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河北沧州东北部南大港湿地晩全新世环境演变特征

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第四纪研究 2024年第3期44卷 755-769页

作者：赵永杰由翰飞张振杨光李月丛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 河北师范大学汇华学院河北石家庄050091 河北地质大学地球科学学院河北石家庄050031 广东省地质局第一地质大队广东珠海519000

滨海湿地是全球变化背景下受到严重威胁的生态脆弱带和环境变化敏感区。揭示滨海湿地在长期气候变化和人类活动影响下的演变规律,有助于确定生态系统失衡的阈值,实现对滨海湿地的保护和可持续利用。本研究在8个AMS 14C测年数据基础上,... 详细信息

滨海湿地是全球变化背景下受到严重威胁的生态脆弱带和环境变化敏感区。揭示滨海湿地在长期气候变化和人类活动影响下的演变规律,有助于确定生态系统失衡的阈值,实现对滨海湿地的保护和可持续利用。本研究在8个AMS 14C测年数据基础上,基于孢粉、藻类、粒度、地球化学元素以及氧同位素等代用指标的变化,揭示了河北省沧州市东北部南大港湿地(剖面0~4 m)近4000年以来的环境演变过程及其驱动因素。结果表明:1)南大港湿地在3850~3570 cal.a B.P.期间,端元组分以EM3(海洋沉积)为主,沟鞭藻浓度较高,Cl元素含量和Sr/Ca值为研究段最高,Ti和K元素含量较低,说明沉积环境主要受到海洋影响,为开阔的浅海环境;3570~3450 cal.a B.P.期间,端元组分变为以EM1(河流沉积)为主,沟鞭藻浓度减少,Cl元素含量和Sr/Ca比值降低,Ti和K元素含量增加,陆源沉积物汇集明显,海洋影响减弱,此阶段应为潟湖环境;3450 cal.a B.P.以来,端元组分EM1(河流沉积)减少,EM2(风成或近源沉积)组分增加,沟鞭藻浓度明显减少,表明潟湖消亡,滨海湿地形成。2)南大港湿地岩芯钻孔孢粉组合特征显示3500 cal.a B.P.前后差异显著,3500 cal.a B.P.前孢粉组合以松属和栎属等木本植物为主,区域内木本植物盖度较大;而在3500 cal.a B.P.之后,孢粉组合中木本花粉含量明显减少,近源的草本花粉占据主导,包括藜科和禾本科这些典型的湿地草本植物大量增加,喜干旱环境的蒿属植物增加,指示森林植被占比下降,草地植被占比升高。3)约3500 cal.a B.P.之后木本花粉的减少及草本花粉的增加主要与3500 cal.a B.P.弱季风事件有关,该时期全球太阳辐射量降低,东亚夏季风减弱,气候向冷干化发展,使得渤海湾西部地区植被盖度下降,水土流失加剧,河流输沙能力增强并在海岸处大量沉积,相对海平面下降,南大港湿地形成。

关键词：晩全新世南大港湿地沉积环境花粉组合 3500 cal.a B.P.弱季风事件

泥河湾盆地上新世-更新世过渡时期野火与植被和气候变化

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第四纪研究 2024年第1期44卷 16-28页

作者：张振赵永杰刘超飞丁国强李月丛河北地质大学地球科学学院河北石家庄050031 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 河北师范大学汇华学院河北石家庄050091 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 兰州大学资源环境学院西部环境教育部重点实验室兰州730000

上新世-更新世过渡时期是地球气候由相对温暖的上新世向第四纪冰期-间冰期旋回模式转变的重要阶段,也是现代气候和生态系统形成过程中的关键时期。野火作为地球生态系统重要的扰动因子,直接影响着地球生态环境结构和功能的演变,对维持... 详细信息

