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CNPC turned a profit last year
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《China Oil & Gas》 CAS 1995年第1期13-13,共1页
CNPCturnedaprofitlastyearForthefirsttimesince1988,China'sonshorepetroleumindustryturnedaprofitlastyear-thank... CNPCturnedaprofitlastyearForthefirsttimesince1988,China'sonshorepetroleumindustryturnedaprofitlastyear-thankstooilpriceadjust... 展开更多
关键词 CNPC turned a profit last year
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The Consumer Price Index of Residents in Cities and Countryside in July 1997(Same period of last year=100)
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《World Economy & China》 SCIE 1997年第5期49-49,共1页
关键词 Same period of last year
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Disastrous Rains Downpours and flooding cause more problems for the area hie hard by last year’s earthquake
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作者 LI LI 《Beijing Review》 2009年第31期19-19,共1页
At least six people were killed on July 25 when a rockslide smashed into a bridge in Wenchuan County,ithe epicenter of last
关键词 Disastrous Rains Downpours and flooding cause more problems for the area hie hard by last year’s earthquake
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Listed Lithium Companies Released Last Year's Performance–Who Enjoyed the Bonus of the Era?
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《China Nonferrous Metals Monthly》 2017年第3期5-10,共6页
The year 2016 is the year of change for China’s new energy vehicles industry,and also the key year in which the industry walks into the growth period from a lead-in period.The opportunities were obvious,and challenge... The year 2016 is the year of change for China’s new energy vehicles industry,and also the key year in which the industry walks into the growth period from a lead-in period.The opportunities were obvious,and challenges extremely difficult to meet.On one hand,many lithium battery enterprises suffered from a long account period,slowly returned money or 展开更多
关键词 net Who Enjoyed the Bonus of the Era Listed Lithium Companies Released last year’s Performance
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Characteristics of Temperature Change in China over the Last 2000 years and Spatial Patterns of Dryness/Wetness during Cold and Warm Periods 被引量:10
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作者 Quansheng GE Haolong LIU +2 位作者 Xiang MA Jingyun ZHENG Zhixin HAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第8期941-951,共11页
This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation ... This paper presents new high-resolution proxies and paleoclimatic reconstructions for studying climate changes in China for the past 2000 years. Multi-proxy synthesized reconstructions show that temperature variation in China has exhibited significant 50–70-yr, 100–120-yr, and 200–250-yr cycles. Results also show that the amplitudes of decadal and centennial temperature variation were 1.3℃ and 0.7℃, respectively, with the latter significantly correlated with long-term changes in solar radiation, especially cold periods, which correspond approximately to sunspot minima. The most rapid warming in China occurred over AD 1870–2000, at a rate of 0.56°± 0.42℃(100 yr)^(-1); however, temperatures recorded in the 20 th century may not be unprecedented for the last 2000 years, as data show