南极罗斯海末次冰盛期以来的古生产力变迁  

Evolution of paleoproductivity in the Antarctica Ross Sea since the Last Glacial Maximum

作　　者：龙飞江 向波 王逸卓 张泳聪 胡良明 孙曦 陆正元 武文栋 葛倩 边叶萍 韩喜彬 LONG Feijiang;XIANG Bo;WANG Yizhuo;ZHANG Yongcong;HU Liangming;SUN Xi;LU Zhengyuan;WU Wendong;GE Qian;BIAN Yeping;HAN Xibin(Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China;Second Institute of Oceanography,Ministry of Natural Resources,Hangzhou 310012,China;Key Laboratory of Submarine Geosciences,Ministry of Natural Resources,Hangzhou 310012,China;School of Mechanical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]成都理工大学沉积地质研究院,成都610059 [2]自然资源部第二海洋研究所,杭州310012 [3]自然资源部海底科学重点实验室,杭州310012 [4]上海交通大学机械与动力工程学院,上海200240

出　　处：《海洋地质与第四纪地质》2024年第1期109-120,共12页Marine Geology & Quaternary Geology

基　　金：国家重点研发计划“战略性能源金属矿产的深海原位快速探测技术与设备(2022YFC2905500)”;南极专项“南极重点海域对气候变化的响应和影响(IRASCC2020-2022)”;中央级公益性科研院所基本科研业务费专项资金项目“图们江河口地形变化监测及沉积环境演变研究”(SZ2102);上海交通大学“深蓝计划”基金“深海环境中基于等离子体声学特征的定量化激光诱导分解光谱方法”(SL2002)。

摘　　要：研究罗斯海古生产力的目的在于揭示南极地区过去的气候变化和生态系统演变,为预测未来气候变化影响和提高气候模型准确性提供关键信息。通过对南极罗斯海ANT32-RB16C岩芯沉积物的有机碳、氮及同位素和主、微量元素等测试分析,重建了自24.8 cal.kaBP(末次冰盛期)以来的罗斯海研究区古生产力演变史。结果显示,ANT32-RB16C站位的沉积记录较好地反映了罗斯海在末次冰盛期、末次冰消期与全新世的古生产力变化情况,该地古生产力的演变趋势与南极地区的气温变化基本一致,整体表现为在温暖时期较高、寒冷时期较低的特征:24.8~17.5 cal.kaBP,海洋生产力较低;17.5~11.7 cal.kaBP,海洋生产力由低到高转变;11.7~0 cal.kaBP,海洋生产力逐渐恢复。罗斯海古生产力的演变受地区气候变化的影响较为明显,尤其是南极冷反转、新仙女木与小冰期等几次气候变化事件对研究区古生产力的影响较大。同时,海冰与营养盐含量的变化等也是影响罗斯海末次盛冰期以来古生产力演变的重要因素:在冷期,研究区的海冰覆盖及表层水分层增强,导致富含营养盐的深层水的上升减缓;同时表层海水中的硝酸盐等物质相对缺乏,海洋生产力总体较低。To reveal the past climate changes and ecological system evolution in Antarctica and provide key information,predict the impact of future climate change,and improve the accuracy of climate models,the Ross Sea paleoproductivity was studied by testing and analyzing the organic carbon,nitrogen and their isotopes,and major and trace elements of the ANT32-RB16C core in the Antarctic Ross Sea.The evolution of paleoproductivity in the Ross Sea since 24.8 cal.kaBP(Last Glacial Maximum)was reconstructed.Results show that the ANT32-RB16C sedimentation record well reflected the change in paleoproductivity in three stages including the Last Glacial Maximum,the last deglaciation,and the Holocene,which is consistent with the change in temperature in the Antarctica.The core record shows a higher productivity during the warm period and a lower productivity during the cold period.Specifically,from 24.8 to 17.5 cal.kaBP,the ocean productivity was low,from 17.5 to 11.7 cal.kaBP,the ocean productivity changed from low to high status,and during 11.7~0 cal.kaBP,the ocean productivity gradually recovered.The paleoproductivity of the Ross Sea was influenced obviously by regional climate change,especially climate events such as the Antarctic Circumpolar Reversal,Younger Dryas,and Little Ice Age etc.,which had a heavy impact on the evolution of paleoproductivity in the study area.At the same time,sea ice,nutrients,and so on play important roles in the evolution of paleoproductivity in the Ross Sea.In other words,during the cold period,sea ice coverage increased and the thickness of surface seawater layer slowed down the upwelling of deep water rich in nutrient salt.Meanwhile,there was a relative lack of nitrates in surface seawater,resulting in lower productivity at that time.

关 键 词：海洋生产力 海冰 末次冰盛期 南极罗斯海 

分 类 号：P736.2[天文地球—海洋地质]