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On Sep. 5, 2022, an MS 6.8 earthquake struck Luding County. The earthquake triggered large amounts of co-seismic landslides, which blocked the Wandong River for nearly 24 hours. Field surveys, image interpretation, spatial statistics, and hydro-logical calculations were used to investigate the characteristics of co-seismic landslides and the risk of debris flow following the earthquake. According to the findings, co-seismic landslides are primarily found in areas of earthquake intensity IX, and their sizes are typically small and medium. They are distributed along both sides of the channel, particularly on both sides of the thin ridge facing the air. The distance from the fault and slope controls the distribution of co-seismic landslides. The volume of debris flow runout in the Wandong catchment may be twice that of the debris flow prior to the earthquake. On this basis, the following disaster prevention and mitigation suggestions were put forward. The risk of runout debris flow in the catchment should be strengthened; The value of triggering rainfall of debris flow should be obtained as soon as possible through comprehensive monitoring and early warning; The scale amplification factor of debris flow should be fully considered in the design of debris flow prevention and control projects. This research can be used as a scientific reference for disaster prevention and mitigation of post-earthquake debris flows.

Multi-period debris flows have been developed in the last glacial period of the late Pleistocene-Holocene near the Grand Bend of the Yarlung Zangbo River in southeast Tibet, which combined to form a modern large-scale fan-shaped accumulation. The debris flows in the Bangga gully, Pai Town, were explored by ground survey, borehole, and 14C dating methods to investigate the chronological sequence of formation, accumulation depth, and outrush range. The analysis results show that there are still small-scale debris flows in the tributaries of the Bengga gully, and they are widely accumulated in the channel, but no debris flow accumulation has been found in the existing accumulation fan area. The Holocene debris flows in the Bunga gully were active around 8500 years ago, and the cumulative accumulation depth of a single period is about 10.9 m. The two carbon samples in the light gray silt sand formed by the shallow lake facies (fluvial facies) show that the modern riverbed of the Yarlung Zangbo River was deposited at a depth of about 0.4 m in 40 to 100 years, and the annual average deposition rate was about 4~10 mm. The boreholes at 2906.1~2896.7 m and 2849.4~2848.2 m above sea level reveal a thickness of 9.4 m and 1.2 m cake-like bluish-gray clay in turn. It is assumed that two river-blocking events occurred. The above results could provide a reference for the study of the debris flow activity characteristics since the Holocene in this region.

On September 5th, 2022, the Ms 6.8 earthquake in Luding County, Sichuan Province induced large numbers of geological hazards. In order to deeply understand the evolution, distribution, and characteristics of geological hazards caused by the earthquake, we obtained the distribution of geological hazards by the field investigation and remote sensing interpretation. The conditions for hazard control and the countermeasures for hazard prevention and reduction are also analyzed. The results show that as of 22:00 on September 14, 2022, the earthquake has induced 565 geological hazards with threat objects in Luding County and Shimian County (including 331 collapses and 234 landslides), and 81 existing geological hazards whose deformation increased. The geological hazards induced by the earthquake are mainly medium and small mass high-level collapses, which are mainly concentrated in the areas with Seismic intensity zone of Ⅸ near the epicenter. These areas include Moxi Town, Detuo Township, both banks of Dadu River between Detuo Township and Dewei town in Luding County, Caoke Township and Wanggangping Township in Shimian County. According to the experience of the Wenchuan earthquake, the debris flow will be active in the next five years, and its characteristics of high frequency and viscous debris flow should be considered in the design of debris flow prevention and control engineering. Under the rainfall condition, the landslide deposition remaining on the slopes of Dadu River banks in the section of Detuo Township—Dewei Town can easily transform into debris flow. The transformation forms of the two hazards’ types should be fully considered in the design of prevention and control projects. The study can provide a reference for earthquake geological hazard prevention and post hazard reconstruction planning in the earthquake area.