records for the periods AD 981–1100 and AD1201–70 are comparable to the present. The ensemble means of dryness/wetness spatial patterns in eastern China across all centennial warm periods illustrate a tripole pattern: dry south of 25°N, wet from 25°–30°N, and dry to the north of 30°N. However, for all centennial cold periods, this spatial pattern also exhibits a meridional distribution. The increase in precipitation over the monsoonal regions of China associated with the 20 th century warming can primarily be attributed to a mega El Nino–Southern Oscillation and the Atlantic Multidecadal Oscillation. In addition, a significant association between increasing numbers of locusts and dry/cold conditions is found in eastern China. Plague intensity also generally increases in concert with wetness in northern China, while more precipitation is likely to have a negative effect in southern China. 展开更多
关键词 temperature change dry-wet spatial pattern cold and warm periods last 2000 years China
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The sub-fossils of leaf fragments in sediments as an indicator of mangrove development in the Yingluo Bay, Guangxi, Southwest China over the last 130 years 被引量:1
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作者 Wanzhu Wang Xianwei Meng +1 位作者 Xiangqin Wang Zhen Li 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第8期27-34,共8页
Located in the intertidal zone of the tropical and subtropical coasts, mangrove forests are an important ecosystem in the global carbon cycle and serve as a protector of local seashores. Under the double impacts of cl... Located in the intertidal zone of the tropical and subtropical coasts, mangrove forests are an important ecosystem in the global carbon cycle and serve as a protector of local seashores. Under the double impacts of climate change,especially sea-level rise, and human activity, mangrove forests around the world have faced degradation, against which the reconstruction of the historical development of mangrove forests using an effective indicator has been regarded as a necessary strategy for designing a predictable model. As the primary product of mangrove forest, it is reasonable that the content of leaf fragments of mangrove(CLFM) buried in sediments in the form of sub-fossils potentially has the same indicative function for the development of mangrove forests as that of widely-used mangrove pollen. In this study, the leaf fragments of mangrove in two sediment cores(YLW02 and YLW03) drilled in the Yingluo Bay in Guangxi, Southwest China were picked out and weighted for calculation of CLFM, which was used as an indicator of mangrove development after examination of parallelism and a statistical correlation of the CLFM with the concentration of mangrove pollen. The results clearly show that the vertical distribution of the CLFM for the core taken from the landward margin of mangrove forests(YLW03) only parallels that of the local mangrove species(Rhizophora. stylosa) with a significantly positive correlation(R=0.56, P=0.05), while the vertical distribution of the CLFM for the core taken from the interface between seaward margin of mangrove forest and the trunk of tidal creeks of the bay(YLW02) parallels the summed concentration of mangrove pollen(SCMP) with a more positive correlation than that of YLW03(R=0.85, P=0.01), indicating that the trunk outlet of tidal creeks must have