Abstract: This study evaluated the efficacy of genetically engineered Streptomyces strain PSQ for remediating cadmium (Cd)-contaminated mine soils in Hunan Province, where agricultural soils exhibit elevated Cd levels. A pot experiment was conducted with three treatments: blank control (CK), wild-type Streptomyces strain FQ1, and engineered strain PSQ. Soil physicochemical properties, plant heavy metal uptake, and microbial community dynamics were systematically assessed. Results showed that PSQ altered soil pH and redox potential, thereby influencing Cd mobility. Leachate Cd concentration was significantly higher in the PSQ treatment (2.325 mg/L) than in CK (1.89 mg/L), reflecting increased Cd solubility via microbial metabolism. However, bioavailable Cd decreased by 15.8% in PSQ-treated soil (mean 0.16 mg/kg) compared to CK (0.19 mg/kg), indicating effective Cd immobilization through complexation, reduction, and adsorption mechanisms. Plant uptake was enhanced in the PSQ group, with higher mean bioconcentration factors (BCF) for Cd relative to CK and FQ1 treatments. Notably, Amaranthus tricolor and Cyperus iria displayed strong Cd accumulation (BCF > 7), suggesting improved phytoextraction efficiency promoted by the engineered strain. The Alpha diversity of PSQ and FQ1 groups was lower than that of the CK group, but the intra-group differences were significant. The key microbial community was Saccharibacillus. Overall, strain PSQ reduced bioavailable Cd, augmented plant Cd enrichment, and modulated rhizosphere microbial communities, establishing a synergistic system involving exogenous engineered bacteria, indigenous microbiota, and plants. These findings provide a theoretical basis for bioremediation of Cd-contaminated soils. Read More

Abstract: To investigate in detail the evolution characteristics of lithofacies and sedimentary facies belts within a sequence stratigraphic framework, the sequence stratigraphic framework of the lower member of the Shimengou Formation in the Yuka area was established based on field drilling core descriptions. Single-factor isoline maps were drawn according to systems tracts, and the lithofacies paleogeography was reconstructed. Read More

Abstract: Against the backdrop of global climate warming and intensified human activities, geological hazards triggered by heavy rainfall pose an increasingly prominent threat to the regional ecological environment as well as to human life and property. Taking Huixian City, Henan Province, as the study area, this paper systematically investigates the triggering factors and mechanisms of geological hazards induced by heavy rainfall through a combination of literature review, field sampling, and laboratory testing. First, the geological environmental conditions of Huixian City, including topography, stratigraphy and lithology, and meteorological-hydrological characteristics, were reviewed. Second, the physical and mechanical properties of typical silty clay in the study area were analyzed through direct shear tests and soil-water characteristic curve tests. The results show that the geological hazards in the area are mainly small- and medium-scale collapses, landslides, and debris flows, which are concentrated in low- to middle-mountainous and hilly areas and are highly consistent with heavy rainfall during the flood season (June to October) in both temporal and spatial distribution. The shear strength first increases and then decreases with increasing water content, cohesion reaches its peak at the optimum water content, and matric suction is significantly negatively correlated with water content. Finally, the core mechanism is clarified: heavy rainfall increases the water content of rock and soil masses, softens the rock-soil structure, and reduces the shear strength of the rock mass, thereby triggering geological hazards. The results of this study can provide a scientific basis and technical support for the monitoring, early warning, prevention, and control of geological hazards in Huixian City and other areas prone to similar geological hazards. Read More

Abstract: Urban transformation is a critical development issue facing resource-depleted cities. Examining the mechanisms and driving factors of such transformation from a resilience perspective is of great significance for achieving high-quality development in resource-based cities. This paper constructs an urban resilience measurement index system based on four dimensions—economic, social, engineering and ecological—and employs the entropy method and Partial Least Squares (PLS) to conduct a quantitative assessment of Jiaozuo City’s urban resilience across different dimensions and phases from 2000 to 2021. The results indicate that: (1) Jiaozuo’s urban resilience underwent three phases—low resilience (2000–2007), moderate resilience (2008–2015) and high resilience (2016–2021)—with its resilience level exhibiting a ‘slow–rapid–slow’ upward trend. (2) Between 2000 and 2021, the driving factors behind Jiaozuo’s resilience evolution shifted gradually from economic resilience indicators and innovation-related indicators within social resilience to a combined drive from resilience indicators across all dimensions. Among these, factors such as the foundation of regional development, the level of openness to the outside world, innovative development, government management and the ecological environment were key drivers of Jiaozuo’s resilience evolution. Based on the identified primary drivers of resilience and applying the theory of evolutionary economic geography, this study summarises the transformation mechanisms to provide a reference for the transformation of other resource-depleted cities, thereby facilitating the cultivation of new-quality productive forces in such cities. Read More

