Tree-ring δ<sup>15</sup>N of Qinghai spruce in the central Qilian Mountains of China: Is pre-treatment of wood samples necessary?

WANG Ziyi, LIU Xiaohong, WANG Keyi, ZENG Xiaomin, ZHANG Yu, GE Wensen, KANG Huhu, LU Qiangqiang

Journal of Arid Land . 2022, (6): 673 -690 . DOI: 10.1007/s40333-022-0065-1