been the site where mangrove production gathered from the overall forest rather than from local production. The variations in the CLFM of both cores indicate that overall the mangrove forests in the Yingluo Bay have increasingly flourished over the last 130 years except for the interval of 1940–1950 AD in response to an increase in air temperature and decrease in rainfall, which would have resulted in an increase in seawater salinity;while the coupled extreme increases in air temperature and in rainfall in summer, which would have resulted in extreme decreases in seawater salinity, would be responsible for the relative degradation of mangrove forests in the interval of 1940–1950 AD. 展开更多
关键词 LEAF fragment MANGROVE DEVELOPMENT Yingluo BAY last 130 yearS air temperature and rainfall
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Analysis of Climate Change in the Coastal Zone of Eastern China, against the Background of Global Climate Change over the Last Fifty Years: Case Study of Shandong Peninsula, China 被引量:2
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作者 Qing Tian Qing Wang +2 位作者 Chao Zhan Xiguo Li Xueping Liu 《International Journal of Geosciences》 2012年第2期379-390,共12页
The climate change in Shandong Peninsula, China was analyzed in this paper by the non-parametric Mann-Kendall test, Accumulated Difference Curve and Order Cluster Analysis methods, based upon the datas of annual mean,... The climate change in Shandong Peninsula, China was analyzed in this paper by the non-parametric Mann-Kendall test, Accumulated Difference Curve and Order Cluster Analysis methods, based upon the datas of annual mean, maximum and minimum temperature and annual precipitation, precipitation from June to September over the past 50 years. Results obtained showed a number of observations: 1) The annual mean temperature of Shandong Peninsula showed a significant increasing trend, with a distinct abrupt change point detected around 1990, during the past 5 decades. The warming of the Peninsula over the last 50 years was due mainly to the significant increase of annual minimum temperature. The annual maximum temperature demonstrated a mixed trend of decreasing and increasing, but was statistically insignificant, and no abrupt change was detected;2) The annual precipitation exhibited a decreasing trend during the past 5 decades, with an abrupt change detected around 1980 at most stations;but there was an earlier transition point at 1966, at a few stations. The reduction in precipitation, from June to September, was responsible mainly for the decrease of annual precipitation. Besides, the proportion of the June-September precipitation in the year declined slightly over the last 50 years;3) In comparison, the temperature evolution in Shandong Peninsula was basically consistent with most parts of China, but warmed at a faster rate over the same period;the decreasing trend of precipitation was more significant compared with the other climate zones of China. Within the Peninsula, the abrupt change of temperature and precipitation in the Southeast was earlier than that in the Northwest;the reduction of precipitation was larger in the Southeast while the increase of temperature was more significant in the Northwest. This research was of great importance to understand the climate change and its environmental effects in the coastal zone. 展开更多
