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Calibrating Vegetation Cover and Grassland Pollen Assemblages in the Flint Hills of Kansas, USA  [PDF]
Julie L. Commerford, Kendra K. McLauchlan, Shinya Sugita
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.47A1001
Abstract:

Grassland cover and composition respond to climate and have undoubtedly changed during the Holocene, but quantitative reconstructions from fossil pollen have been vague about spatial scale and taxon-specific cover. Here, we estimate the relevant source area of pollen for sedimentary basins approximately 50 m in radius, and we report pollen productivity estimates for 12 plant taxa in the tallgrass prairies of central North America. Both relevant source area of pollen and pollen productivity estimates were calculated via the Extended R-Value Model. To obtain these estimates, we collected and quantified the pollen found in surface sediment samples from 24 ponds across the study area. Vegetation was surveyed in the field in a 100 m radius around each pond, and vegetation maps from the Kansas Gap Analysis Project (GAP) were used to a radius of 2 km. Pollen fall speeds were calculated according to Stoke’s Law. Pollen assemblages from basins approximately 50 m in radius have a relevant source area of 1060 m in this grassland landscape. Pollen productivity estimates range from 0.02 to over 30 among the 12 taxa: Artemisia, Ambrosia, Asteraceae, Chenopodiaceae, Cornus, Fabaceae, Juniperus, Maclura, Poaceae, Populus, Quercus, and Salix. Woody taxa generally have higher pollen productivity than herbaceous taxa (except for Chenopodiaceae and Ambrosia

Modern pollen assemblages of the forest communities and their relationships with vegetation and climate in northern China

LI Yuecong,XU Qinghai,ZHANG Liyan,WANG Xueli,CAO Xianyong,YANG Xiaolan,

地理学报 , 2009,
Abstract: 53 pollen traps and surface samples were collected in order to detect the characteristics of pollen assemblages and their relationships with vegetation and climate in 16 forest communities located in 10 mountains in northern China. The results show that 72% of the pollen taxa (80 taxa) are the same between the traps and the surface samples. The dominant taxa in the plant communities are consistent with the main pollen taxa in the pollen assemblages at the same sites. In Pinus plant communities, both Pinus pollen influx and concentration are higher, indicating the high pollen productivity and good pollen preservation ability of Pinus. In Picea and Abies plant communities, Picea and Abies have lower pollen influxes but higher concentrations, suggesting their low pollen productivities but better pollen preservation abilities. In Betula and Quercus plant communities, Betula and Quercus have higher pollen influxes but lower concentrations, revealing their high pollen productivities but poor pollen preservation abilities. The study of relationships between pollen and vegetation with discriminant analysis shows that pollen assemblages from both trap and surface samples can reflect the characteristics of different communities and distinguish different ecological areas, but surface samples can reflect the dominant components of communities much better than the traps. The study on correlations between pollen assemblages and climate with DCCA reveals that significant correlations exist between pollen assemblages and mean temperature of the coldest month (r = 0.84 for trap samples, r = 0.72 for surface samples), and then annual mean precipitation (r = 0.73 for trap samples, r = 0.71 for surface samples).
Surface pollen assemblages as indicators of human impact in the warm temperate hilly areas of eastern China
Wei Ding,RuiMing Pang,QingHai Xu,YueCong Li,XianYong Cao
Chinese Science Bulletin , 2011, DOI: 10.1007/s11434-011-4350-1
Abstract: 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 different. Pollen concentrations in wastelands are higher than in plantations; these, in turn, are higher than in farmlands; implying that pollen concentration decreases with increasing human impact. Arboreal pollen dominated by Pinus and Quercus is common in all samples. Herbaceous pollen percentages are higher while shrub pollen, fern spores and fern allies are lower in farmlands than in wastelands. Crop pollen is only detectable in and near farmlands; its percentages and concentrations decrease in wastelands. Cereal 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 wastelands. Principle coordinates analysis and clustering analysis indicate that pollen assemblages from farmlands are distinguishable from those under other vegetation types. Occurrence 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 impact. The spatial distribution of crops, Chenopodiaceae, and Artemisia reflects changes in both natural environments and human activities. Percentages of cereal and Cruciferae pollen, for example, increase with decreasing altitude, but decrease with increasing latitude. Understanding 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.
Modern Pollen Assemblages of the Forest Communities and Their Relationships with Vegetation and Climate in Northern China
中国北方森林群落现代花粉与植被和气候的关系

