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Climate change is an important issue for cities today and in the future. At present, China has a large population and complex climate conditions, and cities are also vulnerable to the adverse effects of climate change (Tian, Environ Sustain Dev 6: 153-155 2020). Three-dimensional greening can not only improve the green space system of a city but also have a far-reaching impact on the ecology, image, and economic benefits of a city. Therefore, the study of urban three-dimensional greening is an effective means to deal with climate change strategies. By exploring the influence of traditional greening and three-dimensional greening on Local Climate in Beilin District of Xi'an, Shaanxi Province, the mechanism of three-dimensional greening on urban ecological environment was discussed, and the ecological theory, urban three-dimensional greening theory, and urban local climate zone (LCZ) were referred to. Based on the methods of national climate monitoring, ENVI-met simulation, and field independent measurement, this paper selected a research sample site in the east section of Jianshe Road, Beilin District, Xi'an City, Shaanxi Province, China, and applied ENVI-met software to simulate the thermal stress relationship among building exterior surfaces, plants, and air in the street; quantified the overall ecology of the area; and used measuring instruments. The influence of different types of greening in the base on the site temperature, humidity, CO2 (carbon dioxide) concentration, wind speed, and other climate factors data was, respectively, measured and analyzed. The grid analysis was used to compare the traditional greening and three-dimensional greening, then the numerical differences of each impact factor were sorted out, and the effect of three-dimensional greening on the improvement of urban ecological environment was discussed by analyzing the climate factors with greater impact. The results show that (1) three-dimensional greening plus traditional greening is the most beneficial mode; (2) in the same environment, according to the parameter of 1.5 m from the ground in the model environment, it can be seen that the temperature of the space treated with three-dimensional greening of buildings is reduced by 3.5–3.6 ℃ compared with the control group, the relative humidity is different by 7–8%, the CO2 concentration is reduced by about 5%, and the spatial wind speed is relatively small. (3) When the urban green coverage rate is more than 40%, the improvement of temperature is more obvious, if it reaches 50%, the cool phenomenon in summer can be fundamentally changed. From the perspective of human perception, the PMV index increased by 0.27 on average. This paper discusses and analyzes the three-dimensional greening of urban streets in Beilin District, Xi'an City, Shaanxi Province, China, and studies its influence on urban ecology to different degrees. The conclusions are as follows: Different types of greening have different degrees of influence on urban climate. Meanwhile, the experimental results of this paper show that in cities like Xi'an, Shaanxi Province, China, where summer is hot, adding three-dimensional greening to traditional street greening can significantly improve the environmental microclimate, which is an effective means to cope with climate change, improve the site environment, and stabilize the urban ecosystem. [ABSTRACT FROM AUTHOR]

This paper examines sandstones of varying particle sizes within the coal-bearing strata in the Fugu area of northern Shaanxi. Employing high-temperature heat treatment, the study performs tests at different temperatures (25 ~ 600 ℃) on rock samples under both oxygen and nitrogen environments. Utilizing nitrogen adsorption tests combined with fractal dimension analysis, we investigate the pore structure and fractal characteristics of sandstones with varying particle sizes in coal-bearing formations. The results indicate that the total pore volume (aperture range 0.35 ~ 500nm), specific surface area, and average pore diameter of sandstone increase with temperature. Moreover, smaller particles result in more pronounced changes in the sandstone's pore structure. At the same time, in comparison to the oxygen environment, sandstone treated in a nitrogen environment undergoes multiple occurrences of molecular layer nitrogen adsorption, leading to a higher degree of pore damage. In addition, the fractal dimension of sandstone pores decreases with rising temperature. Under high-temperature conditions, the pores undergo a transformation from the initial irregular crack structure to a homogenized pore structure. The weakening of non-uniformity contributes to the decrease in fractal dimension. [ABSTRACT FROM AUTHOR]