关键词 ABRUPT CHANGE Climate CHANGE SHANDONG PENINSULA in China The last Fifty yearS Coastal Zone
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近四十年来国内宋代茶诗研究的回顾与展望 被引量:1
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作者 李精耕 曾思莹 《农业考古》 北大核心 2024年第2期201-207,共7页
近四十年来,随着中国茶文化研究的日益深入,茶诗研究热度的上升,学界对宋代茶诗的关注和研究也逐渐增多。其研究历程大致可分为三个阶段:1984-2000年,为研究发轫期;2001-2016年,为研究蓬勃发展期;2017年至今,为研究渐趋成熟期。总体上看... 近四十年来,随着中国茶文化研究的日益深入,茶诗研究热度的上升,学界对宋代茶诗的关注和研究也逐渐增多。其研究历程大致可分为三个阶段:1984-2000年,为研究发轫期;2001-2016年,为研究蓬勃发展期;2017年至今,为研究渐趋成熟期。总体上看,近四十年来,宋代茶诗研究成果不算少,但还基本停留在茶诗名家研究,学科交叉研究如茶诗地理学研究还相对较少,茶诗的艺术性也还有待进一步深入探讨。未来宋代茶诗研究还可在宏观把握和系统梳理的基础上,进一步加强理论深度的挖掘,并充分利用交叉学科研究的优势,从多角度切入,进一步拓展、深入对宋代茶诗的研究。 展开更多
关键词 近四十年 宋代茶诗研究 阶段性特点
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Improving the Use of Insecticide-Treated Nets among Children under Five Years Old in Benin, West Africa
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作者 Emmanuel Houessou Tatchémè Filémon Tokponnon 《Advances in Infectious Diseases》 2023年第2期137-158,共22页
Background: In Benin, malaria represents the first cause of consultation and hospitalization (48% for children under 5 years old) in health units. It also accounts for 23.1% of deaths recorded in health facilities (Mo... Background: In Benin, malaria represents the first cause of consultation and hospitalization (48% for children under 5 years old) in health units. It also accounts for 23.1% of deaths recorded in health facilities (MoH, 2019). Between the two main components of vector control adopted by Benin government, the mass distribution campaigns of Insecticide-Treated Nets (ITNs) remained the only proven cost-effective way to rapidly achieve high and equitable coverage (WHO, 2017). After the fourth mass distribution campaign conducted in 2017, the Demographic and Health Survey (DHS) data indicated that the percentage of children who slept under an ITN has increased from 20% in 2006 to 70% in 2011-2012 and to 76% in 2017-2018 while the incidence of malaria (tested positive) is increasing rapidly among children under 5 years old, growing from 36.5% in 2009 to 28.8% in 2012 and then to 51.4% in 2019. This study aims to understand this contrast by identifying the origin of the increase in ITN use over time among children under five years old and the factors which determine this use. Methods: Data from the Demographic and Health Survey (DHS) conducted in Benin respectively in 2006 and in 20018 were used during the analysis, which covered 13,445 children under five years old from 2006 DHS and 12,255 children from 2017-2018 DHS. Firstly, the data were analyzed using decomposition method to highlight the origin of the increase of ITN use over time among children under five years old. Secondly, the chi-square test analysis estimated the association between ITN use and some characteristics (wealth index, maternal or caregiver education level and child age). Finally, the logistic regression model was used to identify the main factors, which influence the net use over the study period. Results: This study shows that the improvement of basic conditions is the main origin of behavior change in the use of ITNs among children under five years old. This improvement of the basic conditions consists of making ITNs available in households and informing household members about the benefits of ITN use. So, the free ITN distribution campaigns, routine distribution, awareness campaigns about the benefits of