A Novel Tracer Technique to Quantify the Lithogenic Input Flux of Trace Elements to Qinghai Lake

作者：Pu Zhang, Xuezheng Pei, Chenyang Cao, Chi Chen, Ziqin Gong, Xuerou Li, Xuerou Li, Jingya Pang, Lihua Liang, Xiangzhong Li, Xiangzhong Li, Youfeng Ning, R. Lawrence Edwards · 发表于：Frontiers in Earth Science · 年份：2022 · DOI：10.3389/feart.2022.866314 · 被引用次数：5 · 研究领域：Groundwater and Isotope Geochemistry、Geology and Paleoclimatology Research、Geochemistry and Geologic Mapping

Thorium (Th) isotopes were applied to quantify the contributions of lithogenic inputs to the Qinghai Lake (QHH). Concentrations of dissolved 232 Th and 230 Th were measured in 59 water samples collected from Qinghai Lake and its exogenous recharge rivers. There are significant differences in the concentration of 232 Th of the sampled water in QHH that confirm the input of variable lithogenic material sources. The 230 Th concentrations were used to calculate a scavenging residence time for Th, which was then applied to calculate the flux of dissolved 232 Th by matching the measured concentrations of dissolved 232 Th. Then the 232 Th content of lithogenic material was used with the solubility of Th from the preliminary particle data from the Qinghai–Qaidam district. When using a Th solubility from particles of 1%, the fluxes of lithogenic material range from 0.03 to 25.25 g/m 2 /yr in the surface water, consistent with the flux results of settled particles from the previous study. When a large number of exogenous recharge rivers are mixed into the northwest basin of Qinghai Lake, the 232 Th content and lithogenic flux of the lake water are mainly influenced by the type and content of the particles in the Buha and Shaliu rivers. Conversely, in south basin with limited recharging rivers, the 232 Th content of the lake water away from the estuary is mainly influenced by atmospheric dust. Furthermore, based on the 230 Th normalization method (combining with 232 Th and τ Th ), the B...