The detection of concealed water-conducting structures is essential for preventing water inrush disasters. Aiming to mitigate the limitations inherent in using any single technique, a comprehensive approach that combines integrated mining geophysical exploration, hydrogeological drilling, and hydrochemical exploration (GDH) is proposed for the exploration of concealed water-conducting structures. By conducting a thorough analysis of the background geological data obtained through surface exploration, potentially concealed water-conducting structures can be predicted. Then, a combination of the seismic reflection method (SRM) and mine transient electromagnetic method (MTEM) can be used to detect the location and water-bearing properties of the target structures. Afterwards, the target drilling areas are defined by the anomalies detected by the integrated mine geophysical technique, and the drilling method can directly acquire the hydrogeological information of water-conducting structures and verify the results of the geophysical methods. By means of hydrochemical analysis, inrush water sources and their runoff conditions can be identified, and the spatial relationship betweenof the source aquifers and mining space can be determined; hence, the properties, scale, and configuration of the water-conducting structures can finally be evaluated. Employing a water-conducting fault in a mine as a case study, we verified that the integrated method overcomes the limitations and possible biases of each method, providing a multiple-method solution that can accurately detect concealed water-conducting structures to help prevent water inrush disasters. [ABSTRACT FROM AUTHOR]

Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) is a serious invasive pest in China. In this study, we determined whether exogenous jasmonic acid (JA) and ethylene (ET) treatments could induce resistance against F. occidentalis in faba bean plants. First, we investigated the effects of different concentrations of JA or ET alone on F. occidentalis and then assessed the effects of optimal concentrations of JA and ET combined. Our results showed that the optimal concertation of JA was 2 mmol/L and ET was 0.5 mmol/L. JA + ET mixture showed the greatest inhibitory effect in terms of oviposition and feeding. JA with ET was found to induce changes in the activities of lipoxygenase (LOX), allene oxide synthase (AOS), polyphenol oxidase (PPO), 1-aminocyclopropane 1-carboxylic acid synthase (ACS), and trypsin inhibitor (TI). This treatment also activated or inhibited the relative expression levels of LOX1, ACO2, ACS2, and AP2/ERF. Treatment of faba bean plants with JA and ET significantly prolonged F. occidentalis development and adult preoviposition period, significantly reduced per-female oviposition, and altered male longevity and offspring demographic parameters. These results indicate that JA with ET can induce defenses against the growth and development of F. occidentalis in faba bean plants.

Understanding the failure process in frozen porous rock is of great importance to both geomorphology research and engineering design in cold regions. The mechanical behavior of frozen porous rock has its own particularity due to the existence of ice and unfrozen water in pores. To investigate the failure process in frozen rocks, uniaxial compression tests on oven-dried, air-dried, and water-saturated sandstones at 15°C and −20°C were conducted, and the electrical resistances of rock samples were monitored during compression, with which the pressure-melting effect of pore ice can be interpreted. Moreover, the phase composition of pores in sandstone before and after freezing was measured through the nuclear magnetic resonance (NMR) method. The results show that the initial water content of frozen rock changes the variation trend of electrical resistance, that is, the starting point of increasing stage in electrical resistance is shifted from the microcrack propagation stage in frozen oven-dried and air-dried samples to the stress peak in the frozen water-saturated sample. Also, the electrical resistance of frozen water-saturated rock decreases by 29.4% in the microcrack compaction stage, which is 7.4 times higher than that of frozen oven-dried rock and 4.3 times higher than that of frozen air-dried rock. Finally, 96% of pore water (free water, capillary water, and amounts of adsorbed water) is frozen in the saturated rock. The freezing point of water in microcracks is severely depressed by the strong capillary pressure, while the stress concentration effect in microcracks enlarges the applied pressure greatly and eventually induces pressure melting of pore ice. Based on the results and analysis, we suggest that the pressure-melting effect works primarily in the microcrack compaction stage and microcrack propagation stage and remolds the failure process of frozen saturated sandstone by altering the interaction between ice and pore (or microcrack). [ABSTRACT FROM AUTHOR]

