通过测定宁夏长城塬全新世黄土-土壤剖面中的元素含量,获得了一些地球化学参数指标。这些化学参数作为良好的气候代用指标,与磁化率、频率磁化率形成很好的对比,表明:古土壤形成时期气候温暖湿润,降雨丰富,淋溶作用强烈,黄土堆积时期气候相对干冷,成壤作用微弱;黄土风化成壤过程中元素的迁移变化可以间接反映出全新世以来的气候变化及成壤环境的变化。通过研究元素的活动性,发现全新世宁夏长城塬黄土只经历了早期的化学风化,应处在脱Ca、Na阶段,尚未进入去K风化阶段。
Through the analysis of macro- and micro-elements and their variations with XRF at the CCY loess-soil site, Ningxia Hui Autonomous Region, we obtain a number of geochemical parameters. There is a good comparison between these chemical parameters and magnetic susceptibility, frequency dependent susceptibility, which indicates that during the paleosol formation, the climate was warm and humid with abundant precipitation and greater eluviation, while during the loess accumulation, the climate was relatively cold and arid with weak pedogenesis. And the variation of elements can indirectly reflect the change of climate and pedogenic environment during the process of loess chemical weathering. Through the research of the activities of elements in CCY profile, it was found that Holocene loess in CCY only experienced primary process of chemical weathering characterized by leaching of Ca, Na, and not reached the secondary process characterized by leaching of K.
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