Historical records indicate that Xianyang Ancient Ferry Site, dating back over three millennia to the late Shang Dynasty, has been an important transportation hub in ancient times. The use of combined wooden stakes and stones is a special method for flood control among ancient flood prevention techniques. This research aims to evaluate the current preservation condition of these ancient wooden stakes. The dating of the wooden stakes at the site ranges between 940 ± 30 BP and 320 ± 30 BP. The fiber cross-section and microstructure images of the wooden samples indicate that the wood is attributed to Platycladus orientalis. SEM images indicate decay and deterioration of the wooden samples, with the presence of mold spores within the cavities. XRD, FTIR, and TG/DSC spectra of historical wooden samples collected from the site and fresh Platycladus orientalis wood samples demonstrate a significant decrease of cellulose crystallinity in the historical samples, leading to severe deterioration of the wood at the site. Five dominant mold species were identified, i.e., Aspergillus niger, Aspergillus flavus, Penicillium citrinum, Trichoderma, and Phanerochaete chrysosporium, which accelerate the degradation of cellulose and other polysaccharides. This research provides scientific evidence for the selection of reinforcement materials and guides curators and conservators to formulate conservation strategies in the future. [ABSTRACT FROM AUTHOR]

The construction of an ecologically livable rural environment requires treating rural domestic waste. Farmers, as key participants in rural domestic waste disposal, can improve the rural environment by disposing of domestic waste in an environmentally friendly manner. Few studies have examined the cadre–farmer relationship and its impact on rural waste pollution. Using a questionnaire survey of farmers in Shaanxi Province, China, this study estimates the effect of cadre–farmer relationship on their willingness to treat domestic waste. The findings indicate that a positive cadre–farmer relationship significantly increases farmers' willingness to treat domestic waste. This positive relationship can also strengthen the positive effects of institutional rules on waste treatment willingness. Further mechanism analysis shows that a good cadre–farmer relationship mobilizes farmers to protect the environment and to comply with national ecological laws and regulations, enhancing their willingness to treat domestic waste. These findings enrich research on rural domestic waste management. [ABSTRACT FROM AUTHOR]

Coal-rock interface identification technology was pivotal in automatically adjusting the shearer's cutting drum during coal mining. However, it also served as a technical bottleneck hindering the advancement of intelligent coal mining. This study aimed to address the poor accuracy of current coal-rock identification technology on comprehensive working faces, coupled with the limited availability of coal-rock datasets. The loss function of the SegFormer model was enhanced, the model's hyperparameters and learning rate were adjusted, and an automatic recognition method was proposed for coal-rock interfaces based on FL-SegFormer. Additionally, an experimental platform was constructed to simulate the dusty environment during coal-rock cutting by the shearer, enabling the collection of coal-rock test image datasets. The morphology-based algorithms were employed to expand the coal-rock image datasets through image rotation, color dithering, and Gaussian noise injection so as to augment the diversity and applicability of the datasets. As a result, a coal-rock image dataset comprising 8424 samples was generated. The findings demonstrated that the FL-SegFormer model achieved a Mean Intersection over Union (MIoU) and mean pixel accuracy (MPA) of 97.72% and 98.83%, respectively. The FL-SegFormer model outperformed other models in terms of recognition accuracy, as evidenced by an MIoU exceeding 95.70% of the original image. Furthermore, the FL-SegFormer model using original coal-rock images was validated from No. 15205 working face of the Yulin test mine in northern Shaanxi. The calculated average error was only 1.77%, and the model operated at a rate of 46.96 frames per second, meeting the practical application and deployment requirements in underground settings. These results provided a theoretical foundation for achieving automatic and efficient mining with coal mining machines and the intelligent development of coal mines. [ABSTRACT FROM AUTHOR]

Rural tourism development has an important impact on optimizing the rural industrial structure and stimulating local economic growth. China's Rural Revitalization Strategy has promoted the development of rural tourism nationwide and emphasized Chinese characteristics in the process of local development. Based on the theoretical analysis of landscape perception, this article uses the external Landscape Perception→Satisfaction→Revisit Intention influence path as a theoretical research framework to construct a structural equation model to analyze the willingness of tourists to revisit rural tourism destinations. We selected Nangou Village, Yan'an City, Shaanxi Province, as a key model village for rural revitalization, and conducted an empirical analysis. The empirical analysis results show that landscape perception has a significant positive impact on satisfaction and revisit intention. Tourist satisfaction has a significant positive impact on revisit intention and plays an intermediary role between landscape perception and revisit intention. The five dimensions of natural ecology, historical culture, leisure recreation, research experience, and integral route under landscape perception are all significantly positively correlated with revisit intention, with historical culture and integral route having the greatest impact on landscape perception. The survey about Nangou Village verifies the relationship between landscape perception, satisfaction, and tourists' revisit intention. Based on the objective data analysis results, this study puts forward suggestions for optimizing Nangou Village's tourism landscapes and improving tourists' willingness to revisit from three aspects: deeply excavating rural historical and cultural resources, shaping the national red culture brand, and creating rural tourism boutique routes. It is hoped that the quantitative research method of landscape perception theory in Nangou Village can also provide a reference and inspiration for similar rural tourism planning. [ABSTRACT FROM AUTHOR]

