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史前人类探索、适应和定居青藏高原的历程及其阶段性讨论 被引量:19
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作者 陈发虎 夏欢 +3 位作者 高玉 张东菊 杨晓燕 董广辉 《地理科学》 CSSCI CSCD 北大核心 2022年第1期1-14,共14页
系统梳理了近年来的考古发现与研究成果,总结出人类向青藏高原扩散直至定居的5个阶段性发展过程:古老型智人自中更新世晚期就开始了对高原的适应;现代智人于40~30 ka前已经开启了对高原腹地的探索;末次冰消期以来的气候转暖时段,细石器... 系统梳理了近年来的考古发现与研究成果,总结出人类向青藏高原扩散直至定居的5个阶段性发展过程:古老型智人自中更新世晚期就开始了对高原的适应;现代智人于40~30 ka前已经开启了对高原腹地的探索;末次冰消期以来的气候转暖时段,细石器人群向高原大范围扩散,并在全新世早中期的活动更为频繁;粟作农业人群至少在5.2 ka前进入高原东部低海拔的河谷地带,在4.8 ka以后开始定居在高原东部3 000 m以上海拔的区域;3.5 ka以来麦作的传入和牧业经济的发展助力人群大规模定居高海拔区域。人类在向高原扩散和定居的过程中经历了漫长的生理与文化适应,但受限于当前考古发现与研究材料,史前狩猎采集、农业和牧业等人群在高原的时空分布、对高海拔环境的生理与行为适应﹑与低海拔人群和以藏族为主的现代高原人群之间的联系,以及高寒地区河谷农业和山地高原面游牧双重经济活动对高寒文明形成的支撑作用和高寒文明的普适性等问题仍需要深入研究,期待未来多学科交叉融合共同推动对这些问题的理解。 展开更多
关键词 青藏高原 极端环境 人类适应 环境考古 人类活动历史
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Holocene Moisture Variation Recorded by Aeolian Sand-Palaeosol Sequences of the Gonghe Basin, Northeastern Qinghai-Tibetan Plateau, China 被引量:7
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作者 LIU Bing ZHAO Hui +1 位作者 JIN Heling chen fahu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第3期668-681,共14页
The northeastern Qinghai-Tibetan Plateau(QTP) of China is located at the triple junction of the Asian winter and summer monsoons and the westerlies, where paleoclimatic evolution has an important scientific significan... The northeastern Qinghai-Tibetan Plateau(QTP) of China is located at the triple junction of the Asian winter and summer monsoons and the westerlies, where paleoclimatic evolution has an important scientific significance for recognizing the spatial-temporal pattern of Asian monsoons in the past and predicting environmental change in the future. Nevertheless, the framework of the Holocene moisture variation and related mechanisms remain controversial, owing to complex hydroclimatic conditions triggered by the landform of the large mountain-arid basin. Here, we employed geochemical proxies from typical aeolian sand-palaeosol sequences in the Gonghe Basin, northeastern QTP, together with Optically Stimulated Luminescence(OSL) dating, to reconstruct the pattern of effective moisture variation and associated mechanisms in this region. Our results indicate that the regional effective moisture was at its lowest until 9–8 ka, and approached a maximum during 8–4/3 ka of the middle Holocene. Afterwards, the climate became relatively dry in general, but with a transient humid interval around 2–1 ka. Our geochemical evidence indicates that the dry early Holocene probably can be attributed to a strong winter monsoon forced by remnant ice sheet, combined with the high evaporation caused by solar insolation. Also, shifts of humid-dry are closely linked to the Asian summer monsoonal strength and therefore the balance of evaporation-precipitation in the middle and late Holocene. Thus, the pattern of the Holocene effective moisture variation is characterized as the ‘monsoon model’ in a closed intermontane arid and semi-arid basin near the western Asian monsoonal limit. 展开更多
关键词 effective moisture geochemical analysis aeolian deposits HOLOCENE Gonghe Basin
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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 被引量:7
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作者 WU Duo chen fahu +3 位作者 LI Kai XIE Yaowen ZHANG Jiawu ZHOU Aifeng 《Journal of Arid Land》 SCIE CSCD 2016年第4期479-491,共13页
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 crucia... 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. 展开更多
关键词 Gonghe Basin lake shrinkage climate change human activity
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Special Issue Devoted to the Civilization and Environment along the Ancient Silk Road Preface 被引量:1
