[目的]研究磁化率在亚洲季风区河口海岸环境中的变化及其指示意义.[方法]利用珠江口沉积物柱状样HKUV16,结合放射性碳定年,重建近8000 a来沉积物的磁化率变化.[结果]距今8000～3000 a磁化率呈现下降趋势,表明随着东亚夏季风减弱,输送到珠江口的陆源沉积物减少.而从距今2500 a开始,HKUV16磁化率显著上升,在距今400 a达到最大2700×10-6SI.[结论]该变化趋势与近2000 a以来珠江流域人类活动的增加以及夏季风的变强一致,近2000 a来人类活动对珠江口环境的影响已逐渐超过了夏季风等自然因素带来的变化.%[Objective]To study changes and its application of MS in the coastal and estuarine environments in the Asian monsoon regions.[Method]Sediment core HKUV16 collected from the Pearl River Estuary (PRE) was used to reconstruct magnetic susceptibility changes over the last 8 thousands years with age controlled by radiocarbon dating.[Result]The results showed prominent decreasing trend from 8000 to 3000 years BP which suggested less terrestrial material imput to the PRE under the background of weakening of East Asian summer monsoon. The MS of HKUV16 increased significantly from 2500 to 400 years BP when the MS reached the peak value 2700×10-6SI. Changes of MS since 2000 years BP coincided with the expansion of human activities in the Pearl River drainage area, as well as the intensified summer monsoon.[Conclusion]It suggested human activities has been exerting increasingly impact on the PRE environment over the last 2000 years than natural factors such as the summer monsoon. The results of this study could provide good reference for further application of MS in environment and climate reconstructions in coastal and estuarine areas.
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