Abstract: Taking Qilian Mountain National Park as the study area, this research systematically analyzed the spatiotemporal evolution characteristics and driving mechanisms of carbon sources/sinks in the park based on the MOD17A3HGF net primary productivity (NPP) dataset and meteorological data including temperature, precipitation, humidity, and sunshine duration from 2000 to 2022. The methods applied included a net ecosystem productivity (NEP) estimation model, pixel-wise linear regression, and correlation analysis. The results showed that: From 2000 to 2022, the park’s NEP exhibited a fluctuating upward trend with a slope of 1.89 gCm2a, reaching a peak of 181.6 gCm2a in 2019. The region was dominated by carbon sinks overall, with carbon source areas accounting for less than 0.5% and showing a decreasing trend. Spatially, NEP was higher in the southeast and lower in the northwest. High-value areas were concentrated in the Eastern Qilian Mountains spruce forest–alpine meadow and Hexi Corridor arid desert–oasis agricultural ecological subzones, while low-value areas were distributed in the Qaidam Basin desert, Western Qilian Mountains alpine desert steppe, and Qinghai Lake Wetland alpine meadow subzone. NEP showed an increasing trend across all five ecological subzones, with growth rates ranked as: Hexi Corridor (3.88) > Eastern Qilian Mountains (2.31) > Western Qilian Mountains (1.3) > Qaidam Basin (1.02) > Qinghai Lake Wetland (0.25). An increasing NEP trend occurred in 98.8% of the park area, among which 73.4% showed an extremely significant increase. NEP was positively correlated with meteorological factors; temperature was the primary driving factor, followed by precipitation and humidity, while sunshine duration had a relatively weak effect. This study can provide a scientific basis for ecological conservation, restoration, and carbon sink enhancement in Qilian Mountain National Park. Read More

Abstract: Technological progress is the key to promoting efficient agricultural production and an important means and fundamental approach to achieving high-quality agricultural development. This paper uses panel data from the Yangling Agricultural High-tech Industrial Demonstration Zone from 2010 to 2020 as an example, calculates the agricultural technological progress index from 1998 to 2018 based on the DEA-Malmquist index model, and finally explores the causal relationship between the two using a Two-way fixed effects model. The results show that the technological progress index of the Yangling Agricultural High-tech Industrial Demonstration Zone is on an upward trend; technological progress has a negative impact on agricultural pollution, that is, technological progress can inhibit the spatial spillover of agricultural pollution and relatively reduce environmental pollution. Therefore, there is a significant causal relationship between agricultural technological progress and the spatial spillover of agricultural pollution in the Yangling Agricultural High-tech Industrial Demonstration Zone. The region can start with technological progress, expand the scope of agricultural technology use and increase the utilization rate of high-tech agricultural machinery, which can reduce local and neighboring agricultural pollution to a certain extent and promote the healthy development of local agriculture. Read More

Abstract: In order to clarify the sedimentary characteristics of restricted braided river deltas under the control of paleogeomorphology in the Jingjingzigou Formation of the Ji 451 well area in the Jimusar Sag, establish sedimentary models, and understand the distribution patterns of sedimentary sand bodies. A variety of methods, including paleogeomorphologic restoration, logging facies description, lithofacies and sedimentary facies classification, were comprehensively employed to conduct the research. The research indicates that (1) The study area features a paleogeomorphic pattern of "southern bulge and northern depression," with the Jinan uplift developing in the south and a paleolake in the north, separated by a slope formed by the movement of the two fault blocks of the Jinan Fault in the middle. (2) In the second member of the Jingjingzigou Formation in the study area, channel deposits are predominantly developed. Based on lithological characteristics and single-well sedimentary facies analysis, they can be classified into underwater distributary channel and inter-distributary bay microfacies. The underwater distributary channels are distributed in large sets, with interbedded deposits of inter-distributary bays and underwater distributary channels. (3) After being denuded, the clastic materials from the Jinan uplift were transported northward along the slope to the lake basin. With a slope developed in the northern part of the lake basin, the sediments carved out multiple braided channels there. During the transportation process, as the northern shore of the lake basin features a sloped terrain, the sediments are unable to overcome their own gravitational force to continue being transported forward. Ultimately, they accumulate within the lake basin, forming sedimentary bodies that are spatially restricted by the lake basin, with a limited distribution range. These sedimentary bodies differ from the braided river deltas in the traditional sense. In the study area, it … Read More

