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It is easy to get lost in the vast amount of knowledge that is currently produced. In this study, to get a comprehensive picture
of current scientific knowledge about global warming issues, we developed a mapping framework for global warming research
based on the relationships between nature and human society. The mapping includes seven phases: (1) socioeconomic activity
and greenhouse gas emissions, (2) carbon cycle and carbon concentration, (3) climate change and global warming, (4) impacts
on ecosystems and human society, (5) adaptation, (6) mitigation, and (7) social systems. We applied the findings of the Intergovernmental Panel on Climate Change Fourth Assessment Report to the mapping. The quantity of research results and their reliability were analyzed on the basis of expert judgment to better
understand the extent to which current scientific knowledge provides answers to society’s major concerns. The quantity and
reliability of answers have increased in phases 2 and 3 relative to research in the Third Assessment Report. Although a large quantity of results have been produced in phases 4 and 6, they are not always sufficient. More studies
are required in phases 1, 5, and 7, and the reliability of existing knowledge needs to be improved in these phases. Mapping
global warming issues enabled us to visually comprehend the numerous and varied parts of global warming research as a whole
and to discern gaps in knowledge and other research shortfalls.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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探讨多环芳烃在胎盘中的分布,并对其进行源解析。从2012年6月—2013年6月在云南省第一人民医院产科分娩的产妇中随机抽取30例,利用气相色谱-质谱联用仪(GC-MS)检测其胎盘中多环芳烃的含量;比较胎盘的中央部分和边缘部分多环芳烃含量的差异;对多环芳烃进行源解析,探讨其主要来源。胎盘中检测到多种多环芳烃成分;其中2~4个苯环的多环芳烃占总量的90%以上,尤其是萘、苊、芴、菲、蒽、芘、荧蒽的含量较高;萘、苊烯、苊、茚并(1,2,3-c,d)芘、二苯并(a,h)蒽5种多环芳烃在胎盘中央的含量高于边缘,具有显著性差异(P0.05),其他多环芳烃在胎盘中央和边缘的含量无显著性差异(P0.05)。多环芳烃源解析提示80%研究对象体内的多环芳烃主要来自石油产品的燃烧或暴露于石油产品。 相似文献
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Stuart W. Krasner Ai Ji Chih-Fen T. Lee Raha Shirkhani Joshua M. Allen Susan D. Richardson Michael J. Plewa 《环境科学学报(英文版)》2022,34(7):161-172
A survey was conducted at eight U.S. drinking water plants, that spanned a wide range of water qualities and treatment/disinfection practices. Plants that treated heavily-wastewater-impacted source waters had lower trihalomethane to dihaloacetonitrile ratios due to the presence of more organic nitrogen and HAN precursors. As the bromide to total organic carbon ratio increased, there was more bromine incorporation into DBPs. This has been shown in other studies for THMs and selected emerging DBPs (HANs), whereas this study examined bromine incorporation for a wider group of emerging DBPs (haloacetaldehydes, halonitromethanes). Moreover, bromine incorporation into the emerging DBPs was, in general, similar to that of the THMs. Epidemiology studies that show an association between adverse health effects and brominated THMs may be due to the formation of brominated emerging DBPs of heath concern. Plants with higher free chlorine contact times before ammonia addition to form chloramines had less iodinated DBP formation in chloraminated distribution systems, where there was more oxidation of the iodide to iodate (a sink for the iodide) by the chlorine. This has been shown in many bench-scale studies (primarily for iodinated THMs), but seldom in full-scale studies (where this study also showed the impact on total organic iodine. Collectively, the THMs, haloacetic acids, and emerging DBPs accounted for a significant portion of the TOCl, TOBr, and TOI; however, ∼50% of the TOCl and TOBr is still unknown. The correlation of the sum of detected DBPs with the TOCl and TOBr suggests that they can be used as reliable surrogates. 相似文献
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本文介绍了河西草地资源的空间分布与不同等级面积统计 ,客观地分析了草地“三化”的主导诱因在不同区域上的差异表现 ,突出了河西地区整体荒漠化的严峻现实。并进一步从生态恢复的规律要求、草地独特的生态环境效益、草地建设的相对低成本 ,及草产业的广阔市场前景等方面 ,阐述了河西进行草地建设的现实意义 ,提出了一些独到的见解 相似文献
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