On Sep. 5, 2022, an Ms6.8 earthquake struck Luding County. The earthquake triggered large amounts of co-seismic landslides, which blocked the Wandong River for nearly 24 hours. Field surveys, image interpretation, spatial statistics, and hydro-logical calculations were used to investigate the characteristics of coseismic landslides and the risk of debris flow following the earthquake. According to the findings, co-seismic landslides are primarily found in areas of earthquake intensity IX, and their sizes are typically small and medium. They are distributed along both sides of the channel, particularly on both sides of the thin ridge facing the air. The distance from the fault and slope controls the distribution of co-seismic landslides. The volume of debris flow runout in the Wandong catchment may be twice that of the debris flow prior to the earthquake. On this basis, the following disaster prevention and mitigation suggestions were put forward. The risk of runout debris flow in the catchment should be strengthened; The value of triggering rainfall of debris flow should be obtained as soon as possible through comprehensive monitoring and early warning; The scale amplification factor of debris flow should be fully considered in the design of debris flow prevention and control projects. This research can be used as a scientific reference for disaster prevention and mitigation of post-earthquake debris flows. [ABSTRACT FROM AUTHOR]

• Tree rings have recently become a widely used tool in landslide studies. • We explore the potential of trees in providing a new ecosystem service of landslide monitoring. • We present results obtained for 48 Nepalese alders sampled on a landslide in the Moxi basin, Sichuan, China. • Dendrochronology can provide data for landslide hazard assessment, monitoring and prediction. Landslides are destructive geomorphological processes that cause economic and social losses. This stimulates the development of new tools related to landslide hazard. Recently, trees, their growth rings and dendrochronology have become widely used in landslide studies. Thus, this study aims to explore the potential of trees in providing landslide-monitoring ecosystem services through dendrochronology. In our opinion, establishing such an idea would help promote empirical evidence on the efficiency of tree-ring-based tools to decision-makers. We use the example of a landslide in the Moxi basin, Sichuan, China and present results of dendrochronological analysis of growth eccentricity in 48 Nepalese alder (Alnus nepalensis) trees. This analysis provided data on event timing and magnitudes, average frequency and recurrence interval for reactivation of the study landslide, as well as spatial variability of landslide active. Based on dendrochronological data we were also able to determine the current slope balance and general hazard of landslide reactivation on the study slope. Our study shows that trees and dendrochronology can provide data on the activity of landslides that can complement and improve the results of standard engineering methods. Moreover, dendrochronology itself can provide the full information needed for landslide hazard assessment, monitoring and prediction. [ABSTRACT FROM AUTHOR]

Owing to kinetic‐sluggish nature of electrocatalytic oxygen transformation processes, it is pivotal to develop durable and efficient bifunctional air electrode catalysts for fabricating high‐performance Zn–air batteries (ZABs). In this work, oxygen vacancy (Ov) induced Mn(III) sites optimization is achieved via nano‐micro structure modulation. Protonated carbon nitride (p‐C3N4) is applied as a structure‐stiffening module to immobilize α‐MnO2 on N/P‐doped active carbon (NPAC) and induce Ov construction. X‐ray adsorption spectra (XAS) disclose the formation of Ov and Mn(III) sites in MCC, the unit coordination structure is well maintained with the aid of a dual‐carbon strategy. Mn(III) sites efficiently catalyze oxygen reduction/evolution reaction (ORR/OER), MCC shows high half‐wave potential (E1/2) of 0.88 V for ORR and low potential at 10 mA cm−2 (Ej = 10) of 1.64 V for OER. According to density functional theory (DFT) simulations analysis, the gorgeous bifunctional activity is owing to that optimized charge distribution facilitates the intermediates transformation. Aqueous ZABs based on MCC manifests high peak power density of 452 mW cm−2 and durable cycling stability of 1640 h. Quasi‐solid‐state ZABs based on MCC also show satisfactory performances (175 mW cm−2, 105 h). This work provides the route to develop efficient and durable electrocatalyst for constructing ZABs with long lifespan and high‐power‐density. [ABSTRACT FROM AUTHOR]

In wall rock failure process, the electronic escape phenomenon normally occurs, which causes the change of the natural electric field in the coal rock. Through the establishment of a numerical model and design of a rock mining simulation experiment, the authors found the natural electrical potential of rock at crack development site is reduced, and it is much lower with a full fracture development, while the natural electrical potential increases at rock compression area. The findings in the monitoring in coal mine mining demonstrate that in the three zones of seam roof, the natural electrical potential is low and stable at caving zone; more unstable and frequent alternation at crack development zone; high, stable and less changes at bending sink zone. Natural electrical potential alternation plays a guiding role and has practical significance for determining the fracture development level and scope of fracture zones at coal seam floor and roof. [ABSTRACT FROM AUTHOR]