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Spatiotemporal variations of aridity in China during 1961–2015: decomposition and attribution

Science Bulletin 2018年第18期63卷 1187-1199页

作者： Chang Liu Wei Huang Song Feng Jianhui Chen Aifeng Zhou Key Laboratory of Western China's Environmental Systems (Ministry of Education). College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Department of Geosciences University of Arkansas Fayetteville AR 72703 USA

Changes in global climate intensify the hydrological cycle, directly influence precipitation, evaporation,runoff, and cause the re-distribution of water resources in time and space. The aridity index (AI), defined as the ratio of annual precipitation to annual potential evapotranspiration, is a widely used numerical indicator to quantify the degree of dryness at a given location. This study examined the effects of climate change on AI in China during 1961–2015. The results showed that the nationally averaged AI experienced a notable interdecadal transition in 1993, characterized by increasing AI (wetter) between 1961 and 1993,and decreasing AI (drier) after 1993. Overall, the decreased solar radiation (solar dimming) was the main factor affected the nationally averaged AI during 1961–1993, while the relative humidity dominated the variations of nationally averaged AI during 1993–2015. However, the roles of individual factors on the changes in AI vary in different subregions. Precipitation is one of the important contributing factors for the changes of AI in almost all subregions, except the Mid-Lower Yangtze and Huaihe basins. Solar radiation has been significantly decreased during 1961–1993 in South China, Southwest China, Mid-Lower Yangtze and Huaihe basins, and the Tibetan Plateau. Therefore, it dominated the trends of AI in these subregions.The relative humidity mainly affected the Mid-Lower Yangtze and Huaihe basins, Southwest China, and the Tibetan Plateau during 1993–2015, hence dominated the trends of AI in these subregions. The changes of temperature and wind speed, however, played a relatively weak role in the variations of AI.

关键词：土壤水分蒸发蒸腾损失总量中国干旱时间空间分解相对湿度全球气候

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Investigating natural drivers of vegetation coverage variation using MODIS imagery in Qinghai, China

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Journal of Arid Land 2016年第1期8卷 109-124页

作者： zhou Lei LYU aifeng China National Environmental Monitoring Center Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The climatically sensitive Qinghai province of China has been recognized as a hotspot for studies on the feedbacks of terrestrial ecosystems to global climate change. Thus, investigating vegetation coverage and its natural drivers in Qinghai is an important focus of ecosystem research. On the basis of Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) time series data, we estimated the vegetation coverage in this region using the dimidiate pixel model. Trend analyses, correlations between meteorological parameters, changes in vegetation coverage, and the temporal and spatial relationships between soil texture and vegetation coverage were used to investigate the possible drivers of vegetation coverage variations. The results indicated that the reduction of vegetation coverage slowed down in the period from 2000 to 2012. Annual mean temperature was the main climatic driver of the total extremely low and low vegetation coverage areas in Qinghai, followed by the precipitation anomalies. The extremely low and low vegetation coverage areas were mainly distributed in regions with a mean annual relative air humidity of <40% and the spatial distributions of these two area types differentiated along the 200-mm rainfall contours. The total extremely low and low vegetation coverage areas were mainly characterized by sandy clay loam soil, followed by loamy sand and sandy soil. Regions with sandy loam or loam soil have the greatest risk of vegetation coverage reductions. Knowledge of vegetation coverage variation and its natural drivers in the ecologically fragile region of Qinghai can provide scientific support for managing environmental change and desertification.

关键词： vegetation coverage remote sensing MODIS climate change

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Emergence of ancient cities in relation to geopolitical circumstances and climate change during late Holocene in northeastern Tibetan Plateau, China

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Frontiers of Earth Science 2016年第4期10卷 669-682页

作者： Guanghui DONG Honggao LIU Yishi YANG Ying YANG Aifeng Zhou Zhongxin WANG XiaoyanREN Fahu CHEN Key Laboratory of Western China's Environmental Systems (Ministry of Education) College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China College of Agronomy and Biotechnology Yunnan Agricultural University Kunming 650201 China Qinghai Provincial Institute of Cultural Relics and Archaeology Xining 810007 China

The study of the history of human activities in ancient cities has provided valuable evidences for under- standing the evolution of human-land relations during the late Holocene. Numerous ancient cities were discovered through archaeological surveys of the east Qinghai Province, located on the northeastern border of the Tibetan Plateau, China; however, the mystery of when or why these cities were built remains unsolved. As recorded in this paper, we sampled reliable dating materials from 47 ancient cities in the area, determined their ages by radiocarbon dating, and compared the dating results with historical documents and high resolution paleoclimate records to explore the influencing factors for the develop- ment of these ancient cities. The 54 radiocarbon dates indicated that most of these cities were built or repaired during the Han Dynasty （202 BC-AD 220）, Tang Dynasty （AD 618-AD 907）, the Five Dynasties and Ten Kingdoms period （AD 907-AD 960）, the Song dynasty （AD 960-AD 1279）, and the Ming Dynasty （AD 1368-AD 1644）. The radiocarbon dates correspond well with historical records of the area. Our work suggests the ancient cities in east Qinghai Province were likely built primarily for military defense, and may have also have been affected by climate change.

