Quantitative assessment of the erosion and deposition effects of landslide-dam outburst flood, Eastern Himalaya.

Both regular flow and infrequent outburst floods shape the mountain landscape, but their relative contributions have been widely debated, in part due to the paucity of quantitative data on historical outburst floods. In June 2000, an outburst flood was triggered by a landslide-dam failure in a rapidly exhumed region of the Eastern Himalaya. To investigate the role of this kind outburst flood on landscape evolution, we employ topographic differencing, satellite imagery, and 2D hydraulic simulations to quantify the equivalent erosion and deposition within ~ 80 km flood route downstream of the breach.

The constancy of chemical weathering intensity on hillslopes in the arid to semiarid Qilian Mountains, NE Tibetan Plateau.

Quantifying the relationship between the chemical weathering and denudation rates of active orogenic belts over a range of climates is the key to addressing the controversy over the uplift-weathering hypothesis. However, studies have focused on warm and humid environments and have not examined cold and arid environments. Here, we present a new dataset of the chemical depletion fraction (CDF: ratio of the chemical weathering rate to the total denudation rate) across the arid to semiarid Qilian Mountains on the northeastern Tibetan Plateau, where the uplift-weathering hypothesis has been proposed.

Did the modern Yellow River form at the Mid-Pleistocene transition?

The incision of the Sanmen Gorge marks the birth of the modern Yellow River, but its timing varies from the late Miocene-early Pliocene to the late Pleistocene (∼0.15 Ma), and the suggested forcing mechanisms vary from the uplift of the Tibetan Plateau to global climate change. Here, we report sedimentologic, geochronologic, and provenance data from a drill core near the Sanmen Gorge, the last gorge along the main course of the Yellow River.

Heavy metals in the riverbed surface sediment of the Yellow River, China.

One hundred and eleven riverbed surface sediment (RSS) samples were collected to determine the heavy metal concentration throughout the Inner Mongolia reach of the Yellow River (IMYR), which has been subjected to rapid economic and industrial development over the past several decades. Comprehensive analysis of heavy metal contamination, including the enrichment factor, geo-accumulation index, contamination factor, pollution load index, risk index, principal component analysis (PCA), hierarchical cluster analysis (HCA), and Pearson correlation analysis, was performed. The results demonstrated that a low ecological risk with a moderate level of heavy metal contamination was present in the IMYR due to the risk index (RI) being less than 150 and the pollution load index (PLI) being above 1, and the averaged concentrations of Co, Cr, Cu, Mn, Ni, Ti, V, and Zn in the RSS, with standard deviations, were 144 ± 69, 77.

Phosphorus in the catchment of high sediment load river: A case of the Yellow River, China.

Surface sediment samples concurrently collected in the catchment of the Ningxia-Inner Mongolian reach of Yellow River (NIMYR) were analyzed to determine the phosphorus and correlated physiochemical properties of sediments. Samples were obtained from three main areas: the riverbed surface sediment (RSS), the floodplain surface sediment (FSS) and the desert surface sediment (DSS). The sequence of phosphorus-contamination level in this catchment, determined by a cumulative distribution function and multivariate statistical analysis, were FSS>RSS>DSS.

Loess Plateau storage of Northeastern Tibetan Plateau-derived Yellow River sediment.

Marine accumulations of terrigenous sediment are widely assumed to accurately record climatic- and tectonic-controlled mountain denudation and play an important role in understanding late Cenozoic mountain uplift and global cooling. Underpinning this is the assumption that the majority of sediment eroded from hinterland orogenic belts is transported to and ultimately stored in marine basins with little lag between erosion and deposition. Here we use a detailed and multi-technique sedimentary provenance dataset from the Yellow River to show that substantial amounts of sediment eroded from Northeast Tibet and carried by the river's upper reach are stored in the Chinese Loess Plateau and the western Mu Us desert.

Distribution features and controls of heavy metals in surface sediments from the riverbed of the Ningxia-Inner Mongolian reaches, Yellow River, China.

Fifty-six riverbed surface sediment (RSS) samples were collected along the Ningxia-Inner Mongolian reaches of the Yellow River (NIMYR). These samples were analyzed to determine their heavy metal concentrations (Co, Cr, Ni, Cu, V and Zn), grain sizes, sediment sources and the causes of their heavy metal contamination. The cumulative distribution functions of the heavy metals in RSS of these reaches are plotted to identify the geochemical baseline level (GBL) of each element and determine the average background concentration of each heavy metal.