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21.
Editorial     
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Uncertainties and recommendations   总被引:1,自引:0,他引:1  
An assessment of the impacts of changes in climate and UV-B radiation on Arctic terrestrial ecosystems, made within the Arctic Climate Impacts Assessment (ACIA), highlighted the profound implications of projected warming in particular for future ecosystem services, biodiversity and feedbacks to climate. However, although our current understanding of ecological processes and changes driven by climate and UV-B is strong in some geographical areas and in some disciplines, it is weak in others. Even though recently the strength of our predictions has increased dramatically with increased research effort in the Arctic and the introduction of new technologies, our current understanding is still constrained by various uncertainties. The assessment is based on a range of approaches that each have uncertainties, and on data sets that are often far from complete. Uncertainties arise from methodologies and conceptual frameworks, from unpredictable surprises, from lack of validation of models, and from the use of particular scenarios, rather than predictions, of future greenhouse gas emissions and climates. Recommendations to reduce the uncertainties are wide-ranging and relate to all disciplines within the assessment. However, a repeated theme is the critical importance of achieving an adequate spatial and long-term coverage of experiments, observations and monitoring of environmental changes and their impacts throughout the sparsely populated and remote region that is the Arctic.  相似文献   
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新疆煤田火灾的成因、危害及综合治理   总被引:3,自引:0,他引:3  
新疆是世界上煤田火灾最严重的地区,原因主要是新疆地处欧亚大陆腹地,具典型的大陆性干旱气候;新疆地区煤系为中下侏罗纪,地质活动较为剧烈;小煤窑的乱采滥挖等.新疆煤田火灾带来巨大危害:损失煤炭资源、污染环境、引发地质灾害、破坏生态平衡及危害生物健康等.对煤田火灾进行综合治理已经成为当务之急.为了有效灭火,应先对火区进行探测.探测方法有磁异常探测法、自然电场法和红外地面测温法等.然后因地制宜地选择适当的灭火技术进行灭火.灭火之后还应利用地理信息系统等方法对火区进行动态监测.  相似文献   
26.
Managing Protected Areas Under Climate Change: Challenges and Priorities   总被引:1,自引:0,他引:1  
The implementation of adaptation actions in local conservation management is a new and complex task with multiple facets, influenced by factors differing from site to site. A transdisciplinary perspective is therefore required to identify and implement effective solutions. To address this, the International Conference on Managing Protected Areas under Climate Change brought together international scientists, conservation managers, and decision-makers to discuss current experiences with local adaptation of conservation management. This paper summarizes the main issues for implementing adaptation that emerged from the conference. These include a series of conclusions and recommendations on monitoring, sensitivity assessment, current and future management practices, and legal and policy aspects. A range of spatial and temporal scales must be considered in the implementation of climate-adapted management. The adaptation process must be area-specific and consider the ecosystem and the social and economic conditions within and beyond protected area boundaries. However, a strategic overview is also needed: management at each site should be informed by conservation priorities and likely impacts of climate change at regional or even wider scales. Acting across these levels will be a long and continuous process, requiring coordination with actors outside the “traditional” conservation sector. To achieve this, a range of research, communication, and policy/legal actions is required. We identify a series of important actions that need to be taken at different scales to enable managers of protected sites to adapt successfully to a changing climate.  相似文献   
27.
The chemical composition of the odors typical of fires has recently been deciphered. Basically the constituents are mixtures of acetophenone, benzyl alcohol, hydroxylated derivatives of benzaldehyde, methoxylated and/or alkylated phenols and naphthalene. This finding makes it possible to develop objective, practical analytic measurement methods for the burnt smell as a contribution to improving fire damage assessment and remediation monitoring. With the aid of an artificially produced burnt smell and a panel of testers the odor detection threshold of a test mixture was determined olfactometrically to 2 μg m−3. Using a defined burnt-smell atmosphere in a test chamber, analytical methods with active sampling, the adsorbents XAD 7 and TENAX TA, and GC/MS measurement were then optimized and tested with a view to being able to carry out sensitive quantitative measurement of burnt smells. A further practical method with particular application to the qualitative characterization of this odor is based on the use of a new SPME (solid-phase microextraction) field sampler with DVB/CAR/PDMS (divinylbenzene/Carboxen™/polydimethylsiloxane) fibers.  相似文献   
28.
Hammarström L  Kullander S 《Ambio》2012,41(Z2):101-102
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29.
为了管理和保护城市水资源,需要有各种各样的方法 .污水处理是昂贵的,而且发展中国家经常使用的 2- 4步处理也阻碍了他们的污水处理 .化学沉淀法和废水稳定池+构造湿地组合法常常可以明显地减少对水资源的冲击 .建议发展中国家最好考虑采用这些方法 .  相似文献   
30.
Tarsal substrate adhesion in insects is based on the effect of a thin film of liquid in the contact zone, which is deposited as droplets on the surface an insect has walked on, but as yet, little is known about the chemical composition of the liquid. In the present study, interference reflection microscopical images of the tarsal contact and footprints of Gastrophysa viridula (Coleoptera: Chrysomelidae) are depicted and the chemical composition of tarsal liquids and cuticular components are investigated by means of solid-phase microextraction and solvent extraction of whole beetles and footprints. Based on this comparative methodical approach, we are first to provide evidence from direct sampling for the chemical congruence of cuticular lipids and tarsal liquid in beetles. Furthermore, differences resulting from the applied sampling techniques are assessed and advantages of the respective methods are discussed.  相似文献   
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