Characteristics and climate significance of surface sediments in the Horqin Sandy Land
As a product of arid climate,deserts record rich information about climate and environmental chang-es.The climate environment indicated by the characteristics of desert aeolian sediments varies under different re-gional conditions.In this study,we selected a total of 25 sample points from east to west in the Horqin Sandy Land,and the chromaticity index,DRS and magnetic susceptibility were analyzed to explore the spatial varia-tion characteristics of aeolian sediments on the sandy surface.At the same time,the climate significance of vari-ous proxy indicators in the context of regional modern climate factors is discussed.The results show that the chro-maticity characteristics of surface wind-sand sediments in Horqin Sandy Land are closely related to regional pre-cipitation.L*,a*and b*/a*can be used as proxy indicators to indicate regional climate.The goethite and hema-tite in surface sediments are at low levels,and changes in Gt/Hm can indicate the overall trend of dry and wet cli-mate conditions.The xfd％value of surface wind-sand sediments can be used as a proxy indicator of regional pre-cipitation.The magnetic enhancement of sediments is mainly due to the strengthening of weathering and pedogen-esis caused by the increase of precipitation intensity,which leads to the production of a large number of fine-grained ferromagnetic minerals.Generally speaking,the chromaticity,magnetic susceptibility and goethite to he-matite ratio of surface aeolian sediments in Horqin sandy land can effectively indicate the regional climate and en-vironment.This study deepens the relationship between surface sedimentation and climatic parameters in North-east China from the perspective of modern process,and provides an important reference for the reconstruction of paleoclimate change history in Northeast China.
surface sedimentchromaticitygoethite to hematite ratiomagnetic susceptibilityclimate signifi-cance
NETL
NSTL
万方数据
