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Based on dust storm records and meteorological data from six stations in the area surrounding the Tengger Desert over the period 1960-2007, the diurnal, monthly and interannual variation of dust storms and severe dust storms, as well as their relation to wind speed, precipitation and temperature, are analyzed and discussed. Statistical analyses demonstrate that such storms occur more frequently from 9:00 to 21:00 local standard time and much more frequently between March and May, especially April. Dust storm frequency (DSF) and severe dust storm frequency (SDSF) show a significant linear decreasing trend from 1960 to 2007. For monthly variability, winds (especially strong ones with speeds 10-20 m/s) are the main factor controlling both dust storm types. Precipitation and temperature have an indirect effect on DSF and SDSF by controlling vegetation growth. For interannual variability, strong wind is still the main control, with precipitation a relatively important cofactor. Temperature has an irregular but somewhat negative relationship with dust storms. Precipitation and especially temperature have likely been important in the increase of DSF since 2000. [ABSTRACT FROM AUTHOR]

Temperate glaciers are more sensitive to climate change than are polar or continental glaciers, and can drive remarkable runoff variation in local water catchments. Changes in the glacier area and surface elevation of the three monsoonal temperate glaciers in the Gongga Mountains, China, were analyzed using series of remote sensing images and digital elevation model (DEM) data. All possible sources of uncertainty were considered in detail. The results showed that the total glacier area decreased by 4.3 km 2 (6.7%) between 1966 and 2010. A comparison of glacier surface elevations using DEMs derived from dual-frequency differential GPS (DGPS) surveys in 2010, and from 1966 to 1989 from topographic maps. The three glaciers underwent significant mass loss from 1966 to 2010 and the mean surface elevation changes were −0.90 ± 0.45 m/y, −1.06 ± 0.45 m/y, and −1.12 ± 0.45 m/y for Hailuogou (HLG), Dagongba (DGB) and Yanzigou (YZG) Glaciers, respectively, from 1966 to 2010. Analysis of the meteorological data showed that the mean annual air temperature increase was the main reason for the thinning and volume loss. Thinning of the glacier tongue and volume loss was more intense in the period 1989–2010 than in 1966–89. Debris thickness and other factors are also believed to play important roles in differential thinning among different areas and periods. [ABSTRACT FROM AUTHOR]

We investigate the changes at nine glaciers in the Ningchan and Shuiguan river source, eastern Qilian Mountains, between 1972 and 2010. According to analysis of topographic maps and multispectral satellite data, all nine glaciers in the study area have retreated, by a maximum of 250±57.4m and a minimum of 91±57.4m. The total glacier area decreased by 1.20km2, corresponding to 9.9% of the glacierized area in 1972. Comparing the two DEMs generated from the topographic maps and Real-Time Kinematic GPS data, the mean glacier thinning rate was 0.64myr−1 between 1972 and 2010. The most significant thinning generally occurred on the termini. The ice-volume loss was about 106.8±46.7×10−3 km3 (equal to 90.8±39.7×10−3 km3 w.e.), which suggested a mean water discharge of 0.1±0.05m3/s during 1972–2010. Based on analysis of meteorological data, the summer temperature (June–August) tends to increase over a similar time period. The consistency of temperature increase and glacier shrinkage allows us to suggest that air temperature plays an important role in glacier changes in this region. [ABSTRACT FROM AUTHOR]

Abstract: The way in which the NE Tibetan Plateau uplifted and its impact on climatic change are crucial to understanding the evolution of the Tibetan Plateau and the development of the present geomorphology and climate of Central and East Asia. This paper is not a comprehensive review of current thinking but instead synthesises our past decades of work together with a number of new findings. The dating of Late Cenozoic basin sediments and the tectonic geomorphology of the NE Tibetan Plateau demonstrates that the rapid persistent rise of this plateau began ~8±1Ma followed by stepwise accelerated rise at ~3.6Ma, 2.6Ma, 1.8–1.7Ma, 1.2–0.6Ma and 0.15Ma. The Yellow River basin developed at ~1.7Ma and evolved to its present pattern through stepwise backward-expansion toward its source area in response to the stepwise uplift of the plateau. High-resolution multi-climatic proxy records from the basins and terrace sediments indicate a persistent stepwise accelerated enhancement of the East Asian winter monsoon and drying of the Asian interior coupled with the episodic tectonic uplift since ~8Ma and later also with the global cooling since ~3.2Ma, suggesting a major role for tectonic forcing of the cooling. [Copyright &y& Elsevier]

