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Pollen assemblage characteristics of lakes in the monsoon fringe area of China

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Chinese Science Bulletin 2008年第4期53卷 3354-3363页

作者： TIAN Fang1,2,xu qinghai1,2,3,LI YueCong1,2,CAO XianYong1,2,WANG xueLi1,2 & ZHANG LiYan1,2 1 College of Resources and Environmental Sciences,Hebei Normal University,Shijiazhuang 050016,China 2 Hebei Key Laboratory of Environmental Change and Ecological Construction,Shijiazhuang 050016,China 3 Key Laboratory of Western China’s Environmental System(Ministry of Education),Lanzhou University,Lanzhou 730000,China College of Resources and Environmental Sciences Hebei Normal University Shijiazhuang 050016 China Hebei Key Laboratory of Environmental Change and Ecological Construction Shijiazhuang 050016 China Key Laboratory of Western China's Environmental System (Ministry of Education) Lanzhou University Lanzhou 730000 China

This paper presents the pollen assemblages from 108 surface sediment samples from 4 lakes(the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao) in the monsoon fringe area of *** herb pollen taxa Artemisia,Chenopodiaceae,Poaceae and Compositae are the major components of pollen assemblages of the 4 lakes and Pinus,Betula,Quercus,Ulmus,Populus,Ostryopsis and Elaeagnaceae are frequently presented,which reflect regional and local vegetation *** mean similarity coefficients for samples from the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao are 0.66 ± 0.17,0.71 ± 0.11,0.73 ± 0.12 and 0.67 ± 0.12 respectively,so pollen assemblages are relatively consistent in each lake,which shows that focusing and mixing effects have occurred before and after pollen ***,pollen assemblages do differ between sampling sites in each *** largest difference is seen in the Lake Daihai,followed by the Lake Duikounao,Lake Hulunnao and Lake Hongjiannao(The mean Euclidean distance is 20.09 ± 11.11,11.22 ± 3.64,10.67 ± 4.03 and 8.44 ± 4.51 respectively).These differences are possibly caused by the differences of focusing and mixing effects,pollen source areas,drainage areas and regional vegetation *** Lake Daihai and Lake Hongjiannao have water deeper than 5 m and strong re-suspension,focusing and mixing effects occur in the lakeshore and shallow water areas,where pollen concentrations are lower than in deeper lake *** the Lake Hulunnao and Lake Duikounao,with depths less than 5 m,re-suspension and mixing effects are obvious across the whole lake area,so pollen assemblages and pollen concentra-tions are more consistent among sampling sites in each *** between the lake samples and samples from the inflowing river reveals that wind is primary pollen transportation force in the Lake Hongjiannao,where the consistency of pollen assemblage is conspicuous,while there is greater variation in lakes where pollen input is

关键词：湖泊花粉相似系数欧几里得季风

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A process-oriented approach for identifying potential landslides considering time-dependent behaviors beyond geomorphological features

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 961-978页

作者： Xiang Sun Guoqing Chen Xing Yang Zhengxuan xu Jingxi Yang Zhiheng Lin Yunpeng Liu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China China Railway Eryuan Engineering Group Co.Ltd. Chengdu610031China Power China Chengdu Engineering Co.Ltd. Chengdu610072China

Geomorphological features are commonly used to identify potential ***,overemphasis on these features could lead to *** research proposes a process-oriented approach for potential landslide identification that considers time-dependent *** method integrates comprehensive remote sensing and geological analysis to qualitatively assess slope stability,and employs numerical analysis to quantitatively calculate aging ***,a time-dependent stability calculation method for anticlinal slopes is developed and implemented in discrete element software,incorporating time-dependent mechanical and strength reduction *** considering the time-dependent evolution of slopes,this method highlights the importance of both geomorphological features and time-dependent behaviors in landslide *** method has been applied to the Jiarishan slope(JRS)on the qinghai-Tibet Plateau as a case *** results show that the JRS,despite having landslide geomorphology,is a stable slope,highlighting the risk of misjudgment when relying solely on geomorphological *** work provides insights into the geomorphological characterization and evolution history of the JRS and offers valuable guidance for studying slopes with similar landslide ***,the process-oriented method incorporating timedependent evolution provides a means to evaluate potential landslides,reducing misjudgment due to excessive reliance on geomorphological features.

