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Fault segmentation plays a critical role in assessing seismic hazards, particularly in tectonically complex regions. The Laji-Jishi Shan Fault Zone (LJSFZ), located on the northeastern margin of the Tibetan Plateau, is a key structure that accommodates regional tectonic stress. This study integrates geomorphic indices, cross-fault deformation rate profiles, and 3D crustal electrical structure data to analyze the varying levels of tectonic activity across different segments of the LJSFZ. We extracted 160 drainage basins along the strike of the LJSFZ from a 30 m resolution digital elevation model and calculated geomorphic indices, including the hypsometric integral (HI), stream length-gradient index (SL), and channel steepness index (ksn), to assess the variations in tectonic activity intensity along the strike of the LJSFZ. The basins were categorized based on river flow directions to capture potential differences across the fault zone. Our results show that the eastern basins of the LJSFZ exhibit the strongest tectonic activity, demonstrated by significantly higher SL and ksn values compared to other regions. A detailed segmentation analysis along the northern Laji Shan Fault and eastern Jishi Shan Fault identified distinct fault segments characterized by variations in SL and ksn indices. Segments with high SL values (>500) correspond to higher crustal uplift rates (~3 mm/year), while segments with lower SL values exhibit lower uplift rates (~2 mm/year), as confirmed by cross-fault deformation profiles derived from GNSS and InSAR data. This correlation demonstrates that geomorphic indices effectively reflect fault activity intensity. Additionally, 3D crustal electrical structure data further indicate that highly conductive mid- to lower-crustal materials originating from the interior of the Tibetan Plateau are obstructed at segment L3 of the LJSFZ. This obstruction leads to localized intense uplift and enhanced fault activity. These findings suggest that while the regional stress–strain pattern of the northeastern Tibetan Plateau is the primary driver of the segmented activity along the Laji-Jishi Shan belt, the direction of localized crustal flow is a critical factor influencing fault activity segmentation. [ABSTRACT FROM AUTHOR]

Lake-terminating glaciers are among the most severely retreating glacier types in high mountain areas. However, the characteristic of being covered by glacial lakes after retreat makes it hard to estimate their actual ice loss in recent years, as does the contribution of different parts in ice loss, which leads to significant obstacles not only in evaluating solid water resources but understanding inter-relationships between glacial ice and glacial lakes. This study presents a detailed investigation of Jiongpu Co, one of the biggest glacial lakes in the Tibetan Plateau, including its bathymetry and area evolution. The ice loss in the last two decades was analyzed using a multisource DEM dataset. The main results showed that from 1976 to 2021, Jiongpu Co had expanded from 1.19 ± 0.09 km2 to 5.34 ± 0.07 km2. The volume of Jiongpu Co showed a surprising increment from 0.09 ± 0.004 Gt to 0.66 ± 0.03 Gt from 1976 to 2021, leading to a subaqueous equivalent ice loss of 0.32 ± 0.01 Gt water from 2000 to 2020 and resulting in an underestimated ice loss of 0.06 Gt, 19% compared with previous evaluations. The total ice loss of the Jiongpu glacier was 1.52 ± 0.37 Gt from 2000 to 2020, and more than 1/3 ice loss was related to lake expansion (0.32 ± 0.01 Gt underwater, 0.19 ± 0.02 Gt above water). This study makes a further contribution to the understanding of ice loss in the complicated system of lake-terminating glaciers. [ABSTRACT FROM AUTHOR]

El Niño‐Southern Oscillation (ENSO) is the most dominant interannual signal of climate variability and profoundly affects river flooding globally, especially in East Asia. However, ENSO also has ∼2,000 and ∼1,000‐year cycles, but due to the lack of flood records with sufficient length, little is known about the ENSO's impact on floods at these millennial timescales. Here we test this in the middle‐lower Yangtze River by reconstructing the first Holocene flood record with optically stimulated luminescence and 14C ages of flood deposits. We find the periods with high flooding probability generally correspond with intervals of weakened solar activity. Importantly, the flood record displays 2,000 and 1,000‐year cycles similar to the ENSO record, and band‐pass filter results show the two records are synchronous at these bands. Our results reveal a persistent control of ENSO on millennial‐scale hydroclimatic variability in the Yangtze basin and likely other basins. Plain Language Summary: El Niño‐Southern Oscillation (ENSO) is the prominent pattern of interannual climate variability, profoundly affecting the river flow and flooding at the global scale. However, the ENSO's interannual cycle was strongly damped or even non‐existent in most of the Holocene, compared with a more robust millennial periodicity. It remains unclear whether a link exists between the flood and ENSO at millennial timescales due to the lack of sufficiently long flood series. Here we test this in the Yangtze River (YR) because ENSO has the most significant impact on this drainage area. We compiled the most detailed flood ages over the middle and lower YR to reconstruct the Holocene flood record. We found that the flood variations have prominent 2,000 and 1,000‐year cycles, and they exhibit in‐phase relationship with ENSO at these cycles, suggesting a persistent modulation of ENSO on the flooding at millennial timescales in the middle and lower Yangtze basin. This study contributes to a more comprehensive understanding of the driving forces of floods in the Yangtze catchment at millennial timescales, thereby aiding to accurately assess flood hazards and flooding prediction in hydroclimatic modeling for the densely populated Yangtze basin. Key Points: We reconstructed the Holocene flood record for the middle and lower Yangtze River by compiling optically stimulated luminescence and 14C ages of flood depositsThe flood record displays clear 2,000 and 1,000‐year cyclesThe flood record is synchronous with El Niño‐Southern Oscillation at 2,000 and 1,000‐year cycles [ABSTRACT FROM AUTHOR]