ITN use are the strategies, which increase the household capacities and knowledge, allowing household members to make their children sleep under net. The analysis also shows that region of residence, wealth index of household, household size, religion, and child age continue to determine the ITN use among children under age 5 years old and MNCP will integrate the factors in malaria prevention strategies in order to achieve universal use of ITNs. Conclusions: Although, sleeping under ITN behavior has indeed spread among children under 5 years old, policymakers and other stakeholders should design strategies to maintain and improve the current level of ITN use to reach the collective protection threshold (80% according to WHO). Therefore, to address the challenges of universal use of ITN, the study recommends expanding the routine distribution system to private sector health centers;discussing issues related to health service utilization (particularly ITN use) within a consultation framework at the communal level. In addition, collecting qualitative and quantitative data in the Oueme region will allow better understanding of all aspects of the ITN use gap among children under 5 years. 展开更多
关键词 MALARIA Long-lasting Insecticidal Net (LLIN) Child under 5 years Old Health Policy BENIN
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卵巢癌患者生辰五运六气特点与罹患率相关性分析
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作者 杨舒涵 冯婧丽 +7 位作者 谢伊 刘苏颖 王妍 方宇航 房立源 王润兮 隋白鹭 张英 《山东中医杂志》 2024年第9期965-969,共5页
目的:分析卵巢癌患者先天五运六气特点与分布差异,并研究其与后天发病的相关性。方法:选取2018年至2022年在中国中医科学院广安门医院就诊的卵巢癌患者共6 129例作为研究对象,分析卵巢癌患者出生日期运气学特征的分布差异,探讨其与卵巢... 目的:分析卵巢癌患者先天五运六气特点与分布差异,并研究其与后天发病的相关性。方法:选取2018年至2022年在中国中医科学院广安门医院就诊的卵巢癌患者共6 129例作为研究对象,分析卵巢癌患者出生日期运气学特征的分布差异,探讨其与卵巢癌罹患率的关系。结果:卵巢癌患者的出生日期在不同天干、主运、主气、客气、司天在泉分布方面存在显著差异性(P<0.05)。出生日期天干为癸年、主运为金运、主气为阳明燥金、客气为阳明燥金、司天在泉为阳明燥金司天-少阴君火在泉的人群更易罹患卵巢癌;出生日期天干为丁年、主运为火运、主气为少阴君火、客气为太阴湿土、司天在泉为太阴湿土司天-太阳寒水在泉的人群不易罹患卵巢癌。结论:卵巢癌的后天发病与先天运气学禀赋有一定相关性。 展开更多
关键词 五运六气 卵巢癌 出生日期 癸年 金运 阳明燥金 阳明燥金司天-少阴君火在泉
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《大年夜》中译本比较研究
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作者 郭育婷 《世界文学评论(高教版)》 2024年第2期161-164,共4页
樋口一叶是日本明治时期为数不多的女性作家之一,年仅24岁就因肺结核而去世。她的创作历程非常短暂,被称为“奇迹的十四个月”,但仍留下了《青梅竹马》《十三夜》《浊流》《大年夜》等著名短篇小说,以及众多日记、随笔、和歌。其中,《... 樋口一叶是日本明治时期为数不多的女性作家之一,年仅24岁就因肺结核而去世。她的创作历程非常短暂,被称为“奇迹的十四个月”,但仍留下了《青梅竹马》《十三夜》《浊流》《大年夜》等著名短篇小说,以及众多日记、随笔、和歌。其中,《大年夜》代表着她的创作风格由浪漫主义转向现实主义。本文将对分别由萧萧和林文月翻译的《大年夜》中译本从语言风格、文化内涵、译者的创造性翻译三方面进行对比,进而分析译者的翻译风格,探究翻译策略在日本文学汉译过程中的实践性与可靠性。 展开更多
关键词 《大年夜》 归化 异化 萧萧 林文月
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“带了镣铐的进军”:“且介亭杂文”的生成与艺术特征
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作者 张洁宇 《四川大学学报(哲学社会科学版)》 CSSCI 北大核心 2023年第2期30-37,188,189,共10页
鲁迅以“且介亭杂文”命名自己1934—1936年间的杂文,强调此间写作与“周围的情形”的密切关联。鲁迅用“且介亭”为题强调半租界的环境,不仅强调地理位置和文化环境上的杂糅与交叉,更强调资本市场与专制政府的合谋,尤其是其联手对革命... 鲁迅以“且介亭杂文”命名自己1934—1936年间的杂文,强调此间写作与“周围的情形”的密切关联。鲁迅用“且介亭”为题强调半租界的环境,不仅强调地理位置和文化环境上的杂糅与交叉,更强调资本市场与专制政府的合谋,尤其是其联手对革命文学进行的压制。在这样的压迫下,鲁迅的反抗也就具有了更明确的针对性和具体性。如何在“且介亭”中想方设法写出诗史般的杂文并使之与读者见面,如何“带着镣铐进军”,是鲁迅彼时最重要的任务。换句话说,“且介亭杂文”本身就是鲁迅在这一阶段反抗和突破文网的成果,它们既是“且介亭”处境的体现,也是这一处境的产物,因而独具一种特殊的历史意义与艺术特征。“且介亭杂文”一方面是“含胡”的,以迂回、智慧的斗争方式面对审查;另一方面,鲁迅在杂文和《故事新编》里都使用了借古论今的方式,取道历史而批判现实,这也成为其后期杂文的重要特征之一。 展开更多
关键词 鲁迅 且介亭 后期杂文 艺术特征
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The Impact of Malaria Control Interventions on Malaria and Anaemia in Children under Five after Ten Years of Implementation in the Hohoe Municipality of Ghana