关键词： Geomorphological features Evolution history Time-dependent stability calculation Landslides identification qinghai-Tibet Plateau

Pollen assemblages from different agricultural units and their spatial distribution in Anyang area

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Chinese Science Bulletin 2010年第6期55卷 544-554页

作者： WANG xueLi1,2,LI YueCong1,2,xu qinghai1,2,CAO XianYong1,2,ZHANG LiYan1,2 & TIAN Fang1,2 1 College of Resource and Environmental Sciences,Hebei Normal University,Shijiazhuang 050016,China 2 Hebei Key Laboratory of Environmental Change and Ecological Construction,Shijiazhuang 050016,China College of Resource and Environmental Sciences Hebei Normal University Shijiazhuang China Hebei Key Laboratory of Environmental Change and Ecological Construction Shijiazhuang China

Pollen analysis is one of the best and possible approaches for the quantitative reconstruction of paleobotany and paleoclimate,and discrimination of human *** this paper,we reveal the characteristics of pollen assemblages in different agricultural units and their spatial distribution of major pollen taxa in the Anyang area where the human influences are serious,so as to get more information about climate change and human activities from pollen *** pollen assemblages of total 122 surface soil samples from different agricultural units (farm lands,vegetable plots,wastelands,cape-lands,woodlands,etc.) indicate that herbaceous pollen dominates the pollen assemblages with an average of 73%,mainly from Poaceae,Artemisia,Chenopodiaceae and Cruciferae;arboreal pollen percentages reach 18%,mainly from Pinus and Ulmus;shrub pollen and fern spores have very low *** general,pollen assemblages are consistent with vegetation composition,though some differences also exist in different agricultural *** farmlands and vegetable lands,Poaceae pollen has the highest percentages (averaging 27%) compared to other agricultural units with dominant corn or wheat pollen,while in wastelands and woodlands,arboreal and Artemisia pollen percentages have higher values (averaging 20% and 19% respectively).Cruciferae has the highest pollen percentages (70%) in *** pollen assemblages and PCoA can generally identify the vegetable plots,farmlands,woodlands,wastelands,and *** and Artemisia pollens mainly appear in the western part of Anyang,which is consistent with the parent plants;Poaceae pollen mainly exist in the eastern part with more farmlands;Chenopodiaceae pollen mainly appear in the urban areas and near major roads where human influences are stronger,Cruciferae pollen can mainly be found in the urban area and in the northwest part of Anyang where more vegetables are planted.

关键词：安阳地区空间分布花粉组合单位农业

中国东部北黄海盆地东部坳陷岩浆活动特征及其与区域构造的耦合关系

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地球科学（中国地质大学学报） 2017年第4期42卷 587-600页

作者：王任石万忠张先平唐大卿陈昊然徐清海徐壮中国地质大学资源学院湖北武汉430074 中国地质大学构造与油气资源教育部重点实验室湖北武汉430074 中石化重庆涪陵页岩气勘探开发有限公司重庆408000

如何深入了解中国东部北黄海盆地东部坳陷岩浆活动特征是目前研究的前沿之一.为探讨早白垩世异常剧烈岩浆活动的区域构造成因并揭示中国东部的构造动力学机制,利用井-震及岩浆岩测试资料,对北黄海盆地岩浆活动特征及其与区域构造的耦合... 详细信息

如何深入了解中国东部北黄海盆地东部坳陷岩浆活动特征是目前研究的前沿之一.为探讨早白垩世异常剧烈岩浆活动的区域构造成因并揭示中国东部的构造动力学机制,利用井-震及岩浆岩测试资料,对北黄海盆地岩浆活动特征及其与区域构造的耦合关系进行研究.在空间上刻画了岩浆的侵入相、喷出相的地震反射特征及沿深大断裂展布的平面分布特征;在时间上划分出了包括早白垩世108~115Ma、134~145Ma在内的4期岩浆活动.结合区域地质分析认为早白垩世早期,伊泽奈琦板块沿北北西斜向俯冲于欧亚板块之下,太平洋板块向南西方向俯冲,板块剪切作用导致郯庐断裂带左旋走滑,使得盆地处于左旋伸展环境中,内部形成派生的北西向右旋、近南北向左旋的次级共轭断裂系并控制岩浆上侵底辟活动.经过综合分析,厘清了盆地岩浆活动及断裂演化过程与区域板块运动之间的耦合关系.

关键词：中国东部北黄海盆地岩浆活动构造学耦合关系.