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作者 chen fahu DONG Guanghui +2 位作者 chen Jianhui HUANG Wei chen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第3期I0001-I0006,共6页
Trans-Eurasian exchange along the Ancient Silk Road The Ancient Silk Road was the major passageway for linking China,Central and West Asia,and Europe between the second century BCE(Before Common Era)and the sixteenth ... Trans-Eurasian exchange along the Ancient Silk Road The Ancient Silk Road was the major passageway for linking China,Central and West Asia,and Europe between the second century BCE(Before Common Era)and the sixteenth CE,which is identified as the center of civilizations in the Old World during that period(Frankopan,2015). 展开更多
关键词 SILK LINKING PASSAGE
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1949—2019年中国自然地理学与生存环境应用研究进展 被引量:53
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作者 陈发虎 吴绍洪 +23 位作者 崔鹏 蔡运龙 张镱锂 尹云鹤 刘国彬 欧阳竹 马巍 杨林生 吴铎 雷加强 张国友 邹学勇 陈晓清 谈明洪 王训明 包安明 程维新 党小虎 韦炳干 王国梁 王五一 张兴权 刘晓晨 李生宇 《地理学报》 EI CSSCI CSCD 北大核心 2020年第9期1799-1830,共32页
自然地理学是一门以基础研究见长的自然科学,其研究对象是与人类生存和发展密切相关的自然环境。中国的自然环境复杂多样,自然地理学家根据国家需求和区域发展在应用基础和应用研究方面同样取得显著成效,为国家重大经济建设、社会发展... 自然地理学是一门以基础研究见长的自然科学,其研究对象是与人类生存和发展密切相关的自然环境。中国的自然环境复杂多样,自然地理学家根据国家需求和区域发展在应用基础和应用研究方面同样取得显著成效,为国家重大经济建设、社会发展的规划,宏观生态系统与资源环境保护及区域可持续发展做出了重要贡献。本文总结了1949—2019年中国自然地理学在自然环境区域差异与自然区划、土地利用与覆被变化、自然灾害致灾因子和风险防控、荒漠化过程与防治、黄淮海中低产田改造、冻土区工程建设、地球化学元素异常和地方病防治、自然地理要素定位观测、地理空间分异性识别和地理探测器等方面的实践与应用,指出了未来自然地理学的应用研究方向。 展开更多
关键词 自然地理学 科学实践 应用研究 区域发展 国家战略
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中国地理科学学科体系浅析 被引量:40
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作者 陈发虎 李新 +3 位作者 吴绍洪 樊杰 熊巨华 张国友 《地理学报》 EI CSSCI CSCD 北大核心 2021年第9期2069-2073,共5页
新的国际和国内形势为地理科学带了新的发展机遇,同时也提出了更高的要求。以《中国学科及前沿领域发展战略研究(2021—2035)》地理科学的学科规划为契机,本文系统梳理了新时期地理科学的学科体系。根据地理科学现状和发展趋势,中国地... 新的国际和国内形势为地理科学带了新的发展机遇,同时也提出了更高的要求。以《中国学科及前沿领域发展战略研究(2021—2035)》地理科学的学科规划为契机,本文系统梳理了新时期地理科学的学科体系。根据地理科学现状和发展趋势,中国地理科学可划分为综合地理学、自然地理学、人文地理学和信息地理学4个二级学科,各二级学科下的三级学科也基本成熟,有些三级学科下的四级学科名称也在普遍使用。我们希望以这一新的学科体系为支点,完善地理科学的学科分支,推动地理科学框架下新兴学科的发展,更好地服务于新时期国际及国家的战略需求。 展开更多
关键词 地理科学 综合地理学 自然地理学 人文地理学 信息地理学 学科体系
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亚洲中部干旱区气候变化与丝路文明变迁研究:进展与问题 被引量:22
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作者 陈发虎 董广辉 +5 位作者 陈建徽 郜永祺 黄伟 王涛 陈圣乾 侯居峙 《地球科学进展》 CAS CSCD 北大核心 2019年第6期561-572,共12页
亚洲中部干旱区是对全球气候变化响应最为敏感的地区之一,也是水文变化剧烈和生态环境脆弱的地区。该地区包括了古丝绸之路的主体,在东西方交流和丝路文明兴衰历史中发挥了关键的作用。科学评估全球增温背景下亚洲中部干旱区人类社会可... 亚洲中部干旱区是对全球气候变化响应最为敏感的地区之一,也是水文变化剧烈和生态环境脆弱的地区。该地区包括了古丝绸之路的主体,在东西方交流和丝路文明兴衰历史中发挥了关键的作用。科学评估全球增温背景下亚洲中部干旱区人类社会可持续发展面临的风险,是广受关注的重大科学问题。东西方交流和丝路文明发展历史及其与气候环境变化关系的研究,可为认识该地区不同时间尺度人地关系演变的规律提供科学依据。通过总结东西方交流与丝路文明兴衰历史、亚洲中部干旱区全新世气候变化过程、多时间尺度气候一水文变化机制以及人与环境相互作用的过程与规律等领域的研究进展,提出目前亚洲中部干旱区全新世气候环境变化时空格局和丝路文明演化的过程,以及人与环境相互作用机制的研究存在明显不足。破解亚洲中部干旱区气候变化和文化演化研究区域不均衡问题,加强地学与考古学等多学科交叉研究,是推进气候变化与丝路文明变迁研究的有效途径。这对理解该地区人地关系演化规律、应对气候变化带来的挑战、服务国家“一带一路”倡议具有重要的科学价值和现实意义。 展开更多
关键词 亚洲中部干旱区 丝绸之路 气候环境变化 文明演化 人地关系
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自然地理学学科体系与发展战略要点 被引量:28
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作者 陈发虎 吴绍洪 +2 位作者 刘鸿雁 杨晓燕 刘建宝 《地理学报》 EI CSSCI CSCD 北大核心 2021年第9期2074-2082,共9页
自然地理学是地理科学的一门基础学科,同时也是生态学、环境科学等相关学科的科学基础。自然地理学重点研究地球表层自然环境的空间特征、演变过程及其地域分异规律,以及过去人—环境相互作用的发展过程。在社会经济和科学技术快速发展... 自然地理学是地理科学的一门基础学科,同时也是生态学、环境科学等相关学科的科学基础。自然地理学重点研究地球表层自然环境的空间特征、演变过程及其地域分异规律,以及过去人—环境相互作用的发展过程。在社会经济和科学技术快速发展的新时期,自然地理学与综合地理学、人文地理学、信息地理学的联系更加密切和广泛。本文结合《中国学科及前沿领域发展战略研究(2021—2035)》地理科学的学科规划,分析自然地理学学科的形成过程,阐述综合自然地理学、部门自然地理学、人类生存环境学的分支学科体系,提出自然地理学及其分支学科的学科发展战略布局、优先领域发展目标和重点方向。 展开更多
关键词 自然地理学 学科体系 发展战略
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1949年以前青藏高原探险和科学考察活动概况 被引量:5
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作者 陈发虎 王亚军 +1 位作者 丁林 姚檀栋 《地理学报》 EI CSSCI CSCD 北大核心 2022年第7期1565-1585,共21页
