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In this study, we utilize C‐band Sentinel‐1 radar images from 2015 to 2022, combined with interseismic horizontal GNSS velocities, to construct large‐scale, high‐resolution, 3‐D velocity and strain rate maps over a vast region of southern Tibet. We show the distribution of prevailing dilatational strain accumulation along the seven major rift zones. Using 2‐D elastic dislocations invoking a two‐fault model in a Bayesian framework, we quantified the decadal extension rates across the seven rift zones, and we suggest a total extension rate of 18.4 ± 1.7 mm/yr, consistent with geological and geodetic estimates. The resulting strain rate maps, combined with the earthquake catalog, help us identify areas with high earthquake potential. Our study enhances our understanding of the present‐day tectonics and kinematics in southern Tibet and provides important constraints for seismic hazard assessment in this region. Plain Language Summary In this research, we used satellite radar images from 2015 to 2022 and GNSS data to study the crustal deformation and strain distribution in southern Tibet, where the Earth's crust is actively stretching due to the collision of the Indian and Eurasian plates and the extrusion of crustal materials. By analyzing high‐resolution 3D velocities, we provided new high‐resolution surface strain maps over southern Tibet. We found that the widespread dilatational strain is mainly localized along seven major N‐S trending rift zones. Seven major rift zones are experiencing extension at a total rate of 18.4 ± 1.7 mm/yr. The strain rate maps, combined with historical earthquakes, helped us identify fault segments that are more likely to host earthquakes in the future. By mapping deformation and strain in greater detail, we provided valuable data that can improve our understanding of kinematics and earthquake risk assessments in geologically complex southern Tibet. Key Points We present InSAR‐based, high‐resolution maps of 3‐D velocities and strain rates in Southern Tibet There is prevailing dilatational strain along seven rift zones in Southern Tibet, with a total extension rate of 18.4 ± 1.7 mm/yr We show the distribution and spatial variations of extension rates for seven rift zones

Quantifying slip deficit rates on active faults in Tibet is essential for understanding fault kinematics and assessing seismic hazards, but has not been fully characterized, particularly on secondary faults. In this study, we integrate an updated interseismic Global Navigation Satellite Systems velocity field from 4,458 stations across continental China and its surroundings to calculate surface strain rates in Tibet, which we then use to invert for slip deficit rates on 263 crustal faults (383 segments). Our results reveal that ∼73% of strain rates are due to elastic strain accumulation on fault planes, and only a portion of the remaining strain rates may originate from unmodeled fault deformation. Quantitative calculations of seismic moment budgets on these fault segments indicate that they can produce earthquakes ranging from Mw 5.8 to 8.6, with 43 segments capable of generating earthquakes of Mw ≥ 7.5. Our findings provide a foundation for probabilistic seismic hazard analysis in Tibet. Plain Language Summary When assessing earthquake hazards on crustal faults, it's important to know how quickly energy is building up. In this study, we focus on the Tibetan Plateau, where the complexity of hundreds of faults makes it difficult to estimate strain accumulating using traditional models. To address this, we collected velocity data from 4,458 Global Navigation Satellite Systems stations and used those in Tibet to calculate a reliable strain rate map. We then applied a new method to invert strain rates for slip deficit rates (energy accumulation rates) on 263 active faults (383 segments) in Tibet. Our results indicate that ∼73% of the observed strain is due to slip deficit on fault planes, while the rest might be related to unmapped faults or other types of crustal deformation. We also estimated the potential magnitude of future earthquakes on these fault segments, finding that they could produce earthquakes ranging from Mw 5.8 to 8.6, with 43 segments having the potential to generate Mw 7.5+ earthquakes. Our findings help us better understand where and how large future earthquakes might be in Tibet. Key Points An updated interseismic Global Navigation Satellite Systems velocity solution comprising 4,458 sites across continental China About 73% of the surface strains are due to elastic strain accumulation on fault planes Quantifying slip deficit rates on 263 faults (383 segments) indicates they are capable of Mw 5.8–8.6 earthquakes

The 21 May 2021 Maduo earthquake was the largest event to occur on a secondary fault in the interior of the active Bayanhar block on the north-central Tibetan plateau in the last twenty years. A detailed kinematic study of the Maduo earthquake helps us to better understand the seismogenic environments of the secondary faults within the block, and its relationship with the block-bounding faults. In this study, firstly, SAR images are used to obtain the coseismic deformation fields. Secondly, we use a strain model-based method and steepest descent method (SDM) to resolve the three-dimensional displacement components and to invert the coseismic slip distribution constrained by coseismic displacement fields, respectively. The three-dimensional displacement fields reveal a dominant left-lateral strike-slip motion, local horizontal displacement variations and widely distributed near-fault subsidence/uplift deformation. We prefer a five-segment fault slip model, with well constrained fault geometry featuring different dip angles and striking, constrained by InSAR observations. The peak coseismic slip is estimated to be ~5 m near longitude 98.9°E at a depth of ~4–7 km. Overall, the distribution of the coseismic slip on the fault is highly correlated to the measured surface displacement offsets along the entire rupture. We observe the moderate shallow slip deficit and limited afterslip deformation following the Maduo earthquake, it may indicate the effects of off-fault deformation during the earthquake and stable interseismic creep on the fault. The occurrence of the Maduo earthquake on a subsidiary fault updates the importance and the traditional estimate of the seismic hazards for the Kunlun fault.

