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31.
Quantifying uncertainty in the biospheric carbon flux for England and Wales   总被引:1,自引:0,他引:1  
Summary.  A crucial issue in the current global warming debate is the effect of vegetation and soils on carbon dioxide (CO2) concentrations in the atmosphere. Vegetation can extract CO2 through photosynthesis, but respiration, decay of soil organic matter and disturbance effects such as fire return it to the atmosphere. The balance of these processes is the net carbon flux. To estimate the biospheric carbon flux for England and Wales, we address the statistical problem of inference for the sum of multiple outputs from a complex deterministic computer code whose input parameters are uncertain. The code is a process model which simulates the carbon dynamics of vegetation and soils, including the amount of carbon that is stored as a result of photosynthesis and the amount that is returned to the atmosphere through respiration. The aggregation of outputs corresponding to multiple sites and types of vegetation in a region gives an estimate of the total carbon flux for that region over a period of time. Expert prior opinions are elicited for marginal uncertainty about the relevant input parameters and for correlations of inputs between sites. A Gaussian process model is used to build emulators of the multiple code outputs and Bayesian uncertainty analysis is then used to propagate uncertainty in the input parameters through to uncertainty on the aggregated output. Numerical results are presented for England and Wales in the year 2000. It is estimated that vegetation and soils in England and Wales constituted a net sink of 7.55 Mt C (1 Mt C = 1012 g of carbon) in 2000, with standard deviation 0.56 Mt C resulting from the sources of uncertainty that are considered.  相似文献   
32.
1938年夏天,美国年轻学者科尼利尔斯·奥斯古德为了履行与燕京大学的合作计划,不远万里来到滇池西岸一个名不见经传的小村庄调查.1961年,他开启尘封的笔记本,整理旧资料,补充新文献,完成了<旧中国的农村生活:对云南高峣的社区研究>.70年过去,重温科尼利尔斯·奥斯古德的研究历程,我们仍会从中获得许多有益的启示.  相似文献   
33.
In this work, some corporate websites of the chemical industry of Tarragona (Spain) are studied, analysing how the chemical trade associations and companies present information and/or encourage dialogue with the community on issues relating to the chemical risk and their environmental, health and safety (EHS) performance. The results suggest that the chemical industry in Tarragona uses the corporate websites mainly to disseminate information about its EHS commitments and performance, but they do not encourage dialogue with the community through the Internet.  相似文献   
34.
Over the last ten years in Australia the social component of Australian Environmental Impact statements has gradually increased in size as the importance of Social Impact Analysis has been recognised. This commendable trend has not been without mishap, however, and there remain many areas largely ignored in Social Impact Assessment. This paper seeks to identify these areas, identifying value questions that need to be addressed in the preparation of the social impact component.  相似文献   
35.
Using an overlapping-generations model in which households may have either finite or infinite horizons, I derive the implications of each horizon for the steady-state real interest rate. I then formulate an econometric model of the steady-state real interest rate and devise tests that can distinguish between finite and infinite horizons. These tests are applied to annual and quarterly U.S. data, which span the period 1875–1988. The results are inconsistent with finite horizons, and broadly consistent with infinite horizons.  相似文献   
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D. E. Super's (1957) theory of career development has long been of interest to careers researchers (M. Savickas, 1994; S. C. Whiston & B. K. Brecheisen, 2002). Its insightful illustration of career stages has made it widely applied by careers practitioners. Image norms may influence the career decisions and developmental tasks inherent in each stage. An image norm is the belief that individuals must present or possess a certain image, consistent with occupational, organizational, or industry standards, in order to achieve career success. Understanding the effects of image norms across D. E. Super's (1957) career stages has important implications for individuals, organizations, and career counseling professionals.  相似文献   
39.
This article provides an overview of social trust, examining its various aspects and components. Trust is best understood in a sociological sense by focusing on its important relational characteristic. Following this lead, the article discusses briefly how social trust relates to social capital and examines factors that shape the development of social trust, along with outcomes related to variations in trust, classifying them by analytical level (i.e., individual, community, group, organizational, and societal). The article concludes by assessing the strengths and weaknesses of existing research and by identifying some important questions that have not yet been adequately addressed.  相似文献   
40.
The objective of this study was to examine the links between coping and attachment. In a longitudinal study of 112 participants, coping behavior was assessed at five points in time during adolescence (starting at the age of 14 years) and early adulthood. In addition, at the age of 21 years, state of mind regarding current and earlier attachment experiences was assessed by employing the Adult Attachment Interview (AAI). In both adolescence and early adulthood, differences in coping styles were found to be related to differences in attachment. Individuals classified as secure dealt with their problems more actively by using their social network during adolescence and at the age of 21 years. Both secure and dismissing individuals used more internal coping than those with a preoccupied state of mind. Latent growth curve modeling revealed that differences in active and internal coping between secure and insecure individuals applied to the rate of change in these coping styles between 14 and 21 years, with participants in the secure group showing much steeper growth in both coping styles. Only minor differences were found with respect to withdrawal as a coping style. The results represent first evidence that coping trajectories during adolescence and young adulthood are linked with attachment state of mind.  相似文献   
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