上新世-更新世过渡时期是地球气候由相对温暖的上新世向第四纪冰期-间冰期旋回模式转变的重要阶段,也是现代气候和生态系统形成过程中的关键时期。野火作为地球生态系统重要的扰动因子,直接影响着地球生态环境结构和功能的演变,对维持地球生态系统平衡具有重要作用。本研究通过对泥河湾盆地NHA钻孔(175.2~106.0 m段)上新世-更新世过渡时期(2.89~1.78 Ma)333个沉积物样品的炭屑分析,并结合孢粉分析结果,揭示了泥河湾盆地上新世-更新世过渡时期野火活动历史,探讨了研究段内泥河湾盆地野火活动对区域气候、植被变化的响应特征以及野火强度与火频率的关系。研究结果显示:1)泥河湾盆地上新世-更新世过渡时期野火强度总体可以分为1个火强度较大的时期(2.74~2.32 Ma)和2个火强度较小的时期(2.89~2.74 Ma和2.32~1.78 Ma);2)炭屑总浓度以及>125μm粗粒炭屑浓度均表现出显著的41 ka斜率周期,表明泥河湾盆地野火活动强度受高纬冰量驱动影响显著;3)可燃生物量是影响野火强度的最主要因素,而植被类型对野火强度的影响较小;4)火强度与火频率的变化不完全同步,表现为强度大-频率高、强度大-频率低以及强度小-频率高的3种模式;5)2.60~2.14 Ma是研究段泥河湾盆地野火活动最强的时期,表现为火强度大-频率高,该时期泥河湾盆地受全球气候变冷影响,植被以针叶林为主,生物量较大,气候波动频繁,野火活动强;6)强度大-频率高的火活动模式通常出现在气候转型期或古地磁漂移事件期间,在2.60~2.56 Ma、2.15~2.14 Ma以及1.82~1.78 Ma出现的火强度和火频率峰值分别对应于Matuyama/Gauss古地磁倒转时期、Reunion正极性漂移事件以及Olduvai正极性漂移事件中后期,可能与古地磁倒转引起的气候波动变化导致泥河湾盆地野火活动增强有关。

关键词：泥河湾盆地上新世-更新世过渡时期炭屑火强度火频率

Relative pollen productivities of typical steppe species in northern China and their potential in past vegetation reconstruction

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Science China Earth Sciences 2014年第12期57卷 1254-1266页

作者： XU QingHai CAO XianYong TIAN Fang ZHANG ShengRui li yuecong li ManYue li Jie liU Yaoliang liANG Jian Institute of Nihewan Archaeology Hebei Normal University College of Resources and Environment Science Hebei Normal University Hebei Key Laboratory of Environmental Change andEcological Construction Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Research Unit Potsdam Potsdam 14473 Germany Institute of Earth and Environmental Sciences University of Potsdam

The Relative Pollen Productivities(RPPs)of common steppe species are estimated using Extended R-value(ERV)model based on pollen analysis and vegetation survey of 30 surface soil samples from typical steppe area of northern ***,Chenopodiaceae,Poaceae,Cyperaceae,and Asteraceae are the dominant pollen types in pollen assemblages,reflecting the typical steppe communities *** five dominant pollen types and six common types(Thalictrum,Iridaceae,Potentilla,Ephedra,Brassicaceae,and Ulmus)have strong wind transport abilities;the estimated Relevant Source Area of Pollen(RSAP)is ca.1000 m when the sediment basin radius is set at 0.5 ***,Artemisia,Brassicaceae,Chenopodiaceae,and Thalictrum have relative high RPPs;Poaceae,Cyperaceae,Potentilla,and Ephedra pollen have moderate RPPs;Asteraceae and Iridaceae have low *** reliability test of RPPs revealed that most of the RPPs are reliable in past vegetation ***,the RPPs of Asteraceae and Iridaceae are obviously underestimated,and those of Poaceae,Chenopodiaceae,and Ephedra are either slightly underestimated or slightly overestimated,suggesting that those RPPs should be considered with *** RPPs were applied to estimating plant abundances for two fossil pollen spectra(from the Lake Bayanchagan and Lake Haoluku)covering the Holocene in typical steppe area,using the"Regional Estimates of Vegetation Abundance from Large Sites"(REVEALS)*** RPPs-based vegetation reconstruction revealed that meadow-steppe dominated by Poaceae,Cyperaceae,and Artemisia plants flourished in this area before 6500–5600 cal yr BP,and then was replaced by present typical steppe.

