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利用中国第四纪孢粉数据库提供的 116个 6kaBP (± 5 0 0年 )和 39个 18kaBP (± 2ka)的花粉数据 ,根据生物群区化方法 (biomization)重建了中国中全新世 (6kaBP)和未次盛冰期 (18kaBP)两个关键时段的生物群区。结果表明 ,中全新世东部森林系统地向北推进 ,温带落叶阔叶林向北推进约 4个纬度。大部分森林明显向草原区推进 ,青藏高原的冻原大面积退缩 ,在西南地区局部和热带地区气候较今略为冷湿 ,热带季雨林转变为热带雨林。末次盛冰期 ,草原大面积向南扩张 ,抵达现代的常绿阔叶林区的北缘 ,热带森林消失 ,常绿阔叶林退缩到现代热带区域边缘。
Using 116 pollen data of 6 kaBP (± 5000) and 39 18kaBP (± 2 ka) provided by the Quaternary Sporopollen Database in China, the mid-Holocene (6 kaBP) And the unsuspecting ice age (18kaBP) in two key periods of biota. The results show that the Central Eastern Holocene forest system to promote the north, temperate deciduous broad-leaved forest to the north about 4 latitude. Most of the forests were obviously advanced to the prairie areas. The tundra on the Qinghai-Tibet Plateau shrank in a large area. The climate in the southwestern part of China and the tropics was slightly cold and wet today, and the tropical monsoon forest turned into a tropical rain forest. During the last glaciation, the vast area of grassland expanded southward, reaching the northern edge of the modern evergreen broad-leaved forest area. Tropical forests disappeared and the evergreen broad-leaved forest receded to the edge of the modern tropical region.