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611.
612.
We discuss the background and methods for estimating uncertainty in a holistic manner in a regional terrestrial biota Full Carbon Account (FCA) using our experience in generating such an account for vast regions in northern Eurasia (at national and macroregional levels). For such an analysis, it is important to (1) provide a full account; (2) consider the relevance of a verified account, bearing in mind further transition to a certified account; (3) understand that any FCA is a fuzzy system; and (4) understand that a comprehensive assessment of uncertainties requires multiple harmonizing and combining of system constraints from results obtained by different methods. An important result of this analysis is the conclusion that only a relevant integration of inventory, process-based models, and measurements in situ generate sufficient prerequisites for a verified FCA. We show that the use of integrated methodology, at the current level of knowledge, and the system combination of available information, allow a verified FCA for large regions of the northern hemisphere to be made for current periods and for the recent past.  相似文献   
613.
The assessment of greenhouse gases (GHGs) emitted to and removed from the atmosphere is high on both political and scientific agendas internationally. As increasing international concern and cooperation aim at policy-oriented solutions to the climate change problem, several issues have begun to arise regarding verification and compliance under both proposed and legislated schemes meant to reduce the human-induced global climate impact. The approaches to addressing uncertainty introduced in this article attempt to improve national inventories or to provide a basis for the standardization of inventory estimates to enable comparison of emissions and emission changes across countries. Authors of the accompanying articles use detailed uncertainty analyses to enforce the current structure of the emission trading system and attempt to internalize high levels of uncertainty by tailoring the emissions trading market rules. Assessment of uncertainty can help improve inventories and manage risk. Through recognizing the importance of, identifying and quantifying uncertainties, great strides can be made in the process of Accounting for Climate Change.  相似文献   
614.
This paper identifies the literature that deals with adaptation to climate change in the transport sector. It presents a systematic review of the adaptations suggested in the literature. Although it is frequently claimed that this socially and economically important sector is particularly vulnerable to climate change, there is comparatively little research into its adaptation. The 63 sources we found are analysed following an action framework of adaptation. This distinguishes different adaptational functions and means of adaptation. By an open coding procedure, a total of 245 adaptations are found and classified. The paper shows a broad diversity of interdependent actors to be relevant—ranging from transportation providers to public and private actors and households. Crucial actors are hybrid in terms of being public or private. A substantial share of the identified adaptations follows a top-down adaptation policy pattern where a public or hybrid operator initiates action that affects private actors. Most of the exceptions from this pattern are technical or engineering measures. Identified adaptations mostly require institutional means, followed by technical means, and knowledge. Generally, knowledge on adapting transport to climate change is still in a stage of infancy. The existing literature either focuses on overly general adaptations, or on detailed technical measures. Further research is needed on the actual implementation of adaptation, and on more precise institutional instruments that fill the gap between too vague and too site-specific adaptations.  相似文献   
615.
Food and Environmental Virology - Infection with the tick-borne encephalitis virus (TBEV) can cause meningitis, meningoencephalitis and myelitis in humans. TBEV is an enveloped RNA virus of the...  相似文献   
616.
Individual heterogeneity and correlations between life history traits play a fundamental role in life history evolution and population dynamics. Unobserved individual heterogeneity in survival can be a nuisance for estimation of age effects at the individual level by causing bias due to mortality selection. We jointly analyze survival and breeding output from successful breeding attempts in an island population of Silvereyes (Zosterops lateralis chlorocephalus) by fitting models that incorporate age effects and individual heterogeneity via random effects. The number of offspring produced increased with age of parents in their first years of life but then eventually declined with age. A similar pattern was found for the probability of successful breeding. Annual survival declined with age even when individual heterogeneity was not accounted for. The rate of senescence in survival, however, depends on the variance of individual heterogeneity and vice versa; hence, both cannot be simultaneously estimated with precision. Model selection supported individual heterogeneity in breeding performance, but we found no correlation between individual heterogeneity in survival and breeding performance. We argue that individual random effects, unless unambiguously identified, should be treated as statistical nuisance or taken as a starting point in a search for mechanisms rather than given direct biological interpretation.  相似文献   
617.
Arctic and subarctic ecosystems are experiencing substantial changes in hydrology, vegetation, permafrost conditions, and carbon cycling, in response to climatic change and other anthropogenic drivers, and these changes are likely to continue over this century. The total magnitude of these changes results from multiple interactions among these drivers. Field measurements can address the overall responses to different changing drivers, but are less capable of quantifying the interactions among them. Currently, a comprehensive assessment of the drivers of ecosystem changes, and the magnitude of their direct and indirect impacts on subarctic ecosystems, is missing. The Torneträsk area, in the Swedish subarctic, has an unrivalled history of environmental observation over 100 years, and is one of the most studied sites in the Arctic. In this study, we summarize and rank the drivers of ecosystem change in the Torneträsk area, and propose research priorities identified, by expert assessment, to improve predictions of ecosystem changes. The research priorities identified include understanding impacts on ecosystems brought on by altered frequency and intensity of winter warming events, evapotranspiration rates, rainfall, duration of snow cover and lake-ice, changed soil moisture, and droughts. This case study can help us understand the ongoing ecosystem changes occurring in the Torneträsk area, and contribute to improve predictions of future ecosystem changes at a larger scale. This understanding will provide the basis for the future mitigation and adaptation plans needed in a changing climate.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01381-1) contains supplementary material, which is available to authorized users.  相似文献   
618.
理解底物碳氮对厌氧条件下水稻土排放氮素气体——氮气(N2)、氧化亚氮(N2O)和一氧化氮(NO)以及二氧化碳(CO2)和甲烷(CH4)的影响,有助于制定合理的温室气体减排措施,定量了解反硝化产物组成对碳底物水平的依赖性,也有助于氮转化过程模型研发中制定正确的关键过程参数选取方法或参数化方案.本研究采用粉砂壤质水稻土为研究对象,设置对照(CK)和加碳(C+)两个处理,前者的初始硝态氮和可溶性有机碳(DOC)含量分别为~50 mg·kg-1和~28 mg·kg-1,后者的分别为~50 mg·kg-1和~300 mg·kg-1.采用氦环境培养-气体及碳氮底物直接同步测定系统,研究了完全厌氧条件下碳底物水平对上述气体排放的影响.结果表明,CK处理无CH4排放,而C+处理可观测到CH4排放;C+处理的综合增温潜势显著高于CK处理(P<0.01);NO、N2O和N2排放量占这3种氮素气体排放总量的比重,在CK处理分别约为9%、35%和56%,在C+处理分别约为31%、50%和19%,处理间差异显著(P<0.01).由此表明,碳底物水平可显著改变所排放氮素气体的组成;对于旱地阶段硝态氮比较丰富的水稻土,避免在淹水前或淹水期间施用有机肥,有利于削减温室气体排放.  相似文献   
619.
The aim of the present study was to estimate spillover effects between the work and the family sphere in a sample of nurses (N = 2058). Hierarchical regression analyses investigated whether shift work schedules were associated with negative or positive spillover, both from family to work and vice versa, controlling for demographic factors, job demands and decision latitude. With daytime work as a reference group, all types of shift work (day and evening shift, night shift only and rotating 3 shift) were associated with higher negative work-to-family spillover. Night work was associated with significantly less negative family-to-work spillover. None of the different shift work schedules were related to any type of positive spillover. The results indicate that working outside of daytime hours is less compatible with workers’ family lives, compared to working ordinary day shifts. On the other hand, working night shifts only was associated with reduced negative family-to-work spillover.  相似文献   
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