Protein- and starch-related quality traits, which are quantitatively inherited and significantly influenced by the environment, are critical determinants of the end-use quality of wheat. We constructed a high-density genetic map containing 10,739 loci (5,399 unique loci) using a set of 184 recombinant inbred lines (RILs) derived from a cross of 'Tainong 18 × Linmai 6' (TL-RILs). In this study, a quantitative trait loci (QTLs) analysis was used to examine the genetic control of grain protein content, sedimentation value, farinograph parameters, falling number and the performance of the starch pasting properties using TL-RILs grown in a field for three years. A total of 106 QTLs for 13 quality traits were detected, distributed on the 21 chromosomes. Of these, 38 and 68 QTLs for protein- and starch-related traits, respectively, were detected in three environments and their average values (AV). Twenty-six relatively high-frequency QTLs (RHF-QTLs) that were detected in more than two environments. Twelve stable QTL clusters containing at least one RHF-QTL were detected and classified into three types: detected only for protein-related traits (type I), detected only for starch-related traits (type II), and detected for both protein- and starch-related traits (type III). A total of 339 markers flanked with 11 QTL clusters (all except C6), were found to be highly homologous with 282 high confidence (HC) and 57 low confidence (LC) candidate genes based on IWGSC RefSeq v 1.0. These stable QTLs and RHF-QTLs, especially those grouped into clusters, are credible and should be given priority for QTL fine-mapping and identification of candidate genes with which to explain the molecular mechanisms of quality development and inform marker-assisted breeding in the future.

Potassium (K) input is essential for the improvement of soil fertility in agricultural systems. However, organic amendment may differ from mineral K fertilization with respect to modifying the soil K transformation among different fractions, affecting soil K availability. We conducted a 60-day lab incubation experiment to evaluate the response of soil K dynamics and availability in various fractions with a view to simulating crop residue return and chemical K fertilization in an Anthrosol of northwest China. The tested soil was divided into two main groups, no K fertilization (K0) and K fertilization (K1), each of which was subjected to four straw addition regimes: no straw addition (Control), wheat straw addition (WS), maize straw addition (MS), and both wheat straw and maize straw addition (WS+MS). Soil K levels in the available (AK) and non-exchangeable (NEK) fractions were both significantly increased after K addition, following the order of K>WS>MS. Fertilizer K was the most efficient K source, demonstrating a 72.9% efficiency in increasing soil AK, while wheat and maize straw exhibited efficiencies of 47.1% and 39.3%, respectively. Furthermore, K fertilization and wheat and maize straw addition increased the soil AK in a cumulative manner when used in combination. The mobility factor (M.sub.F) and reduced partition index (I.sub.R) of soil K were used to quantitate the comprehensive soil K mobility and stability, respectively. Positive relationships were observed between the M.sub.F and all relatively available fractions of soil K, whereas the I.sub.R value of soil K correlated negatively with both M.sub.F and all available fractions of soil K. In conclusion, straw amendment could be inferior to mineral K fertilization in improving soil K availability when they were almost equal in the net K input. Crop straw return coupled with K fertilization can be a promising strategy for improving both soil K availability and cycling in soil-plant systems.

Interferometric synthetic aperture radar (InSAR) data from 6 Envisat ASAR descending tracks; spanning the 2003–2010 period; was used to measure interseismic strain accumulation across the Northeastern Tibetan Plateau. Mean line-of-sight (LOS) ratemaps are computed by stacking atmospheric-corrected and orbital-corrected interferograms. The ratemaps from one track with different atmospheric-corrected results or two parallel; partially overlapping tracks; show a consistent pattern of left-lateral motion across the fault; which demonstrates the MERIS and ECMWF atmospheric correction works satisfactorily for small stain measurement of this region; even with a limited number of interferograms. By combining the measurements of InSAR and GPS; a fine crustal deformation velocity and strain rate field was estimated on discrete points with irregular density depending on the fault location; which revealed that the present-day slip rate on the Haiyuan fault system varies little from west to east. A change (2–3 mm/year) in line-of-sight (LOS) deformation rate across the fault is observed from the Jinqianghe segment to its eastern end. Inversion from the cross-fault InSAR profiles gave a shallow locking depth of 3–6 km on the main rupture of the 1920 earthquake. We therefore infer that the middle-lower part of the seismogenic layer on the 1920 rupture is not yet fully locked since the 1920 large earthquake. Benefit from high spatial resolution InSAR data; a low strain accumulation zone with high strain rates on its two ends was detected; which corresponds to the creeping segment; i.e., the Laohushan fault segment. Contrary to the previous knowledge of squeezing structure; an abnormal tension zone is disclosed from the direction map of principal stress; which is consistent with the recent geological study. The distribution of principal stress also showed that the expanding frontier of the northeastern plateau has crossed the Liupan Shan fault zone; even arrived at the northeast area of the Xiaoguan Shan. This result agrees with the deep seismic reflection profile.