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作者 Margaret Kweku Eric Kwaku Appiah +4 位作者 Yeetey Enuameh Martin Adjuik Wisdom Takramah Elvis Tarkang John Gyapong 《Advances in Infectious Diseases》 2017年第3期93-105,共13页
Background: Malaria remains a dominant health issue among children in Ghana. We monitored the trend of long lasting insecticide net (LLIN) ownership and use and its impact on malaria and anaemia among children under f... Background: Malaria remains a dominant health issue among children in Ghana. We monitored the trend of long lasting insecticide net (LLIN) ownership and use and its impact on malaria and anaemia among children under five over the past decade in an area of intense, prolonged and seasonal malaria transmission. Methods: A total of 1717, 2155 and 1915 children were surveyed in June and 1717, 2155 and 1697 in November in 30 communities of the Hohoe Municipality in 2006, 2010 and 2015 respectively. The primary outcomes monitored were the trend of LLIN ownership, use and prevalence of malaria and anaemia through cross-sectional surveys. Findings: Results showed a significantly positive trend (p Interpretation: Ownership of LLIN and its use together with other indicators of malaria prevalence generally improved five years after the implementation of a malaria control programme. Ten years after programme implementation, consistent improvement was only in LLIN ownership and use. Also malaria prevalence indicators improved in the post as compared to the pre-rainy season in the study communities. 展开更多
关键词 MALARIA ANAEMIA Long lasting Insecticide Treated BedNets CHILDREN under FIVE yearS Hohoe MUNICIPALITY Ghana
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百年互动与制度变迁——中国百年农村土地制度变革逻辑新解
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作者 陈胜祥 冷超 +1 位作者 邹勇文 涂小松 《江西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2023年第1期126-136,共11页
从体、相、用三位一体的角度定义制度和制度变迁,构建一个能够反映中国共产党和农民长期互动的分析框架,用以探究中国百年农村土地制度变革逻辑,结果显示:(1)在资源稀缺、有限理性和制度受众分化等社会基本事实的约束下,中国共产党需要... 从体、相、用三位一体的角度定义制度和制度变迁,构建一个能够反映中国共产党和农民长期互动的分析框架,用以探究中国百年农村土地制度变革逻辑,结果显示:(1)在资源稀缺、有限理性和制度受众分化等社会基本事实的约束下,中国共产党需要持续保持和农民的良性互动,才能有效缓解知识不完备对改革的不良影响,进而解决利益难协调和共识难达成等两个衍生难题;(2)百年史实表明,中国共产党和农民一共有过四次较为强烈的互动,中国共产党逐步认清农民的土地利益诉求,择取其正确的发展观念对制度进行修正,成功推动土地制度变迁;(3)中国共产党和农民的互动,是农村土地制度变革阶段形成的重要原因,依据互动内容,可对百年土地制度变革阶段进行新的划分。由此启示:中国百年农村土地制度变革之所以获得成功,根本原因在于中国共产党自始至终和农民保持良性互动,有效降低知识不完备及其衍生难题对土地制度改革的不良影响。 展开更多
关键词 农村土地制度变迁 中国共产党 农民群众 百年互动 长期分析框架
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近百年气候变暖的不确定性分析 被引量:24
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作者 赵宗慈 王绍武 +1 位作者 罗勇 江滢 《科技导报》 CAS CSCD 北大核心 2009年第23期41-48,共8页
百年时间尺度全球和中国气候变暖存在不确定性,以中国为例,前50年观测资料不足可能造成百年变暖趋势的不确定性,后50年城市化进程热岛效应可能在增暖中占到25%。贡献于近50年中国气候的变暖,不仅来自人类排放增加,而且城市化,气温自然... 百年时间尺度全球和中国气候变暖存在不确定性,以中国为例,前50年观测资料不足可能造成百年变暖趋势的不确定性,后50年城市化进程热岛效应可能在增暖中占到25%。贡献于近50年中国气候的变暖,不仅来自人类排放增加,而且城市化,气温自然的准周期性和年代际变率,地面接收太阳辐射的减少(变暗)或增加(变明),以及其他外部强迫如火山活动和太阳活动与气候系统内部作用等。全球气候模式的不确定性和未来情景设计中的问题都将影响对变暖的原因分析,并使得10~20年预测的可信度较低。这些问题有待进一步研究解决。 展开更多
关键词 百年时间尺度 气候变暖 不确定性
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从中国过去2000年温度变化看20世纪增暖 被引量:33
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作者 郑景云 葛全胜 方修琦 《地理学报》 EI CSCD 北大核心 2002年第6期631-638,共8页
