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31.
Uncertainties and recommendations 总被引:1,自引:0,他引:1
Callaghan TV Björn LO Chernov Y Chapin T Christensen TR Huntley B Ims RA Johansson M Jolly D Jonasson S Matveyeva N Panikov N Oechel W Shaver G 《Ambio》2004,33(7):474-479
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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Thomas P. Wagner Leonard Ortolano 《Journal of the American Water Resources Association》1975,11(2):329-344
ABSTRACT: The growing demands by the public for a more active role in planning have recently generated considerable interest among researchers and planners in the subject of public involvement techniques. Numerous surveys have found that standard public participation techniques (e.g., public hearings) by themselves are considered inadequate. Several techniques that have potential for overcoming some of the limitations of standard public involvement techniques have recently been developed. This paper describes several of these new techniques and analyzes each of them in terms of their potential utility in water resources planning. 相似文献
34.
Uwe Heiser Stefan Norra Doris Stüben Magnus von Wagner 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(1):15-19
Für die Anwendung der sequentiellen Schwermetallextraktion auf Proben, die nur im Milligramm-Bereich erhalten werden k?nnen
(Mikroproben, wie z. B. Staubniederschl?ge), wurde die Methode vonZeien &Brümmer (1989) weiterentwickelt. Der Extraktionsma?stab wurde um den Faktor 1∶100 verringert und die Reproduzierbarkeit des Verfahrens
mit variablen Probenmengen um 20mg und einem Extraktionsvolumen von 500 μl mit Hilfe von Standardb?den nachgewiesen. M?gliche
Einflüsse variabler Extraktionsverh?ltnisse (Verh?ltnis von Probenmenge zu Extraktionsvolumen) sowie eine aufwendige Vorbehandlung
von Staubproben, die nach der Bergerhoff-Methode (VDI 2119/2, 1972) gesammelt wurden, lagen bei diesen Untersuchungen weitgehend
im Variationsbereich des Verfahrens. Die sequentielle Extraktion kann folglich zur Untersuchung der Mobilisierbarkeit von
Schwermetallen auch aus Mikroproben mit variablen Probenmengen eingesetzt werden.
Mit Hilfe dieses Verfahrens wurden die Mobilisierbarkeiten von Zink, Kupfer und Blei der Schluff- und Tonfraktion von Stra?ensedimenten
mit Staubniederschl?gen an zwei urbanen Standorten mit unterschiedlicher, verkehrsbedingter Schwermetallbelastung verglichen.
Diese Untersuchungen werden in Teil 2 (“Sequentielle Schwermetallextraktion von st?dtischen St?uben”) vorgestellt. 相似文献
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Sven Rannow Nicholas A. Macgregor Juliane Albrecht Humphrey Q. P. Crick Michael Förster Stefan Heiland Georg Janauer Mike D. Morecroft Marco Neubert Anca Sarbu Jadwiga Sienkiewicz 《Environmental management》2014,54(4):732-743
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
38.
Sven Erik J rgensen 《生态毒理学报》2001,23(1):32-34,35
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
39.
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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