Biomass and fossil-fuel combustion history in the Osaka Plain, based on charcoal and spheroidal carbonaceous particles(SCPs) records of the latest Pleistocene and Holocene sediments

自然和人为的燃烧过程调动了各种各样的环境材料。本文研究了日本中部大阪平原最新更新世和全新世沉积物中的宏观和微观碳颗粒和球形碳质颗粒（SCPs）。木炭颗粒是通过生物质燃烧产生的。scp是由化石燃料的不完全高温燃烧形成的。根据最新更新世和全新世沉积物的木炭地层学，将最后12ka划分为3个时期：12ka ~ 9ka、9ka ~ 2ka和2ka以后。木炭丰度从12 ka开始增加，11 ka ~ 9 ka之间的木炭丰度最高，与古代人类活动有关。9ka后，木炭丰度逐渐减小，从2ka到现在逐渐增加。沉积物中的木炭丰度证据表明，大阪平原的生物质火灾频率变化受到古代人类活动的影响。全新世晚期沉积物中scp浓度在20世纪30年代初增加。此后，scp浓度在20世纪50年代迅速上升，70年代至今呈下降趋势。这些趋势可分别归因于工业活动的增长和对大气污染物排放的管制。

Natural and anthropogenic combustion processes mobilize a large variety of materials about the environment. In this study, macroscopic and microscopic charcoal particles, and spheroidal carbonaceous particles (SCPs) in the latest Pleistocene and Holocene sediments of the Osaka Plain, central Japan, were studied. Charcoal particles are generated through biomass burning. SCPs are formed from incomplete high temperature combustion of fossil fuels.Based on the charcoal stratigraphy of the latest Pleistocene and Holocene sediments, the last 12ka is divided into three periods : 12 ka to 9 ka, 9 ka to 2 ka and since 2 ka. Charcoal abundance increased from about 12 ka, and the highest abundance of charcoal between 11 ka and 9 ka was associated with the ancient human activities. After 9ka, charcoal abundance decreased and increased gradually from 2 ka to present. Conquently, charcoal abundance evidence in the sediments suggests that variation of biomass fire frequency in the Osaka Plain was affected by ancient human activities.SCPs concentration in the latest Holocene sediments increased in the early 1930s. After that SCPs concentration increased rapidly in 1950s and decreased from 1970s to present. These trends can ascribed to the growth of industial activities and the regulation of atomospheric pollutant emission, respectively.