本文收集整理了1949年以前对青藏高原区域的主要探险和考察活动。青藏高原的探险和考察主要可划分为4个阶段:(1)古代主要是与国内外宗教活动相关的附带零星记录;(2)晚清时期主要是西方人以科学名义的初步科学考察;(3) 1912—1949年中外... 本文收集整理了1949年以前对青藏高原区域的主要探险和考察活动。青藏高原的探险和考察主要可划分为4个阶段:(1)古代主要是与国内外宗教活动相关的附带零星记录;(2)晚清时期主要是西方人以科学名义的初步科学考察;(3) 1912—1949年中外联合科学考察;(4) 1912—1949年中国学者主导的较系统科学考察。清代以前对青藏高原的考察,以地理现象描述、资料收集、单学科考察和研究为主,1912—1949年科学考察已过渡到采用简易科学仪器进行地理要素的测量、对某一专题(如植物)的局部区域有了比较深入的研究。1912—1949年中国学者从配合西方科学家开展联合科学考察发展到政府组织国内学者对青藏高原地理、地貌、地质和气象气候、植物等的考察和研究,中国学者的一些成果也开始走向国际,扩大了国内外对青藏高原的认识。 展开更多
关键词 青藏高原 探险考察 古代 清代 1912-1949年 1949年以前
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四套全球网格降水数据集在伊朗的适用性评估 被引量:1
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作者 马帅 李晨曦 +3 位作者 刘言 陈建徽 陈发虎 黄伟 《地理研究》 CSSCI CSCD 北大核心 2022年第11期3021-3035,共15页
伊朗由于其独特的地理位置和脆弱的生态环境一直以来都是气候变化研究的热点区域,降水作为伊朗水资源的重要来源对生态环境和社会经济发展尤为重要,因此评估降水数据集的适用性是进行科学研究的基础。本文利用伊朗1988—2017年103个观... 伊朗由于其独特的地理位置和脆弱的生态环境一直以来都是气候变化研究的热点区域,降水作为伊朗水资源的重要来源对生态环境和社会经济发展尤为重要,因此评估降水数据集的适用性是进行科学研究的基础。本文利用伊朗1988—2017年103个观测站的年降水数据(OBS),以平均偏差(Mean Error,ME)、均方根误差(Root Mean Square Error,RMSE)、相关系数(correlation coefficient,R)对Global Precipitation Climatology Centre(GPCC)V2020、Climatic Research Unit(CRU)TS 4.05、Terrestrial Air Temperature and Precipitation:Monthly and Annual Time Series(UDEL)V5.01和NOAA’s Precipitation Reconstruction over Land(PREC)四套全球网格降水数据集在伊朗的适用性进行评估,并进一步分析了地形对不同数据集精度的影响。研究结果显示:(1)GPCC降水数据偏差最小,与观测数据相关性最高,最适合伊朗现代气候变化研究。(2)GPCC、CRU、和UDEL均能反映伊朗降水的基本特征,但普遍会低估降水高值,PREC数据不能准确反映伊朗降水的空间分布模态,因此使用PREC数据分析伊朗降水特征时应当谨慎。(3)海拔和坡度对ME、RMSE以及R有一定影响,坡向对数据集精度影响不大。以上结论可为四套数据的订正及其在伊朗地区气候变化研究中的应用提供科学依据。 展开更多
关键词 伊朗 降水数据集评估 精度 海拔 坡度
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Tree ring based streamflow reconstruction for the Upper Yellow River over the past 1234 years 被引量:39
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作者 GOU XiaoHua DENG Yang +5 位作者 chen fahu YANG MeiXue FANG KeYan GAO LinLin YANG Tao ZHANG Fen 《Chinese Science Bulletin》 SCIE EI CAS 2010年第36期4179-4186,共8页
We established a Juniperus przewalski tree ring width chronology, based on tree ring cores collected from the A’nyêmaqên Mountains. Statistical analysis showed that the chronology was highly correlated with... We established a Juniperus przewalski tree ring width chronology, based on tree ring cores collected from the A’nyêmaqên Mountains. Statistical analysis showed that the chronology was highly correlated with instrumental streamflow records from previous August to current July from the Tangnaihai Station in the upper reaches of the Yellow River, with a correlation coefficient of 0.656. Streamflow for the upper reaches of the Yellow River was reconstructed for the past 1234 years. Low flow periods for the 11-year averaged streamflow reconstruction were definite as lower than mean plus 1 standard deviation, and high flow periods were higher than mean minus 1 standard deviation. Over the past 1234 years, high flows occurred 18 times, and low flows occurred 12 times. The main low flow periods were identified as AD 1140–1156, AD 1295–1309, AD 1473–1500, and AD 1820–1847, and the main high flow periods were identified as AD 846–873, and AD 1375–1400. Extremely low streamflow over the reconstruction period was seen during the late 15th century, coinciding with a widespread drought phenomenon, which took place in the northeastern Tibetan Plateau over the same period. Reconstructed streamflow shows significant low-frequency variability, which is in line with drought variability of neighboring regions, as inferred from tree rings and other proxies. Multi-taper spectral analysis suggests the existence of significant periods of 2–5, 22, 35–38, 55–62, and 114–227 years, particularly significant for cyclic variations of years 159 and 36. 展开更多
关键词 黄河上游 径流量 树木年轮 干旱现象 阿尼玛卿山 低流量 年轮宽度 普氏原羚
