苏拉威西海周边地区全新世植被演化及气候变化

Vegetation and Climate Changes around Celebes Sea during Holocene

全新世时期的环境和气候变化是全球气候模拟、预测中不可或缺的资料.对苏拉威西海西北部MD98-2178孔（3.6200°N,118.7000°E,水深1 984m）全新世的样品进行孢粉分析和浮游有孔虫氧稳定同位素测试,重建全新世苏拉威西海周边地区植被演化和气候变化图景.根据孢粉记录得到：在全新世早期至7ka BP时,各孢粉组合浓度剧烈下降,指示海平面处于上升阶段;在7-4ka BP时,各孢粉组合浓度都处于低谷,体现为高海平面期;在4ka BP之后,孢粉记录则显示海平面有小幅的下降.在全新世中期,即5-4ka BP,热带高山雨林花粉含量明显上升,表明是温度低值期.蕨类孢子记录显示降雨量在全新世早期是持续增加的,但在全新世中期之后,降雨量有所减少,这与陆地孢粉记录和印尼石笋记录的结果相似,体现全新世该地区降雨量受海陆格局和太阳活动共同影响。

The environment and climate information during the Holocene is indispensable data for the global climate modeling and forecasting.Scenarios of regional vegetation and climate changes around the Celebes Sea during the Holocene are explored based on the alynological and oxygen isotope records of core MD98-2178（3.6200°N,118.7000°E;1 984 m water depth）from the northwest Celebes Sea in this study.Sea-level changes are discussed since the marine pollen record of core MD98-2178 is considered as an indicator.The sharp decline in concentration of all pollen groups during the Early Holocene,~10-7ka BP,indicates a sea-level rise.All pollen groups at 7-4ka BP suggest sustaining of a high sea-level.The marine pollen record after4 ka BP shows a slight fall of sea-level.The significant increase in pollen percentage of the tropical montane forest during the Middle Holocene,5-4ka BP,suggests a much cold condition along the Celebes Sea at the time.It is suggested that precipitation along the Celebes Sea has been affected by variations of land-ocean distribution and solar activities.It is implied by fluctuation in fern spores record that precipitation was at a high level during the Early Holocene,but lowered after the Middle Holocene,which is in a similar pattern as indicated by the Indonesian stalagmite records.