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2024, Volume 54,  Issue 5

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Earth and Space
Discovery of a geomorphological analog to martian araneiforms in the Qaidam Basin, Tibetan Plateau
Shengxing Zhang, Yiliang Li, Wei Leng
2024, 54(5): 0501. doi: 10.52396/JUSTC-2023-0164
Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars. A gas erosion process driven by the seasonal sublimation of CO2 ice was proposed as an explanation for their formation, which cannot occur on Earth due to the high climatic temperature. In this study, we propose an alternative mechanism that attributes the araneiform formation to the erosion of upwelling salt water from the subsurface, relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau. Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars. A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism. The simulation results indicate that the water-diffusion process, under varying ground conditions, may be responsible for the diverse araneiform morphologies observed on both Earth and Mars. Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks, which is consistent with observations of araneiforms on Mars and Earth. Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars.
Infrared microthermometry of fluid inclusion in sphalerite: A case study of the Xinqiao deposit in the Middle–Lower Yangtze metallogenic belt
Yangyang Wang, Yilin Xiao
2024, 54(5): 0502. doi: 10.52396/JUSTC-2023-0054
Infrared microthermometry allows direct measurement of fluid inclusions hosted in opaque ore minerals and can provide direct constraints on the evolution of ore-forming fluids. This study presents infrared microthermometry of spherite-hosted fluid inclusions from the Xinqiao deposit in the Middle-Lower Yangtze Metallogenic Belt and sheds new light on the ore genesis of the deposit. Considering that infrared light may lead to non-negligible temperature deviations during microthermometry, some tests were first conducted to ensure the accuracy of the microthermometric measurements. The measurement results indicated that using the lowest light intensity of the microscope and inserting an optical filter were effective in minimizing the possible temperature deviations of infrared microthermometry. All sphalerite-hosted fluid inclusions from the Xinqiao deposit were aqueous. They show homogenization temperature ranging from ~200 to 350 °C, but have two separate salinity groups (1.0–10% and 15.1–19.2% NaCl equivalent). The low-salinity group represents sedimentary exhalative (SEDEX)-associated fluids, whereas the high-salinity group results from modification by later magmatic hydrothermal fluids. Combined with published fluid inclusion data, the four-stage fluid evolution of the Xinqiao deposit was depicted. Furthermore, our data suggest that the Xinqiao deposit was formed by two-stage metallogenic events including SEDEX and magmatic-hydrothermal mineralization.
Impact of modified SWAT plant growth module on modeling green and blue water resources in subtropics
Tianming Ma, Tianxiao Ma
2024, 54(5): 0503. doi: 10.52396/JUSTC-2023-0023
The dynamics of water availability within a region can be quantitatively analyzed by partitioning the water into blue and green water resources. It is widely recognized that vegetation is one of the key factors that affect the assessment and modeling of blue and green water in hydrological models. However, SWAT-EPIC has limitations in simulating vegetation growth cycles in subtropics because it was originally designed for temperate regions and naturally based on temperature. To perform a correct and realistic assessment of changing vegetation impacts on modeling blue and water resources in the SWAT model, an approach was proposed in this study to modify the SWAT plant growth module with the remotely sensed leaf area index (LAI) to finally solve problems in simulating subtropical vegetation growth, such as controlling factors and dormancy. Comparisons between the original and modified model were performed on the model outputs to summarize the spatiotemporal changes in hydrological processes (including rainfall, runoff, evapotranspiration and soil water content) under six different plant types in a representative subtropical watershed of the Meichuan Basin, Jiangxi Province. Meanwhile, detailed analysis was conducted to discuss the effectiveness of the modified SWAT model and the impacts of vegetation changes on blue and green water modeling. The results showed that (1) the modified SWAT produced more reasonable seasonal curves of plants than the original model. ENS (Nash-Sutcliffe efficiency) and R2 increased by 0.02 during the calibration period and accounted for an increase of 0.09 and 0.03, respectively, during the validation period. (2) The comparison of model outputs between the original and modified SWAT suggested that evapotranspiration was more sensitive to vegetation changes than other components of green water. In addition, vegetation presented conservation capability in the blue water. (3) The variation in blue and green water resources with different plant types after modifying the SWAT model showed that seasonal changes in vegetation led to a significant difference between forest and non-forest areas.
The influence of different types of satisfaction on loyalty on C2C online shopping platform: From the perspective of sellers and the platform
Yanan Lu, Qian Huang, Yuting Wang
2024, 54(5): 1-14. doi: 10.52396/JUSTC-2022-0128
With the rise and development of major types of platforms, the competition for resources has become extremely fierce, and the market share of C2C platforms has been seriously threatened by the loss of resources. Therefore, building and maintaining buyers’ satisfaction and loyalty to C2C platforms is critical to the survival and sustainability of C2C platforms in China. However, the current knowledge on how platform satisfaction and loyalty are constructed in the C2C e-commerce environment is incomplete. In this study, seller-based satisfaction and platform-based satisfaction are constructed separately. We further distinguish seller-based transaction satisfaction into economic and social satisfaction and explore their antecedents and consequences. To test our research hypotheses, we conduct a survey and collect data from a real online market (Taobao website). The results show that seller-based transaction satisfaction positively affects platform-based overall satisfaction and loyalty; perceived product quality, perceived assurance, and perceived price fairness all have a significant effect on economic satisfaction, whereas perceived relationship quality and perceived empathy significantly influence social satisfaction. These findings help us understand the literature related to customer satisfaction in the context of C2C in China and provide inspiration for online sellers and platforms.
Evolutionary analysis of green credit and automobile enterprises under the mechanism of dynamic reward and punishment based on government regulation
Yu Dong, Xiaoyu Huang, Hongan Gan, Xuyang Liu
2024, 54(5): 1-15. doi: 10.52396/JUSTC-2023-0108
To explore the green development of automobile enterprises and promote the achievement of the ``dual carbonq target, based on the bounded rationality assumptions, this study constructed a tripartite evolutionary game model of government, commercial banks, and automobile enterprises; introduced a dynamic reward and punishment mechanism; and analyzed the development process of the three parties' strategic behavior under the static and dynamic reward and punishment mechanism. Vensim PLE (Personal Learning Edition) was used for numerical simulation analysis. Our results indicate that the system could not reach a stable state under the static reward and punishment mechanism. A dynamic reward and punishment mechanism can effectively improve the system stability and better fit real situations. Under the dynamic reward and punishment mechanism, an increase in the initial willingness of the three parties can promote the system stability, and the government can implement effective supervision by adjusting the upper limit of the reward and punishment intensity. Finally, the implementation of green credit by commercial banks plays a significant role in promoting the green development of automobile enterprises.