Trace elements (TEs) could pose a potential threat to the environment and human health and hence they have been paid attention increasingly at present. 

Tibetan Plateau (TP) is the most glacier-concentrated area besides the Polar Regions. Widely distributed glaciers across the TP provide a unique opportunity for more in-depth studies over the TP, especially on the regional level. 

In recent decades, efforts have revealed that some TEs in several glaciers from the TP have been affected by anthropogenic activities. However, the information available on the assessment of TEs impact is still very limited due to the difficulty of field sampling and the samples are easily contaminated during sampling and pre-treating. 

Recently, the scientists from the Northwest Institute of Eco-Environment and Resources of Chinese Academy of Sciences investigate the potential sources and regional difference in the transport of TEs over the TP, and evaluate whether these regions are affected by the human activities and the degree of pollution of TEs.

In this study, scientists presented the acid-leached concentrations of TEs and dust content sampled from certain glaciers on the TP. A non-parametric Jonckheere-Terpstra Method was used to test the trend of spatial distribution of TEs. 

The statistical analysis indicated that TEs were the highest in the Qiumianleike (QMLK) glacier, lowest in the yuzhufeng (YZF) glacier, and comparable in the other three glaciers. 

Comparison with other glaciers of the plateau, the statistical analysis on As, Cu, Mo, Pb, and Sb shows that their concentrations had, in general, a decreasing distribution characteristic from the north to the south of TP, which indicated that the northern TP is loading more atmospheric-polluted impurity than central and southern TP. 

Enrichment factor (EF) analysis indicates that Rb, V, U, Cr, Ba, Cs, Li, As, Co, Mn, Tl, Sr, and Cu originated mainly from crustal dust, while anthropogenic inputs such as nonferrous metals melting, coal combustion, and traffic emission made an important contribution to the Mo, Pb, and Sb. 

In addition, evidences from air mass back trajectories also show that TEs in the five studied glaciers might not only come from surrounding areas of glaciers but also might be long-range transported by atmosphere from the Central Asia and South Asia and deposited on these glaciers. 

This study has been published on the Environment Science and Pollution Research in an article entitled “Spatial variations and sources of trace elements in recent snow from glaciers at the Tibetan Plateau”. 

Location map showing the Qiumianleike (QMLK),Meikuang (MK), Yuzhufeng (YZF), Xiaodongkemadi (XDKMD), and Gurenhekou (GRHK) (Image by LI Yuefang)