黄土有机碳同位素与古气候植被定量化研究进展

Reviews on the Quantitatively Reconstructing Paleoclimate and Paleovegetation Based on Carbon Isotope of Soil Organic Matter on Chinese Loess Plateau

定量化重建黄土高原地区的古气候和古植被,是黄土研究的新方向和趋势。利用黄土δ13Corg值定量化恢复古植被的研究已经比较多,而定量化恢复古降水则是一种较新的尝试。土壤δ13Corg值与植被相对生物量以及气候参数之间的关系机制比较清楚,根据土壤δ13Corg值重建的古降水和古植被状况是可接受的。针对研究中存在的一些问题,提出以后应重点加强不同生态条件下植物转化为有机质过程中的碳同位素分馏研究,多因素综合探讨其它气候和环境要素与土壤δ13Corg值之间的关系,使定量化研究更加准确。

It is a new research direction to quantitatively reconstruct the paleoclimate and paleovegetation on Chinese Loess Plateau. Carbon isotopes of organic matter of loess/paleosol sequences have been widely used in quantitative reconstruction of paleovegetation. However, it is a new attempt to quantitatively reconstruct the paleoprecipitation by soil δ13Corg values. Because the relationships between the carbon isotopes of soil organic matter and the biomass and the climate are relatively clear, therefore, it is reliable to reconstruct the paleovegetation and paleoprecipitation from soil δ13Corg analyses. Since some problems still exist in the quantitative investigation of the past climatic changes, the following works should be paid attention to in the future： （1） the carbon isotopic fractionation during vegetation turnover to soil organic matter in the different ecosystems, and （2） the relationship between more climatic and environmental factors and the soil δ13Corg values.