Elucidation of changes in long-term environments and biological systems in the northeast Asia by the use of lake sediments in the Lake Baikal basin

我们研究了103万年来的长期古环境和生物系统在东北亚的生物标志物，包括植物色素，和化石花粉在沉积物中的核心，从库苏古尔在贝加尔湖盆地。沉积物样品的直接热解和甲基化与气相色谱-质谱联用（PyMeGCMS）技术相结合，建立了沉积物样品生物标志物的快速分析方法，重力岩心（X106、HV 05 ST 2、HV 05 ST 3）提供了末次冰期至今古环境和生物系统变化的详细信息。对岩芯的AMS测年（常规年龄）显示，沉积物的年龄小于24，000年。生物生产力在冰期的基础上总有机碳（TOC）的含量是非常低的，增加到博林-阿勒罗德（约。12，000 yBP），减少到新仙女木事件（约。11，000 yBP），然后再次增加到后冰期。稀有草本植物 ...更多信息 离子如链格孢属（Altemisia spp.）在冰川期，陆地上有大量的浮游生物分布，在常年冰盖下有少量的浮游生物分布。冰期后温暖时期，木本植物植被增加，湖泊浮游生物沿着增加。通过古地磁（Brunhes-Matuyama，Jaramillo Chron）测定了HDP 04柱样（80.0 m）的沉积年龄为103万年。岩芯TOC含量与海洋同位素年龄的相关性不好，反映的是流域局部气候变化，而不是全球气候变化。在过去的103万年中，除了全新世之外，霍夫哥尔湖的生物生产力相对较低，略低于贝加尔湖。库苏古尔湖的外源有机质的贡献远高于贝加尔湖，反映了库苏古尔湖可能是小流域。HV 05 ST 2沉积物柱样的PyMeGCMS分析结果表明，沉积物柱样中存在一系列脂肪酸和酚羧酸类化合物。这些化合物的模式是相似的那些化合物中发现的乙酸乙酯提取物的核心，揭示了PyMeGCMS是有用的，在沉积物中的生物标志物的快速测定。少

We studied changes in long-term paleoenvironment for 1.03 million years and biological systems in the northeast Asia by the use of biomarkers including plant pigments, and fossil pollens in sediment cores from Lake Hovsgol in the Lake Baikal basin. Direct pyrolysis and methylation of sediment samples combined with gas chromatography-mass spectrometry (PyMeGCMS) were, in addition, carried out to develop rapid analysis of biomarkers in the sediment cores.Gravity cores (X106, HV05ST2, HV05ST3) have detailed information on changes in paleoenvironment and biological systems during the last glacial period to the present. AMS dating (conventional age) of the cores showed sediment ages were less than 24,000 years. Biological production in the glacial period based on total organic carbon (TOC) contents was very low, increased to Bolling-Allerod (ca. 12,000 yBP), decreased to Younger Dryas event (ca. 11,000 yBP) and then increased again to the post glacial period. Scarce herbaceous plant vegetat … More ion such as Altemisia spp. on the land and small amount of plankton were distributed under perennial ice cover in the glacial period. Woody plant vegetation increased in the warm post glacial period, along with increase of lake plankton.Sedimentation ages of HDP04 sediment core (80.0 m) were determined 1.03 million years by paleomagnetism (Brunhes-Matuyama, Jaramillo Chron). Pattern of TOC contents of the core was well not correlated with that of marine isotope stages, reflects largely local climatic changes in the drainage basin rather than global climatic changes. Biological production in Lake Hovsgol was relatively low for the last 1.03 million years except for Holocene, and was somewhat lower than that of Lake Baikal. Contribution of allocthonous organic matter in Lake Hovsgol was much higher than that of Lake Baikal, reflecting probably small drainage basin of Lake Hovsgol. The presence of bacteriochlorophyls specific to brown-Chlorobium in the depths between 19-21 m of the core suggests strongly that lake bottom was anoxic due to the stagnant of the lake water.A series of fatty acids and phenolcarboxylic acid were detected in HV05ST2 sediment core by PyMeGCMS. The pattern of these compounds were similar to that of those compounds found in ethyl acetate extracts of the core, revealed that PyMeGCMS was useful for the rapid determination of biomarkers in the sediment core. Less