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481.
The Hexi Inland River Basin in an arid region of northwestern China was chosen as the study area for this research. The authors define the vulnerability of an oasis social-ecological system to glacier change; select 16 indicators from natural and socioeconomic systems according to exposure, sensitivity, and adaptive capacity; and construct a vulnerability-assessment indicator system aimed at an inland river basin in the arid region of Northwestern China. Vulnerability of the oasis socialecological system affected by glacier change in the study area is evaluated by Spatial Principal Component Analysis(SPCA) under the circumstance of glacier change. The key factors affecting the vulnerability are analyzed. The vulnerability of the oasis social-ecological system in the Hexi Inland River Basin affected by glacier change is of more than medium grade, accounting for about 48.0% of the total number of counties in the study area. In terms of the spatial pattern of the vulnerability, the oasis economic belt is the most vulnerable. With the rapid development of the area's society and economy, the exposure of the system to glacial changes is significantly increased; and an increase in glacial meltwater is not enough to overcome the impact of increased exposure, which is the main reason for the high vulnerability. Based on the result of the vulnerability analysis and combined with the present industrial structure in the Hexi Inland River Basin, near-,medium-, and long-term adaptation initiatives are put forward in the article.  相似文献   
482.
ABSTRACT

In academic and policy discourse, the concept of urban resilience is proliferating. Social theorists, especially human geographers, have rightfully criticized that the underlying politics of resilience have been ignored and stress the importance of asking “resilience of what, to what, and for whom?” This paper calls for careful consideration of not just resilience for whom and what, but also where, when, and why. A three-phase process is introduced to enable these “five Ws” to be negotiated collectively and to engender critical reflection on the politics of urban resilience as plans, initiatives, and projects are conceived, discussed, and implemented. Deployed through the hypothetical case of green infrastructure in Los Angeles, the paper concludes by illustrating how resilience planning trade-offs and decisions affect outcomes over space and time, often with significant implications for equity.  相似文献   
483.
Recent climate change has brought changes to the water regime that has affected the traditional agro-pastoral production systems and livelihoods in the Upper Kaligandaki Basin of the Nepal Himalayas. Based on fieldwork and available meteorological and hydrological data, this paper examines the changing water regime and various adaptation strategies that local farmers have adopted in this cold arid region. Increasing temperature and decreasing rainfall and snowfall have resulted in a negative water balance. In this scenario, farmers have implemented six major adaptive strategies in the trans-Himalayan Upper Mustang Valley.  相似文献   
484.
The Kuroshio Extension (KE) is the key area where the water heats the atmosphere in the northwestern Pacific Ocean in winter. Previous studies show that the active eddies in the KE area can affect sea surface temperature and thus sea surface winds. The present study reviewed the progress about the influences of the eddies on local atmosphere in recent years. Analysis and comparison were made especially for the achievements from shipboard sounding data, satellite observations and numerical experiments. Based on the geostrophic adaptation theory involved in atmospheric anomalies induced by the eddies, the following new scientific deductions were suggested: Air pressure adjustment mechanism dominated in the atmospheric response to eddies under the conditions of weaker wind speed over the eddies. The influence of eddies was often limited in the atmospheric boundary layer. On the other hand, vertical mixing mechanism played a major role in the response of the atmosphere to warm (cold) eddies when air moved faster over the eddies. Surface wind speed increased (decreased) over the warm (cold) water. Significant wind convergence took place downwind the warm water, and large amount of water vapor was transported also downwind from the warm water surface. The positive feedback between water vapor condensation and rising air forced by the surface convergence provided necessary conditions for the development of strong convection in atmosphere. These deductions will be conducive to further depicting the impact of oceanic eddies on the atmosphere quantitatively.  相似文献   
485.
双壳类适应性进化遗传基础尚未有大量研究。而生活在沿海潮间带和深海环境中的双壳贝类适应性进化的分子机制更鲜有报道。我们首次测序组装了潮间带生活的偏顶蛤Modiolus modiolus的转录组序列。同时与生活在深海热液冷泉喷口的偏顶蛤Bathymodiolus platifrons进行了比较转录组分析,阐明了这两个物种在不同环境中的适应性进化机制。M. modiolusB. platifrons的转录组组装共产生182,476和156,261个转录本,N50值分别为1,769和1,545。同时注释到27,868和23,588个基因。GO富集分析表明这些基因有相似的富集模式。两物种进化分析鉴定到10,245个直系同源基因,其中26个基因受到强烈正选择(Ka/Ks>1),12个基因受到中度正选择(0.5M. modiolus的转录组组装拼接序列,同时通过比较转录组学分析阐明了其与近缘物种B. platifrons的适应性进化机制。这为两个物种后续研究提供了序列资源和研究基础。  相似文献   
486.