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Abrupt Holocene changes of the Asian monsoon at millen-nial-and centennial-scales: Evidence from lake sediment document in Minqin Basin, NW China 被引量:61
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作者 chen fahu ZHU Yan +3 位作者 LI Jijun SHI Qi JIN Liya B.Wunemann 《Chinese Science Bulletin》 SCIE EI CAS 2001年第23期1942-1947,共6页
Considerable research is now focusing on abrupt Holocene changes at millennial- and centennial-scales all over the world. This study shows that the changes in theHolocene summer monsoon can be divided into two main pe... Considerable research is now focusing on abrupt Holocene changes at millennial- and centennial-scales all over the world. This study shows that the changes in theHolocene summer monsoon can be divided into two main periods, based on climatic proxy records of lake sediments from the Sanjiaocheng section located at the NW boundary of the summer monsoon, Gansu Province. The early and middle Holocene was humid with stronger summer monsoon, while the late Holocene is dry with weak summer monsoon. Detailed results also show a series of millennial- and centennial-scale changes in the intensity of the summer monsoon, with a periodicity of 1600 years during the whole Holocene, and with a periodicity of 800 years during the early Holocene. Ten dry events during the Holocene are associated with the weakening of the summer monsoon. These rapid climatic changes may be representative of a global climatic change pattern during the Holocene. 展开更多
关键词 HOLOCENE lake DOCUMENT rapid changes.
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Humid Medieval Warm Period recorded by magnetic characteristics of sediments from Gonghai Lake, Shanxi, North China 被引量:29
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作者 LIU JianBao chen fahu +4 位作者 chen JianHui XIA DunSheng XU QingHai WANG ZongLi LI YueCong 《Chinese Science Bulletin》 SCIE EI CAS 2011年第23期2464-2474,共11页
Variations in monsoon strength, moisture or precipitation in eastern China during the MWP reflected by different climatic records have shown apparent discrepancies. Here, detailed environmental magnetic investigations... Variations in monsoon strength, moisture or precipitation in eastern China during the MWP reflected by different climatic records have shown apparent discrepancies. Here, detailed environmental magnetic investigations and mineralogical analyses were conducted on lacustrine sediments of Core GH09B1 (2.8 m long) from Gonghai Lake, Shanxi, North China, concerning the monsoon history during the MWP. The results demonstrate that the main magnetic mineral is magnetite. The sediments with relatively high magnetic mineral concentrations were characterized by relatively fine magnetic grain sizes, which were formed in a period of relatively strong pedogenesis and high precipitation. In contrast, the sediments with low magnetic mineral concentrations reflected an opposite process. The variations of magnetic parameters in Gonghai Lake sediments were mainly controlled by the degree of pedogenesis in the lake drainage basin, which further indicated the strength of the Asian summer monsoon. The variations in the and S 300 parameters of the core clearly reveal the Asian summer monsoon history over the last 1200 years in the study area, suggesting generally abundant precipitation and a strong summer monsoon during the Medieval Warm Period (MWP, AD 910–1220), which is supported by pollen evidence. Furthermore, this 3–6-year resolution environmental magnetic record indicates a dry event around AD 980–1050, interrupting the generally humid MWP. The summer monsoon evolution over the last millennium recorded by magnetic parameters in sediments from Gonghai Lake correlates well with historical documentation (North China) and speleothem oxygen isotopes (Wanxiang Cave), as well as precipitation modeling results (extratropical East Asia), which all indicate a generally humid MWP within which centennial-scale moisture variability existed. It is thus demonstrated that environmental magnetic parameters could be used as an effective proxy for monsoon climate variations in high-resolution lacustrine sediments. 展开更多