The coordinated development of land urbanization and population urbanization is crucial for the advancement of new urbanization. The study applied the entropy weight method and coupling coordination degree model, taking Shaanxi—a province in China characterized by a moderate pace of economic development and volume, along with distinct geographic and demographic features within its region—as the subject. It assessed the coordination conditions of these two types of urbanization from both macro and micro scales during the years 2010–2022. Utilizing the Analytic Network Process (ANP), the study ranked and analyzed the causes of issues stemming from uneven development, thus connecting a crucial link from theoretical analysis to decision-making implementation. The results showed that: (1) The province's land urbanization index was between 0.075 and 0.203, whereas the population urbanization index ranged from 0.221 to 0.408, with the development of the former significantly lagging behind the latter. (2) The coupling degree between land and population urbanization ranged from 0.835 to 0.854, with a coordination degree between 0.148 and 0.306. This indicated that a close connection had been formed between the two, yet a benign coupling relationship had not been established, displaying a spatial distribution characterized by "high in the middle, low in the north and south". (3) The limitation on further urban expansion was identified as the primary issue to be addressed (with a weight of 0.324), followed by insufficient infrastructure (with a weight of 0.261). The extent of ecological environmental damage was comparatively lower (with a weight of 0.225), and the degree of social injustice was the lowest (with a weight of 0.191). Therefore, to alleviate the problems associated with the imbalanced development between land urbanization and population urbanization, measures such as optimizing land spatial layout, enhancing urban ecological service functions, and strengthening the central cities' radiating effect should be implemented. [ABSTRACT FROM AUTHOR]

China's need for energy resources is growing every day. Future energy demands will be partly met by low-temperature pyrolysis of oil-rich coal, which is a form of coal-to-oil technology. Under the existing fully-mechanized coal mining technology, oil-rich coal is mechanically broken into different particle sizes by a shearer and used in different industrial utilization directions. However, due to differences in particle size and material composition, the pyrolysis products of oil-rich coal with different natural particle sizes are different, which affect the pyrolysis efficiency of oil-rich coal with different particle sizes. In order to explore the differences and influencing factors of pyrolysis products of oil-rich coal with different particle sizes, and taking Jurassic oil-rich coal in northern Shaanxi as the research object, the differences and causes of pyrolysis production of oil and gas from nine kinds of oil-rich coal with different natural particle sizes under existing coal mining conditions are discussed according to particle size characteristics, pore structure, heat transfer velocity and molecular structure. The findings demonstrate that the pyrolysis characteristics of coal do not show a single trend with change in particle size. With decrease in particle size, the ash and sulfur contents were relatively high, and the tar yield increased first and then decreased. In contrast, the light fraction decreased overall, and the heavy fraction decreased. The tar yield of 0.125–0.25 mm was the highest, and the tar content was 1.996 g. For the gas components produced by pyrolysis, the contents of CH4, CO and H2 first increased and then decreased with decrease in particle size, while the contents of CO2 and CnHm showed the opposite trend. Larger particles (about 30 mm) affect the escape efficiency of pyrolysis products and the amount of carbon deposition due to the difference in porosity (interparticle resistance) of the inner surface and pyrolysis bed, resulting in secondary reactions of the products escaped from a primary reaction, thus affecting the differences in pyrolysis products. The heat transfer process of coal was affected by particle size, and the thermal conductivity increased gradually with decrease in particle size, which is consistent with the change of tar yield with particle size. The maceral components and molecular structure functional groups in coal with different particle sizes were also different, which resulted in the differences in tar yield. Studies have shown that smaller particle sizes have longer alkyl side chains, and pyrolysis accompanied by rising temperature causes different changes in the aliphatic hydrocarbon content in coal coke after pyrolysis. The aliphatic hydrocarbon content decreased the most when the particle size was 0.125 mm, which is more beneficial to the improvement of tar yield. In addition, vitrinite is a good carrier of tar yield, and the granular coal vitrinite after crushing is enriched to smaller particles. [ABSTRACT FROM AUTHOR]

