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植硅体形态鉴定与组合分析广泛应用于古环境重建和农作物起源分析等。鉴于植硅体的抗腐蚀、抗降解,易保存,锢囚的碳不易污染,且保存了植物的原始信息等特性,其有机地球化学研究日益被重视。植硅体稳定同位素分析表明植硅体是植物通过吸收单硅酸,以蒸腾作用为主要动力,在植物的不同部位发生同位素分馏淀积形成,其稳定同位素组成具有丰富的植物生理和环境信息。植物不同部位植硅体稳定同位素组成具有差异,其含量和硅、氧同位素值沿蒸腾流通常有增加的趋势。沉积物植硅体碳同位素分析不仅可以用于恢复草本的C3、C4植物生物量的比例,并且有可能重建古大气的碳同位素构成,是三者中最具有潜力的考古学、古环境研究的指标。植硅体有机化学组成分析,特别是类脂物分析,有利于认识植硅体碳同位素值相对于总有机碳偏负,C3、C4草本植硅体同位素差值范围缩小的原因。
Silicate morphological identification and combination analysis is widely used in paleoenvironment reconstruction and crop origin analysis. In view of the anti-corrosion, anti-degradation, easy-to-save and occluded carbon of phytoliths that are not easily contaminated and preserve the original information of plants, their organic geochemistry has attracted more and more attention. Stable isotope analysis of phytoliths indicates that phytoliths are plants that absorb monosilicic acid and transpiration as the main driving force. They are formed by isotopic fractional deposition in different parts of the plant, and their stable isotopic composition is rich in plant physiological and environmental information. Stable isotopic compositions of phytoliths in different parts of plants are different, and their content and silicon and oxygen isotope values tend to increase along transpiration flow. Sediments carbon isotope analysis of phytoliths not only can be used to restore the proportion of herbaceous C3 and C4 plant biomass, and it is possible to reconstruct the ancient carbon isotope composition of the atmosphere, which is one of the three most potential archaeological and paleoenvironmental studies index. Organic chemical composition analysis of phytoliths, especially lipid analysis, is conducive to understanding the carbon isotope value of phytoliths relative to the total organic carbon and the reasons for the narrowing of the isotopic range of C3 and C4 herbaceous silicide bodies.