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East Asian Winter Monsoon record from the environmental sensitive grain size component of QF Old Red Sand, Haitan Island, China

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Research in Cold and Arid Regions 2013年第2期5卷 220-229页

作者： fangen hu ZhiZhong Li Jianhui Jin Qian Zhao hui Zhang XianLi Wang Jing Xia College of Geographical Science Fujian Normal University Key Laboratory of humid Sub-tropical Eco-geographical Process of Ministry of Education State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Institute of Geography Fujian Normal University

The ＂Old Red Sand＂ is widely distributed along the coast of Fujian Province, China. Most studies have been carried out from as- pects of the origin, age and laterization of the ＂Old Red Sand＂, but this paper focused on reconstructing the history of the Asian Winter Monsoon change. On the basis of granulometric analysis of high-resohition samples, we have obtained environmental sen- sitive grain size component （ESGSC） from the Qingfeng （QF） profile by using the grain size-standard deviation method, which proves that the selected ESGSC is an important climate proxy. The mean grain size of this ESGSC could be used to reconstruct the East Asian Winter Monsoon （EAWM） intensity. As such, the history of the EAWM change since 44.0 ka reconstructed here reveals three main phases based on chronology dates of previous researches：（1） 44.0-25.5 ka B.P., the EAWM is relatively weak but increases gradually with fluctuations; （2） 25.5-15.5 ka B.P., relatively strong with high frequency fluctuations; （3） 15.5-7.1 ka B.P., with a weaker winter monsoon, but during 11-10 ka B.P. is remarkably enhanced. The EAWM recorded by mean grain size of the two neighboring sections have a better repeatability, so the millennial scales oscillation should be a reliable signal of the EAWM intensity. The climate recorded by ESGSC of the QF ＂Old Red Sand＂ compared to 6-80 of huhi Cave stalagmites and Greenland GISP2 ice cores shows a good consistency, especially in detail, the YD event and four Heinrich events are all recorded, but the signal of D-O cycles was relatively weak.

关键词： Old Red Sand sensitive grain size East Asian Winter Monsoon Heinrich event

Holocene aeolian stratigraphic sequences in the eastern portion of the desert belt(sand seas and sandy lands) in northern China and their palaeoenvironmental implications

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Science China Earth Sciences 2019年第8期62卷 1302-1315页

作者： Xiaoping YANG Peng LIANG Deguo ZHANG Hongwei LI Patrick RIOUAL Xulong WANG Bing XU Zhibang MA Qianqian LIU Xiaozong REN fangen hu Yuxin HE Gang RAO Ninghua CHEN Department of Geography School of Earth SciencesZhejiang UniversityHangzhou310027China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China University of Chinese Academy of Sciences Beijing100049China State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China Institute of Chinese Historical Geography Fudan UniversityShanghai200433China School of Geography Taiyuan Normal UniversityTaiyuan030619China College of Teachers’Education Yichun UniversityYichun336000China Department of Geology School of Earth SciencesZhejiang UniversityHangzhou310027China

This paper presents the environmental history and its responses to palaeoclimatic changes since the start of the Holocene in the eastern portion of the desert belt(sand seas and sandy lands) in northern China by comparing the aeolian sandpalaeosol sequences and their palaeoclimatic proxies. The optically stimulated luminescence(OSL) ages of the aeolian sandpalaeosol sedimentary sequences and a series of palaeoenvironmental proxies show that:(1) The large-scale dune landscape currently in the Kubuqi Sand Sea was formed during the Holocene in general;and the palaeosol was generally developed during the period of 4–2 ka, indicating conditions favorable for vegetation growth, soil development, and organic carbon accumulation due to increased precipitation or effective moisture and weakened aeolian activities;the large-scale expansion of dunes in the recent 2 ka is closely linked to human activities. The variable discharge of the Yellow River with diversions for irrigation may have resulted in a more consistent supply of aeolian particles for dune field expansion.(2) The dune landscape of the hunshandake Sandy Land was likely formed around 12 ka, and before this, the western part of the hunshandake Sandy Land would have been covered by a single large lake;it was obviously wetter than today in the sandy land during the period of 9.6–3 ka and the palaeosols were developed at the same time. But the aeolian activities have not been completely dormant in this long-lasting wetter epoch;because the Holocene wetter period was likely time-transgressive across the region.(3) The palaeosol of the hulunbuir Sandy Land began to develop as early as 14.5 ka, probably continuing until the last 2 ka. The palaeosol development of various dune fields in the eastern portion of the desert belt(sand seas and sandy lands) in northern China is spatially heterogeneous, and even the palaeosol development time in different locations within each sandy land is inconsistent. During the middle Holocen

关键词： Sand sea Sandy land,Environmental evolution,Kubuqi,hunshandake,hulunbuir

“金课”建设背景下“环境演变与全球变化”课程教学改革实践

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中国地质教育 2022年第3期31卷 87-92页

作者：黄伟刘茹胡凡根车彦军宜春学院地理科学系江西宜春336000

以全球变暖为标志的全球变化问题已成为当前国际社会关注度的焦点。我国越来越多的高校开设了“全球变化”课程,但传统教学模式难以取得良好效果。基于“认知—建构主义”学习理论,以“金课”建设为目标,本文从教学内容、教学方法、教... 详细信息

以全球变暖为标志的全球变化问题已成为当前国际社会关注度的焦点。我国越来越多的高校开设了“全球变化”课程,但传统教学模式难以取得良好效果。基于“认知—建构主义”学习理论,以“金课”建设为目标,本文从教学内容、教学方法、教学程序和教学评价等方面开展分析和探讨,并提出教学思考和建议。该教学模式不但有助于提高学生的学习积极性,培养其独立思考的思维习惯和积极健全的情感态度,而且有助于教师自身教学水平和课程思政引导能力的提升,从中获得教学动力和成就感。