The avulsion and overflow of river courses during floods, a result of channel siltation above the alluvial plain, is a cause of major natural disasters, including huge property damage and destruction of farmlands. The most sensitive to such risks is the very densely populated area of the Yellow River lower reaches, one of China's most important grain‐producing regions. Problems caused by excessive siltation are a critical issue that should be addressed with full knowledge of sediment‐generation processes, and provenance studies are essential to provide fundamental information for effective environmental management. The Sanmen Gorge is the key region where the great sediment mass produced upstream is conveyed from the middle reaches of the Yellow River to its lower reaches. This study of the terrace sequence exposed along the Sanmen Gorge combines geomorphological observations and provenance analysis based on U‐Pb zircon geochronology and heavy minerals to provide a history of sediment transport through time. The combination of previous research and the outcome of the present study demonstrate that before the Yellow River was formed as an integrated sediment‐routing system, sediments fed into the North China Plain were largely derived from local sources. Instead, after the formation of the Sanmen Gorge, huge quantities of sediment, also derived from the Qinling mountains and stored in the Fenwei basin, were flushed into the North China lowlands by the Yellow River. Such an event took place at 1.2 Ma and has since then impacted severely on floodplain landscape and eventually profoundly affected human activities in the region. Plain Language Summary: Alluvial plains with their fertile lands and plenty of water have served as the birthplace of civilization. However, the same rivers are also a cause of harm and destruction impacting agricultural civilizations during floods. The Chinese civilization originated in the lower Yellow River alluvial plain, which has long been a very important area of food production and population growth. Yellow River is one of Earth's largest rivers and has one of the highest sediment concentrations, fueled by very rapid erosion of fine‐grained sediment stored in the Chinese Loess Plateau and the Fenwei basin. After flowing rapidly through the Sanmen Gorge, the Yellow River slows down and deposits part of its huge sediment mass, causing extremely rapid accumulation in the lower reaches, where the river bed is raised well above the adjacent lowlands, thus representing a perilous threat to surrounding farmlands and urban centers. By investigating the composition and provenance of sediments of the terrace sequences exposed along the Sanmen Gorge, we can reconstruct the evolution of the Yellow River through time. Understanding river behavior and how sediment is generated and transported from the mountain region to the alluvial plain provides the knowledge necessary for more effective environmental management. Key Points: The Sanmen Gorge formed between 3.7 and 1.2 million years agoSediment provenance shows major changes after the integration of Yellow River drainageModern sediment transport is affected by reservoir construction and human activities [ABSTRACT FROM AUTHOR]

Hilltop curvature (CHT) can record erosional responses to tectonic forces and/or climate change. Although CHT has a linear relationship with the erosion rate, which is a significant advantage over traditional indicators, it is not widely used, mainly because it requires high‐resolution terrain data. Previous studies show that terrain steepness is strongly correlated with catchment‐wide erosion rates in the Qilian Shan. This relationship enables us to test the potential of CHT based on medium‐resolution terrain data (e.g., Tan DEM‐X with a resolution of ∼12 m) as an indicator of the erosion rate. We selected three typical sites in the Qilian Shan with evenly spaced ridge valleys and a continuous soil cover. At each site, we produced a high‐resolution digital surface model (DSM) using uncrewed aerial vehicles (UAVs), and then compared CHT from the UAV DSM with that from Tan DEM‐X, via LSDTopoTools. The results show that both Tan DEM‐X and the UAV DSM record similar spatial patterns of CHT, although the magnitudes vary between the three selected areas. We then examined the relationship between CHT based on Tan DEM‐X and the catchment‐wide erosion rate in the Qilian Shan. CHT has a linear relationship with the erosion rate in an area of clastic rocks, where the erosion rate is below 400 mm/Kyr. CHT extracted by Tan DEM‐X is superior to the mean basin slope in predicting the erosion rate in this clastic rock landscape. Overall, our results demonstrate the utility of Tan DEM‐X in calculating CHT to indicate the erosion rate. Plain Language Summary: Erosion occurs when Earth surface material is worn away and moved by natural forces such as wind and water. The erosion rate represents the rate at which the surface elevation decreases. Hilltop curvature extracted by terrain analysis software combined with terrain data can provide a rapid estimate of the erosion rate. However, the coverage of high‐resolution terrain data used in previous studies is very sparse. At present, the most widely terrain data with global coverage is Tan DEM‐X. In this study, we determined whether the hilltop curvature extracted based on Tan DEM‐X can predict the erosion rate. This was done by comparing the hilltop curvature extracted from Tan DEM‐X with that from high‐resolution terrain data, and then examined the linear relationship between hilltop curvature based on Tan DEM‐X and the erosion rate in the Qilian Shan in China. The trends of hilltop curvature between different areas recorded by Tan DEM‐X and high‐resolution terrain data were consistent, and the hilltop curvature based on Tan DEM‐X was linearly related to the erosion rate in an area of clastic sedimentary rocks. We suggest that Tan DEM‐X can be used to estimate the erosion rate in areas lacking high‐resolution terrain data. Key Points: We compared hilltop curvatures extracted from Tan DEM‐X and high‐resolution terrain data on different spatial scalesHilltop curvature based on Tan DEM‐X can indicate the erosion rate at the catchment scaleIn an area of clastic rocks with erosion rates below 400 mm/Kyr, hilltop curvature has a linear relationship with the erosion rate [ABSTRACT FROM AUTHOR]