Abstract: As urbanization accelerates, the urban heat island (UHI) effect increasingly impacts the ecological environment and residents' thermal comfort. Greenways, functioning as multifunctional linear green open spaces, play a vital role in improving the urban thermal environment. However, the mechanisms by which internal spatial characteristics affect microclimate and thermal comfort remain unclear. Taking 10 spatial types within the Qingshan Lake Greenway as a case study, this research utilized measured microclimatic data to calculate the Physiological Equivalent Temperature (PET), revealing the spatiotemporal variations of thermal comfort within the greenway. Concurrently, an indicator system for greenway spatial characteristics was established. Correlation analysis and stepwise regression models were applied to uncover the impact mechanisms of various spatial features on the microclimate and thermal comfort. The results indicate that: (1) Within the Qingshan Lake Greenway, the degree of shading exerts a more substantial influence on human thermal comfort than water body area. The comprehensive thermal comfort across different periods ranked as follows: 17:30–18:30 > 09:30–10:30 > 16:30–17:30 > 10:30–11:30. (2) Greenway spatial characteristics significantly influence air temperature, relative humidity, and globe temperature, whereas the effects on wind speed and solar radiation are comparatively minor. (3) The green space ratio, green view index (GVI), permeable surface ratio, spatial coverage, spatial enclosure, and sky view factor (SVF) significantly affect human thermal comfort. The stepwise regression equation linking average PET to these influencing factors is expressed as: PETmean = 40.261 + 1.157 * green space ratio – 1.331 * subsurface permeability rate – 5.390 * coverage degree. These findings provide crucial guidance for optimizing the internal spaces of suburban greenways and enhancing the thermal comfort of human settlements. Read More

Abstract: Rural revitalization in contemporary China has progressed through successive policy frameworks, from physical environmental improvement under the Beautiful Countryside campaign to the more systemic ambitions of the Future Village initiative, which seeks to reconstruct rural communities as economically viable, ecologically sustainable, and digitally empowered units within the broader metropolitan economy. This paper presents an integrated planning framework developed for Tianmu Village, a mountain rural settlement located in Tianmu Mountain Township, Lin'an District, Hangzhou, Zhejiang Province. Situated at the gateway to the West Tianmu Mountain UNESCO Man and Biosphere Reserve, the village possesses an exceptional convergence of ecological landscape assets, layered cultural heritage, and an established rural hospitality economy — conditions that create both significant development opportunity and heightened risk of asset erosion through uncoordinated growth. The planning framework responds through five coordinated strategic interventions: comprehensive environmental remediation, targeted infrastructure and service improvement, thematic connectivity across dispersed heritage and landscape assets, industrial integration centered on bamboo culture, and digital empowerment of governance and visitor experience systems. The framework argues that durable rural tourism competitiveness depends not on the accumulation of generic amenities but on the articulation of a coherent, place-specific cultural identity grounded in the intersection of Tianmu's bamboo productive landscape, mountain ecological character, and multi-layered settlement heritage. The governance dimensions of the proposal — including a federated homestay quality management structure and a village-scale digital platform integrating smart tourism, agricultural monitoring, and community service delivery — are argued to be as critical to long-term success as the physical planning interventions themselves Read More

Abstract: With the increasing difficulty of coal mining and the rapid growth of science and technology, coal mining enterprises have higher requirements for roadway excavation and support technology. In practical applications, it is necessary to select the appropriate roadway driving and supporting technology to ensure the safety of underground production. Based on this, the factors and application characteristics of roadway driving and supporting technology in the process of coal mining are analyzed, and the practical application of roadway driving and supporting technology in coal mining engineering is also expounded. Read More