LI Yuecong,XU Qinghai,WANG Xueli,CAO Xianyong,YANG Xiaolan,
李月丛
,许清海,王学丽,曹现勇,阳小兰

地理学报 , 2008,
Abstract: In this paper,53 pollen traps and surface samples were collected in order to detect the characteristics of pollen assemblages and their relationships with vegetation and climate in 16 forest communities located in 10 mountains in northern China.The results show that 72% of the pollen taxa(80 taxa) are the same between the traps and the surface samples.The dominant taxa in the plant communities are consistent with the main pollen taxa in the pollen assemblages at the same sites.In Pinus plant communities,both Pinus pollen influxes and concentrations are higher,indicating its higher pollen product and good pollen preservation ability.In Picea or Abies plant communities,Picea or Abies have lower pollen influx but high concentrations,suggesting their low pollen productivities but good pollen preservation abilities.In Betula or Quercus plant communities,Betula or Quercus have higher pollen influx but low concentrations,revealing their high pollen productivities but poor pollen preservation abilities.The study of the relationships between pollen and vegetation with discriminant analysis shows that pollen assemblages from both trap and surface samples can reflect the characters of different communities and distinguish different ecological areas,but the surface samples reflect the dominant components of communities much better than the traps.The study on the correlations between pollen assemblages and climate with DCCA reveals that significant correlations exist between pollen assemblages and mean temperature of the coldest month(R = 0.84 for trap samples,R = 0.72 for surface samples),and annual mean precipitation as well(R = 0.73 for trap samples,R = 0.71 for surface samples).
Pollen assemblages from different agricultural units and their spatial distribution in Anyang area
XueLi Wang,YueCong Li,QingHai Xu,XianYong Cao,LiYan Zhang,Fang Tian
Chinese Science Bulletin , 2010, DOI: 10.1007/s11434-009-0480-0
Abstract: Pollen analysis is one of the best and possible approaches for the quantitative reconstruction of paleobotany and paleoclimate, and discrimination of human activities. In 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 records. The 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 percentages. In general, pollen assemblages are consistent with vegetation composition, though some differences also exist in different agricultural units. In 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 rape-lands. Both pollen assemblages and PCoA can generally identify the vegetable plots, farmlands, woodlands, wastelands, and rape-lands. Pinus 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.
Pollen assemblages of major steppe communities in China
中国草原区主要群落类型花粉组合特征

LI Yue-Cong,
李月丛

生态学报 , 2005,
Abstract: Relationships between modern surface pollen and vegetation are essential for recovering past vegetation. In this paper, 39 sites covering various types of steppe in China were selected to study the relationships, at each sites, one surface soil sample was collected and vegetation investigations were carried out at the same time. The result shows that surface pollen assemblages reflect similar characteristics for all types of steppe vegetation in general. The percentages of arboreal pollen are less than 5% i...
ENVIRONMENTAL CHANGES OF THE YIN RUINS AREA BASED ON POLLEN ANALYSIS
殷墟地区土壤剖面孢粉组合特征及环境意义*

Zhang Zhenqing,Xu Qinghai,Li Yuecong,Yang Xiaolan,Jing Zhichun,Tang Jigen,
张振卿
,许清海,李月丛,阳小兰,荆志淳,唐际根

第四纪研究 , 2007,
Abstract: In order to understand the origin, flourishing and declining of the Yin Dynasty better, pollen analysis of three randomly disturbed natural soil profiles (Chadianpo, Guang 1 and Guang 2) have been derived near the sites of the Yin Ruins. The lithology of the profiles are similar, all consisting of grey-black paleo-soil layers formed before the Yin Dynasty at the bottom, and the upper different-colored sub-clay layers formed after the Yin Dynasty. Pollen assemblage of the gray-black paleo-soil in the Chadianpo profile was dominated (more than 60%) by arboreal pollen, such as Pinus, Juglans, Betula and so on. Pollen of herbs which was dominate by Artemisia, Compositae and Gramineae was much lower, no more than 30% in general. It implies that the paleo-vegetation in the vicinity of Anyang City was warm deciduous broad-leaved forest. The pollen assemblages of Guang 1 and Guang 2 in the Guangrunpo which is about 20km away to the southeast of the Anyang City, were similar to each other and both were dominated by herb pollen of mesophytes and hygrophytes, such as Typha, Cyperaceae, and Ranunculaceae, revealing that the paleo-vegetations were mainly marsh and grassland, which was different from the vicinity of the Anyang City at that time. Although the profiles of Guang 1 and Guang 2 are close to each other (only 1.6km apart), there were little differences between the pollen assemblages of the two profiles. There were much more mesophyte and hygrophyte herb pollen types like Cyperaceae and Ranunculaceae in Guang 2, which indicates that it was a little lower in elevation and much wetter than the location of Guang 1. In the upper parts of the gray-black paleo-soil, there were increasing contents of Gramineae and Selaginella sinensis pollen, which reveals that ancient humans have already dwelled here at that time, and the forests in the vicinity might have been destroyed by human activities. Above the gray-black paleo-soil in the Chadianpo profile, the arboreal pollen diminished sharply, rightly at the flourishing time of the Yin culture, suggesting a serious deforestation by ancient citizen for the construction of the city and daily life. A similar phenomenon could be found in the two profiles of Guangrunpo, the contents of arboreal pollen also decreased sharply at the boundary between the gray-black paleo-soil and the upper parts. The later diminishing of arboreal pollen and increasing of Selaginella sinensis from the three profiles revealed the process of the deforestation in Anyang and the western mountain areas.
Modern pollen-vegetation relationship based on discriminant analysis across an altitudinal transect on Gongga Mountain, eastern Tibetan Plateau
Quan Li,QuanSheng Ge,GuoBang Tong
Chinese Science Bulletin , 2012, DOI: 10.1007/s11434-012-5236-6
Abstract: Quantitative relationship between modern pollen assemblage and altitudinal vegetation belt is crucial for the reconstruction of paleovegetation in the mountain regions. Modern pollen analysis on 70 topsoil samples was conducted across an altitudinal transect (1100–4500 m) on the eastern slope of Gongga Mountain in the eastern Tibetan Plateau with an elevation interval of 50 m. Distributions of major pollen types along the transect indicated a weak correlation between Pinus pollen and the elevation. Distributions of Picea and Abies pollen (percentage sum of 2%–8%) could fairly indicate the elevation range of 2700–3700 m, as well as the subalpine dark coniferous forest and the timberline in the region. High percentage intervals of alpine types of Ericaceae, Cupressaceae and Cyperaceae were correlated to the high-elevation regions (3700–4500 m) dominated by alpine shrub meadow and alpine meadow. Seven altitudinal vegetation belts on the eastern slope of Gongga Mountain were well defined by discriminant analysis conducted on the modern pollen assemblages, as reflected by high values of probability of modern analog. Most of the modern pollen assemblages (88.5%) were typical for the vegetation types at their sampling locations. Thus, the relationship between the modern pollen assemblages and vegetation across the altitudinal transect based on discriminant analysis can be applied to the quantitative reconstruction of paleovegetation changes in the mountain regions of the eastern Tibetan Plateau.
黄河兰州段河水搬运花粉与累积花粉组合特征初步研究*
Preliminary study on assemblages characteristics of waterborne pollen and accumulated pollen from the Yellow River at Lanzhou station
 [PDF]

