Effects of plant types on terrestrial leaf wax long-chain n-alkane biomarkers: Implications and paleoapplications

Terrestrial leaf wax n-alkane biomarkers provide considerable insights into paleoenvironmental reconstruction. Over decades, a substantial number of field investigations were performed to constrain hydroclimatic factors that influence leaf wax n-alkane biomarkers to improve their utility for paleoenvironmental applications. However, a critical issue, the plant type effects, does exist which potentially affects the fidelity of leaf wax n-alkane bio-markers for paleohydroclimate calibration. Here we review the effects of plant types on terrestrial leaf wax n- alkane biomarkers from three aspects: leaf wax n-alkane distribution (wood vs. non-wood), hydrogen isotope (delta H-2(wax); dicot vs. monocot) and carbon isotope (delta C-13(wax); C-3 vs. C-4) biomarkers. Then we demonstrate the re-lationships between three forms of leaf wax n-alkane biomarkers, and provide examples of the cross-calibration among them in paleo-applications. The in-depth review of plant type effects on leaf wax n-alkane biomarkers will be helpful to interpret the hydroclimate and vegetation signals in the geologic past.

Automated summary

Terrestrial leaf wax n-alkane biomarkers play a significant role in paleoenvironmental reconstruction, but the effects of plant types on their accuracy are important. This review examines the impact of plant types on leaf wax n-alkane biomarkers, including their distribution, hydrogen isotope composition, and carbon isotope composition, and provides examples of cross-calibration in paleo-applications.