关键词 湖泊沉积物 中世纪暖期 磁性矿物 中国北方 潮湿 特征记录 山西 季风强度
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Exploring the history of cultural exchange in prehistoric Eurasia from the perspectives of crop diffusion and consumption 被引量:34
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作者 DONG GuangHui YANG YiShi +2 位作者 HAN JianYe WANG Hui chen fahu 《Science China Earth Sciences》 SCIE EI CAS CSCD 2017年第6期1110-1123,共14页
The history of cultural exchange in prehistoric Eurasia(CEPE) has been widely investigated. Based on archaeological evidence, this process is thought to date back to at least the early Bronze Age, although details abo... The history of cultural exchange in prehistoric Eurasia(CEPE) has been widely investigated. Based on archaeological evidence, this process is thought to date back to at least the early Bronze Age, although details about timings and routes remain unclear. It is likely that CEPE promoted the spread and exchange of crops that originated in different parts of Eurasia; since these remains can be definitely identified and directly dated, they provide ideal research materials to explore the history of CEPE. In this paper, we review the available archaeobotanical evidence and direct radiocarbon dates for crop remains, alongside carbon isotopic data from human bones unearthed from prehistoric sites in Eurasia, in order to investigate the history of the spread of millet crops, and wheat and barley, that were first domesticated in the eastern and western parts of Eurasia during prehistoric times.In combination with other archaeological evidences, we discuss the history of CEPE. Our results suggest that wheat and barley were domesticated in western Asia around 10500 a BP, spread into Europe and western Central Asia before 8000 a BP, and reaching eastern Central Asia and northwestern China between 4500 and 4000 a BP. Data show that both broomcorn and foxtail millet were domesticated in eastern Asia before 7700 a BP, spread into eastern Central Asia between 4500 and 4000 a BP, and into western Asia and Europe prior to 3500 a BP. Wheat, barley, and millet crops were first utilized together in eastern Kazakhstan within Central Asia around 4400 a BP, the region where earliest CEPE is likely to have taken place. These crops were mixedly used mainly in eastern central Asia and northwest China between 4500 and 3500 a BP, and then across the Eurasia before 2200 a BP. The results of this study suggest that transcontinental CEPE might have been initiated during the fifth millennium, before intensifying during the Bronze Age to lay the foundations for the creation of the ancient Silk Road during the Han Dynasty(between 202 BC and 220AD). 展开更多
关键词 NEOLITHIC Bronze Age EURASIA Crop spread Food globalization Transcontinental cultural exchange
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Interannual precipitation variations in the mid-latitude Asia and their association with large-scale atmospheric circulation 被引量:25
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作者 HUANG Wei chen fahu +2 位作者 FENG Song chen JianHui ZHANG XiaoJian 《Chinese Science Bulletin》 SCIE EI CAS 2013年第32期3962-3968,共7页
