巽他陆架末次冰期植被之谜  

The mystery of the Sunda shelf vegetation during the last glacial period

作　　者：郁金勇 李丽[1] 贺娟[1] 贾国东[1] YU Jinyong;LI Li;HE Juan;JIA Guodong(State Key Laboratory of Marine Geology,School of Ocean and Earth Sciences,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学海洋与地球科学学院,海洋地质国家重点实验室,上海200092

出　　处：《海洋地质与第四纪地质》2021年第4期129-141,共13页Marine Geology & Quaternary Geology

基　　金：国家重点研发计划“国际大洋钻探南海航次后科学研究”(2018YFE0202402);国家自然科学基金“南海沉积物中支链四醚膜脂的组成和碳同位素特征及其对古气候研究的启示”(41673042),“晚渐新世—中中新世东亚低纬区降水演化历史及其全球影响”(41876042),“长江口外藻类生物标志化合物氢同位素与海洋盐度关系的研究”(41776049);上海市科委国际合作项目“国际大洋钻探计划合作研究”(20590780200)。

摘　　要：末次冰期低海平面时期出露的巽他陆架植被变化对全球碳循环影响有着重要影响,但目前植被重建结果仍存在很大争议。利用巽他陆架区域现有末次冰期的碳同位素和植物孢粉记录进行了古植被重建。与全新世相比,末次冰期时热带雨林的分布范围向赤道方向收缩,呈现不均匀的带状分布,而远离赤道的区域草本植物扩张。赤道辐合带的向南移动和热带太平洋的类El Niño状态导致的巽他陆架区域整体降水减少是造成这种现象的重要原因。山地在冰期植被垂直分布结构的演化中起着重要作用。在湿而冷的区域,山地雨林向下扩展;而在干而冷的区域,山地扮演着雨林避难所的角色。巽他陆架古植被重建工作仍面临着隐域性植被、植被指标局限性等难点。Changes in the vegetation of the Sunda shelf exposed during the last ice period at low sea level have important implications for global carbon cycle impacts.However,the results of current vegetation reconstructions are still highly controversial.A paleo-vegetation reconstruction was conducted using the available carbon isotope and pollen records of the last ice age in the Sunda shelf region.Compared to the Holocene,the distribution range of tropical rainforests contracted toward the equator during the last glacial period,showing an uneven zonal distribution pattern,while the herbaceous vegetation expanded in the regions far from the equator.The southward shift of the Intertropical Convergence Zone and the overall decrease of precipitation in the Sunda shelf region due to the El Niño-like state of the tropical Pacific Ocean are important reasons for this phenomenon.Mountains play an essential role in the evolution of the vertical distribution structure of vegetation during the ice age.In the wet and cold regions,montane rainforests expanded downward,while in the dry and cold regions,mountains played the role of rainforest refuges.The reconstruction of ancient vegetation on the Sunda shelf still faces difficulties such as cryptic vegetation and limitations of vegetation indicators,and more work is needed to improve it.

关 键 词：古植被 碳同位素 孢粉记录 巽他陆架 末次冰期 

分 类 号：P736.2[天文地球—海洋地质]