Using δD as a proxy for paleo-environmental reconstruction: A good choice to sample at the site dominated by woods.

Some studies have demonstrated that leaf wax δD values for a single species varied significantly with seasons. However, it is still not clear that the seasonality patterns of leaf wax δD values in higher plants. Meanwhile, few efforts have been pursued to assess the effect of the light slopes (sunny vs. cloudy) on leaf wax δD values. In this study, we systematically investigated plant wax δD values and soil n-alkane δD values along different light slopes in different seasons (spring vs. autumn), as well as the relationship of n-alkane δD values between plant leaves and soil. We found that plant wax δD values were D-enriched by ca. 20‰ in spring relative to autumn, and ca. 10‰ in the sunny slope than in the cloudy slope. Moreover, surface soil n-alkane δD values varied consistently with plant wax δD values for different seasons and light slopes. More importantly, plant wax δD values showed clear seasonal variations, but varied slightly with light slopes. The variations of plant wax δD values can be recorded in soil n-alkane δD values. In addition, we found that leaf wax δD values in a majority of species differed significantly among woods, non-woods and grasses at a site. Therefore, we suggested a good choice to sample at the site dominated by woods when leaf wax δD values are utilized as a proxy for the reconstruction of the paleoenvironment.