Microbially mediated carbon cycling is essential for the production of refractory dissolved organic carbon and subsequent formation of stable carbon sinks at the sediment–water interface (SWI) in aquatic ecosystems, such as lakes. It remains unclear how this process is influenced by hydrostatic pressure changes due to water level fluctuation in deep-water reservoirs. Here, a microcosm simulation experiment was carried out to decipher the response of microbially mediated carbon cycling to various hydrostatic pressures (i.e., 0.1 MPa [atmospheric pressure], 0.2 MPa, 0.5 MPa, 0.7 MPa) at the SWI in Jinpen Reservoir, Shaanxi Province, China. The response mechanisms of microbial community structure, functional gene abundance, and metabolic pathway activity associated with carbon cycling were explored by metagenomics and metabolomics. Results showed that the number of microbial species in sediment samples increased with elevating pressure. The relative abundance of archaea also increased from 0.2% to 0.4% as a consequence of pressure elevation, accompanied by 0.17% and 0.03% decrease in bacteria and fungi, respectively. In contrast with low pressures, high pressures allowed the microbial communities to form a more closely connected network, which maintained more complex interspecies interactions and greater system stability. High pressures additionally improved the abundances of specific functional genes (e.g., ALDO, ACO, sdhA, and sdhC) in carbon metabolic pathways, promoted carbon fixation by the reductive pentose phosphate (Calvin) and citrate cycles, and hindered methanogenesis. Piezophilic taxa (e.g., Gammaproteobacteria, Alphaproteobacteria, Bacteroidetes) and genes (e.g., ompH, asd) were identified among carbon cycling-associated microbial communities. The piezophilic genes, which were mainly present in the Proteobacteria phylum, increased first and then decreased in abundance with elevating pressure. The findings indicate that elevated hydrostatic pressure contributes to carbon sequestration at the SWI in deep-water reservoirs by changing carbon cycling-associated microbial species, as well as relevant functional genes and metabolic pathways. Highlights: • Metagenomics and metabolomics unravel microbial mechanisms of C cycling at the sediment–water interface of reservoirs • Distinct microbes contribute to C cycling, with improved community stability at high hydrostatic pressures • Elevated pressure leads to enrichment of specific functional genes and metabolites in C fixation pathways • Elevated pressure enhances the potential for microbially mediated C sequestration at the interface [ABSTRACT FROM AUTHOR]

The South Jingyang tableland, located in Shaanxi Province, China, is composed of loess deposits. Agricultural irrigation in this area has caused the continuous rise of the groundwater table, which triggered a series of loess landslides. Although extensive research has been conducted on the effect of rising groundwater tables on induced loess landslides, less is known about the groundwater table distribution. This study jointly investigated the distribution of the groundwater table in the South Jingyang tableland using boreholes, electrical resistivity tomography (ERT), and laboratory tests. A qualitative analysis between the apparent resistivity and the water content was estimated at different depths, using the borehole data and ERT inversion data. A quantitative relationship between the resistivity and the water content was established in the laboratory tests. A combination of the qualitative analysis of the inversion results and the quantitative relationship was used to determine the distribution of the groundwater table. The groundwater table is present at the depth where the water content of the loess is 30% (liquid limit of loess) and the resistivity is 28.35 Ω m. The groundwater table elevation in the southern study area is higher than that of the northern study area and decreases in a stepwise gradient from south to north. This study not only identified the distribution of the groundwater table in the South Jingyang tableland, but also makes up for the limitation and inaccuracy in determining groundwater tables by relying solely on the borehole information or inversion results of ERT. The ascertained distribution characteristics of the groundwater table provides a basis for the analysis of the formation mechanism of landslides. [ABSTRACT FROM AUTHOR]