As one of the large-scale block-bounding faults in the northeastern Tibetan Plateau, the Qilian-Haiyuan fault system accommodates a large portion of north-eastward motion of the Tibetan Plateau. In 2016 and 2022, two strong earthquakes of Mw6.0 and Mw6.6 occurred in the Menyuan area near the Lenglongling fault (LLLF) at the western segment of the Qilian-Haiyuan fault. These two adjoining events, only 40 km apart, exhibited notable differences in focal mechanisms and rupture kinematics, indicating complex fault geometries and tectonic structures in the region, which are still poorly known. Here, we obtained an interseismic velocity map spanning 2014–2020 in the Menyuan region using Sentinel-1 InSAR data to probe strain accumulation across the LLLF. We obtained the coseismic deformation fields of the two Menyuan earthquakes using InSAR data and inverted out their slip distributions. We calculated the Coulomb stress changes to examine the interactions and triggering relationship between two ruptures and to access regional seismic potential. We found that the 2016 earthquake was a buried thrust event that occurred on the northern LLLF, whilst the 2022 earthquake was a left-lateral strike-slip event that occurred on the western end of the LLLF. We indicated there may be no direct triggering relationship between two spatiotemporally adjacent earthquakes. However, the 2022 earthquake caused a remarkable stress perturbation to the surrounding area. Particularly, a large area with notable stress increase stands out along the Tuolaishan fault and the LLLF, likely posing a high seismic hazard in the region.

The Haiyuan fault zone is an important tectonic boundary and strong seismic activity belt in northeastern Tibet, but no major earthquake has occurred in the past ∼100 years, since the Haiyuan M8.5 event in 1920. The current state of strain accumulation and seismic potential along the fault zone have attracted significant attention. In this study, we obtained the interseismic deformation field along the Haiyuan fault zone using Envisat/ASAR data in the period 2003–2010, and inverted fault kinematic parameters including the long-term slip rate, locking degree and slip deficit distribution based on InSAR and GPS individually and jointly. The results show that there is near-surface creep in the Laohushan segment of about 19 km. The locking degree changes significantly along the strike with the western part reaching 17 km and the eastern part of 3–7 km. The long-term slip rate gradually decreases from west 4.7 mm/yr to east 2.0 mm/yr. As such, there is large strain accumulation along the western part of the fault and shallow creep along the Laohushan segment; while in the eastern section, the degree of strain accumulation is low, which suggests the rupture segments of the 1920 earthquake may have been not completely relocked.

Taking the 2017 Mw6.5 Jiuzhaigou earthquake as a case study, ionospheric disturbances (i.e., total electron content and TEC) and thermal infrared (TIR) anomalies were simultaneously investigated. The characteristics of the temperature of brightness blackbody (TBB), medium-wave infrared brightness (MIB), and outgoing longwave radiation (OLR) were extracted and compared with the characteristics of ionospheric TEC. We observed different relationships among the three types of TIR radiation according to seismic or aseismic conditions. A wide range of positive TEC anomalies occurred southern to the epicenter. The area to the south of the Huarong mountain fracture, which contained the maximum TEC anomaly amplitudes, overlapped one of the regions with notable TIR anomalies. We observed three stages of increasing TIR radiation, with ionospheric TEC anomalies appearing after each stage, for the first time. There was also high spatial correspondence between both TIR and TEC anomalies and the regional geological structure. Together with the time series data, these results suggest that TEC anomaly genesis might be related to increasing TIR.

The relationships between co-seismic slip and surface deformation under different rupture patterns along the Main Himalayan Thrust remain poorly understood. We established three idealized fault slip models to analyze co-seismic and post-seismic deformation, stress changes, and their impact on faults in Southern Tibetan Plateau (STP). The results show that three types of earthquakes produce distinct mountain-building deformation effects. Full-scale rupture events cause a mutual offset between co-seismic subsidence and interseismic uplift deformation in the Great Himalaya, while post-seismic vertical deformation occurs in the opposite direction to that induced by co-seismic slip. In the other two models, vertical deformation is concentrated in the Lesser Himalaya. The uplift deformation caused by blind ruptures plays a crucial role in the formation of the Kathmandu Basin. Stress perturbations on faults in STP are not influenced by rupture patterns (i.e. whether surface rupture occurs), which differs from stress transfer patterns observed in epicentral areas. The stress change pattern in STP effectively explains the distribution characteristics of co- and post-seismic Coulomb stress changes induced by the 2015 Gorkha earthquake. Among them, stress changes in the east–west direction play a driving role in the rupture of nearly north–south striking rifts.