Abstract: A total of 41 spore species and 63 pollen taxa, including seven angiosperms, were identified from 24 samples of the Early Cretaceous succession (latest Barremian to Aptian) at the Wulan Section in the east part of the Yingen-Ejinaqi Basin, Inner Mongolia, China. In a stratigraphically upward order, three types of palynomorph assemblages were identified. Palynological assemblage I (PA I) was dominated by bisaccate pollen, whereas palynological assemblages II (PA II) and III (PA III) were characterised by abundant Classpollis associated with more spores. PA III contained the highest spore content. Angiosperm pollen display an increasing trend in diversity and abundance from PA I to PA III. PA I is most likely correlated to the Chinese Cretaceous palynofloral Transitional Zone and northern Disacciatrileti – Cicatricosisporites Province, whereas the assemblages II and III represent the transitional zone. The composition of these assemblages suggests that the climate was cool and humid within the basin during the latest Barremian, subsequently warmer and drier during the Early Aptian and, finally, became slightly wetter and warmer during the Late Aptian. Early angiosperm pollen occur frequently in this section, including that of Clavatipollenites, Asteropollis and Songipollis. On the stratigraphical order, these angiosperm pollen show a clear and continuous increase regarding the relative abundance and diversity of angiosperm, which most likely reflects the incipient dispersion of angiosperm plants during the latest Barremian to Late Aptian in inner East Asia. Lastly, a comprehensive compilation of published literature indicates that the emergence and evolution of early Asteropollis was not simultaneously worldwide, most likely occurring earlier in Eurasia than in other regions with a dramatic increase in both diversity and abundance prior to the emergence of tricolpate pollen. [Copyright &y& Elsevier]

The grain size of the loess-like sediment in the Jinsha River Valley is essentially similar to that of typical loess, and it differs from that of the fluvial sediment in the Jinsha River area. We conclude that the loess-like sediment is of aeolian origin, as is the loess of the Chinese Loess Plateau. The geochemical characteristics of the loess-like sediment are similar to those of dammed lake and fluvial sediments in the same area, which is significantly different from those of the typical loess in NW China. The geochemical characteristics show that the loess-like sediment originated from proximal materials. Combined with the grain-size distribution pattern of the aeolian deposits, we suggest that the loess-like sediment of the Jinsha River Valley originated from the dammed lake and fluvial sediments that accumulated in the valley. The local mountain-valley wind circulation (especially the valley wind in winter and spring) provided the transport force for the loess-like sediment. The presentation of the loess-like sediment may indicate the appearance of the grassland and forest steppe and the beginning of the dry-hot valley phenomenon. [ABSTRACT FROM AUTHOR]

The Shagou section contains rich information about the formation and evolution of sand storms in the windward side of of the Tengger Desert (southern Tengger Desert, east of the Hexi Corridor). By investigating the grain size classes and the standard deviation of three sample groups in the Shagou section we discover that every group has four sensitive grain size components, and each sensitive grain size component has a tendency to be finest for the palaeosol stratum, coarsest for the sand stratum, and the loess intermediate between the two. The three sample groups have differences in their grain size distributions. Both S1 (average) and L1 (average) have two peaks. L1 (sand stratum) has three peaks and an additional coarse peak (275.4-550 µm) which is consistent with the grain size distribution pattern of the modern sand storm samples in the Tengger Desert. Moreover the additional peak of the palaeo-sand stratum correspondingly the interval of the grain size is exactly consistent with one of the four sensitive grain size components. Because the sand stratum in L1 of the Shagou section was the direct result of sand storm process of the Tengger Desert, the sand group percent of 275.4-550 µm in the Shagou section could be used as a sensitive indicator of sand storm in the south of the Tengger Desert (east of Hexi Corridor). [ABSTRACT FROM AUTHOR]

Seven terraces along the Weihe River in Longxi basin have been investigated. These terraces all consist of archetypal duality in structure, namely the floodplain deposits and the layer of gravels overlaid by varying thickness of the bess. By resorting to various dating approaches such as palaeomagnetic, optically stimulated luminescenece (OSL), 14C and loess-paleosol sequence, we provide preliminary timing of these seven terraces along upper Weihe River. Analysis on sedimentation characteristics and dating of these terraces showed that seven terraces may be jointly generated by tectonic uplifts and climatic changes. Tectonic uplifts may accommodate initial river incision, and climatic change may be responsible for processes of subsequent channel widening and aggradation. Aggradation normally occurs during glacial periods, in contrast to down-cuttings during transitions from glacial to interglacial period. Moreover, on the basis of the timings and heights of these terraces, we infer that the long-term rate of river incision was determined to be 0. 2 m/kyr during the last 870 kyr, which differs from other river incision rates. This discrepancy may reflect spatio-temporal differentiation of tectonic activities in the Qinling orogenic belt during the Pleistocene. [ABSTRACT FROM AUTHOR]

