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901.
气候变化对涟水流域蓝水绿水资源的影响 总被引:1,自引:0,他引:1
利用SWAT分布式水文模型模拟分析1996~2015年过去20 a及2020~2079年未来60 a长期气候变化背景下涟水流域蓝水绿水资源的时空分布变化特征。将气候变化划分为1996~2015年、2020~2049年、2050~2079年三段气象背景时期,选用Had GEM2-AO大气模式的RCP2.6、RCP4.5、RCP6、RCP8.5四种典型浓度路径作为未来时期的气象输入条件,并细分为9种气候变化情景。运用PSO粒子群优化算法,以KGE克林效率系数为目标函数,采用湘乡站实测径流量及MOD16蒸散发数据并行校准模型参数,通过p-factor、r-factor、R2、NSE和PBIAS评价模型模拟效果和不确定性,评价结果表明校准期及验证期蓝水绿水模拟均达到可信程度。情景分析结果表明,对比1996~2015年、2020~2049年、2050~2079年三段气候背景时期,在各RCP浓度路径下蓝水均呈现了不同程度的下降趋势,大约降低了1.4%~17.3%,绿水流均表现出一定的上升趋势,约增长3.5%~12.4%,绿水蓄量则在持续降低,大致下降了7.8%~19.7%,即使将95PPU模拟不确定性范围考虑进来,绿水流的增长趋势也较为明显。因此,将绿水资源纳入涟水流域未来水资源评价体系,实现蓝水绿水综合规划管理具有实际意义。 相似文献
902.
Climate change-related impacts have the capacity to substantially influence Small Island Developing States (SIDS) in the Caribbean. Currently, many SIDS are engaged in large-scale vulnerability assessments that aim to identify, analyse, and inform solutions to mitigate climate change-related impacts. Many of these assessments, while useful, place little emphasis on the local stakeholders' perceptions of climate change. One such Caribbean community impacted by climate-related change is Providence Island in Colombia. Using a vulnerability assessment framework (Marshall, P.A. et al. 2010. A framework for social adaptation to climate change: sustaining tropical coastal communities and industries. Gland: IUCN Publication Services), researchers interviewed island residents (N = 23) about their perceptions of climate change, impacts on the local environment, and how the island community may adapt. All interviews were transcribed and analysed using a priori and open coding to identify patterns of and relationships between stakeholders' responses. Results indicate that local perceptions of climate change are linked to (1) environmental knowledge, (2) environmental awareness, attitudes, and beliefs, and (3) perceptions of risk. Implications for local adaptive strategies, education, communication, and suggestions for engagement at the local level are discussed. 相似文献
903.
秦岭南部地区地形及气候条件复杂,作为油菜主要种植区之一,研究其农业气候资源的变化特征及其对油菜的影响,可以为该区有效利用农业气候资源、合理安排农事活动提高油菜生产提供实践参考。以1960~2014年秦岭南部33个站点的逐日气象数据和近25a各省市统计年鉴资料,通过滑动平均、线性倾向估计、灰色关联分析等方法,研究秦岭南部农业气候资源的时空变化特征及对油菜产量的影响。结果表明:(1)近55a来,秦岭南部地区油菜生长季内平均气温和≥5℃积温呈上升趋势,平均速率分别为0.2、29.3℃/10 a,冻害指数、降水量、开花期降水量和相对湿度与日照时数都呈减少趋势,平均每10 a分别减少0.3、14.8 mm、1.4 mm、0.6%、32.2 h。(2)近55a来研究区油菜生长季内平均气温与≥5℃积温的多年平均空间分布都表现为由西南向东北方向递减,冻害指数的空间变化与二者相反,表明越冬期极端最低气温值在空间上由西南向东北逐渐减小;其水资源指标多年平均空间分布由南向北递减,日照时数则由西南向东北递增。(3)1960~2014年秦岭南部油菜生长季内平均气温与≥5℃积温在空间上均呈极显著的增加趋势,研究区西部变化幅度较小,东部变化幅度较大,冻害指数的空间变化趋势与二者相同;水资源与日照时数在空间上均呈极显著的减少趋势,只有少数站点表现为极显著的增加趋势,而日照时数在研究区东部变化幅度相对较大,其余区域变化幅度相对较小。总体上,平均气温和≥5℃积温高值区的变化幅度小,低值区变化幅度大,其他指标与之相反。(4)近25a来秦岭南部油菜气候产量呈不明显的上升趋势,平均速率为3.79 kg/(a·hm~2),其空间变化幅度差异大,且大部分站点的变化趋势均不显著;由关联度得作用于各区域油菜气候产量的主要影响因子存在差异。各农业气候资源指标的变化幅度越大,对油菜单产的可能影响相对较大。 相似文献
904.
采用M-K突变、小波分析、空间变异系数、经验正交函数分解法(EOF)和旋转经验正交函数分解法(REOF)等方法,对近48年来湘江流域40个测站干湿指数(Z指数)进行了分析。研究表明:湘江流域1960年代前期和1980年代为干旱期,1990年代为湿润期。1980年代末有向湿润转变趋势,2003年后又开始向干旱转变。湘江流域干湿的年际变化较小,降水相对稳定,存在3年、6年和10年和21年4个特征时间尺度,且未来几年湘江流域将仍处于干旱期。湘江流域干湿变化具有很好的主体一致性,依据空间异常类型可分为南部、中部、北部和西南部4个区域。 相似文献
905.