关键词： radiocarbon dating ancient city historicrecords war climate change

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Reliability of radiocarbon dating on various fractions of loess-soil sequence for Dadiwan section in the western Chinese Loess Plateau

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Frontiers of Earth Science 2014年第4期8卷 540-546页

作者： Zongli WANG Hui ZHAO Guanghui DONG Aifeng Zhou Jianbao LIU Dongju ZHANG MOE Key Laboratory of West China's Environmental System Lanzhou University Lanzhou 730000 China Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The accurate radiocarbon dating of loess-soil sequences plays an essential role in the reconstruction of the environmental and climatic changes in continental settings during the last glaciation and Holocene. However, our knowledge about the reliability of radiocarbon ages of various fractions of soil and loess samples is still insufficient. Here, we present our study results on radio- carbon ages based on bulk organic matter, humin fraction, and carbonate of samples collected from a loess-paleosol section in the western Chinese Loess Plateau. We compare these observations with the optically stimulated luminescence ages and charcoal radiocarbon ages to evaluate the reliability of these fractions. We observed that the radio- carbon ages of humin fraction are very close to those of charcoal and are consistent with the optically stimulated luminescence ages within the experimental errors. We observed a significant deviation in the radiocarbon ages of carbonate and bulk organic matter from those of charcoal and optically stimulated luminescence ages, likely due to the dilution of these fractions during the pedogenetic process. Our results reveal that, except for charcoal, the humin fraction may yield reliable laC ages for the Chinese loess-soil sequence.

关键词： loess-soil sequence humin fraction charcoal,organic matter radiocarbon dating

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Multiple evidences indicate no relationship between prehistoric disasters in Lajia site and outburst flood in upper Yellow River valley, China

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Science China Earth Sciences 2018年第4期61卷 441-449页

作者： DONG GuangHui ZHANG FanYu LIU FengWen ZHANG DongJu zhou aifeng YANG YiShi WANG GongHui MOE Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou University Key Laboratory of Mechanics on Disaster and Environment in Western China (Ministry of Education) Department of Geological EngineeringLanzhou University Research Center on Landslides Disaster Prevention Research InstituteKyoto University

All around the world, ancient legends exist about the Great Flood, and the influence of the Great Flood in human evolutionary history is a hotly debated topic. In China, the legend of the prehistoric Great Flood and Yu the Great's flood control has a long history and is considered to be closely linked to the establishment of the Xia Dynasty. However, there is a lack of solid scientific evidence. Against this issue, some scholars have proposed that an earthquake around 1920 BCE in the Guanting Basin along the upper reaches of the Yellow River led to the creation of a lake by damming in the Jishi Gorge and that the outburst of water from that lake led to the massive flood in the Yellow River region. These studies provided new scientific evidence for the Chinese legend. In this paper, we date skeletal samples embedded in earthquake sand blasting from the Lajia site, analyze remains from natural disasters(such as earthquakes and floods) and also archaeological remains. In addition, we compared the skeletal samples dating with that of sediments from the dammed-up lake. Our results are inconsistent with those of previous scholars. The earthquake at the Lajia site occurred no earlier than 1800 BCE, and the dammed-up lake in Jishi Gorge had disappeared by 3600 BCE. Thus, the formation and outburst of the dammed lake, the sudden death of ancient humans at the Lajia site and the ancient earthquake were independent events occurring at different times. In addition, the massive flood in the upper reaches of the Yellow River did not actually happen. Thus, we argue against and invalidate the hypothesis that the massive flood was related to Yu the Great's flood control and the establishment of the Xia Dynasty.