Analysis of morphological properties in the San men Gorges region of the Yellow River shows that four river terraces have been developed at the entrance to the gorges. Commonly, thick aeolian loess-paleosol sequence was deposited on the terraces, which makes it easy to date the terraces. The dating of paleomagnetic, loess-paleosol sequence matching and thermoluminescence show that terraces T2, T3 and T4 were formed 0.129 Ma, 0.625 Ma and 0.865 Ma ago, respectively. The formation of these terraces in this region indicates that the Yellow River has experienced four intensive downcutting events during the last 0.9 Ma. The Yellow River cut through the Sanmen Gorges and inpoured into the East China Sea no later than 0.865 Ma. [ABSTRACT FROM AUTHOR]

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]

Provides information on a study of palaeokarst and planation surfaces on Tibet Plateau. Information on the distribution and levels of the planation surfaces on the plateau; Detailed information on properties and initial elevations of the planation surfaces.

Based on field investigations, laboratory analyses and C dating, this paper discusses the laws of the formation and development of the paleosols in the northeast region of the Qinghai-Xizang Plateau since Late Pleistocene. The authors reconstruct basic conditions of climate, vegetation, soil and natural zones during the three periods in which the paleosols were formed, i.e. the last interglacial of the Late Pleistocene, warm stage of Late Glacial and the Optimum of Holocene. Finally, this paper discusses the relationship between the paleosols and the uplift of the Qinghai-Xizang Plateau. [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]

• Calculated the glacier mass change using multi-temporal DEMs and degree-day model. • The mean rate of change in glacier surface elevation was −0.43 ± 0.18 m/a from 1972 to 2016. • Glacier coverage in the JTLB accounted for only 1.4% of its surface area, but 4.6% of its river runoff. Glacial meltwater-fed streamflow from the Qilian Mountains provides a much-needed source of water for the northeastern margins of the Tibetan Plateau (TP) and surrounding regions. We analyzed changes in glaciers located in the Lenglongling Mountains (LLM) in the eastern Qilian Mountains in terms of glacier area and surface elevation. These analyses were accomplished using multi-temporal satellite images and studying digital elevation models (DEMs) based on topographic maps and ZY-3 data. The results showed that from 1972 to 2016, glacier coverage decreased by 41.1 km2, leaving only 62.1 km2 extant in 2016. The mean rate of change in glacier surface elevation asl was −18.7 ± 1.2 m (−0.43 ± 0.03 m a−1) over the same period. In situ measured data from Ningchan No.1 Glacier (NC01), combined with meteorological records, were also employed to develop a spatially distributed degree-day model for the LLM glaciers. These two approaches yielded similar results, allowing the reconstruction of a consistent time series that detailed annual changes in glacier mass over the past 44 years. In addition, we calculated that the mean annual glacial meltwater-fed streamflow from 1972 to 2013 in the Jiutiaoling Basin (JTLB) northeast of the LLM was equivalent to 1.4 × 107 m3, or 4.6% of the area's total annual streamflow. It is remarkable that, in years when streamflow was relatively lower, such as 1972, 1991 and 2013, glacial meltwater accounted for a higher proportion (more than 8%) of the streamflow. [ABSTRACT FROM AUTHOR]

Despite decades of study, the factors that controlled the formation and evolution of the upper reaches of the Yellow River, including uplift of the northeastern Tibetan Plateau, Pliocene-Pleistocene climate change, and autogenetic processes are still poorly constrained. The stratigraphic record of such paleogeographic evolution is recorded in the sequence of nine terraces formed during progressive incision of the Yellow River in the last 1.7 Ma. This article investigates in detail for sediment provenance in terraces of the Lanzhou area, based on heavy-mineral and geochemical (REE) signatures. Two main provenance changes are identified, pointing each to a major paleogeographic reorganization coupled with expansion of the upper Yellow River catchment and enhanced sediment fluxes. The first change took place between the deposition of terrace T9 (formed around 1.7 Ma) and terrace T8 (formed around 1.5 Ma), when rapid fluvial incision point to tectonic control and active uplift of northeastern Tibetan Plateau. The second change took place between deposition of terrace T4 (formed around 0.86 Ma) and terrace T3 (formed around 0.14 Ma), during a period of low incision rates and notably enhanced sediment fluxes as a response to enhanced East Asian Summer Monsoon and consequently increased precipitations, pointing instead chiefly to climatic control. [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]

