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以陕西渭南黄土剖面２１ｋａ以来的黄土样品为研究对象，获得了元素碳浓度及δ１３Ｃ值随深度（时间）分布曲线．元素碳浓度在 ２０．１６， １７．７６， １１．９７和 ４．４９ｋａ时期呈现峰值，这几个时段均属气候快速变化时期．其中，１１．９７和 ２０．１６ｋａ时期的峰值较大，时间跨度约为几十年至几百年，可能代表短期的强度较大的古火灾事件．元素碳的δ１３Ｃ值变化范围为－１１．７１‰～－２１．３４‰，主要反映Ｃ４植物的同位素组成特征，表明当时黄土高原植被类型以草原为主．
The loess samples from 21 ka of Weinan loess section in Shaanxi Province were taken as the research object, and the distribution curves of elemental carbon concentration and δ13C value with depth (time) were obtained. Elemental carbon concentrations peaked at 20.16, 17.76, 11.97 and 4.49 ka periods, all during periods of rapid climate change. Among them, the peaks of 11.97 and 20.16 ka periods are large with a time span of about several decades to several hundred years, which may represent short-term intense ancient fire events. The δ13C value of elemental carbon varied from -11.71 ‰ to -21.34 ‰, mainly reflecting the isotopic composition of C4 plants, indicating that the main vegetation types in the Loess Plateau were grassland.