关键词：科学证据大洪水自然灾难黄河爆发地点中国山谷

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Effects of climate change and human activity on lake shrinkage in Gonghe Basin of northeastern Tibetan Plateau during the past 60 years

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Journal of Arid Land 2016年第4期8卷 479-491页

作者： WU Duo CHEN Fahu LI Kai XIE Yaowen ZHANG Jiawu zhou aifeng College of Earth and Environmental Sciences MOE Key Laboratory of Western China's Environmental SystemsLanzhou University

Changes in the status of freshwater resources are a topic of major global, regional and local concern. This is especially so in the arid and semi-arid regions of China, where shortage of water resources plays a crucial role in limiting sustainable socioeconomic development, as well as in sustaining natural ecosystems. Recent climate change, as well as the effects of localized human activity, such as the use of water for irrigation agriculture, may have significant effects on the status of the water resources in the region. Here, we report the results of a study of changes in the areas of lakes in Gonghe Basin, northeastern Tibetan Plateau of China, over the last 60 years. The data were acquired from optical satellite images and demonstrate that the total water area of lakes in Gonghe Basin decreased significantly from the 1950s to 1980s. The cause is ascribed mainly to human activity including exploitation of farmland, against a background of increasing population; in addition, climatic data for the region demonstrate a minor drying trend during this period as the temperature increased slightly. After the construction of several reservoirs, significant amounts of water were redistributed to promote irrigation agriculture and we conclude that this caused a significant shrinkage of the natural lakes. However, both the area of farmland and the population size remained approximately constant after 1990. We conclude that the variation of the total area of lakes during the second period was mainly controlled by climatic factors （precipitation and temperature）. As the regional temperature reached a new high, the area of some of the lakes decreased sharply before finally maintaining a relatively steady state. We emphasize that anthropogenic climate change and human activity have both significantly influenced the status of water resources in the arid and semi-arid regions of China.

关键词： Gonghe Basin lake shrinkage climate change human activity

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炎症性肠病患者心理韧性与自我管理行为、疾病进展恐惧的相关性分析

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中华现代护理杂志 2022年第27期28卷 3751-3755页

作者：周冬梅臧丽李苗苗阮爱超张青王爱凤南京医科大学附属淮安第一医院消化内科淮安223300 南京医科大学附属淮安第一医院骨科淮安223300 南京医科大学附属淮安第一医院护理部淮安223300

目的探讨炎症性肠病患者心理韧性与自我管理行为、疾病进展恐惧的相关性,为患者的临床治疗和护理提供参考依据。方法采用便利抽样法,选取2020年1月—2021年12月在南京医科大学附属淮安第一医院消化内科住院的141例炎症性肠病患者为研究... 详细信息

目的探讨炎症性肠病患者心理韧性与自我管理行为、疾病进展恐惧的相关性,为患者的临床治疗和护理提供参考依据。方法采用便利抽样法,选取2020年1月—2021年12月在南京医科大学附属淮安第一医院消化内科住院的141例炎症性肠病患者为研究对象,采用基本信息调查表、炎症性肠病病人自我管理行为量表、心理韧性量表、恐惧疾病进展简化量表对其进行问卷调查。结果141例炎症性肠病患者自我管理行为量表、心理韧性量表、恐惧疾病进展简化量表总分分别为(126.69±26.67)、(67.65±12.52)、(30.25±9.23)分;Pearson相关分析结果显示,炎症性肠病患者的心理韧性量表总分与恐惧疾病进展简化量表总分呈负相关(r=-0.68,P<0.05),自我管理行为量表总分与恐惧疾病进展简化量表总分呈负相关(r=-0.52,P<0.05),心理韧性量表总分与自我管理行为量表总分呈正相关(r=0.72,P<0.05)。结论炎症性肠病患者心理韧性和自我管理行为均与疾病进展恐惧呈负相关。医护工作者可通过制订相关干预策略增强患者心理韧性,提高其疾病自我管理水平,从而有效降低其疾病进展恐惧水平。

关键词：炎症性肠病自我管理心理韧性恐惧疾病复发

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Climatic changes documented by stable isotopes of sedimentary carbonate in Lake Sugan,northeastern Tibetan Plateau of China,since 2 kaBP

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Chinese Science Bulletin 2005年第17期50卷 1930-1939页

作者： QIANG Mingrui CHEN Fahu ZHANG Jiawu GAO Shang-yu zhou aifeng China Center of Desert Research at Beijing Normal University and Key Laboratory of Environmental Changes and Natural Disaster Ministry of Education of China Beijing Normal University Beijing 100875 China Center for Arid Environment and Paleoclimate Research (CAEP) Natiunal Laboratory of Western China's Environmental System Ministry of Education of China Lanzhou University Lanzhou 730000 China