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 flood lasted for ~ 10 h, with a peak discharge of 105 m3/s, leading to average erosion of 10 m, and contributed ~ 1–2 × 103 times more sediment than over long-term mean fluvial processes. The flood produced extensive lateral erosion, which triggered a threefold widening of the valley floor and abundant subsequent landslides. The ubiquitous boulder bars deposited in the channel inhibited incision, and facilitated lateral erosion after the flood. The resulting channel configuration and extensive bank erosion continue to affect fluvial dynamics until the next catastrophic flood that remobilizes the boulders. Our quantitative findings highlight the profound importance of recurrent outburst floods for gorge development and landscape evolution in Eastern Himalaya. [ABSTRACT FROM AUTHOR]

Knowledge of the composition of modern fluvial sediments is important for understanding the combined effect of lithology and climatic factors on the erosion and sedimentation within drainage basins, However, this information is incomplete in arid and semiarid environments. In this study, 37 modern fluvial sediment samples were collected from the Heihe River and its major tributaries, in the NE Tibetan Plateau, and for analyses of heavy minerals, trace and rare earth elements (REEs) and grain size. The main aim was to explore the influence of erosion, transport and deposition processes on sediment composition, and to define appropriate provenance indicators specific to these rivers. Along the Heihe River, the amount of unstable minerals is abundant and not changing, these result suggests that chemical weathering plays only a minor role. The composition of six sediment samples obtained from the upper-middle reaches of Heihe River are influenced by hydrodynamic sorting processes, which resulted in enrichment of heavy minerals. In addition, the mineralogical and geochemical compositions lead to different conclusions regarding the contributions from tributaries to the sediments in the middle-lower reaches of the Heihe River. This may reflect the occurrence of contrasting hydrodynamic conditions in Heihe River and its tributaries which result in the transport of different size fractions. Moreover, the <63 μm fraction of the sediments from the Heihe River basin has been affected by inputs of eolian dust, which means that this fraction is less influenced by the rock types within the sediment source areas than is the case for the other size fractions. Therefore, we conclude that the sand fraction is more suitable for source to sink analysis of fluvial sediments within this and comparable environments. In the upper areas of the Fengle River basin, the combination of low temperature, sparse vegetation coverage and high precipitation have resulted in intense erosion. This case reminds us to note the effect of the climatic zonation on the provenance analysis in arid regions. [ABSTRACT FROM AUTHOR]

Abstract The kinematics of thrust fault is key to understand the deformation and uplift of mountain ranges. Along the northern front of the central Qilian Shan mountain range, the NE Tibet Plateau, a flight of terraces developed along the Red Sand River were deformed above a growing fault-propagation fold. Via luminescence and 10Be exposure dating, abandonment ages of the terrace surfaces were determined to be 100.9 ± 5.8 ka BP for T9, 88.7 ± 7.0 ka BP for T8, and 68.8 ± 7.6 ka BP for T7. Terrace profiles measured by differential GPS across the monocline were used to constrain the recent fold deformation, and the trishear model was applied to estimate the fault slip rate and thrust history. We thus derived an average slip rate of 1.3 ± 0.1 mm/a for the Heihekou (HHK) fault since ~90 ka BP. In addition, our results imply that the onset of the HHK fault occurred at 0.8–1.4 Ma, indicating a recent northeastward propagation of the active thrust faulting of the North Qilian Shan Fault (NQF). Our results also indicate uniformly distributed slip along the western, central, and eastern segments of the north Qilian Shan. Due to the different thrust kinematics along the NQF, the uplift rate is not uniformly distributed along the hanging wall of the thrust. Highlights • 10Be dating of folded terraces yielded a fault slip rate of 1.3 ± 0.1 mm/a on the central segment of the NQF since 90 ka. • The onset age for the HHK fault is determined as 1.4–0.8 Ma, indicating the recent northward propagation of the NQF. • The slip along the NQF thrust system is uniformly distributed along the north Qilian Shan. [ABSTRACT FROM AUTHOR]