Mary Anne McDonald Author Vitae Hester J. Lipscomb Author Vitae Author Vitae Judith Glazner Author Vitae 《Journal of Safety Research》2009,40(1):53-61
Problem
Construction risk management is challenging.Method
We combined data on injuries, costs, and hours worked, obtained through a Rolling Owner-Controlled Insurance Program (ROCIP), with data from focus groups, interviews, and field observations, to prospectively study injuries and hazard control on a large university construction project.Results
Lost-time injury rates (1.0/200,000 hours worked) were considerably lower than reported for the industry, and there were no serious falls from height. Safety was considered in the awarding of contracts and project timeline development; hazard management was iterative. A top-down management commitment to safety was clearly communicated to, and embraced by, workers throughout the site.Discussion and Impact
A better understanding of how contracting relationships, workers' compensation, and liability insurance arrangements influence safety could shift risk management efforts from worker behaviors to a broader focus on how these programs and relationships affect incentives and disincentives for workplace safety and health. 相似文献906.
Abstract: Bioclimatic envelope models of species’ responses to climate change are used to predict how species will respond to increasing temperatures. These models are frequently based on the assumption that the northern and southern boundaries of a species’ range define its thermal niche. However, this assumption may be violated if populations are adapted to local temperature regimes and have evolved population‐specific thermal optima. Considering the prevalence of local adaptation, the assumption of a species‐wide thermal optimum may be violated for many species. We used spatially and temporally extensive demographic data for American ginseng (Panax quinquefolius L.) to examine range‐wide variation in response of population growth rate (λ) to climatic factors. Our results suggest adaptation to local temperature, but not precipitation. For each population, λ was maximized when annual temperatures were similar to site‐specific, long‐term mean temperatures. Populations from disparate climatic zones responded differently to temperature variation, and there was a linear relation between population‐level thermal optima and the 30‐year mean temperature at each site. For species that are locally adapted to temperature, bioclimatic envelope models may underestimate the extent to which increasing temperatures will decrease population growth rate. Because any directional change from long‐term mean temperatures will decrease population growth rates, all populations throughout a species’ range will be adversely affected by temperature increase, not just populations at southern and low‐elevation boundaries. Additionally, when a species’ local thermal niche is narrower than its range‐wide thermal niche, a smaller temperature increase than would be predicted by bioclimatic envelope approaches may be sufficient to decrease population growth. 相似文献
907.
《Environmental Communication: A Journal of Nature and Culture》2013,7(6):834-846
ABSTRACTClimatologists worldwide are calling for urgent action to manage climate change, but public engagement remains a significant challenge. This lack of engagement is often attributed to psychological distance: climate change is perceived as something happening far away, to other people, or in a hypothetical future. TV weathercasters are ideally situated to communicate the geographically and temporally proximate impacts of climate change and increase public engagement. This study explores the status of climate change reporting amongst weathercasters in Canada, where no such research has been conducted. The respondents suggested that many, but not all, weathercasters are engaged with climate change and interested in presenting local, climate-related content; however, their on-air climate change communication behavior is highly limited. This analysis builds on research conducted with American weather broadcaster by indicating that Canadian weathercasters share their potential as effective climate change communicators, but are highly uncertain about their capacity to support this role. 相似文献
908.
Gerald E. Galloway 《Journal of the American Water Resources Association》2011,47(3):563-570
Galloway, Gerald E., 2011. If Stationarity Is Dead, What Do We Do Now? Journal of the American Water Resources Association (JAWRA) 47(3):563‐570. DOI: 10.1111/j.1752‐1688.2011.00550.x Abstract: In January 2010, hydrologists, climatologists, engineers, and scientists met in Boulder, Colorado, to discuss the report of the death of hydrologic stationarity and the implications this might have on water resources planning and operations in the United States and abroad. For decades planners have relied on design guidance from the Interagency Advisory Committee on Water Data Bulletin 17B that was based upon the concept of stationarity. After 2½ days of discussion it became clear that the assembled community had yet to reach an agreement on whether or not to replace the assumption of stationarity with an assumption of nonstationarity or something else. Hydrologists were skeptical that data gathered to this point in the 21st Century point to any significant change in river parameters. Climatologists, on the other hand, point to climate change and the predicted shift away from current conditions to a more turbulent flood and drought filled future. Both groups are challenged to provide immediate guidance to those individuals in and outside the water community who today must commit funds and efforts on projects that will require the best estimates of future conditions. The workshop surfaced many approaches to dealing with these challenges. While there is good reason to support additional study of the death of stationarity, its implications, and new approaches, there is also a great need to provide those in the field the information they require now to plan, design, and operate today’s projects. 相似文献
909.
黑河流域生物生产量分布趋势测算研究 总被引:1,自引:0,他引:1
黑河流域地处干旱地带,水资源紧缺,天然绿洲植被迅速退化,流域的生态环境状况十分严峻。本文应用迈阿密模型以及作者提出的修正方法,对黑河流域的生物生产量进行了测算及分布趋势分析,所得结果对黑河流域以及西北干旱地区的水土资源利用和生态环境保护具有应用价值 相似文献
910.
Genserik L.L. Reniers Kristof CremerJan Buytaert 《Journal of Cleaner Production》2011,19(11):1239-1249
This article discusses an innovative approach to measure and to enhance a company’s safety culture and climate as well as its security culture and climate in one go. A safety and security culture and climate model using three dimensions (People, Procedures and Technology) is suggested to form the building blocks of the model. The Improvement Diamond for Excellence Achievement and Leadership in Safety and Security (abbreviated IDEAL S&S) model’s structure is shaped by integrating the principles of Performance Management into the well-known and much used concept of the PDCA cycle or loop of continuous improvement. This way, the model can easily be used and implemented by any organization. Furthermore, a Roadmap is provided for introducing and applying the model and the approach to test the model in a real industrial setting is explained and discussed. 相似文献