关键词： typical steppe modern surface pollen relative pollen productivity relevant pollen source area paleovegetation

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Surface pollen assemblages as indicators of human impact in the warm temperate hilly areas of eastern China

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Chinese Science Bulletin 2011年第10期56卷 996-1004页

作者： DING Wei PANG RuiMing XU QingHai li yuecong CAO XianYong College of Resources and Environmental Sciences and Hebei Key Laboratory of Environmental Change and Ecological Construction HebeiNormal University Shijiazhuang 050016 China

Investigation of 78 surface pollen samples from warm temperate hilly areas of eastern China shows that pollen assemblages in areas of different land use are significantly *** concentrations in wastelands are higher than in plantations;these,in turn,are higher than in farmlands;implying that pollen concentration decreases with increasing human *** pollen dominated by Pinus and Quercus is common in all *** pollen percentages are higher while shrub pollen,fern spores and fern allies are lower in farmlands than in *** pollen is only detectable in and near farmlands;its percentages and concentrations decrease in *** and Cruciferae pollen percentages average 16.7% and 6.7% in farmland respectively,but Cereal reduces to less than 3% and Cruciferae to less than 0.5% in nearby *** coordinates analysis and clustering analysis indicate that pollen assemblages from farmlands are distinguishable from those under other vegetation *** of Poaceae,Chenopodiaceae,Artemisia,and Compositae pollen and Selaginella sinensis spores are closely related to human activities,and their types and frequencies indicate intensity of human *** spatial distribution of crops,Chenopodiaceae,and Artemisia reflects changes in both natural environments and human *** of cereal and Cruciferae pollen,for example,increase with decreasing altitude,but decrease with increasing *** pollen assemblages under artificial and human-disturbed vegetation in hilly areas may aid understanding of human impacts on the plains during the early-middle Holocene.

关键词：丘陵地区中国东部人类影响暖温带孢粉地表花粉浓度十字花科

Pollen flux and vertical dispersion in coniferous and deciduous broadleaved mixed forest in the Changbai Mountains

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Chinese Science Bulletin 2007年第11期52卷 1540-1544页

作者： XU QingHai li yuecong ZHOU liPing li YiYin ZHANG ZhenQing liN FengYou College of Resources and Environmental Sciences Hebei Normal University Shijiazhuang 050016 China College of Environmental Sciences Peking University Beijing 100871 China Changbaishan Forest Ecosystem Station of Chinese Academy of Sciences Antu 133613 China

The pollen flux in coniferous and deciduous broadleaved mixed forest in the Changbai Mountains is presented in one year's experiments. The results indicate that arboreal pollen percentages are more than 65% and pollen flux is higher than 5000 grain·cm-2·a-1,while less than 2% and lower than 1000 grain·cm-2·a-1 for shrubby pollen,and less than 20% and lower than 3000 grain·cm-1·a-1 for herbaceous pollen for most samples at different heights. The pollen assemblages are similar to those in the samples under 8 m height where Pinus and Ouercus are dominant and followed by the few non-local pollen types,and Fraxinus percentages are high with a few non-local pollen types at 16 m to 32 m height as well as non-local pollen clearly increased at 40 m height. Comparisons between pollen assemblages and vegetation composition suggest that similarities are higher for pollen trap samples than for surface moss samples.

