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Standard reference data is a type of high-quality scientific data and has both metrological and technical standard attributes; therefore, it is an important national science foundation and strategic resources. Research on the standard reference data in China lags significantly behind the advanced world level, causing potential risks to scientific research and production. This study explores the scientific connotation, extended characteristics, and strategic values of standard reference data, and analyzes the progress, management system, international influence, and practical application of standard reference data in the United States. Moreover, the current status of standard reference data development in China is viewed, key problems such as unclear concept, insufficient top-level design, lack of data resource accumulation, and missing management system are highlighted, and a construction path for standard reference data in China is proposed. Furthermore, the study recommends establishing a sound policy system for standard reference data, strengthening the financial guarantee for relevant research, strengthening publicity and education to accelerate the cultivation of talents, and encouraging international cooperation.

Rubble-pile asteroids may be the type of near-Earth object most likely to threaten Earth in a future collision event. Small-scale impact experiments and numerical simulations for large-scale impacts were conducted to clarify the size ratio of the boulder/projectile diameter effects on ejecta size–velocity distribution. A series of small-scale impact cratering experiments were performed on porous gypsum–basalt targets at velocities of 2.3 to 5.5 km·s−1. Three successive ejection processes were observed by high-speed and ultra-high-speed cameras. The momentum transfer coefficient and cratering size were measured. A three-dimensional numerical model reflecting the random distribution of the interior boulders of the rubble-pile structure asteroid is established. The size ratio (length to diameter) of the boulder size inside the asteroid to the projectile diameter changed from 0.25 to 1.7. We conducted a smoothed particle hydrodynamics numerical simulation in the AUTODYN software to study the boulder size effect on the ejecta size–velocity distribution. Simulation results suggest that the microscopic porosity on regolith affects the propagation of shock waves and reduces the velocity of ejecta. Experiments and numerical simulation results suggest that both excavation flow and spalling ejection mechanism can eject boulders (0.12–0.72 m) out of the rubble-pile asteroid. These experiments and simulation results help us select the potential impact site in a planetary defense scenario and reduce deflection risk. are comprised primarily of boulders of a range of sizes. [ABSTRACT FROM AUTHOR]

To solve the problem where the prediction formula for vibration velocity by dynamic compaction cannot fully reflect the elevation amplification effect, the elevation amplification effect of vibration velocity by dynamic compaction was studied theoretically, and the factors that influence the elevation amplification effect of vibration velocity by dynamic compaction were systematically analyzed in this paper. The elevation amplification effect of a loess high slope under dynamic compaction is coformed by the refraction and reflection superposition effect of dynamic compaction vibration waves at the soil layer interface and the diffraction effect of dynamic compaction vibration waves. The propagation path of dynamic compaction vibration waves in soil was analyzed, and the elevation amplification effect was verified theoretically. The related physical quantities that affected the dynamic compaction vibration velocity of a loess high slope were analyzed based on the dimensional analysis method, and the calculation and improved calculation formulas that considered the elevation amplification effect of dynamic compaction vibration velocity were obtained. The multiple regression analysis of the calculation and improved calculation formula that considered the elevation amplification effect of the dynamic compaction vibration velocity was carried out using MATLAB with engineering examples. The results show that the relative error of the two formulas is small when the elevation difference is small; when the elevation difference is large, the calculation accuracy of the improved calculation formula that considered the elevation difference is higher, and it is more in line with the actual situation. Finally, according to the selected maximum allowable value of the slope particle velocity (e.g., 1.5, 2.0, and 2.5 cm/s), the allowable safe distance for dynamic compaction on a loess high slope is proposed area of northern Shaanxi Province, China. The results of this paper could provide a reliable basis for predicting vibration velocity by dynamic compaction in the Loess Plateau area of northern Shaanxi Province, China. They might have a reference value for dynamic compaction vibration control under similar terrain environments with large elevation differences and provide a safe guide for a dynamic compaction construction site in the Loess Plateau area of northern Shaanxi Province, China. [ABSTRACT FROM AUTHOR]

Freeze–thaw (FT) erosion intensity may exhibit a future increasing trend with climate warming, humidification, and permafrost degradation in the Qinghai–Tibet Plateau (QTP). The present study provides a reference for the prevention and control of FT erosion in the QTP, as well as for the protection and restoration of the regional ecological environment. FT erosion is the third major type of soil erosion after water and wind erosion. Although FT erosion is one of the major soil erosion types in cold regions, it has been studied relatively little in the past because of the complexity of several influencing factors and the involvement of shallow surface layers at certain depths. The QTP is an important ecological barrier area in China. However, this area is characterized by harsh climatic and fragile environmental conditions, as well as by frequent FT erosion events, making it necessary to conduct research on FT erosion. In this paper, a total of 11 meteorological, vegetation, topographic, geomorphological, and geological factors were selected and assigned analytic hierarchy process (AHP)-based weights to evaluate the FT erosion intensity in the QTP using a comprehensive evaluation index method. In addition, the single effects of the selected influencing factors on the FT erosion intensity were further evaluated in this study. According to the obtained results, the total FT erosion area covered 1.61 × 106 km2, accounting for 61.33% of the total area of the QTP. The moderate and strong FT erosion intensity classes covered 6.19 × 105 km2, accounting for 38.37% of the total FT erosion area in the QTP. The results revealed substantial variations in the spatial distribution of the FT erosion intensity in the QTP. Indeed, the moderate and strong erosion areas were mainly located in the high mountain areas and the hilly part of the Hoh Xil frozen soil region. [ABSTRACT FROM AUTHOR]

The complex relationship between aboveground and belowground diversity and whether they act as surrogates for one another remains unresolved. Increasing evidence suggests that investigating phylogenetic diversity could provide valuable insights into the interplay between plants and soil microbes, but the proliferation of phylogenetic diversity metrics has hindered comparative studies and the identification of general patterns. To overcome this challenge, we implemented a multi‐dimensional framework that classifies phylogenetic diversity metrics into three dimensions: richness, divergence, and regularity, each of which captures different ecological aspects of species differences. Then we applied this framework to investigate the relationship between above and belowground diversity in a subtropical forest in eastern China. We found that phylogenetic diversity of plant and soil microbes, including bacteria and fungi, were more strongly correlated at the richness and regularity dimensions compared with divergence dimension. Further analyses revealed that these observed correlation patterns align with variations in soil total phosphorus content, a key factor influencing both plant and microbial phylogenetic diversity at richness and regularity dimensions. Together, our study demonstrated the necessity of using a multi‐dimensional approach to advance our understanding of the complex relationships between plant and soil microbial biodiversity. [ABSTRACT FROM AUTHOR]