弹性、脆弱性和适应——IHDP三个核心概念综述   总被引:21,自引:5,他引:16  
弹性、脆弱性和适应是全球环境变化人文因素计划( IHDP) 中三个非常重要的核心概念。 由于各自学科研究传统的差异, 不同学科在使用这些概念时其含义有很大差异, 有的甚至是不可 比的。本文主要根据《Global Environmental Change》2006 年第3 期发表的IHDP 学术委员会专题 研讨会成果, 结合UNU 关于脆弱性的研究成果, 重点介绍了这三个核心概念的演变以及相互联 系等方面的最新研究进展。  相似文献   
487.
Over the last decade, hundreds of climate change adaptation projects have been funded and implemented. Despite the importance of these first-generation adaptation projects for establishing funders and implementors’ “best practices,” very little is known about how early adaptation projects have endured, to what ends, and for whom. In this article, I propose a community-based methodology for ex-post assessment of climate change adaptation projects. This methodology contributes to recognitional justice by asking the individuals and collectives tasked with sustaining adaptation initiatives to define adaptation success and what criteria for success should be assessed. I apply this subjective assessment approach in 10 communities across Ecuador that participated in an internationally funded adaptation project that concluded in 2015. My analysis draws together participatory mapping, walking interviews with local leaders, participant observation, and surveys with former project participants. The results highlight that even adaptation projects that were deemed highly successful at their closure have uncertain futures. I find that the sustainability mechanisms that were envisioned by project implementors have not functioned, and communities are shouldering the burden of reviving failing adaptation interventions. These findings highlight that the current model of episodic funding for climate change adaptation projects and evaluation processes needs to be revisited to acknowledge the long-term challenges faced by communities. This analysis also calls attention to the importance of ex-post assessment for adaptation projects and the potential of subjective assessment approaches for building more ontological and epistemological pluralism in understandings of successful climate change adaptation.  相似文献   
488.
热带地转适应运动的动力学基础   总被引:3,自引:1,他引:2  
巢纪平 《气象学报》2000,58(1):1-10
文中讨论了热带斜压大气地转适应过程中的若干动力学约束关系 ,在不考虑行星位势涡度梯度的前提下给出了三维重力惯性波的频散方程、位势涡度时间不变式。在这基础上指出由于 Taylor- Proudman定理成立 ,运动将趋于水平化。同时指出 ,在热带纬圈半地转平衡更易出现。地转适应后的运动 ,一般是水平无辐散的 ,虽然垂直运动趋于零 ,但物理场随高度仍然有变化 ,即是层结的。  相似文献   
489.
Scaling up national climate adaptation under the Paris Agreement is critical not only to reduce risk, but also to contribute to a nation’s development. Traditional adaptation assessments are aimed at evaluating adaptation to cost-effectively reduce risk and do not capture the far-reaching benefits of adaptation in the context of development and the global Sustainable Development Goals (SDGs). By grounding adaptation planning in an SDG vision, we propose and demonstrate a methodological process that for the first time allows national decision-makers to: i) quantify the adaptation that is needed to safeguard SDG target progress, and ii) evaluate strategies of stakeholder-driven adaptation options to meet those needs whilst delivering additional SDG target co-benefits. This methodological process is spatially applied to a national adaptation assessment in Ghana. In the face of the country’s risk from floods and landslides, this analysis identifies which energy and transport assets to prioritise in order to make the greatest contribution to safeguarding development progress. Three strategies (‘built’, ‘nature-based’, ‘combined SDG strategy’) were formulated through a multi-stakeholder partnership involving government, the private sector, and academia as a means to protect Ghana’s prioritised assets against climate risk. Evaluating these adaptation strategies in terms of their ability to deliver on SDG targets, we find that the combined SDG strategy maximises SDG co-benefits across 116 targets. The proposed methodological process for integrating SDG targets in adaptation assessments is transferable to other climate-vulnerable nations, and can provide decision-makers with spatially-explicit evidence for implementing sustainable adaptation in alignment with the global agendas.  相似文献   
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