This study analyzed the spatial differences of the precipitation variations in the mid-latitude Asia and their possible physical mechanisms during 1960–2009.The annual precipitation showed an opposite variations betw... This study analyzed the spatial differences of the precipitation variations in the mid-latitude Asia and their possible physical mechanisms during 1960–2009.The annual precipitation showed an opposite variations between the westerlies-dominated arid Central Asia(ACA)and monsoon-dominated North China(NC)during the study period.Given the different contributions of seasonal precipitation to annual total precipitation in ACA and NC,the atmospheric circulation anomalies during the major precipitation seasons(winter in ACA/summer in NC)were analyzed.In winter,negative North Atlantic Oscillation may cause negative height anomalies over the north side and positive anomalies over the south side of the ACA.Together,the enhanced pressure gradient and anomalous westerly wind brings more water vapor to ACA,and leaves less precipitation in NC.In summer,the low-pressure anomalies in Northeast China,along with a weaker summer monsoon and negative height anomalies in Eastern Europe together contribute to reduced(excessive)summer precipitation in NC(ACA).The interactions between ENSO and NAO may result in the opposite precipitation variations between ACA and NC.A significant 2–3-year cycle is identified in ACA,which is linked to the variations of westerly circulation in the middle troposphere. 展开更多
关键词 大气环流异常 降水变化 中纬度地区 大尺度 关联 北卡罗来纳州 高度距平 北大西洋涛动
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Spatiotemporal precipitation variations in the arid Central Asia in the context of global warming 被引量:69
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作者 chen fahu HUANG Wei +2 位作者 JIN LiYa chen JianHui WANG JinSong 《Science China Earth Sciences》 SCIE EI CAS 2011年第12期1812-1821,共10页
This study analyzed the temporal precipitation variations in the arid Central Asia (ACA) and their regional differences during 1930-2009 using monthly gridded precipitation from the Climatic Research Unit (CRU). O... This study analyzed the temporal precipitation variations in the arid Central Asia (ACA) and their regional differences during 1930-2009 using monthly gridded precipitation from the Climatic Research Unit (CRU). Our results showed that the annual precipitation in this westerly circulation dominated arid region is generally increasing during the past 80 years, with an apparent increasing trend (0.7 mm/10 a) in winter. The precipitation variations in ACA also differ regionally, which can be divided into five distinct subregions (Ⅰ West Kazakhstan region, Ⅱ East Kazakhstan region, ⅢCentral Asia Plains region, Ⅳ Kyrgyzstan region, and V Iran Plateau region). The annual precipitation falls fairly even on all seasons in the two northern subregions (regions Ⅰ and Ⅱ, approximately north of 45°N), whereas the annual precipitation is falling mainly on winter and spring (accounting for up to 80% of the annual total precipitation) in the three southern subregions. The annual precipitation is increasing on all subregions except the southwestern ACA (subregion Ⅴ) during the past 80 years. A significant increase in precipitation appeared in subregions Ⅰ and Ⅲ. The long-term trends in annual precipitation in all subregions are determined mainly by trends in winter precipitation. Additionally, the precipitation in ACA has significant interannual variations. The 2-3-year cycle is identified in all subregions, while the 5-6-year cycle is also found in the three southern subregions. Besides the inter-annual variations, there were 3-4 episodic precipitation variations in all subregions, with the latest episodic change that started in the mid- to late 1970s. The precipitations in most of the study regions are fast increasing since the late 1970s. Overall, the responses of ACA precipitation to global warming are complicated. The variations of westerly circulation are likely the major factors that influence the precipitation variations in the study region. 展开更多