以重建的过去2000年中国东部地区冬半年温度距平序列为基础资料,从温暖程度、冷暖变化速率和历史相似型3个方面,对20世纪增暖在过去2000年中的位置予以了详细分析。结果发现:虽然20世纪暖期的温暖程度非常明显,但至目前为止,其温暖程度... 以重建的过去2000年中国东部地区冬半年温度距平序列为基础资料,从温暖程度、冷暖变化速率和历史相似型3个方面,对20世纪增暖在过去2000年中的位置予以了详细分析。结果发现:虽然20世纪暖期的温暖程度非常明显,但至目前为止,其温暖程度和波动幅度均没有超过过去2000年曾经出现过的最高水平。20世纪增暖实质上是气候从寒冷阶段(小冰期)向温暖阶段转变的快速升温过程,速率虽非常大(1.1℃/100年),但这一升温过程与过去2000年中其它气候由寒冷阶段向温暖阶段转变的过程相似,并不是唯一的。其中从百年际波动看,20世纪暖期的温度距平不但低于中世纪暖期后期温暖时段(1200's~1310's),也低于隋唐暖期(570's~770's) 及中世纪暖期前期的温暖时段(930's~1100's);从30年际变化看,20世纪暖期最暖30年的温度距平低于中世纪暖期的最暖30年,而与隋唐暖期的最暖30年相当;从年代际变化看,20世纪最暖年代的温度距平与中世纪暖期前期的最暖年代极为接近。另外,从中国过去2000年的冷暖阶段变化过程看,20世纪暖期的最可能相似型为隋唐暖期(570's^770'sAD),而不是中世纪暖期。同时可能是由于受到1950's以后因人类活动导致的温室效应作用日益增大的影响,1980's以后的升温速率明显加快。 展开更多
关键词 温度变化 20世纪 中国 气候变化 人类活动 温室气体
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中国过去2000年气候变化的评估 被引量:73
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作者 郑景云 王绍武 《地理学报》 EI CSCD 北大核心 2005年第1期21-31,共11页
根据近20年中国在过去2000年气候变化研究领域的主要文献,对中国(特别是中国东部)过去2000年气候变化进行了综合评估。主要结论有(1)在中国东部,虽然20世纪暖期的温暖程度非常明显,但至目前为止的研究结果显示,其温暖程度和波动幅度可... 根据近20年中国在过去2000年气候变化研究领域的主要文献,对中国(特别是中国东部)过去2000年气候变化进行了综合评估。主要结论有(1)在中国东部,虽然20世纪暖期的温暖程度非常明显,但至目前为止的研究结果显示,其温暖程度和波动幅度可能尚未超过过去两千年曾经出现过的最高水平。(2)中国东部降水同样存在数百年的趋势变化,且存在明显的区域差异,特别是华北与江南的低频变化趋势几乎相反。就东部地区的总体变化趋势而言280'sAD以前,相对湿润;自280'sAD开始,逐渐变干;而至1230'sAD以后,则维持在一个相对较干的水平上。(3)中国西部的温度变化趋势与东部基本一致,但中世纪暖期与小冰期不如东部明显。(4)中世纪暖期,中国东部的华北地区相对干旱,江南则相对湿润;而在小冰期,华北地区则相对湿润,且整个东部地区的降水变率增大。 展开更多
关键词 中国 气候变化 过去2000年 气温变化 降水变化 中世纪暖期 小冰期
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青海湖近600年的水位变化 被引量:40
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作者 冯松 汤懋苍 周陆生 《湖泊科学》 EI CAS CSCD 2000年第3期205-210,共6页
根据王苏民 [4 ] 给出的青海湖深水区重力岩芯的密集采样结果 ,重建了青海湖近60 0年的水位变化 .发现水位变化与降水关系密切 ,水位的升降时段与降水的丰枯时段相对应 .60 0年来青海湖区的环境变化有
关键词 青海湖 水位变化 气候变化
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2000—2010年中国三北地区生态系统时空变化特征 被引量:20
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作者 黄麟 曹巍 +1 位作者 巩国丽 赵国松 《生态学报》 CAS CSCD 北大核心 2016年第1期107-117,共11页
基于遥感解译反演、模型模拟估算等方法,以地面调查作为主要验证手段,分析了21世纪前10年我国三北地区生态系统宏观结构、质量及关键服务变化状况及其驱动因素。结果表明:(1)2000—2010年,三北地区林地面积净增加了0.69万km2,草地面积... 基于遥感解译反演、模型模拟估算等方法,以地面调查作为主要验证手段,分析了21世纪前10年我国三北地区生态系统宏观结构、质量及关键服务变化状况及其驱动因素。结果表明:(1)2000—2010年,三北地区林地面积净增加了0.69万km2,草地面积减少了0.13万km2,湿地面积净减少0.21万km2,耕地面积减少了0.87万km2,人工表面增加了0.57万km2,其它类型面积持续减少了496.5km2。(2)近10年,三北地区归一化植被指数(NDVI)、叶面积指数(LAI)、地上植被生产力总体呈现轻微增加趋势,特别是黄土高原丘陵沟壑区,然而植被覆盖度总体呈现微弱减少趋势。(3)近10年,三北地区单位面积土壤风蚀模数下降了27.25%,减少速率为每年1.13t/hm2,由于风蚀力逐年减弱导致防风固沙服务量呈现减弱趋势。三北地区水蚀区近10年土壤水蚀模数总体呈现微弱增加趋势,而黄土高原区和风沙区则呈现降低趋势,生态系统单位面积土壤保持服务量呈现增加趋势,年增速0.28t/hm2,说明土壤保持能力有所提高。(4)三北地区近10年气温变化斜率为0.02℃/a,适度增温、降水量增加有利于植被恢复;东北华北平原农区和黄土高原丘陵沟壑区人类负向扰动指数呈现减少趋势,说明人类活动对这两个区域自然生态系统的扰动有所遏制。 展开更多
关键词 三北地区 生态系统 时空格局 十年变化 遥感
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基于历史文献重建的近2000年中国温度变化比较研究 被引量:21
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作者 郑景云 葛全胜 +1 位作者 方修琦 张学珍 《气象学报》 CAS CSCD 北大核心 2007年第3期428-439,共12页
文中对不同学者利用不同来源中国历史文献资料重建的温度变化代用序列进行了比对,分析了同一地区不同序列之间及不同地区间序列的异同,以及造成这些异同的主要原因。结果表明:(1)不同学者重建的同一地区温度(或冷暖)变化序列具有较高的... 文中对不同学者利用不同来源中国历史文献资料重建的温度变化代用序列进行了比对,分析了同一地区不同序列之间及不同地区间序列的异同,以及造成这些异同的主要原因。结果表明:(1)不同学者重建的同一地区温度(或冷暖)变化序列具有较高的相似性;不同学者所估计的30 a平均温度相对变幅完全一致(即在99.9%置信水平下,二者通过无显著性差别的检验)的时段平均占所有时段的73.4%,还有8.6%的时段虽在幅度大小上有差异但冷暖定性一致,二者共计占82%。(2)不同地区间的温度变化序列也具有较高的相关性,且重建区域相距越近其相关系数也越高,序列的相似程度也越大;而不同学者所选择的重建方法与代用指标不同并不影响不同地区之间序列的相似程度,说明不同地区序列的不一致应是由于地区的气候变化差异造成的。(3)虽然不同学者所估计的中国过去千年以上的温度变化趋势及波动幅度等存在一定差异,但各家所揭示的中国东部过去2000年主要冷暖阶段的出现时间则基本一致。这些结果进一步说明:以前学术界对各家序列差异的认识可能并没有或很少考虑地区间气候变化的差异,因而夸大了不同学者因重建方法与原始证据不同而造成的重建结果差异,这是不客观的。 展开更多
关键词 历史文献资料 近2000年 中国温度变化 比对分析
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