Abstract: To clarify the shear mechanical response and crack evolution of bolted jointed rock masses under impact disturbance, a mesoscopic particle flow model of the “rock mass-joint-bolt” system was established using PFC2D. The mechanical behavior and damage evolution of bolted jointed rock masses under impact-shear coupling were systematically investigated under different impact numbers, impact patterns, and confining pressures. The results show that, after impact disturbance, the shear stress-shear displacement curve of the bolted jointed rock mass can be divided into four stages: elastic stage, stress-drop stage, strengthening stage, and residual stage, while the normal displacement-shear displacement curve undergoes three stages: shear contraction, dilation, and softening. With the increase in impact parameters, the shear modulus, peak shear stress, and residual strength generally decrease, the normal restraint capacity weakens, the joint closure increases, and the peak normal displacement decreases. With increasing confining pressure, the shear strength and residual bearing capacity are enhanced, whereas the dilation behavior is significantly restrained. Based on the evolution law of normal displacement, the peak dilation angle was defined and its degradation characteristics were analyzed. The results indicate that the peak dilation angle generally shows a trend of initial increase followed by decrease with increasing impact parameters, while its attenuation coefficient increases with confining pressure. Crack evolution analysis further shows that impact disturbance significantly promotes internal crack propagation in bolted jointed rock masses, and the number of cracks increases with impact parameters. As confining pressure increases, the total number of cracks further increases, whereas the proportion of tensile cracks decreases slightly. The study can provide a reference for the stability analysis and support design of bolted jointed rock masses subjected to impact … Read More

Abstract: To reveal the failure mechanism of anchorage systems with cylindrical reaming and clarify the internal correlation among anchorage failure, surrounding rock stress, and anchorage agent displacement, a three-dimensional integrated model of the surrounding rock-bolt-anchoring agent-reaming section was established using the Abaqus numerical simulation method based on the cylindrical reaming anchorage engineering in deep soft rock roadways. Seven groups of working conditions with different reaming diameters were designed. Combined with visual analysis of surrounding rock stress and anchorage agent displacement nephograms, as well as theoretical calculations, the failure characteristics, types, and evolution laws of the anchorage structure after reaming were systematically studied. The results show that anchorage failure in cylindrical reaming is dominated by damage to the anchoring agent, which manifests in three core forms: interfacial debonding, plastic rheology, and fracture. An unreasonable reaming diameter causes significant stress concentration at the junction of the reaming section and the reference borehole, and the degree of stress concentration has a nonlinear relationship with the reaming diameter, which is the core inducement of anchorage failure. The displacement and deformation of the anchoring agent increase with the deviation of the reaming diameter from the optimal value, and the deformation concentration area is highly coincident with the stress concentration area, which directly determines the type and degree of anchorage failure. The optimal reaming diameter is 40 mm. Under this condition, the surrounding rock stress is uniformly distributed, the displacement and deformation of the anchoring agent are the smallest, and the risk of anchorage failure is the lowest. The research results provide an intuitive theoretical basis for parameter optimization and failure prevention and control of cylindrical reaming anchorage technology. Read More

Abstract: Aiming at the issue of inconsistent cell voltages in series-connected power battery packs for new energy vehicles, this paper investigates voltage balancing circuits, with the goal of preventing the degradation of overall battery pack performance and service life caused by this problem. The study investigates a passive balancing circuit using resistors as energy dissipation components and an active voltage balancing circuit employing capacitors as energy storage and transfer devices. Simulation analyses of both balancing circuits are carried out in the MATLAB environment. The results demonstrate that the single-capacitor method exhibits distinct advantages in terms of energy efficiency, balancing speed, and system reliability, thus providing a more advanced and practical solution for voltage balancing of power batteries in new energy vehicles. Read More