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北黄海盆地下白垩统层序构成特点及控制因素

石油学报 2015年第12期36卷 1531-1542页

作者：王任石万忠肖丹夏飞夏治旻徐清海中国地质大学资源学院湖北武汉430074 中国地质大学构造与油气资源教育部重点实验室湖北武汉430074

北黄海盆地下白垩统属于湖相沉积。通过钻井及高精度三维地震资料可以清楚地在下白垩统下部地层中识别出层序的低位体系域、水进体系域、高位体系域、初次水进面以及最大洪泛面的特征。低位体系域包括下切谷、低位进积楔以及低位扇;高... 详细信息

北黄海盆地下白垩统属于湖相沉积。通过钻井及高精度三维地震资料可以清楚地在下白垩统下部地层中识别出层序的低位体系域、水进体系域、高位体系域、初次水进面以及最大洪泛面的特征。低位体系域包括下切谷、低位进积楔以及低位扇;高位体系域被层序顶界面及最大洪泛面所限定,并以发育有进积型准层序组为特征;水进体系域位于低位体系域与高位体系域中间,以退积型准层序组为主要特征。通过地质分析可以概括出层序发育的主要控制因素:1根据火成岩测试年龄及地震解释成果认为,晚侏罗世晚期—早白垩世早期岩浆活动造成地层抬升减薄,导致了构造坡折带的形成。2基于坡折带以上4口井的岩性资料发现,水进体系域和高位体系域沉积夹杂有红色泥岩。地震剖面显示层序顶界面超覆于底界面之上,层序分布范围明显小于其上覆和下伏层序的范围,同时在坡折带以下地区识别出了低位扇体和进积楔。以上证据表明该时期湖平面下降至坡折带以下地区且沉积中心发生迁移。3地震资料所显示的斜坡扇沉积,岩心资料所证实的砾石颗粒支撑和泥质填隙、泥砾的存在以及录井岩性所显示的高含砂量(60%~70%)均显示出早白垩世早期为持续大物源供给。因此,控制北黄海盆地下白垩统层序形成的3个控制因素可以概括为构造坡折带的形成、湖平面的下降以及大物源的供给。

关键词：层序构成控制因素构造坡折下白垩统北黄海盆地

东海陆架盆地西湖凹陷平湖组断层组合样式及其控砂机制

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石油与天然气地质 2020年第4期41卷 824-837页

作者：陈哲张昌民侯国伟冯文杰徐清海长江大学地球科学学院湖北武汉430100 中海石油(中国)有限公司上海分公司上海200335

东海陆架盆地西湖凹陷是中国沿海重要的含油气区,勘探实践中发现其内部断层及砂体分布规律复杂、勘探难度大,亟待解决砂体分布控制因素问题,深化砂体分布规律认识。运用岩心、测井及三维地震资料,采用古地貌和地震属性叠合精细砂体解释... 详细信息

东海陆架盆地西湖凹陷是中国沿海重要的含油气区,勘探实践中发现其内部断层及砂体分布规律复杂、勘探难度大,亟待解决砂体分布控制因素问题,深化砂体分布规律认识。运用岩心、测井及三维地震资料,采用古地貌和地震属性叠合精细砂体解释技术,对西湖凹陷平湖组同沉积断层分布及组合特征对砂体的控制作用开展了研究。根据同沉积断层发育规模的差异,划分出3个级别的断层,分别控制了凹陷格局、斜坡特征及砂体展布3个层次,分析了三级同沉积断层组合样式对砂体垂向沉积特征及平面展布方向的控制作用。研究表明,研究区发育6种断层控砂模式,分别为正向断阶阶梯型、正向断阶掀斜型、正向断阶叠覆型、墙角型、反向断阶型和正反向断阶复合型控砂模式。其中由正向断层构成的断层组合样式有利于砂体向凹陷中央搬运,扩大了储层在凹陷内的分布规模,而由反向断层构成的断层组合样式,其富砂作用显著、油气聚集条件优越。在6种断层控砂模式的指导下,有利于发现砂体垂向富集段及横向富集带,判断砂体展布方向及预测储层发育位置。

关键词：同沉积断层反向断层控砂机制砂体分布平湖组西湖凹陷东海陆架盆地

Present-day movement characteristics of the qinghai Nanshan fault and its surrounding area from GPS observation

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Geodesy and Geodynamics 2024年第2期15卷 133-141页

作者： Yang Liu Yuxuan Qiu Jialiang Liu Luyun Xiong Caijun xu Jianghui Geng Gang Zheng Tianchen Sheng School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Key Laboratory of Geospace Environment and Geodesy Ministry of EducationWuhan UniversityWuhan 430079China Key Laboratory of Geophysical Geodesy Ministry of Natural ResourcesWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China School of Earth and Environment University of LeedsLeeds LS29JTUK qinghai Basic Surveying and Mapping Institute Xining 810101China

The qinghai Nanshan fault is a larger fault in the Northeastern Xizang *** previous studies,its movement characteristics are mainly investigated with geological and seismic observations,and the tectonic transformation role of the fault on its east is not yet *** study uses data fusion to obtain denser GPS observations near the qinghai Nanshan *** on tectonic characteristics,we establish a block model to investigate the fault slip rate,locking degree,and slip *** results show that the qinghai Nanshan fault slip rate is characterized by sinistral and convergent *** the sinistral and convergent rates display a decreasing trend from west to *** locking degree and slip deficit are higher in the western segment(with an average of about 0.74 and 1.1 mm/a)and lower in the eastern ***,we construct a strain rate field using GPS observations to analyze the regional strain *** results indicate that along the fault,the western segment shows a larger shear strain rate and negative dilation *** earthquake records show that the frequency of earthquakes is lower near the *** joint results suggest that the western segment may have a higher earthquake *** addition,the insignificant fault slip rate in the eastern segment may indicate that it does not participate in the tectonic transformation among the Riyueshan,Lajishan,and West Qinling faults.