彭卫, 林雪如 ,黄小忠, 刘思丝 ,贾宛娜
- , 2016, DOI: 10.7605/gdlxb.2016.04.051
Abstract: 对从2011年9月至2012年6月在黄河兰州段采集的24个水样进行了孢粉分析,并探讨了河流搬运花粉组合随时间变化的特征以及累积花粉的组合状况。结果表明,河流中花粉组合和花粉浓度随时间具有明显的变化,春夏时段花粉组合以榆属、杨属、柳属和桦属等乔木花粉为主,秋冬时段以蒿属、藜科等草本花粉为主,且花粉浓度和河流含沙量有较好的正相关关系。根据河水流量与花粉浓度积分计算得出样品采集时段的累积花粉通量,其组合特征与各时间点的花粉组合具有明显的差异,表明单个时间节点花粉组合由于影响因素较多不能够反映流域植被状况,而累积花粉组合可以指示泥沙和花粉源区的植被状况。本研究中黄河兰州段河水搬运花粉可能指示黄河兰州段以上至刘家峡水库之间黄土区的植被情况。
Twenty-four water samples were collected from the Yellow River at Lanzhou station from September in 2011 to June in 2012. Based on the pollen analysis, the temporal change characteristics and accumulated pollen features of the waterborne pollen were discussed. The result shows that pollen assemblages and pollen concentration have obvious changes over time:Ulmus,Populus,Salix and Betula are the major components of the pollen assemblages in the spring and summer;and Artemisia and Chenopodiaceae are main species in the autumn and winter. Pollen concentration has a positive correlation with waterborne sediment concentration. There are obvious differences between pollen assemblages of individual samples and the accumulated pollen assemblage,and pollen assemblages of individual samples cannot reflect regional plant communities. Accumulated pollen assemblage can basically represent the vegetation status of loess area from Liujiaxia reservoir to Lanzhou where it is suggested to be the main pollen and sediment source area in this study site
Vegetation evolution and millennial-scale climatic fluctuations since Last Glacial Maximum in pollen record from northern South China Sea
Yunli Luo,Xiangjun Sun
Chinese Science Bulletin , 2005, DOI: 10.1007/BF03183681
Abstract: In order to study vegetation evolution and environmental change since the Last Glacial Maximum (LGM), a total of 180 pollen samples with an average time resolution of 150 years were analyzed on the top parts (0–31 m, 0–27 kaBP) of deep sea sediments from ODP Site 1144 (20°3.18’N, 1170°25.14’E), northeastern SCS. The character-istic features of pollen diagram include that pine dominates in the interglacial, and herb pollen dominates with a good deal of tropical-subtropical pollen in the last glacial, and from 18 kaBP the tropical-subtropical pollen influx rose abruptly, while the herbaceous pollen influx and percentage dropped quickly, indicating that climate turned warmer and more humid, and more tropical-subtropical vegetation grew on the mainland and the emerging continental shelf, while the grassland on the shelf diminished. A detailed comparison shows an earlier change of pollen assemblages at the glacialinterglacial transition between MIS6 and 5 (Termination II) than the ice volume change indicated by the oxygen isotope record, implying that mid-low latitude climate warming preceded ice sheet retreat. Millennial-scale climatic fluctuations of vegetation change in pollen record are also discussed.
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