全新世中国东部亚热带地区气候变迁的古生物学证据

中国东部亚热带地区全新世期间的气候波动频繁,引起哺乳动物群的多次迁徙。该时期哺乳动物群的常见种属多见于亚热带地区,仅少数种属如貘、犀、长臂猿和亚洲象等在自然状态下主要分布于热带―中亚热带南部地区,指示了具热带气候性质的中亚热带南部的森林环境。文章在确定中国东部全新世不同阶段此类动物群的种属构成与分布特征的基础上,主要根据热带种的迁徙和分布特征,初步推断各阶段亚热带地区的气候变迁状况如下：盛冰期之后的冰消期,温度逐渐回升,14 000―12 000 a BP时,热带种分布北界大致南移2°,指示1月平均气温较今低3~5℃;12 000―8 500 a BP为升温期,气候转暖,热带种分布北界达中亚热带南部,逐渐类似于现今气候;8 500―5 000 a BP为大暖期,热带种分布北界抵秦岭―淮河一线,北移约6°,指示1月气温较今高约7~9℃;5 000―3 000 a BP为降温期,热带种分布北界位于秦岭―淮河以南的长江流域,北移约4°,指示1月气温较今高约5~6℃;3 000 a BP以来,气候逐渐变冷。这些变化体现了中国东部亚热带地区在全新世时期发生了多次较大的气候和生物气候带变迁事件。     

A preliminary study of natural environmental change and its impact on early Late Paleolithic people in the northeast central Korean Peninsula during Marine Istope Stage 3 (40–30k cal a bp)

We comprehensively analyzed sediments obtained from an archeological excavation. A trench sediment profile of Maedun Cave (MC), South Korea, was analyzed geoarchaeologically. Multi-proxy analyses (palynomorphs, grain size, magnetic susceptibility, animal bones and artifacts) reflected the vegetation, hydroclimate and lives of prehistoric people at Marine Isotope Stage (MIS) 3 (ca. 40–30k cal a bp ) in the early Late Paleolithic. The palynoflora consisted of pollen and non-pollen palynomorphs. Under the air-circulation system in the cave, anemophilous pollen flowed in during the day, whereas waterborne pollen and spores, and freshwater algae, were transported by flooding during the summer monsoon rainy season. Mixed conifer and deciduous broad-leaved forest with an understory of pteridophytes flourished around the north-east central Korean Peninsula during MIS 3. Freshwater algae and grass pollen records may reflect precipitation intensity. It is assumed that they had flowed in during flooding caused by high precipitation during the enhanced East Asian summer monsoon, corresponding to Dansgaard–Oeschger (D/O) events 5 and 8 of δ¹⁸O GISP2 and Hulu Cave. The prehistoric people hunted herbivorous animals in the area around MC and sheltered inside it seasonally. They also used the grains of oats growing near the dwelling as a source of food.