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801.
We review the available data that can be used to assess the potential impact of climate change on vegetation, and we use central Spitsbergen, Svalbard, as a model location for the High Arctic. We used two sources of information: recent and short-term historical records, which enable assessment on scales of particular plant communities and the landscape over a period of decades, and palynological and macrofossil analyses, which enable assessment on time scales of hundreds and thousands of years and on the spatial scale of the landscape. Both of these substitutes for standardized monitoring revealed stability of vegetation, which is probably attributable to the harsh conditions and the distance of the area from sources of diaspores of potential new incomers. The only evident recent vegetation changes related to climate change are associated with succession after glacial retreats. By establishing a network of permanent plots, researchers will be able to monitor immigration of new species from diversity 'hot spots' and from an abandoned settlement nearby. This will greatly enhance our ability to understand the effects of climate change on vegetation in the High Arctic. 相似文献
802.
Climate change incurs costs, but government adaptation budgets are limited. Beyond a certain point, individuals must bear
the costs or adapt to new circumstances, creating political-economic tipping points that we explore in three examples. First,
many Alaska Native villages are threatened by erosion, but relocation is expensive. To date, critically threatened villages
have not yet been relocated, suggesting that we may already have reached a political-economic tipping point. Second, forest
fires shape landscape and ecological characteristics in interior Alaska. Climate-driven changes in fire regime require increased
fire-fighting resources to maintain current patterns of vegetation and land use, but these resources appear to be less and
less available, indicating an approaching tipping point. Third, rapid sea level rise, for example from accelerated melting
of the Greenland ice sheet, will create a choice between protection and abandonment for coastal regions throughout the world,
a potential global tipping point comparable to those now faced by Arctic communities. The examples illustrate the basic idea
that if costs of response increase more quickly than available resources, then society has fewer and fewer options as time
passes. 相似文献
803.
Global warming is breeding social conflict: The subtle impact of climate change threat on authoritarian tendencies 总被引:1,自引:0,他引:1
Immo Fritsche J. Christopher CohrsThomas Kessler Judith Bauer 《Journal of environmental psychology》2012,32(1):1-10
Climate change can increase societies’ propensity to conflict by changes in socio-structural conditions (e.g., resource scarcity, migration). We propose an additional, subtle, and general effect of climate change threat via increases in authoritarian attitudes. Three studies in Germany and the UK support this suggestion. Reminding participants of the adverse consequences climate change may have for their country increased the derogation of societal groups that may threaten the collective (e.g., criminals) as well as general authoritarian attitudes. Salient climate change threats also led to system justification and approval of system supporting groups (e.g., judges) in those people who were highly identified with their nation. We discuss the implications of these findings for the explanation of authoritarian attitudes and the question of how societies may cope with the subtle social psychological effects of climate change. 相似文献
804.
805.
Ernstson H van der Leeuw SE Redman CL Meffert DJ Davis G Alfsen C Elmqvist T 《Ambio》2010,39(8):531-545
Urbanization is a global multidimensional process paired with increasing uncertainty due to climate change, migration of people,
and changes in the capacity to sustain ecosystem services. This article lays a foundation for discussing transitions in urban
governance, which enable cities to navigate change, build capacity to withstand shocks, and use experimentation and innovation
in face of uncertainty. Using the three concrete case cities—New Orleans, Cape Town, and Phoenix—the article analyzes thresholds
and cross-scale interactions, and expands the scale at which urban resilience has been discussed by integrating the idea from
geography that cities form part of “system of cities” (i.e., they cannot be seen as single entities). Based on this, the article
argues that urban governance need to harness social networks of urban innovation to sustain ecosystem services, while nurturing
discourses that situate the city as part of regional ecosystems. The article broadens the discussion on urban resilience while
challenging resilience theory when addressing human-dominated ecosystems. Practical examples of harnessing urban innovation
are presented, paired with an agenda for research and policy. 相似文献
806.
