引用本文: | 李育,王乃昂,李卓仑.甘肃石羊河流域猪野泽湖泊沉积物粒度敏感组分与花粉组合关系.湖泊科学,2011,23(2):295-302. DOI:10.18307/2011.0221 |
| LI Yu,WANG Nai'ang,LI Zhuolun.Relationship between grain-size sensitive components and pollen assemblages in the lake sediments of Lake Zhuye, Shiyang River Basin, Gansu Province. J. Lake Sci.2011,23(2):295-302. DOI:10.18307/2011.0221 |
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摘要: |
在石羊河终端湖猪野泽全新世探井剖面, 对连续不同间距368组和74组样品, 进行粒度测量与花粉分析.结果表明, 沉积物不同粒度敏感组分与典型花粉组合有很好的相关性.花粉总浓度及麻黄(Ephedra)、白刺(Nitraria)、藜科(Che-nopodiaceae)、香蒲属(Typha)、云杉属(Picea)的花粉百分比与小于89.3lμm三个粒度范围的敏感组分存在正相关关系, 与大于89.31μm两个粒度范围的组分存在负相关关系.桦木(Betula)、栎(Quercus)、荨麻属(Urtica)的花粉百分比与大于89.31μm三种粒度敏感组分存在明显正相关关系.沉积物花粉组合与粒度敏感组分之间相关关系, 主要受控于流域水分条件及相应的湖泊水位, 同时也受到流域风沙活动的影响.沉积物中与细颗粒组分正相关关系的花粉指标, 主要受到较好的流域水动力条件和高湖面的影响;而与粗颗粒正相关的花粉指标, 则与低湖面及风沙作用有关.当流域水分较好, 终端湖水位较高的时期, 总花粉浓度及河流传播的花粉百分含量较高;流域气候较干燥时期, 总花粉浓度较低, 风媒花粉的百分含量较高.最后, 本文结合猪野泽湖泊沉积物粒度敏感组分与花粉组合的关系, 将猪野泽地Ⅸ晚冰期以来的气候、环境变化过程分为6个阶段, 其中早、中全新世气候较湿润, 晚冰期及晚全新世期间气候相对较干燥。 |
关键词: 猪野泽 湖泊沉积物 粒度敏感组分 花粉组合 石羊河流域 |
DOI:10.18307/2011.0221 |
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基金项目:国家自然科学基金项目(41001116)和兰州大学中央高校基本科研业务专项资金(1zujbky-2010-99)联合资助 |
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Relationship between grain-size sensitive components and pollen assemblages in the lake sediments of Lake Zhuye, Shiyang River Basin, Gansu Province |
LI Yu, WANG Nai'ang, LI Zhuolun
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College of Earth and Environmental Sciences, Center for Hydrologic Cycle and Water Resources in Arid Region, Lanzhou University, Lanzhou 130000, P.R.China
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Abstract: |
We hand-excavated a profile named QTH02 in a terminal lake in Shiyang River, Lake Zhuye.The QTH02 was sampled at 2cm intervals in which 368 samples were yielded for analysis of grain-size, and sampled at 10cm intervals in which 74 samples were yielded for pollen analysis.Based on the correlation analysis, the results showed that the variables between sensitive components of the grain-size and pollen assemblages are related with each other.The total pollen concentration and percentages of Ephedra, Nitraria, Chenopodiaceae, Typha and Picea are positively correlated with the grain-size sensitive components that the sizes are less than 89.31μm, and negatively correlated with the grain-size sensitive components that the sizes are larger than 89.31 μm.The percentages of Betula, Quercu, and Urtica are positively correlated the grain-size sensitive components that the sizes are more than 89.31μm.The correlation between the pollen assemblages and grain-size sensitive components is mainly controlled by the moisture conditions of the basin and water level of the Lake Zhuye, which is also affected by wind transportation.The pollen proxies which are correlated with the fine components are mainly affected by the hydrodynamics of the drainage basin and high lake-level, and the pollen proxies which are correlated with the coarse components are mainly affected by low lake-level and eolian activities.While the drainage basin is relatively humid and the lake-level is relatively high, the total pollen concentration and percentages of river-transported pollen are relatively high.While the drainage basin is relatively arid, the total pollen concentration is relatively low, but the percentages of wind-transported pollen are relatively high.Then, based on the relationships between the grain-size sensitive components and polien assemblages, we divided the climatic and environmental changes in Lake Zhuye since the Late Clacial into six stages.The climate is moist in the Early and Middle Holocene but dry in the Late Clacial and Late Holocene. |
Key words: Lake Zhuye lacustrine sediments sensitive grain-size to environments pollen assemblages Shiyang River Basin |