关键词 arid Central Asia annual and seasonal precipitation changing tendency regional difference
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Pollen-inferred vegetation and environmental changes since 16.7 ka BP at Balikun Lake, Xinjiang 被引量:23
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作者 TAO Shichen AN chenBang +6 位作者 chen fahu TANG LingYu WANG ZongLi LU YanBin LI ZhiFei ZHENG TongMing ZHAO JiaJu 《Chinese Science Bulletin》 SCIE EI CAS 2010年第22期2449-2457,共9页
A high-resolution fossil pollen record from the sedimentary cores of Balikun Lake, northwestern China, combined with modern surface pollen data, is used to reconstruct the history of vegetation and climatic change sin... A high-resolution fossil pollen record from the sedimentary cores of Balikun Lake, northwestern China, combined with modern surface pollen data, is used to reconstruct the history of vegetation and climatic change since 16.7 cal. ka BP. Fossil pollen assem-blages and lithology indicate that the study area was dominated by desert. The desert had extremely arid climate and lower effec-tive moisture during 16.7–7.9 cal. ka BP, especially from 16.7 to 8.9 cal. ka BP when the lake maybe dried up. During 8.9–7.9 cal. ka BP, the environment gradually recovered in this area. It was then followed by the optimum period from 7.9 to 4.3 cal. Ka BP, when the effective moisture obviously increased. It was characterized by the typical desert-steppe/steppe vegetation and was ac-companied with several patch-birch woodlands around the lake. After that, a short but extremely arid climatic event occurred during 4.3–3.8 cal. ka BP, and the vegetation quickly changed from desert-steppe/steppe to desert. It was a relatively optimum period from 3.8 to 0.53 cal. ka BP showing typical desert-steppe/meadow-steppe landscape. Since 0.53 cal. ka BP, the climate has shown signs of deteriorating again. Furthermore, regional comparison shows that the characteristics of climatic and environmental evolution in this area were clearly different from East Asia monsoonal area during the last 16.7 cal. ka BP. It was characterized by the arid climate during the late-glacial and early Holocene, and relatively wet during the mid-late Holocene. 展开更多
关键词 环境变化 巴里坤湖 花粉记录 BP 植被 中晚全新世 新疆 气候变化
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A 1000-year chironomid-based salinity reconstruction from varved sediments of Sugan Lake,Qaidam Basin,arid Northwest China,and its palaeoclimatic significance 被引量:23
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作者 chen JianHui chen fahu +3 位作者 ZHANG EnLou BROOKS Stephen J ZHOU AiFeng ZHANG JiaWu 《Chinese Science Bulletin》 SCIE EI CAS 2009年第20期3749-3759,共11页
A 1000-year high-resolution(~10 years) chironomid record from varved sediments of Sugan Lake,Qaidam Basin on the northern Tibetan Plateau,is presented.The chironomid assemblages are mainly composed of the relatively ... A 1000-year high-resolution(~10 years) chironomid record from varved sediments of Sugan Lake,Qaidam Basin on the northern Tibetan Plateau,is presented.The chironomid assemblages are mainly composed of the relatively high-saline-water taxa Psectrocladius barbimanus-type and Orthocladius/Cricotopus,and the relatively low-saline-water taxa Procladius and Psectrocladius sordidellus-type.Variations in the chironomid fauna and inferred salinities suggest that over the last millennium,the Sugan Lake catchment has alternated between contrasting climatic conditions,having a dry climate during the period 990―1550 AD,a relatively humid climate during the Little Ice Age(LIA)(1550―1840 AD),and a dry climate again from 1840 AD onwards.At the decadal to centennial scale,a wet event around 1200―1230 AD,interrupting the generally arid