摘要
沙地和沙漠是干旱-半干旱地区重要的地质记录载体,其对气候变化十分敏感。明确位于东亚季风区松嫩沙地地表沉积物的气候代用指标与气候之间的耦合关系,对于深入理解松嫩沙地的气候环境演化具有重要意义。基于此,本研究在松嫩沙地广泛采集了66个地表沉积物样品(包括44个河流沙样品和22个风成沙样品),在此基础上进行了色度、赤铁矿/针铁矿、磁化率测试,并结合采样点的温度与降水参数,探讨了各气候代用指标的环境意义。结果表明:1)河流沙中a^(*)值和b^(*)值与降水呈负相关,可作为区域降水的有效代用指标;风成沙中a^(*)与降水、b^(*)与温度分别呈现出良好的正相关关系,分别指示了区域的降水和温度变化信息。2)针铁矿含量及赤铁矿/针铁矿比值(Hm/Gt)与温度具有较好的相关性,可作为温度变化的有效代用指标;而赤铁矿含量与降水表现为显著的负相关关系,反映了其对降水的敏感性。3)百分比频率磁化率(χ_(fd)%)与温度呈现良好的正相关性,可有效反映区域温度的变化;磁化率(χ_(lf))与气候的关系在河流沙与风成沙中存在差异,体现出沙地磁化率变化的复杂性和特殊性。利用沙地沉积物反映气候变化时,应注意区分河流沙和风成沙中气候代用指标的气候意义,使其揭示的气候信息更为准确。
Sandy land and desert are important geological record carriers in arid and semi-arid areas,which are sensitive to climate change.The coupling relationship between climate proxies and climate in the surface sediments of the Songnen sandy land in the East Asian monsoon region is of great significance for understanding the climate and environment evolution of the Songnen sandy land.Based on this,66 surface sediment samples(including 44 river sand samples and 22 aeolian sand samples)were widely collected in Songnen sandy land in this study.On this basis,the chromaticity,hematite/goethite and magnetic susceptibility tests were carried out,and the environmental significance of each climatic proxy index was discussed in combination with the temperature and precipitation parameters of the sampling points.The results show that:1)the values of a^(*) and b^(*) in river sand are negatively correlated with precipitation,which can be used as an effective proxy for regional precipitation.In the eolian sand,a^(*) and precipitation,b^(*) and temperature showed a good positive correlation,respectively,indicating the regional precipitation and temperature change information.2)The content of goethite and the ratio of hematite to goethite(Hm/Gt)have a good correlation with temperature,which can be used as an effective substitute index for temperature change.The hematite content showed a significant negative correlation with precipitation,reflecting its sensitivity to precipitation.3)The percentage frequency magnetic susceptibility(χ_(fd)%)has a good positive correlation with temperature,which can effectively reflect the change of regional temperature.The relationship between magnetic susceptibility(χ_(lf))and climate is different between river sand and aeolian sand,which reflects the complexity and particularity of the change of magnetic susceptibility in sandy land.When using sand sediments to reflect climate change,attention should be paid to distinguish the climatic significance of climate proxy indicators in river sand and aeolian sand,so as to make the climate information revealed more accurate.
作者
王蜜娇
迟云平
谢远云
康春国
汪烨辉
孙磊
吴鹏
刘若男
魏振宇
刘海金
Wang Mijiao;Chi Yunping;Xie Yuanyun;Kang Chunguo;Wang Yehui;Sun Lei;Wu Peng;Liu Ruonan;Wei Zhenyu;Liu Haijin(School of Geographical Sciences,Harbin Normal University,Harbin 150025;Geographical Environment Monitoring and Spatial Information Service in Cold Regions of Harbin Normal University Key Laboratory of Heilongjiang Province,Harbin 150025;Department of Geography,Harbin University,Harbin 150086)
出处
《地质科学》
CSCD
北大核心
2024年第6期1759-1774,共16页
Chinese Journal of Geology(Scientia Geologica Sinica)
基金
国家自然科学基金项目(编号:42171006,41601200)
黑龙江省自然科学基金项目(编号:ZD2023D003)
哈尔滨师范大学博士启动基金项目(编号:XKB201418)资助。
关键词
松嫩沙地
色度
赤铁矿/针铁矿
磁化率
气候
Songnen sandy land
Chromaticity
Hematite/gothite
Magnetic susceptibility
Climate
作者简介
王蜜娇,女,2000年生,硕士研究生,第四纪地质与环境演化专业。E-mail:2248361565@qq.com;通讯作者:迟云平,男,1982年生,博士,副教授,第四纪地质与环境演化专业。E-mail:1982cyp@163.com。