Abstract: To address the engineering challenges of low anchorage capacity, easy shear debonding failure at the anchorage interface, and the difficult long-term stability control of the roof in deep coal mine soft-rock roadways, a refined 3D numerical model was established in Abaqus based on the bolt-adhesive-surrounding rock collaborative bearing theory and the interfacial shear transfer theory. The influence of cylindrical straight reaming diameter on bolt pull-out behavior was systematically investigated. Seven reaming diameters (24, 30, 40, 50, 60, 70, and 80 mm) were used to analyze the peak pull-out force, load evolution characteristics, stress distribution of the anchorage agent, interfacial load transfer characteristics, and the evolution of anchorage failure modes. Results show that the peak pull-out force exhibits a three-stage trend: rapid increase, slight decrease, and gradual rise with rising reaming diameter. At a 40 mm reaming diameter, the anchorage agent stress distribution is relatively uniform, local stress concentrations are low, and the collaborative bearing state is ideal, yielding a peak pull-out force of 143 kN, which can be used as a reasonable engineering reaming diameter. When the reaming diameter exceeds 50 mm, the effective bearing thickness of the surrounding rock is insufficient; the borehole wall rock gradually enters a plastic softening state; the effective shear capacity decreases; and the pull-out force declines. Within 60–80 mm, the gain from increased contact area compensates to some extent for the weakening of the surrounding rock, and the pull-out force continues to rise. However, surrounding rock damage is severe, construction costs increase significantly, and the engineering practical value is limited. This study can provide a sufficient theoretical basis and reference for mechanism analysis, parameter optimization, and engineering design of reaming bolt support. Read More

Abstract: To accurately grasp the failure pattern of the overlying strata under the conditions of top-coal caving mining in the thick coal seam of the 13050 working face at Yunding Coal Industry, a systematic study was conducted on the development height and distribution characteristics of the "three zones" (caved zone, water-conducting fracture zone) in the overlying strata. This study was based on the geological and mining conditions of the working face and utilized a combination of theoretical calculations, downhole borehole television measurements, and 3DEC numerical simulation. The results show that the theoretical calculation yielded a caved zone height of 10.48–14.88 m and a water-conducting fracture zone height of 39.77–58.83 m. The field measurements indicated a caved zone height of 12.93–20.21 m and a water-conducting fracture zone height of 38.79–60.63 m. The numerical simulation showed a maximum water-conducting fracture zone height of approximately 43.9 m. The results from the three methods exhibit a high degree of agreement. Consequently, the caved zone height for this working face is determined to be 13–16 m, and the water-conducting fracture zone height is determined to be 40–44 m. This can provide a reliable basis for roof control, the design of waterproof coal/rock pillars, and safe mining operations at the working face. Read More

Abstract: Aiming at the engineering challenge of large surrounding rock deformation and conventional support failure in soft rock roadways under deep high stress and intense mining-induced conditions, this paper takes the 1101 roadway of Hudi Coal Mine as the engineering background. Adopting a combined method of theoretical analysis, numerical simulation, and field tests, this paper reveals the hierarchical coupling control mechanism of high-strength anchor cables and grouting reinforcement, optimizes and determines the support parameter system of "short anchor cables + long anchor cables + deep-shallow grouting" based on ϕ28.6 mm large-diameter high-strength anchor cables, and carries out industrial field tests. The results show that, compared with the original support scheme, the convergence of the two roadway sides, roof subsidence, and floor heave are reduced by 47.9%, 46.2%, and 40.1% respectively with the proposed technology. The surrounding rock deformation is effectively controlled, which provides a technical reference for surrounding rock stability control of similar deep soft rock roadways under strong dynamic pressure Read More

Abstract: With the acceleration of urbanization, urban islands are undergoing a spatial transformation from ecological conservation areas to new growth poles for urban development. In this process, gentrification plays a crucial role, profoundly reshaping both the physical and social spaces of these islands. Taking Jiangxinzhou in Nanjing as a case study, this paper employs a combination of field surveys and online textual analysis to explore the characteristics of spatial perception of urban islands under the influence of gentrification. The results indicate that Jiangxinzhou has experienced significant changes in ecological environment, road transportation, architectural style, public amenities, and cultural and recreational spaces. Overall, public sentiment toward these five categories of space is positive, with the highest satisfaction observed in public spaces, while cultural spaces exhibit the highest proportion of negative perceptions. During the development process, urban islands face several challenges, including conflicts between ecological preservation and aesthetic pursuits, lack of diversity in public transportation, monotonous building functions, insufficient public spaces, and the erosion of local culture. Based on these findings, this study proposes corresponding optimization strategies, aiming to provide references for the planning and development of urban islands in the context of gentrification. Read More