Several monitoring programs have been set up to assess effects of atmospheric deposition on forest ecosystems. The aim of the present study was to evaluate effects on the understorey vegetation, based on the first round of a regional (the Netherlands) and a European forest monitoring program. A multivariate statistical analysis showed surprisingly similar results for both data sets; the vegetation appeared to be largely determined by the ‘traditional’ factors soil, climate, and tree species, but there was a small but statistically significant effect of atmospheric deposition. The effects of deposition include a slight shift towards nitrophytic species at high N deposition in the European network, and towards acidophytic species at high S-deposition in the Dutch network. The relatively small effect of atmospheric deposition is understandable in view of the very large natural variation in environmental conditions. Time series of both vegetation and environment are needed to assess deposition effects in detail. 相似文献
807.
根据群落的不同退化演替状况和物种组成情况,随机选取19个位于锡林郭勒高原和呼伦贝尔高原的调查样地,进行典型草原健康评价和群落退化分级研究。结果表明,处在不同退化演替阶段的草原中的群落的优势种类型、活力和恢复力指数均存在很大差异,活力和恢复力指数不存在明显的相关性,这可能是由于活力指数表现的是植物的地上生物量,而恢复力指数表现的是植物的株/丛数,在株/丛数很多的情况下生物量可能很小;草原群落地上总生物量受放牧强度、刈割程度、围封时间、围封前群落状态和区域降水等因素的综合作用,使得各调查样地群落的活力指数差异显著;以中国科学院草原生态系统定位研究站1981年设置的围封的羊草+大针茅草原当时的状态作为参照系统,评价了呼伦贝尔高原和锡林郭勒高原典型草原的健康状况,并对其退化程度进行了量化分级,可为草原管理、植被恢复重建和生态系统健康评价提供参考。 相似文献
808.
Madhu Rao Saw Htun Steven G. Platt Robert Tizard Colin Poole Than Myint James E. M. Watson 《Ambio》2013,42(7):789-804
High levels of species richness and endemism make Myanmar a regional priority for conservation. However, decades of economic and political sanctions have resulted in low conservation investment to effectively tackle threats to biodiversity. Recent sweeping political reforms have placed Myanmar on the fast track to economic development—the expectation is increased economic investments focused on the exploitation of the country’s rich, and relatively intact, natural resources. Within a context of weak regulatory capacity and inadequate environmental safeguards, rapid economic development is likely to have far-reaching negative implications for already threatened biodiversity and natural-resource-dependent human communities. Climate change will further exacerbate prevailing threats given Myanmar’s high exposure and vulnerability. The aim of this review is to examine the implications of increased economic growth and a changing climate within the larger context of biodiversity conservation in Myanmar. We summarize conservation challenges, assess direct climatological impacts on biodiversity and conclude with recommendations for long-term adaptation approaches for biodiversity conservation. 相似文献
809.
Sally Rangecroft Stephan Harrison Karen Anderson John Magrath Ana Paola Castel Paula Pacheco 《Ambio》2013,42(7):852-863
Climate change is projected to have a strongly negative effect on water supplies in the arid mountains of South America, significantly impacting millions of people. As one of the poorest countries in the region, Bolivia is particularly vulnerable to such changes due to its limited capacity to adapt. Water security is threatened further by glacial recession with Bolivian glaciers losing nearly half their ice mass over the past 50 years raising serious water management concerns. This review examines current trends in water availability and glacier melt in the Bolivian Andes, assesses the driving factors of reduced water availability and identifies key gaps in our knowledge of the Andean cryosphere. The lack of research regarding permafrost water sources in the Bolivian Andes is addressed, with focus on the potential contribution to mountain water supplies provided by rock glaciers. 相似文献
810.
A number of recent studies have suggested that black carbon (BC), the light-absorbing fraction of soot, is next to CO2 one of the strongest contributors to the global climate change. BC heats the air, darkens the snow and ice surfaces and could contribute to the melting of Arctic ice, snowpacks, and glaciers. Although soot is the oldest known pollutant its importance in climate modification has only been recently recognized. In this article, we trace the historical developments over about three decades that changed the view of the role of BC in the environment, from a pollutant of marginal importance to one of the main climate change agents. We also discuss some of the reasons for the initial lack of interest in BC and the subsequent rigorous research activity on the role of aerosols in climate change. 相似文献