关键词：金课全球变化地理科学教学改革

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福建晋江海岸带老红砂多期发育模式初步研究

第四纪研究 2012年第6期32卷 1207-1220页

作者：胡凡根李志忠靳建辉陈秀玲夏菁王贤立福建师范大学地理科学学院福州350007 湿润亚热带生态地理过程省部共建教育部重点实验室福州350007 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室西安710075 福建师范大学地理研究所福州350007

我国东南沿海广泛分布的老红砂是海岸环境演变的产物。通过对福建晋江海岸带科任(KR)老红砂剖面加密采样进行OSL测年和粒度分析,初步确定了老红砂发育期次及其形成时代。以OSL测年值为基础,在统一的时间标尺上综合对比全球海平面和东亚... 详细信息

我国东南沿海广泛分布的老红砂是海岸环境演变的产物。通过对福建晋江海岸带科任(KR)老红砂剖面加密采样进行OSL测年和粒度分析,初步确定了老红砂发育期次及其形成时代。以OSL测年值为基础,在统一的时间标尺上综合对比全球海平面和东亚季风变化序列,探讨了老红砂发育模式及其环境意义。研究表明:科任老红砂主要是晚更新世末次间冰期以来发育的,主要发生在约125～9ka期间,可以划分为6个沉积期,分别为125～115ka,105～97ka,84～74ka,61.5～52.0ka,39～29ka和15～9ka,期间可能存在至少5次明显的沉积间断。结合台湾海峡的水深变化特点分析,当海平面低于-70m时,由于研究区远离古海岸线,因而不可能有海岸风沙沉积;当海平面低于-15m高于-70m时,受到较强冬季风吹扬搬运海滩砂再沉积过程的影响,研究区可能有海岸风沙发育;当海平面高于-15m时,古今海岸线位置接近,在各种强度的冬季风作用下,研究区都会有海岸风沙广泛发育,并经历强烈的红化作用。即,科任老红砂主要发育于晚更新世末次间冰期以来气候暖湿的高海面和较高海面时期,而在末次冰期的低海面时期多次缺失海岸风沙沉积,尤其是末次盛冰期(LGM)的最低海面时期,现代海岸带所在区域老红砂发生沉积间断。

关键词：老红砂光释光多期沉积海平面变化东亚季风福建晋江

赣南红壤地区马尾松林和草地土壤呼吸变化研究

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海南师范大学学报（自然科学版） 2011年第1期24卷 101-107页

作者：胡凡根李志忠熊平生赵倩张辉湿润亚热带生态地理过程省部共建教育部重点实验室福建福州350007 福建师范大学地理科学学院福建福州350007 赣南师范学院江西赣州341000

采用碱液(NaOH)吸收法对赣南红壤地区马尾松和草地两种植被类型的土壤呼吸速率的变化及其影响因子进行了测定.结果表明:不同植被类型的土壤呼吸速率有显著差异(P<0.05),马尾松和草地土壤呼吸的变化与温度的变化趋势具有一定的相关性,观... 详细信息

采用碱液(NaOH)吸收法对赣南红壤地区马尾松和草地两种植被类型的土壤呼吸速率的变化及其影响因子进行了测定.结果表明:不同植被类型的土壤呼吸速率有显著差异(P<0.05),马尾松和草地土壤呼吸的变化与温度的变化趋势具有一定的相关性,观测期间,土壤呼吸速率5月最高,1月最低,且土壤呼吸总体速率草地大于马尾松林地,但1月和2月马尾松林地大于草地;马尾松土壤呼吸速率与温度具有较好的线性关系,而与草地则具有较好的指数相关关系,且都与地下5cm处土壤温度相关性最好;短暂或临时性的降雨对土壤呼吸具有速率显著争强的影响;不同植被类型对温度的敏感性(即Q10值)存在一定程度的差异,马尾松林地的Q10值小于草地的Q10值.

关键词：土壤呼吸红壤马尾松草地土壤温度 Q10值

福建北部天湖山全新世泥炭古气候记录的初步研究

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宁夏大学学报（自然科学版） 2012年第1期33卷 120-124页

作者：张辉李志忠姜修洋靳建辉胡凡根赵倩马鹏福建师范大学地理研究所福建福州350007 福建师范大学地理科学学院福建福州350007 福建亚热带资源与环境重点实验室福建福州350007 山西运城师范学院山西运城044000

通过对福建北部天湖山泥炭沉积记录的有机质含量和腐殖化度等多种环境代用指标的综合分析,在可靠14C测年技术的支持下,恢复了福建北部天湖山近10cal kyr BP以来的气候与环境演变过程.结果发现,泥炭有机含量和腐殖化度敏感地记录了研究... 详细信息

通过对福建北部天湖山泥炭沉积记录的有机质含量和腐殖化度等多种环境代用指标的综合分析,在可靠14C测年技术的支持下,恢复了福建北部天湖山近10cal kyr BP以来的气候与环境演变过程.结果发现,泥炭有机含量和腐殖化度敏感地记录了研究区古气候变化信息,其低值指示气候相对暖湿,高值指示气候相对冷干.约10～4cal kyr BP泥炭有机质含量和腐殖化度较高,指示气候暖湿,是该区域水热组合状况最好;4cal kyr BP以来泥炭有机质含量和腐殖化度较低,指示气候相对干冷.细分千年尺度的气候变化阶段有待于测年精度的进一步提高.

关键词：泥炭有机质腐殖化度古气候福建北部