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101.
许荣 《辽宁城乡环境科技》2012,(3):69-71
对盖州市"十一五"期间大气环境质量进行研究,采用Daniel趋势检验法定量分析该地区大气环境质量的变化规律与发展趋势,探讨污染成因与特征,并提出综合防治措施。 相似文献
102.
Du Xile 《中国人口.资源与环境(英文版)》2013,11(4):44-51
Abstract Water pollution is one of the major environmental problems, especially in urban areas. Due to rapid urban expansion and industrialization, water pollution in Zhengzhou City, the capital of Henan Province in central China has become a serious problem for its development. In this study, the surface water quality was evaluated using Nemerow Comprehensive Pollution Index (NCPI), and the change trend was calculated using methods of Mann-Kendall test and Sen’s slope estimator, based on the monitoring data from 1998 to 2008. The results show that the NCPI ranged from 3 to 50 in 70% of the monitoring cases, implying that most rivers were seriously polluted. However, this serious polltuon is expected to be gradually improved, as the concentration of water pollutants and NCPI declined significantly in most rivers. Water pollution in reservoirs was much lower than rivers, and the NCPI in the three monitored reservoirs was lower than 3 in most years, and shows a downward trend. Although the surface water quality was gradually improved, great efforts are still needed to enhance the protection and improvement of surface water environment. 相似文献
103.
居民生活直接能源消费是重要的大气污染物和温室气体排放来源,识别其历史排放趋势是科学制定管控策略的基础.然而目前我国尚缺乏省级尺度居民生活能源消费排放趋势的研究.以广东省为研究对象,通过广泛收集居民生活直接能源消费数据和排放因子,建立了2006—2017年广东省居民生活直接能源消费大气污染物和温室气体排放清单,并采用情景分析法量化了能源结构变化对居民生活直接能源消费大气污染物与温室气体排放的影响.结果表明:①2006—2017年居民生活直接能源消费排放的大气污染物和温室气体均呈下降趋势,CO、PM2.5、BC、OC、CH4、CO2和N2O排放量分别下降70%、59%、59%、66%、77%、30%和73%;②城乡贡献上,乡村居民生活直接能源消费是大气 污染物和温室气体排放的主要来源,排放分担率分别在70%和60%以上;③空间分布上,2017年广东省居民生活直接能源消费大气污染物和温室气体排放主要集中在粤东、粤西传统燃料消费量较高的地区,以及广州、东莞和深圳等人口密度较大的城市地区;④能源结构清洁化所致的2006—2017年广东省居民生活直接能源消费大气污染物和温室气体减排比例为38%~88%;⑤以2025年为目标年,居民生活能源结构持续清洁化发展能够进一步降低居民生活直接能源消费大气污染物和温室气体排放,尤其对CO、PM2.5、BC、CH4和N2O的减排比例均在80%以上. 相似文献
104.
近50年长江流域降水日数的演变趋势 总被引:2,自引:0,他引:2
通过分析不同强度降水量(大于75百分位和大于95百分位降水,下同)对应降水日数,研究了长江流域1951~2000年逐年和年代际降水日数变化趋势。大于75百分位的降水日数在上游以及中游的北岸增加趋势最显著,四川盆地是唯一显示减少趋势的地区。同样,大于95百分位的降水日数在中游和下游也表现出十分明显的增加趋势,呈现减少趋势的仍然是四川盆地,并略向其北方延伸。详细分析每10年的平均降水日数的距平发现,大于75百分位降水日数最大的正距平集中在中游的1980s、1990s和下游的1980s。最大的负距平也是在中游地区,发生在1950~1979年。因此,中游的降水日数增加的幅度最大。对于大于95百分位降水日数,长江流域中游和下游的变化趋势也是一致的,在1960s 和1970s的负距平后,都出现较大的正距平。上游降水日数的年际变化要小于中下游。比较不同百分位降水日数的变化趋势,可将长江流域1950~2000年降水日数的变化趋势分为3种类型:(1)在大于75百分位降水日数增加的同时,大于95百分位降水日数却有所减少;(2)大于75和大于95百分位降水日数同时呈减少的趋势;(3)大于75和大于95百分位降水日数同时呈增加趋势。 相似文献
105.
In this study we analyze the temporal evolution of the suspended particulated matter (SPM) in the air of the six Spanish remote stations belonging to the European Monitoring and Evaluation Programme network. A negative trend is observed in three of them and a positive trend in one. Another objective of this work was to know the geographical sources of SPM in Spain. To do this we used the conditional probability functions (cf. Ashbaugh et al. (1985), Atmos. Environ., 19, 1263–1270) and information about air masses trajectories. The North of Africa and regions inside Spain are the main sources while Continental Europe and the British Islands are less important. 相似文献
106.
淮河中上游参考作物腾发量趋势变化及其成因 总被引:1,自引:0,他引:1
参考作物腾发量(ET0)是由平均气温(Tm)、实际水汽压(ea)、风速(u2)和净辐射(Rn)等多个气候要素驱动的,因此,气候变化对ET0的影响是显而易见的。分析ET0和各气候要素的时空变化特征可以获得气候变化对ET0的影响。利用Mann-Kendall(MK)检验分析了淮河中上游流域1959—2009年ET0及各气候要素的变化趋势。并且利用偏相关分析和贡献分析获得ET0和主要气候要素之间的定性和定量关系。结果显示,大部分站点的年ET0表现出显著的下降趋势。在夏季,所有站点的ET0都表现出显著的下降趋势,且西北部地区尤其显著。其他3个季节显著下降的ET0趋势主要分布在淮河中上游流域的西北部地区。年及夏季的ET0在1970年以后表现出下降的趋势并且在1975年以后变的显著,其余3个季节ET0并无明显变化特征,说明夏季ET0的显著减少是年ET0显著减少的主要原因;实际水汽压与ET0之间表现出显著的负相关关系,而平均温度、净辐射和风速则表现出显著的正相关关系;无论从定性的偏相关关系还是定量的贡献分析都可看出虽然年及四季的平均气温是显著上升的,并且导致了ET0的增加,但是整个流域显著下降的风速和净辐射直接导致了年及夏季ET0的显著减少。 相似文献
107.