period(990―1550 AD),and a dry event around 1590―1700 AD,punctuating the generally humid period(1550―1840 AD),are clearly documented.Trends in the chironomid-based salinity time series indicate a highly unstable climate during the LIA when salinity fluctuations were of greater magnitude and higher frequency.The effective moisture evolution in the Sugan Lake catchment during the last millennium reconstructed by chironomid analysis is in broad agreement with previous palaeo-moisture data derived from other sites in arid Northwest China(ANC).The LIA,characterized by generally humid conditions over the west-erly-dominated ANC was distinctly different from that in monsoonal China,implying an "out-of-phase" relationship between moisture evolution in these two regions during the past 1000 years. 展开更多
关键词 西北干旱地区 柴达木盆地 古气候意义 沉积物 中国 盐度 纹层
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A 457-year reconstruction of precipitation in the southeastern Qinghai-Tibet Plateau,China using tree-ring records 被引量:17
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作者 GOU XiaoHua YANG Tao +3 位作者 GAO LinLin DENG Yang YANG MeiXue chen fahu 《Chinese Science Bulletin》 SCIE EI CAS 2013年第10期1107-1114,共8页
This paper presents a 457-year reconstruction of precipitation in the southeastern Qinghai-Tibet Plateau using tree-ring records.Tree-ring samples were collected from the Hengduan Mountains in the southeastern part of... This paper presents a 457-year reconstruction of precipitation in the southeastern Qinghai-Tibet Plateau using tree-ring records.Tree-ring samples were collected from the Hengduan Mountains in the southeastern part of the Qinghai-Tibet Plateau,China.A nearly 500-year chronology was developed using tree-ring width records.Correlation analysis shows moisture is the main factor limiting tree growth in this region.Ring-widths were significantly positively correlated with the Palmer Drought Severity Index(PDSI) and precipitation in many months.The highest correlation coefficient was found between the annual growth of trees and precipitation from the previous September to the current June(0.738).Based on this relationship,we reconstructed the precipitation history from 1509 to 2006.The reconstruction explains 54.4%(Radj2=53.5%,N=49,F=56.12) of the actual precipitation variation during the calibration period(1958-2006).During the reliable period of the reconstruction(1549-2006),some low-frequency climate signals are included,indicating this region has been getting wetter in the last 20 years.The reconstruction documents six apparently dry and five pluvial periods and the 17th century dry period lasted longer than any other.When compared with other recent studies,this study and these earlier reconstructions show a similar trend in the variation of drought and pluvial.Further spatial correlation analysis confirms that the reconstructed precipitation adequately represents the rainfall history of the entire Hengduan Mountain area.The Multi-taper method,a type of spectral analysis,reveals that precipitation in this area had significant(P<0.01) spectral peaks at 3-5 a,60 a and 79-85 a. 展开更多
关键词 青藏高原东南部 降水重建 树木年轮 中国 降水量变化 树轮宽度 干旱指数 相关性分析
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Climatic changes documented by stable isotopes of sedimentary carbonate in Lake Sugan,northeastern Tibetan Plateau of China,since 2 kaBP 被引量:21
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作者 QIANG Mingrui chen fahu +2 位作者 ZHANG Jiawu GAO Shang-yu ZHOU Aifeng 《Chinese Science Bulletin》 SCIE EI CAS 2005年第17期1930-1939,共10页
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 an... 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. 展开更多
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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