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在中国黄土区,第四纪气候的冷暖交替表现为沉积事件和成壤事件的更迭.近年来,黄土地层研究的一个重要进展是查明了2.5Ma以来至少有37个大的土壤地层单位,并在空间上基本可以对比.当时从地层学角度考虑,没有将发育程度弱于当地全新世土壤的古土壤划分出来,同时未考虑古土壤的多周期特性,即多个成壤期的特征叠置或部分叠置于同一剖面形成复合古土壤.这类古土壤作为一个地层单元而实际上代表多个气候阶段.气候事件的鉴别和地层单位的划分是两个不同的概念.随着古气候研究的进一步深入,鉴别各种时间尺度的气候事件对理解气候演化及其动力因素和过程显得越来越为重要.虽然全新世土壤SO在类型上与其他古土壤不同,但发育程度相当高.那些发育程度低于SO的古
In the loess area of China, the warm and cold alternations of the Quaternary climate show the alternation of sedimentary events and pedogenesis events.An important progress of loess strata research in recent years is that at least 37 large soil strata units have been identified since 2.5 Ma, At the time, from the aspect of stratigraphy, the ancient soil with less developed degree than the local Holocene soils was not divided, and the multi-period characteristics of paleosol Or partly superimposed on the same section to form compound paleosol.The ancient soil as a unit of strata actually represents a number of climatic stages.The identification of climatic events and the division of strata are two different concepts.With the paleoclimate Further research and identification of climatic events at various timescales have become more and more important for understanding climate evolution and its dynamics and processes.Although the SO in the Holocene is different in type from other paleo-soils, it is highly developed. Those who developed less than the ancient SO