Lake Sugan at the northern edge of the Qaidam Basin was selected as the research object. The temporal se-quence of sedimentary cores retrieved from Lake Sugan since 2 kaBP was reconstructed using the 210Pb, AMS 14C and conventional 14C dating methods. Carbon and oxygen iso-topes of carbonate in the fine-grained lake sediments were analysed. Combined with the changes of δ 18O values of sur-face water and air temperature observation data in the study area, it might be thought that the δ 18O value of the carbon-ate indicates effective moisture, and the changes in δ 13C val-ues are related to annual freeze-up duration of the lake and indirectly indicate air temperature changes in winter half year. From the above, the sequence of climatic changes in the region since 2 kaBP was established. The climatic changes experienced five stages: Warm-dry climate during 0-190 AD; cold-dry climate during 190-580 AD; warm-dry cli-mate during 580-1200 AD (MWP); cold-wet climate during 1200-1880 AD (LIA); cold-dry climate during 1880-1950 AD; and climate warming since 1950s. The air temperature changes in winter half year reflected by carbon isotope since 2 kaBP are in good agreement with the historical literature records and other geologic records, which shows that the climate changes recorded by the stable isotopes from Lake Sugan since 2 kaBP are of universal significance.

关键词：气候变化同位素稳定性碳酸盐沉积作用青藏高原

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工业互联网关键技术及部署实施探讨

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电信快报 2022年第9期 6-10,15页

作者：乔爱锋周俊伟中通服咨询设计研究院有限公司江苏省南京市210019 中国电信股份有限公司苏州分公司江苏省苏州市215004

在新一代信息通信技术与制造技术深度融合的背景下,工业互联网技术体系及关键技术已成为基础设施要素升级和集成创新的重要支撑,驱动生产经营、业务形态与组织管理方式的全方位变革重构。基于我国工业互联网的发展现状和产业共识,提出... 详细信息

在新一代信息通信技术与制造技术深度融合的背景下,工业互联网技术体系及关键技术已成为基础设施要素升级和集成创新的重要支撑,驱动生产经营、业务形态与组织管理方式的全方位变革重构。基于我国工业互联网的发展现状和产业共识,提出工业互联网功能体系架构及技术发展趋势,阐述关键基础设施端到端部署框架及实施方案,分析“5G+工业互联网”融合应用发展和典型应用场景,对未来关键技术的研究重点和应用创新给出建议。

关键词：工业互联网体系架构关键技术部署实施

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孢粉浓缩物在AMS 14C测年研究中的应用及展望

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第四纪研究 2021年第1期41卷 136-145页

作者：张姚崔巧玉周爱锋中国科学院地理科学与资源研究所中国科学院陆地表层格局与模拟重点实验室北京100101 兰州大学资源环境学院西部环境教育部重点实验室甘肃兰州730000

可靠的14C测年材料是建立高精度年代序列的前提。在陆生植物残体缺乏的沉积类型中或某一沉积层位,利用其他14C测年材料可能会影响测年结果的精度。而陆生植物孢粉广泛存在于各类地质载体中,利用其浓缩物定年是解决这一问题的途径之一。... 详细信息

可靠的14C测年材料是建立高精度年代序列的前提。在陆生植物残体缺乏的沉积类型中或某一沉积层位,利用其他14C测年材料可能会影响测年结果的精度。而陆生植物孢粉广泛存在于各类地质载体中,利用其浓缩物定年是解决这一问题的途径之一。文章综述了不同沉积类型孢粉浓缩物的提取方法及其测年结果的验证;成功提取了秦岭太白山高山湖泊大爷海表层沉积物中的孢粉浓缩物,其AMS14C定年结果与全有机质年代对比表明高山封闭湖泊孢粉浓缩物能够提供较为可靠的年代估计且在一定程度上能避免碳库效应的影响;但仍需对湖泊岩芯多个层位开展多种测年材料(如陆生植物残体、炭屑、有机质)的对比定年研究以做进一步验证。基于前人及本研究提取经验,归纳总结出适用于湖泊沉积、泥炭沉积、黄土-古土壤序列以及冰楔冰中孢粉浓缩物的提取流程,主要分为前期的孢粉富集(酸碱法)和后期的纯化处理(化学法、镜下挑选与重液浮选),并梳理了目前孢粉浓缩物在定年应用中需要注意的问题。探索沉积物孢粉浓缩物提取的新方法、改进并简化其现有提取流程、提高孢粉浓缩物提取效率(短时间内获取足量的、高含量的陆生植物孢粉),将极大地促进孢粉浓缩物定年方法在晚第四纪年代研究中的应用。

关键词：碳十四测年孢粉浓缩物提取方法

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