Cosomogenic isotope production and global carbon cycles during the past 10,000 years

产生余弦的放射性核素^<14>C主要是由宇宙射线与氮的相互作用在地球大气中产生的。由于宇宙射线通量受到地磁和日磁屏蔽的调制，^<14>C的记录提供了过去太阳活动和地磁场强度变化的信息。^<14>氧化后，CO_2（放射性碳）成为全球碳循环的组成部分，并在大气、生物圈和海洋之间进行交换。因此，对过去大气^<14>C浓度的分析提供了探测全球碳循环变化的可能性。然而，由于大气^<14>CO_2浓度对^<14>C产率的变化很敏感，我们需要从独立数据中验证过去的产率。在这项研究中，我们把重点放在宇宙产生的放射性核素上，^<10>Be，作为痕量的。pastproduction变化。在本研究中，我们旨在通过比较^<14>C浓度和^<10>Be丰度来研究过去的碳循环。一般来说，过去的^<10>Be重建是通过冰芯分析进行的。我们从湖泊沉积和泥炭沉积等陆相沉积中重建了^<10>的Be变化。随着湖泊沉积物10Be分析研究的深入，湖泊沉积物的^<10>Be浓度明显受到地表^<10>Be循环的强烈影响；材料的供应来自大气和河流。基于这一事实，我们在此完成以下解释成一份报告；发展了陆地沉积物中Be浓度^<10>的方法，推广了摆动匹配法确定沉积速率，通过对琵琵湖岩心的分析，得到了地表Be浓度^<10>的方法。

The cosinogenic radionuclide ^<14>C is produced in the Earth's atmosphere mainly by the interaction of cosmic rays with nitrogen. Since the cosmic ray flux is modulated by geo-and heliomagnetic shieldings, records of ^<14>C provide information on variations in the solar activity and the geomagnetic field intensity in the past, After oxidation to ^<14>CO_2 (radiocarbon) becomes a constituent of the global carbon cycle, and exchanges between atmosphere, biosphere and the ocean. The analysis of the past atmospheric ^<14>C concentration therefore provides the possibility to detect change of global carbon cycle. However, since the atmospheric ^<14>CO_2 concentration is sensitive to changes in the ^<14>C production rate, we need to verify the past production rate from the independent data. In this study, we focused on a cosmogenic radionuclide, ^<10>Be, as a trace of.pastproduction changes.In this study, we aimed to investigate the past carbon cycle by the comparison of ^<14>C concentration with ^<10>Be abundance. In general, the past ^<10>Be reconstructions have carried out from ice core analyses. We had an approach to reconstruct the ^<10>Be change from the terrestrial deposition such as lake sediment and peat depositions with higher sedimentation rate. As research marches on 10Be analysis of the lake sediments, it became very obvious that the ^<10>Be concentration of the lake sediments can be strongly influenced by the ^<10>Be cycle on the earth's surface ; supply of the material form atmosphere and river. Based on the this fact, we here complete following interpretation into a report ; developed method of ^<10>Be concentration of the terrestrial sediments, extended wiggle matching method to determine the sedimentation rate, ^<10>Be on the earth's surface based on the analysis of a core from the lake Biwa.