The study specifically focused on the Hongliulin mining area, where a total of 40 soil samples were meticulously collected and analyzed from within a 1000 m radius extending from the tailings dam. The findings revealed that soil pH within the 0–1000 m range generally leaned towards the alkaline side. In terms of soil nutrient content, encompassing factors such as soil organic matter (SOM), total nitrogen (TN), total phosphorus (TP), total potassium (TK), alkali nitrogen (AK), available phosphorus (AP), and quick-acting potassium (AK), the variations fell within the following ranges: 2.23–13.58 g/kg, 0.12–0.73 g/kg, 0.18–1.15 g/kg, 9.54–35.82 g/kg, 2.89–6.76 mg/kg, 3.45–11.25 mg/kg, and 5.86–130.9 mg/kg. Collectively, these values indicate relatively low levels of soil nutrients. Within the 0–500 m range of soil samples, the average concentrations of Cd, Hg, Pb, and As were 0.778, 0.198, 24.87, and 17.92 mg/kg, respectively. These concentrations exceeded the established soil background values of Shaanxi Province and emerged as the primary pollutants in the study area. Within this same range, the mean values of eight toxic metals (Pi) were ranked in the following descending order: 1.726 (Hg), 1.400 (As), 1.129 (Cr), 1.109 (Pb), 0.623 (Zn), 0.536 (Cd), 0.309 (Cu), and 0.289 (Ni). With the exception of Hg, As, Cr, and Pb, which exhibited slight pollution, the other toxic metals were found to be within acceptable pollution limits for this sampling range, in line with the results obtained using the geo-accumulation index method. The average potential ecological risk index for the eight toxic metals in the study area stood at 185.0, indicating a moderate overall pollution level. When assessing individual elements, the proportions of ecological risk attributed to Hg, As, Pb, and Cd were 34.57%, 27.44%, 25.11%, and 23.11%, respectively. This suggests that the primary potential ecological risk elements in the study area are Hg and As, followed by Cd and Pb. Notably, toxic metals Hg and Pb, as well as As and Pb, exhibited significant positive correlations within the sampling area, suggesting a common source. An analysis of the relationship between soil physicochemical properties and toxic metals indicated that soil pH, SOM, TN, and TP were closely linked to toxic metal concentrations. The toxic metal elements in the research area's soil exhibit moderate variability (0.16 < CV < 0.36) to high variability (CV > 0.36). Within the range of 0–200 m, the CV values for Cd and Hg exceed 1, indicating a high level of variability. The coefficient of variation for SOM, TP, AP, AK and TK is relatively high with the of 2.93, 2.36, 2.36, 21.01, 7.54. The soil in the sampling area has undergone significant disturbances due to human activities, resulting in toxic metal pollution and nutrient deficiencies. [ABSTRACT FROM AUTHOR]

Scientific estimation and dynamic monitoring of CO2 emission trends are an important basis for formulating regional differentiated carbon reduction strategies. Using the integrated nighttime light data, this study estimated CO2 emissions in the Yellow River Basin (YRB) and Yangtze River Basin (YZRB) and discussed the similarities and differences of the spatial distribution of CO2 emissions for the two river basins. The results showed that: (1) The CO2 emissions in the two basins continued to rise, but the growth rate decreased from 2000 to 2018, showing an overall convergence trend, but have not yet reached carbon peak. (2) The high emission and high agglomeration areas were located in Shandong Province in the downstream of the YRB, Shanxi, Shaanxi and Inner Mongolia in the midstream and upstream, and the Yangtze River Delta (YRD). (3) Compared with the YRB, the growth rate of CO2 emissions in the YZRB is slower, and the growth rate declines greatly. In the YRB, it had higher CO2 emissions amount, wider area of high carbon emissions and more obvious spatial agglomeration than that in the YZRB. (4) According to CO2 emissions and economic development level, 220 cities of the two river basins were classified three types: low CO2–low development, high CO2–low development and high CO2–high development. [ABSTRACT FROM AUTHOR]

Agricultural technology adoption is an important way to improve agricultural technology and production efficiency and promote agricultural modernization. However, the low willingness to adopt agricultural technologies has been a challenge in China. Cognitive load may affect smallholder farmers' decision to adopt new technologies. Using an experimental economics approach, we examine the effect of cognitive load on smallholder farmers' willingness to adopt technology from a cognitive perspective based on a field experiment with 440 smallholder farmers in Shaanxi Province, China, in 2021 and 2022. The experimental results show that cognitive load has a significant negative effect on farmers' willingness to adopt technology, and the higher the level of cognitive load, the lower the farmers' willingness to adopt the technology. From the mechanism of action, cognitive load influences smallholder farmers' technology adoption intention by consuming their attention. In addition, cognitive ability, technology training, and government subsidies had heterogeneous effects on cognitive load affecting farmers' willingness to adopt new technologies, i.e., the cognitive load had less inhibitory effects on technology adoption willingness of smallholder farmers who has the high cognitive ability, participated in technology training and received government subsidies. Therefore, in the context of rural revitalization, the Chinese government should pay attention to the influence of farmers' cognitive mechanism on their willingness to adopt agricultural technologies, improve their cognitive ability, provide more technical training guidance, and provide targeted subsidies, to guide farmers to actively adopt new technologies and get rid of the "poverty trap". [ABSTRACT FROM AUTHOR]