关键词：长白山落叶植物森林花粉

Surface pollen assemblages of human-disturbed vegetation and their relationship with vegetation and climate in Northeast China

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Chinese Science Bulletin 2012年第5期57卷 535-547页

作者： li ManYue li yuecong XU QingHai PANG RuiMing DING Wei ZHANG ShengRui HE ZhiGuo College of Resources and Environment and Hebei Key Laboratory of Environmental Change and Ecological Construction Hebei Normal UniversityShijiazhuang 050024China

Pollen assemblages of 53 surface pollen samples from farmlands and wastelands in Northeast China were analyzed. Tree pollen percentages were usually higher than 30%, with Pinus (26.9%), Quercus (0.9%), Betula (0.9%) and Populus (0.7%) as the major types, and herb pollen percentages were usually higher than 50%, with weedy Poaceae (8.7%), Chenopodiaceae (7.1%), Artemisia (1.9%) and Compositae (3.5%) as the major taxa. Thus, the pollen assemblages were consistent with the regional vegetation compositions. However, there were differences in pollen assemblages among regions, especially among different geomorphological units. For example, in the mountains, there were more types of tree pollen and higher total percentages (average 42%) than in other areas, while cereal pollen percentages were lowest (11.2%). In the hills and high plains, herbs made up more than 60% of the pollens, with cereals (average 53.6%) the dominant type. In the low plains, pollen types were similar to those in the hills and high plains, but total pollen concentrations and the proportion of Concentricystes were much higher, while cereal pollen percentages were slightly lower (average 41.6%). Pollen assemblages in different land use types also differed. For example, in farmland, cereal pollen percentages were more than 40% and Chenopodiaceae was usually less than 2.5%, while in wasteland, weedy Poaceae was usually less than 10% and Chenopodiaceae was usually higher than 25%. Total pollen concentrations in farmland (average 3909 grains/g) were much lower than in wasteland (average 15074 grains/g). Redundancy analysis revealed that pollen assemblages were significantly negatively correlated with mean annual temperature (-0.73) and July mean temperature (-0.81) and significantly positively correlated with mean annual precipitation (0.48), indicating that pollen assemblages in the artificial or human-disturbed vegetation reflect regional climate well. Comparison of pollen assemblages in different areas o

关键词：中国东北地区花粉组合植被组成区域气候人为干扰年平均气温禾本科杂草花粉浓度

Surface pollen in the east of Qaidam Basin

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Journal of Geographical Sciences 2006年第4期16卷 439-446页

作者： CHEN Hui ZHAO Dongsheng LU Xinmiao li yuecong XU Qinghai li Shuangcheng OUYANG Hua College of Resources and Environment Sciences Hebei Normal University Shijiazhuang 050016 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China Institute of Tibetan Plateau Research CAS Beijing 100085 China College of Environmental Sciences Peking University Beijing 100871 China

Pollen analysis of 23 surface samples in the east of Qaidam Basin reveals the characteristics of pollen assemblages and their relationships with vegetation and climate. In pollen assemblages, Chenopodiaceae and Artemisia are preponderant types in all the samples, and Ephedra, Gramineae and Compositae are common types. The results of DCA （Detrended Correspondance Analysis） and Correlation Analysis show different pollen assemblages indicate different vegetations, coincided with respective vegetation types. A/C （Artemisia/Chenopodiaceae） in the desert can indicate the aridity. Depending on the aridity, the vegetation communities are divided into four groups： severe drought group, moderate drought group, slight drought group and tropophilous group. A/C value is less 0.2 in the severe drought group, 0.2-0.5 in the moderate drought group, 1.63 in the slight drought group and 5.72 slight-wetness group.

关键词： surface pollen Detrended Correlation Analysis A/C (Artemisia/Chenopodiaceae) values Qaidam Basin

Modern pollen assemblages and their relationships with vegetation and climate on the northern slopes of the Tianshan Mountains, Xinjiang, China

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Journal of Arid Land 2023年第3期15卷 327-343页

作者： ZHANG Wensheng AN Chengbang li yuecong ZHANG Yong LU Chao liU Luyu ZHANG Yanzhen ZHENG liyuan li Bing FU Yang DING Guoqiang Key Laboratory of Western China's Environmental Systems Ministry of EducationCollege of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China College of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China

