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高等植物类脂物广泛分布于土壤、河流和湖泊沉积物中,正构烷烃是植物类脂物的重要组成部分。高等陆生植物叶蜡正构烷烃具有较长的链长(nC_(27)-nC_(33))以及明显的奇偶优势(CPI>5),其氢同位素组成在一定程度上反映了大气降水的同位素特征,对古高程重建具有重要的指示意义。不同地区的现代土壤正构烷烃氢同位素随高程的递减率有所不同,说明地区性的校正是必要的。蒸散富集作用和生物合成作用过程也会影响正构烷烃氢同位素值。在利用长链正构烷烃重建古高程时,需结合古气候、古纬度、古植被等多方面资料综合分析。
Higher plant lipids are widely distributed in soils, rivers and lake sediments, and n-alkanes are an important part of plant lipids. The higher ternary plant paraffin wax n-alkane has longer chain length (nC_ (27) -nC_ (33)) and obvious odd-even advantage (CPI> 5). The hydrogen isotope composition of the higher terrestrial plant wax reflects the precipitation Isotope characteristics of ancient elevation reconstruction has important significance. Different regions of modern soil normal paraffin hydrogen isotopes with the elevation of the rate of decline is different, indicating that the regional correction is necessary. Evapotranspiration enrichment and biosynthesis processes also affect n-alkane hydrogen isotope values. In the use of long-chain n-alkanes to rebuild paleo-elevations, a combination of paleoclimate, paleo-latitude and ancient vegetation should be taken into consideration.