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[Objective] With the intensified influence of climate change and human activities, the climate and underlying surface conditions of the basins have changed. Accurately simulating the process of soil moisture change and analyzing its influencing factors are of great significance for regional water resource management and vegetation construction. [Methods] The Weihe River Basin in the Loess Plateau was taken as the research object. Based on the ABCD hydrological model, the EFAST method was used to analyze the parameter sensitivity of the model, and the constant parameter and time-varying parameter models were constructed. The runoff depth and soil water storage simulation accuracy of different parameter models were compared. The effects of climate change and vegetation restoration on soil water storage changes in the Weihe River Basin were discussed, and the dominant factors of soil water storage changes were clarified. [Results] The proportional parameter of soil water layer recharge groundwater c was the most sensitive, followed by the groundwater storage coefficient d, the upper limit parameter b of the sum of actual evapotranspiration and soil water storage, and the tendency parameter a of runoff that before the soil is completely saturated was the least sensitive. Compared with the ABCD constant parameter model, the time-varying parameter model increased the values of NSE, KGE, and R2 of the runoff depth simulation results by 19%, 10%, and 19%, respectively, and the NSE, KGE, and R2 of the verification period increased by 7%, 7%, and 9%, respectively. The time-varying parameter model significantly improved the runoff depth simulation results. The srtongest correlation between soil water storage in the Weihe river basin and ERA 5-Land 0-100 cm soil layer based on time-varying parameter model simulation, and the change process of the two agreed well. The degree of different influencing factors on the change of soil water storage in the Weihe River Basin from strong to weak was potential evapotranspiration>precipitation>NDVI. [Conclusion] The research results provide a scientific basis for water resources planning and management and vegetation construction in this area and they also provide references for soil water storage research in other similar areas.

In recent years, intelligent unmanned systems such as drones, autonomous vehicles, and unmanned boats have played a significant role in various fields, including military, industrial and agricultural production, and logistics transportation. However, due to the limitations in resources and capabilities of individual intelligent unmanned systems, they are unable to meet the increasingly complex demands of real-world applications. it has become a trend to organize multiple intelligent unmanned systems into clusters to achieve collaborative work and swarm intelligence, of which swarm navigation and positioning is an important basis for swarm intelligence.Traditional satellite navigation systems are inadequate to meet the application requirements of intelligent unmanned systems in complex environments. Therefore, autonomous navigation of intelligent unmanned swarm systems has become an urgent problem to solve. Inspired by the neural mechanisms and principles of animal navigation systems and collective coordination, brain-inspired swarm navigation has emerged as a promising research field. It aims to achieve efficient and intelligent navigation in complex and unknown environments, fulfilling the navigation needs of intelligent unmanned systems operating in groups. This article provides an overview of the concept and mechanisms of brain-inspired swarm navigation. It explores the spatial neural mechanisms involved in brain-inspired swarm navigation, relevant simulation models, and swarm intelligence algorithms for brain-inspired swarm decision-making. Finally, the future directions of brain-inspired swarm navigation are discussed.

Northwest China is strategically crucial for China’s economic development, social stability, and national defense security. However, the shortage of water resources and its fragile ecological environment have been hindering local economic development and life quality improvement for local residents. In this study, we analyze the characteristics of agricultural production and trade in Northwest China from 2000 to 2018 from the perspective of water footprint and virtual water, and clarifies the impact of virtual water flow on local water resources. Research shows that the water footprint regarding crop production in Northwest China showed a fluctuating upward trend from 2000 to 2018. The outflow scale of virtual water gradually increases alongside with the transfer-out of fruits and cotton. The outflow of virtual water regarding fruits and cotton in Northwest China was 3.212 × 1011 m3 in 2018, accounting for 69.8 % of the total water footprint regarding crop production. The Yellow River Basin is the primary inflow area of virtual water from Northwest China, and the region northwest to the “Qice line” is the primary outflow area of virtual water. Water shortage is severe in Northwest China and fruit and cotton are planted for trade to drive economic growth. Therefore, optimizing the crop planting and virtual water trade structures and encouraging inter-basin water transfer are key measures to regulate physical–virtual water cycle, alleviate the contradiction between water supply and demand, and ensure regional water security.

To maintain a reasonable sediment regulation system in the Loess Plateau, it is critical to determine the effects of check dam construction on sediment production and topographic changes. An indoor simulation experiment was conducted to investigate sediment production at the outlet section of the gully and micro‐topographic changes within the channel before and after dam construction. The results showed that check dam significantly affected the run‐off and sediment transport processes in the watershed. Specifically, the cross‐sectional morphology index (η) and the width‐depth ratio increased by 10.23% and 40.44%, respectively, while sediment content and particle size decreased by 39.29% and 18.58%, respectively. Additionally, the relative importance of section parameters and micro‐topographic parameters that affect sediment production rate and particle size was ranked using the random forest algorithm. The roughness after check dam construction was identified as a relatively important topographic factor affecting sediment production and particle selection by erosion. These findings provide valuable information for future check dam construction and development in the Loess Plateau region. [ABSTRACT FROM AUTHOR]

Elucidating the characteristics and underlying mechanisms of soil organic carbon (SOC) and nitrogen mineralization in the context of sludge addition is vital for enhancing soil quality and augmenting the carbon sink capacity of soil. This study examined the chemical properties, enzyme dynamics, and organic carbon and nitrogen mineralization processes of soil from degraded grasslands on the Loess Plateau at various incubation temperatures (5, 15, 25, and 35 °C) and sludge addition rates (0%, 5.0%, 10.0%, and 20.0%) through a laboratory incubation experiment. The results showed that incubation temperature, sludge addition, and their interactive effects significantly altered the soil enzyme C:N, C:P, and N:P stoichiometries. The cumulative mineralization rates of SOC and nitrogen increased significantly with increasing incubation temperature and sludge addition rate. Principal component analysis revealed a significant linear correlation between cumulative SOC and nitrogen mineralization. Random forest analysis indicated that β-1,4-Glucosidase (BG), β-1,4-N-acetyglucosaminidase (NAG), cellobiohydrolase (CBH), ammonium nitrogen (NO3−), enzyme C:P ratio, alkaline phosphatase (ALP), and incubation temperature were crucial determinants of cumulative SOC mineralization. Structural equation modeling demonstrated that sludge addition, NO3−, NAG, ALP, and enzyme C:P positively impacted SOC mineralization, whereas dissolved organic carbon and BG had negative impacts. Conversely, incubation temperature negatively affected soil nitrogen mineralization, whereas NO3−, available phosphorus, and ALP contributed positively. Sludge addition and temperature indirectly modulated soil net nitrogen mineralization by altering soil chemical properties and enzyme activities. These findings underscore the role of SOC and nitrogen mineralization as indicators for evaluating soil nutrient retention capabilities. [ABSTRACT FROM AUTHOR]