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Water resource is the primary factor impacting socio-economic development and security in arid Central Asia where high water stress occurs. Therefore, understanding the mechanism of water resource, particularly its associations with global warming, has unique importance for regional sustainable development. However, the dynamics of water resource is far from constrained in arid Central Asia indicated by the observed heterogenous trends of both alpine glaciers in high mountains (water tower) and river runoffs (dominant freshwater sources). Both meltwater and precipitations have been assumed to be the major contribution to the river runoff. Here, we make a systematic analysis on the 10Be exposure ages of the moraines in the high mountains and river terraces across Central Asia (n = 1057) to characterize the past changes of alpine glaciers and river discharges. The results show that the high river discharges are coupled with the alpine glacier expansions on both orbital and millennial scales, indicating a dominant contribution of meltwater to the freshwater supply. Both high river discharges and alpine glacier expansions occurred during the cold periods of the past 130 ka in Central Asia, indicating relatively low water stress under low-temperature conditions. This characteristic suggests that the water stress would increase with the decrease in both water reservoir and river discharges, and thus the environment would become drying with global warming in Central Asia. [ABSTRACT FROM AUTHOR]

The Sichuan-Tibet Railway in eastern Tibet runs across numerous seismogenic faults with high seismic risks. The Lancangjiang fault (LCJF), one of the essential strike-slip faults within the Qiangtang block, traverses the railway. However, the geometry and late Quaternary activities of the LCJF remain unclear, limiting the assessment of seismic hazards on the Sichuan-Tibet Railway and the understanding of kinematic patterns in eastern Tibet. Based on the interpretation of high-resolution satellite imagery, field observations, and shallow geophysical exploration, we first mapped the detailed geometry of the northern LCJF. It consists of two branches: Yangda-Yaxu fault (YYF) and Baqing-Leiwuqi fault (BLF), which merge eastwards onto the main LCJF. Displaced landforms and multiple numerical dating techniques reveal that the YYF is a mainly sinistral fault with a late Quaternary slip rate of ~2.2 + 0.6/−0.5 mm/yr and a minor vertical component (~0.1 mm/yr). The BLF undergoes an oblique motion with a left-lateral slip rate of ~1.2 + 0.5/−0.3 mm/yr and a northeast-vergent reverse rate of ~1.2 + 0.4/−0.2 mm/yr in the Holocene. Vector analysis of slip rates suggests that the LCJF has a sinistral rate of ~3.5 + 1.1/−0.8 mm/yr with a reverse component of ~1.6 + 0.4/−0.3 mm/yr, displaying an essential role in strain partitioning of eastern Tibet. Together with slip rates of other intra-block faults, the kinematic pattern of eastern Tibet probably applies to the sub-block model. Offset geologic units yield a total displacement of ~10–11 km for the YYF. Using the slip rate of the YYF, the LCJF was initiated at ~5.9–3.9 Ma, probably related to the establishment of the present-day strain pattern and the onset of crustal thickening in eastern Tibet during the late Miocene. In addition, the active YYF and BLF across the Sichuan-Tibet Railway have a seismic potential of Mw ~7.2–7.3 that will produce a ~ 1.8–2.0 m sinistral slip on the YYF, and a ~ 2.0 m horizontal, and ~ 1.1–1.3 m reverse motion on the BLF. They will pose a high seismic hazard potential on the railway. This study provides quantitative data for regional seismic hazard analysis and shows insights into the deformation mechanism of the plateau. • The geometry of the northern LCJF is first mapped. • The northern LCJF has a late Quaternary ~3.5 mm/yr sinistral and ~ 1.6 mm/yr reverse rate. • The seismic potential of the northern LCJF on the Sichuan-Tibet Railway is estimated. • The LCJF takes an important role in strain partitioning in eastern Tibet. • The initiation of the LCJF is related to the late-Miocene tectonic event in eastern Tibet. [ABSTRACT FROM AUTHOR]

An integrated analysis has been carried out on two cores dated by combination of 210Pb and 137Cs in order to characterize the extent of heavy metal accumulation in the Liaodong Bay, Northern China. The concentrations and burial fluxes of Zn, Pb, Cd, and Hg increased abruptly after late 1970s. The enrichment factors of Cd, Hg, Zn and Pb are more than 30, 10, 7, and 3.5, respectively, in the surface sediments. Coincident to the increase of heavy metal contents, the decreasing trend of 206Pb/207Pb ratio indicated lead in the surface sediments mainly come from anthropogenic activities. [Copyright &y& Elsevier]