Biosynthetic hydrogen isotopic fractionation factors during lipid synthesis in submerged aquatic macrophytes: Effect of groundwater discharge and salinity

摘要

Highlights?Hydrogen isotopic fractionation forPotamogetongrown in a lake and lab measured.?δD values for plants collected from a lake unaffected by groundwater.?δD values of plants grown in the lab became lower at higher salinity.?Average ε value ?136±9‰ for freshwater samples.AbstractSedimentary lipid biomarkers have become widely used tools for reconstructing past climatic and ecological changes due to their ubiquitous occurrence in lake sediments. In particular, the hydrogen isotopic composition (expressed as δD values) of leaf wax lipids derived from terrestrial plants has been a focus of research during the last two decades and the understanding of competing environmental and plant physiological factors influencing the δD values has greatly improved. Comparatively less attention has been paid to lipid biomarkers derived from aquatic plants, although these compounds are abundant i