关键词： The qinghai Nanshan fault Movement characteristics Block model Slip rate GPS

华北平原东北部小冰期干湿变化特征及其驱动机制

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第四纪研究 2022年第6期42卷 1586-1600页

作者：范保硕李月丛吕厚远许清海谢红丽张芸佘梓靖葛亚汶张振赵永杰河北师范大学地理科学学院河北石家庄050024 河北省环境演变与生态建设重点实验室河北石家庄050024 河北省环境变化遥感识别技术创新中心河北石家庄050024 中国科学院地质与地球物理研究所中国科学院新生代地质与环境重点实验室北京100029 中国地质调查局第四纪年代学与水文环境演变重点实验室河北石家庄050061

小冰期作为距今最近的一次冷期,是研究寒冷事件对人类社会和自然环境影响的重要参照期,其气候总体偏冷已达成共识,但干湿变化存在明显的时间和区域差异。华北平原作为东亚季风系统控制的核心区,对气候变化响应十分敏感,由于受到研究材... 详细信息

小冰期作为距今最近的一次冷期,是研究寒冷事件对人类社会和自然环境影响的重要参照期,其气候总体偏冷已达成共识,但干湿变化存在明显的时间和区域差异。华北平原作为东亚季风系统控制的核心区,对气候变化响应十分敏感,由于受到研究材料、技术方法等因素限制,致使华北平原小冰期次一级干湿变化过程研究较少,且缺乏高分辨率的定量研究。本研究在6个AMSC定年的基础上,通过对秦皇岛七里海湖泊深度为245~62 cm的钻孔沉积物92个样品的孢粉分析,利用加权平均偏最小二乘回归法(WA-PLS),高分辨率地定量重建了华北平原东北部1250~1610 A.D.的降水变化过程。结果显示:小冰期早期(1310~1450 A.D.)年降水量平均为565 mm,较中世纪温暖期降水减少约25 mm,气候变干,但程度较轻;小冰期中期(1450~1610 A.D.)降水量进一步降低,降至525 mm左右,最低可达410 mm,气候达到研究段最为干旱时期。分析认为,华北平原东北部地区小冰期冷干变化过程可能受太阳辐射量、火山活动和太平洋年代际振荡(PDO)的共同驱动。

关键词：华北平原东北部七里海小冰期降水定量重建孢粉分析

石家庄市空气花粉散布规律及与气候因子的关系

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生态学报 2014年第6期34卷 1575-1586页

作者：李英李月丛吕素青许清海河北师范大学资源与环境科学学院河北省环境演变与生态建设重点实验室石家庄050024

石家庄市2007—2009连续两年空气花粉分析表明:受植物花期影响,春季以木本植物花粉为主,夏、秋季以草本植物花粉为主,不同类型花粉通量存在一定年际差异。松属、杨属、胡桃属等当地花粉含量占花粉组合的80.0%以上,桦木属、栎属、虎榛子... 详细信息

石家庄市2007—2009连续两年空气花粉分析表明:受植物花期影响,春季以木本植物花粉为主,夏、秋季以草本植物花粉为主,不同类型花粉通量存在一定年际差异。松属、杨属、胡桃属等当地花粉含量占花粉组合的80.0%以上,桦木属、栎属、虎榛子属等区域花粉含量低于20.0%,显示空气花粉能较好地反映周围植被,但也受区域植被的影响。依据空气花粉通量变化规律,石家庄市主要空气花粉类型通量从高到低排在前5位的依次为:胡桃属、悬铃木属、蒿属、杨属、藜科,均为高致敏类型,花粉过敏症患者在其花期或通量较高时期应早作防范。空气花粉百分含量与气候因子之间的(CCA)分析结果显示,其主要受风速与水汽压影响;不同季节主要花粉类型通量与气候因子的相关分析表明:春季和秋季空气花粉通量主要受气温和水汽压的影响,夏季主要受相对湿度和水汽压的影响,冬季与气候因子相关较弱。

关键词：石家庄市空气花粉组合气候因子 CCA分析相关分析