不同纬度黄土-古土壤赤铁矿含量差异及其气候指示意义——基于漫反射光谱和色度方法  

Variation in Hematite Content in Loess-Paleosol at Different Latitudes and Its Climatic Significance:Based on Diffuse Reflectance Spectroscopy and Chromaticity Methods

作　　者：李嘉伟 吕镔[1,2,3] LI Jiawei;L Bin(Key Laboratory for Humid Subtropical Ecogeographical Processes of the Ministry of Education,Fujian Normal University,Fuzhou 350117,China;School of Geographical Sciences/School of Carbon Neutrality Future Technology,Fujian Normal University,Fuzhou 350117,China;Institute of Geography,Fujian Normal University,Fuzhou 350117,China)

机构地区：[1]福建师范大学湿润亚热带生态-地理过程教育部重点实验室,福建福州350117 [2]福建师范大学地理科学学院/碳中和未来技术学院,福建福州350117 [3]福建师范大学地理研究所,福建福州350117

出　　处：《福建师范大学学报（自然科学版）》2024年第4期1-10,共10页Journal of Fujian Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(42130507、42277442)。

摘　　要：在全球变暖的背景下,北极和第三极(青藏高原)的增温幅度高于世界上其他地区,其增温幅度和机制并不明晰,因此有必要开展不同时间尺度、不同气候记录载体的研究。利用赤铁矿研究末次间冰期-末次冰期的增温效应,使用漫反射光谱和色度方法量化俄罗斯西伯利亚、中国黄土高原西峰和中国川西高原甘孜3个沉积连续的黄土-古土壤序列中的赤铁矿,揭示其蕴含的气候信息。研究结果显示:(1)漫反射光谱和色度方法相结合是定量赤铁矿的有效方法。(2)在大空间尺度中,赤铁矿主要受控于温度而非降水。(3)在末次间冰期和末次冰期旋回时期,较高纬度气温变化幅度大于较低纬度气温变化幅度。不同纬度的气温“轨道尺度较差”可能是轨道尺度太阳辐射差异和年内太阳辐射差异的综合体现。In the context of global warming,the warming amplitude of the Arctic and the Third Pole(Tibetan Plateau)exceeds that of the rest of the world,yet their warming amplitude and mechanism remain unclear.Therefore,it is imperative to study different climate recorders over different time scales.This paper employs hematite to study the warming effects from the last interglacial to the last glacial period.Diffuse reflectance spectroscopy and chromaticity methods are used to quantify the hematite in three continuous loess-paleosol sequences deposited in Siberia,Russia,Xifeng on China s Loess Plateau,and Ganzi in the western Sichuan Plateau,revealing the climate information contained within.The results show that:(1)The combination of diffuse reflectance spectroscopy and chromaticity method is an effective way to quantify hematite.(2)At large spatial scales,hematite is mainly influenced by temperature rather than precipitation.(3)During the last interglacial and glacial cycles,the range of temperature change was greater at higher latitudes than at lower latitudes.The“orbital-scale disparity”in temperatures at different latitudes may be a comprehensive reflection of the differences in orbital-scale solar radiation and intra-annual solar radiation variations.

关 键 词：漫反射光谱 色度 黄土-古土壤 赤铁矿 不同纬度 

分 类 号：P318[天文地球—固体地球物理学]