planning must adjust to meet these challenges. We utilise the case study of the Northeast Superior region of Ontario to identify and analyse the dynamics developing in post-productivist, resource-dependent regions and what the implications may be for environmental governance. Several key themes and issues that emerged include an increasingly pluralistic context, new regionalism and north–south tensions, First Nation initiatives and power imbalances, and northern identities which are tied to ideas of historical resource-dependence, remoteness, and intimate and complex links to the landscape, all of which inform environmental governance and sustainability debates. As a result, the Northeast Superior case provides insight into these ongoing dynamics which encompass individuals, government, industry, organisations, and the landscape, with the resultant lessons being transferable to initiatives in other northern, remote, and circumpolar regions. 相似文献
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西部大开发十五年环境效率评价及其影响因素分析 总被引:1,自引:0,他引:1
西部大开发政策实施以来,西部地区实现了快于东部和中部的经济增长。正确认识西部地区经济增长中的环境成本,评价西部地区的环境效率具有重要意义。本文运用考虑非期望产出的超效率SBM模型测算了2000—2014年西部大开发以来的环境效率。研究发现:西部地区环境效率偏低,处于相对无效状态。西部地区环境效率明显低于传统效率,经济增长付出了较高的环境代价。西部大开发以来传统效率与环境效率之间的差距呈现先扩大后缩小的"倒U"型走势变化。西部地区省份环境效率在全国排名靠后,各省份的环境效率呈现出差异化的发展态势,其中重庆和四川排名不断提升,新疆排名逐步回落,内蒙古和广西在西部地区排名相对靠前且比较稳定,云南和陕西一直处于中间水平,贵州、甘肃、青海、宁夏排名相对靠后。西部地区环境效率2000—2003年上升,2004—2010年不断下降,2010—2014年趋于平稳。西部地区环境效率低于东部地区且差距大,也低于中部地区和全国平均水平。通过收敛性检验发现,西部地区各省份间的环境效率差距呈现先缩小后扩大的趋势;西部地区与东部地区间的环境效率差距逐渐扩大,与中部地区间的环境效率差距先扩大后缩小。本文同时采用了Tobit模型进行面板回归,实证分析了西部地区环境效率的影响因素。结果表明:经济发展水平、科学技术水平、能源消费结构、环保投资力度对西部地区环境效率具有显著影响;产业结构变化和对外开放程度对西部地区环境效率影响不显著;西部地区存在环境效率的库兹涅茨曲线。 相似文献
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Morey Burnham Zhao Ma Joanna Endter‐Wada Tim Bardsley 《Journal of the American Water Resources Association》2016,52(6):1366-1384
In the Wasatch Range Metropolitan Area of Northern Utah, water management decision makers confront multiple forms of uncertainty and risk. Adapting to these uncertainties and risks is critical for maintaining the long‐term sustainability of the region's water supply. This study draws on interview data to assess the major challenges climatic and social changes pose to Utah's water future, as well as potential solutions. The study identifies the water management adaptation decision‐making space shaped by the interacting institutional, social, economic, political, and biophysical processes that enable and constrain sustainable water management. The study finds water managers and other water actors see challenges related to reallocating water, including equitable water transfers and stakeholder cooperation, addressing population growth, and locating additional water supplies, as more problematic than the challenges posed by climate change. Furthermore, there is significant disagreement between water actors over how to best adapt to both climatic and social changes. This study concludes with a discussion of the path dependencies that present challenges to adaptive water management decision making, as well as opportunities for the pursuit of a new water management paradigm based on soft‐path solutions. Such knowledge is useful for understanding the institutional and social adaptations needed for water management to successfully address future uncertainties and risks. 相似文献
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The Southern Ocean is one of the most rapidly changing ecosystems on the planet due to the effects of climate change and commercial fishing for ecologically important krill and fish. Because sea ice loss is expected to be accompanied by declines in krill and fish predators, decoupling the effects of climate and anthropogenic changes on these predator populations is crucial for ecosystem‐based management of the Southern Ocean. We reviewed research published from 2007 to 2014 that incorporated very high‐resolution satellite imagery to assess distribution, abundance, and effects of climate and other anthropogenic changes on populations of predators in polar regions. Very high‐resolution imagery has been used to study 7 species of polar animals in 13 papers, many of which provide methods through which further research can be conducted. Use of very high‐resolution imagery in the Southern Ocean can provide a broader understanding of climate and anthropogenic forces on populations and inform management and conservation recommendations. We recommend that conservation biologists continue to integrate high‐resolution remote sensing into broad‐scale biodiversity and population studies in remote areas, where it can provide much needed detail. Aplicaciones de Imágenes de Muy Alta Resolución en el Estudio y Conservación de Grandes Depredadores en el Océano Antártico 相似文献
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城郊农业区小流域土地利用结构对氮素输出的影响 总被引:9,自引:5,他引:4
以位于湖南省长沙市城郊农业区的金脱河流域为研究区域,通过解译2009年的Spot-5卫星遥感图获取了小流域的土地利用图;结合流域的DEM图,利用ArcGIS 9.3的水文、空间分析模块将流域划分为若干个子流域,分析各子流域的土地利用结构.从2009年12月~2010年11月在各子流域出口处采取水样,分析其TN、NH4+-N、NO3--N输出浓度、输出量的时空变化特征以及与土地利用结构、施肥等因素之间的关系.结果表明,流域径流氮素污染严重,其TN、NH4+-N输出浓度呈明显的季节变化特征,为冬季>春季>夏、秋季,而NO3--N的输出浓度的季节差异较小.流域内的土地利用结构对NO3--N的输出浓度起着重要的控制作用,林地、水面表现为源作用,水田、旱地、居民地为汇作用;不同的时间尺度上土地利用结构对其影响不同,年度尺度上对NO3--N输出影响最大的为旱地,春夏季为林地,秋冬季为旱地.TN、NH4+-N的输出浓度与土地利用结构的相关性较差,各形态氮素的输出量与纯氮施用量、人口数、养猪量表现为极显著正相关. 相似文献