Research into the surface soil pollen found within different sediments constitutes one important part of modern palynological analysis; however, such studies have not been carried out in the arid regions of Asia. In order to determine the main characteristics of the pollen assemblages of different sediments, 26 surface pollen samples were selected from five different sedimentary environments (sand dune, alluvial fan, wetland, floodplain and riverbed) found in three transverse sections in the middle reaches of the Heihe River. The results show that the five different sediment types have significantly different pollen assemblages: (1) sand dune: Chenopodiaceae - Artemisia - Nitraria - Poaceae; (2) alluvial fan: Nitraria - Chenopodiaceae; (3) wetland: Poaceae - Typhaceae - Chenopodiaceae – Artemisia ; (4) floodplain: Picea - Cyperaceae - Chenopodiaceae - Artemisia - Asteraceae; and (5) riverbed: Picea - Cyperaceae - Polypodiaceae - Chenopodiaceae – Artemisia . The auxiliary functions derived from analyses of the principal components also indicates a significant difference between pollen assemblages for the five different sediment types. This established the veracity of these particular pollen assemblages representing these five different sedimentary environments, thereby improving the reliability of our research results. Those results provide the fundamental information required for any reconstruction of the region's paleovegetation and paleoclimate based on the pollen records found in different sedimentary environments. [ABSTRACT FROM AUTHOR]

Knowledge of erosion rates through time is of great importance to understand the effects of tectonics and climate on the topographic evolution of mountain belts. In this study, we present a 10Be-based paleo-erosion record for the northern Qilian Shan (NE Tibet) during the last 4.2 Ma. This new record is based on samples from a magnetostratigraphically dated drillcore from the foreland of the northern Qilian Shan (i.e., the Hexi Corridor). The 10Be-based paleo-erosion rates obtained from the drillcore lie between ~40 and ~150 m/Ma, with the exception of two transient peaks at ~3.4 Ma (~330 m/Ma) and ~2.0 Ma (~220 m/Ma). These high values may result from transitions to a generally cooler climate with more pronounced changes between glacial and interglacial periods. Apart from these peak values, erosion rates during the period from 4.2 to 2.8 Ma are rather low (~40 to ~70 m/Ma; mean: 50 m/Ma), whereas erosion rates over the last ~1.5 Ma are higher, ranging from ~80 to ~150 m/Ma (mean: ~112 m/Ma). We attribute the slower erosion between 4.2 and 2.8 Ma to a warmer climate, with more rainfall than today, and a lower relief in the sediment-source region. These factors led to a stabilization of hillslopes and caused erosion rates to be low. Subsequently, progressive cooling, aridification, and enhanced glacial and periglacial processes reduced the vegetation cover and increased hillslope erosion. In addition, ongoing rock uplift and concomitant river incision in the Qilian Shan may have increased the local relief. These factors explain the higher erosion rates in the past ~1.5 Ma. Available evidence on tectonic boundary conditions, drainage evolution, sedimentary environment, and paleo-climate conditions suggest that the geomorphology of the northern Qilian Shan has not significantly changed over that period. • We derive a 10Be-based paleo-erosion record for the Qilian Shan over the past 4.2 Ma. • Gradual cooling and glacial processes have increased hillslope erosion after 2.8 Ma. • Low erosion rates in the Pliocene were due to a warmer climate and a lower relief. [ABSTRACT FROM AUTHOR]

The detailed evolution of valley-damming by glaciers on the southeastern Tibetan Plateau, including the large Gega paleolake, is reconstructed based on observed sediment sequences, and optically stimulated luminescence (OSL) dating. In total, six main lithofacies associations are inferred that represent three relevant sedimentary environments associated with the paleolakes, i.e. lacustrine, deltaic and fluvial. Since the local last glacial maximum (LGM), there have been at least three river-blocking episodes and consequent phases of lacustrine development in the Gega and Jiedexiu dammed lakes. They occurred at ca. 25–17 ka, 14–11 ka, and ∼4 ka. Sedimentological evidence shows that the glacier-dammed lakes were not stable; they experienced oscillations of lake level through short-time drainage events. The damming events and subsequent outburst floods were likely triggered by changes in the extent and thickness of glaciers, caused by rapid climatic changes. This seems to be consistent with proglacial lakes occurring elsewhere, although the dynamics of glacier-dammed lakes can be highly variable between catchments and through time due to the influence of climate-dependent factors on the proglacial lakes. • Evolution of valley-damming by glaciers on the southeastern Tibetan Plateau is reconstructed. • Six lithofacies associations are inferred that represent three relevant sedimentary environments. • Damming events and subsequent outburst floods were likely triggered by changes in the extent and thickness of glaciers. • Sedimentological evidence shows that the glacier-dammed lakes were not stable but experienced short-time drainage events. [ABSTRACT FROM AUTHOR]