The reconstruction of paleovegetation and paleoclimate requires an understanding of the relationships between surface pollen assemblages and modern vegetation and ***,we analyzed the characteristics of surface pollen assemblages across different vegetation zones in the Tianshan *** surface pollen analysis and vegetation sample surveys at 75 sites on the northern slopes of the Tianshan Mountains,we determined the correlation between the percentage of dominant pollen types and the corresponding vegetation *** analysis was used to investigate the relationships between surface pollen assemblages and environmental *** results show that the Tianshan Mountains contain several distinct ecological regions,which can be divided into five main vegetation zones from low to high altitudes:mountain desert zone(Hutubi County(HTB):500-1300 m;Qitai County(QT):1000-1600 m),mountain steppe zone(HTB:1400-1600 m;QT:1650-1800 m),mountain forest zone(HTB:1650-2525 m;QT:1850-2450 m),subalpine meadow zone(HTB:2550-2600 m;QT:2500-2600 m),and alpine mat vegetation zone(HTB:2625-2700 m;QT:2625-2750 m).The surface pollen assemblages of different vegetation zones can accurately reflect the characteristics of the mountainous vegetation patterns on the northern slopes of the Tianshan Mountains when excluding the widespread occurrence of Chenopodiaceae,Artemisia,and Picea *** average annual precipitation(P_(ann))and annual average temperature(T_(ann))affect the distribution of surface pollen ***,P_(ann) is the primary environmental factor affecting surface pollen assemblages in this region.A significant correlation exists between the pollen percentage and vegetation cover of Picea,Chenopodiaceae,Artemisia,and ***,Picea,Chenopodiaceae,and Artemisia pollen are over-represented compared with their corresponding vegetation *** Asteraceae pollen percentage roughly reflects the distribution of a species within the loc

关键词： surface pollen assemblages environmental factors vegetation cover redundancy analysis Tianshan Mountains

Influence of plant coverage and environmental variables on pollen productivities:evidence from northern China

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Frontiers of Earth Science 2020年第4期14卷 789-802页

作者： Kaixiu Zhang Wen Qin Fang Tian Xianyong Cao yuecong li Jule Xiao Wei Ding Ulrike Herzschuh Qinghai Xu College of Resource Environment and Tourism Beijing Key Laboratory of Resource Environment and GISCapital Normal UniversityBeijing100048China Key Laboratory of Alpine Ecology Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China Alpine Paleoecology and Human Adaptation Group(ALPHA) Key Laboratory of Alpine EcologyInstitute of Tibetan Plateau ResearchChinese Academy of Sciences(CAS)Beijing100101China College of Resources and Environment Sciences Hebei Normal UniversityShijiazhuang050024China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China Institute of Geological Sciences PalaeontologyFree University of BerlinBerlin12249Germany Alfred Wegener Institute Helmholtz Center for Polarand Marine Research Research Unit PotsdamPotsdam14473Germany Institute of Earth and Environmental Sciences University of PotsdamPotsdam14476Germany

Pollen productivity is a critical parameter in the interpretation of pollen-vegetation relationships,and in the quantitative reconstructions of past vegetation from fossil pollen ***-year monitoring records were collected for 143 pollen traps in various parts of northern China,together with modern vegetation *** Pollen Productivity Estimates(APPE)were calculated for 11 taxa using the ratio of pollen influx to plant coverage at each applicable sampling site,in which the plants of the target taxon were *** Pollen Productivity Estimates(RPPE)were calculated for the 11 taxa(taking Poaceae as the reference taxon)at those sites in which each taxon occurred together with *** and Chenopodiaceae were found to have the highest RPPEs and the largest RPPEs ranges,while Pinus and Quercus also had higher RPPEs than Poaceae;Abies,Betula,Larix,Picea and Cyperaceae had relatively low *** in RPPE between different areas may be explained by variations in climatic conditions,plant coverage and land use practices which might influence plant growing *** effect that variations in pollen productivity can have on vegetation reconstructions was demonstrated by applying these distinct RPPEs to reconstructions of Holocene vegetation in the Lake Daihai area(northern China),such as a large range of RPPE produces a large range of plant *** in RPPEs within a single taxon,related to vegetation coverage and climatic conditions,therefore need to be considered in future vegetation reconstructions.

关键词： pollen influx pollen productivity vegetation reconstruction REVEALS model northern China