中国中全新世植被带迁移的气候动力学机制探讨

地球轨道参数驱动的太阳辐射变化造成了中全新世北半球大陆夏季的普遍增温，但中低纬度的冬季温度低于现代。古气候模型和古植被模型在这个动力驱动基础上，对东亚季风区的票据均反映了北半球中低纬度的冬季温度低于现代，由此主要受冬季温度控制的中纬度森林植被向南迁移。然而，根据花粉资料重建的中全民植被表明，中国东部森林植被带向北迁移，其中常绿阔叶林北移３００ｋｍ，落叶阔叶林北移５００～６００ｋｍ。根据古植被类比研

STUDIES OF THE CLIMATIC DYNAMICS FOR THE MIDHOLOCENE VEGETATIONAL CHANGES IN CHINA

The orbit forcing theory suggests that the insolation at 6ka was lower than at the present in winter season in low and middle latitudes. This driving climate has been simulated by palaeo GCMs showing a lower than present winter temperature in East Asian. The palaeoclimate driven vegetation has been simulated by biome models showing the mid Holocene forest vegetation was shifted southwards in China. However, the palaeovegetation reconstructed by a great of pollen records displays the forest zones migration systematically northwards when compared with the present. These vegetation patterns are used to furthermore reconstructed the climate which reflect a warmer than present winter in China. As there existed huge different or contrasting results between geological observations and model simulations, we recognized that dynamic mechanisms can not be only limited in the orbit forcing. The land surface feedback in Asian monsoon regions could play a greater important role than direct insolation anomaly.