Ram B. Jain 《毒物与环境化学》2018,100(1):115-133
Data from National Health and Nutrition Examination Survey for children aged 6–11 years for 1999–2014 were used to study time trends and factors affecting the urinary levels of barium, cobalt, cesium, molybdenum, lead, antimony, thallium, and tungsten. Adjusted levels in urine declined every two years by 5.9% for barium, by 1.2% for cesium, by 18.2% for lead, and by 14% for antimony. For every additional smoker smoking inside a home, the levels of barium increased by 10.6% and for lead by 10%, but for tungsten levels decreased by 7.7%. 相似文献
108.
J. Rolf Olsen Jery R. Stedinger Nicholas C. Matalas Eugene Z. Stakhiv 《Journal of the American Water Resources Association》1999,35(6):1509-1523
ABSTRACT: This paper considers the distribution of flood flows in the Upper Mississippi, Lower Missouri, and Illinois Rivers and their relationship to climatic indices. Global climate patterns including El Niño/Southern Oscillation, the Pacific Decadal Oscillation, and the North Atlantic Oscillation explained very little of the variations in flow peaks. However, large and statistically significant upward trends were found in many gauge records along the Upper Mississippi and Missouri Rivers: at Hermann on the Missouri River above the confluence with the Mississippi (p = 2 percent), at Hannibal on the Mississippi River (p < 0.1 percent), at Meredosia on the Illinois River (p = 0.7 percent), and at St. Louis on the Mississippi below the confluence of all three rivers (p = 1 percent). This challenges the traditional assumption that flood series are independent and identically distributed random variables and suggests that flood risk changes over time. 相似文献
109.
António O. Soares Danny Haelewaters Olga M. C. C. Ameixa Isabel Borges Peter M. J. Brown Pedro Cardoso Michiel D. de Groot Edward W. Evans Audrey A. Grez Axel Hochkirch Milada Holecová Alois Honěk Ján Kulfan Ana I. Lillebø Zdenka Martinková J. P. Michaud Oldřich Nedvěd Omkar Helen E. Roy Swati Saxena Apoorva Shandilya Arnaud Sentis Jiri Skuhrovec Sandra Viglášová Peter Zach Tania Zaviezo John E. Losey 《Conservation biology》2023,37(1):e13965
Ladybirds (Coleoptera: Coccinellidae) provide services that are critical to food production, and they fulfill an ecological role as a food source for predators. The richness, abundance, and distribution of ladybirds, however, are compromised by many anthropogenic threats. Meanwhile, a lack of knowledge of the conservation status of most species and the factors driving their population dynamics hinders the development and implementation of conservation strategies for ladybirds. We conducted a review of the literature on the ecology, diversity, and conservation of ladybirds to identify their key ecological threats. Ladybird populations are most affected by climate factors, landscape composition, and biological invasions. We suggest mitigating actions for ladybird conservation and recovery. Short-term actions include citizen science programs and education, protective measures for habitat recovery and threatened species, prevention of the introduction of non-native species, and the maintenance and restoration of natural areas and landscape heterogeneity. Mid-term actions involve the analysis of data from monitoring programs and insect collections to disentangle the effect of different threats to ladybird populations, understand habitat use by taxa on which there is limited knowledge, and quantify temporal trends of abundance, diversity, and biomass along a management-intensity gradient. Long-term actions include the development of a worldwide monitoring program based on standardized sampling to fill data gaps, increase explanatory power, streamline analyses, and facilitate global collaborations. 相似文献
110.
全球CO_2排放研究趋势及其对我国的启示 总被引:2,自引:0,他引:2
近几年,全球气候变暖已经成为国际社会的共识,由此而引发的温室气体减排计划也陆续在主要发达国家开始实施,有关CO_2排放问题的研究也成为全球的学术焦点.通过对全球CO_2排放研究趋势的总结发现:首先,国际社会有关CO_2排放的核算方法不断完善,从IPCC(1995)到IPCC(2006),内容更加完善,方法更趋合理;其次,排放责任的区分日益公平合理,随着"碳转移"和"碳泄露"问题研究的深入,有关排放责任区分方法的研究逐渐在从生产视角向消费视角转变;第三,排放因素分解逐步深入,分解公式包括KAYA公式和投入产出公式,分解方法从指数法到平均对数法再到微积分法,分解模型日趋成熟和多元化;第四,排放预测模型也不断综合化、长期化,自上而下模型和自下而上模型逐渐相互借鉴和融合.在此基础上,笔者对我国CO_2排放研究提出了几点启发,即加快排放因子数据库建设,重视责任排放和结构分析研究,提高自主建模的水平和完善我国技术环境数据库等.以期提高我国对温室气体排放现状和历史的认识,在国际气候变化领域发挥积极的作用. 相似文献