Understanding the processes of fluvial geomorphic evolution is based on thorough evaluation of how rivers respond to tectonic activity and climatic change, with river terraces representing a key archive of alternating deposition and incision in response to such forcing, enabling an excellent means for correlation with tectonic and climatic records. An example presented here points to a difference in fluvial response to climate fluctuations along a trunk river and its tributary: the Yellow River and its tributary the Xike River, which has incised the Lajia Gorge to pirate the Zoige Basin, in the eastern Tibetan Plateau. Based on Accelerator Mass Spectrometry 14C dating, the chronological sequence of basin fill top and fluvial terraces below has been established, defining the drainage reorganization of the Yellow River excavation through the Zoige Basin since the Last Glacial Maximum. Spatial and stratigraphic comparison between the two fluvial sequences, combined with correlation with high-resolution climatic records, indicates that the tributary Xike River formed more terraces in response to trunk incision (base-level variation), climatic fluctuations, and underlying weak bedrock than the Yellow River. Thus, our results not only demonstrate a combined archive of climatic fluctuation and tectonic uplift recorded in the fluvial terrace sequences, but also suggest that the generation of fluvial terraces may be influenced by the underlying bedrock within the same tectonic and climatic settings. • The Yellow River excavating through the Zoige Basin is constrained before 19 ka. • Fast uplift drives a sensitive fluvial response to sub-orbital climatic cycles. • Drainage scale affects the sensitivity of fluvial response to climate change. • Fluvial terrace is archive of the coupling between uplift and climate change. [ABSTRACT FROM AUTHOR]

ESR (electron spin resonance) spectra of quartz samples irradiated with varying gamma (γ) dose were measured at different microwave power levels (0–200 mW). The microwave power saturation characteristics of Al and E ′ centers were systematically investigated, and the mechanisms by which the power saturation characteristics affected equivalent dose (D e) fitting results in ESR dating were revealed. The experimental results demonstrated that irradiation reduces the spin-lattice relaxation time, resulting in the inability to intrinsically characterize the number of spins in a series of aliquots when the ESR intensity exhibits significant saturation. The simulation results indicated that changes in spin-lattice relaxation characteristics can cause distortion in the dose response curve (DRC) at high power levels, leading to deviations in D e values. A method that uses the slope of the approximate linear regime of the power saturation curve (PSC) as an intrinsic metric of ESR intensity is proposed; this method has been preliminarily validated in both experiments and simulations. • ESR intensity varies with the number of spins, microwave power, and relaxation time. • Equivalent dose depends on ESR's intrinsic representation of the number of spins. • Irradiation alters relaxation, deviating ESR intensity's characterization of the number of spins. • Equivalent dose measured within the linear regime of the power saturation curve is intrinsic. [ABSTRACT FROM AUTHOR]

• A cross-disciplinary method quantifies river biogeomorphic succession phases at the reach scale. • A trial application shows that Biogeomorphic landform ratios effectively differentiate phases of river evolution. • The approach is generic and can be used in different situations. The Fluvial Biogeomorphic Succession phase model (FBS model) differentiates Geomorphic (G), Pioneer (P), Biogeomorphic (B) and Ecological (E) phases of hydro-geophysical-biological interactions in river systems. To date, quantitative applications of this model have been restricted to field surveys of vegetation composition analysis at the patch-scale. Here we develop a biogeomorphic landform mapping approach to determine the dominant biogeomorphic succession phase at the reach scale. We categorize river morphology into four biogeomorphic landform types (G-, P-, B- and E-landforms) that have particular geomorphic, substrate and vegetation cover characteristics. Ratios of these landforms are used to calculate the dominant succession phase in a given reach. A test of this method conducted for two contrasting anabranching reaches of the Upper Yellow River indicates that landform ratios provide an efficient and reliable approach to assess river biogeomorphic succession phase. The approach can be adapted to support systematic cross-scalar analyses across the range of river environments. [ABSTRACT FROM AUTHOR]