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Abstract A quantitative research on the effect of coal mining on the soil organic carbon (SOC) pool at regional scale is beneficial to the scientific management of SOC pools in coal mining areas and the realization of coal low-carbon mining. Moreover, the spatial prediction model of SOC content suitable for coal mining subsidence area is a scientific problem that must be solved. Taking the Changhe River Basin of Jincheng City, Shanxi Province, China, as the study area, this paper proposed a radial basis function neural network model combined with the ordinary kriging method. The model includes topography and vegetation factors, which have large influence on soil properties in mining areas, as input parameters to predict the spatial distribution of SOC in the 0–20 and 2040 cm soil layers of the study area. And comparing the prediction effect with the direct kriging method, the results show that the mean error, the mean absolute error and the root mean square error between the predicted and measured values of SOC content predicted by the radial basis function neural network are lower than those obtained by the direct kriging method. Based on the fitting effect of the predicted and measured values, the R 2 obtained by the radial basis artificial neural network are 0.81, 0.70, respectively, higher than the value of 0.44 and 0.36 obtained by the direct kriging method. Therefore, the model combining the artificial neural network and kriging, and considering environmental factors can improve the prediction accuracy of the SOC content in mining areas.

Based on the 5615 working face of Beisu Coal Mine, a virtual prototype of the shearer cable drag system was developed using the MG2×70/325-BWD electric traction shearer as the carrier, in combination with CERO and ADAMS software. The shearer cable was equivalently modeled using the discrete rigid body method to study the dynamic characteristics of the drag system. This research provides a foundation for the design and optimization of both the cable and cable clamps. The results indicate that during the bending process of ordinary and reinforced cables in the cable drag system, the tensile force between the cable clamps increases from approximately 28 N and 37 N to a maximum value of 133 N and 146 N, respectively, before decreasing to around 57 N and 66 N. At the connection point between the drag system and the shearer, the tensile force between the cable clamps fluctuates and increases, reaching a maximum value of 925.2 N and 1134.7 N when the shearer reaches the end of the working face. These values are significantly lower than the cable clamp's breaking tensile strength of 70 kN, with peak values of 57.4 N and 94.1 N, respectively. During the cable bending process, The contact force with the cable clamp continuously changes with the bending angle, During 0 ~90°, the contact force between ordinary and reinforced cable and cable clamp gradually increases to the maximum values 61.3N and 86.2N, After 90 have plummeted to near 23 N and 25 N, In the process of dragging the cable to the top of the roller, it fluctuates between 45.2~51.7 N and 66.3~73.6 N respectively, Cable exit bends are slowly reduced to fluctuations around 16 N and 17 N, The tensile force between ordinary and reinforced discrete cables increased to around 58.4 N and 80.5 N and then decreased to around 12.6 N and 32.8 N, respectively. During the bending process of reinforced cables, the average contact force with the cable clamps increased by 22.3 N compared to the ordinary cables, while the average discrete tensile force between the cables increased by 18.7 N. Although the tensile and contact forces of the reinforced cable are slightly higher than those of the ordinary cable, the reinforced cable has a higher safety factor and greater adaptability. The drag motion of the cable is correlated with the characteristics of the ring-chain drive, and the drag speed and tensile force exhibit periodic variations due to the polygonal effect of the chain drive. The findings provide valuable insights for intelligent cable drag research and lay the foundation for the optimization of mining cables and cable clamps.

The hot-dry environment in high geothermal tunnels negatively affects the development of properties of cementitious materials. In order to improve the mechanical properties of cementitious materials in such environments, a proper curing system was developed, the material compositions were taken into account, and the related mechanism was analyzed by microscopic tests. The results showed that the mechanical properties and microstructure of cementitious materials can be improved effectively by adopting film curing and an adequate dosage of fly ash in a hot-dry environment. Compared with standard curing, a hot-dry environment accelerates the evaporation of water in fresh cementitious materials and the early hydration rate of cementitious materials, resulting in lots of unhydrated cement particles and an uneven distribution of hydration products, seriously decreasing the properties of the cementitious materials. Film curing keeps the water from evaporating and ensures enough water is available for hydration at an early age. The addition of FA reduces the amount of cement clinker and decreases hydration reaction rate in high temperature environments at an early stage, avoiding the unevenness of hydration products. High temperatures stimulate the pozzolanic activity of fly ash and promote the degree of secondary hydration reaction, producing more hydration products, as well as contributing to the improvement of the mechanical properties and microstructure of cementitious materials. In this study, in a hot-dry environment, the mechanical properties of mortar with 25% fly ash and 2–3 d film curing are better than those of other experimental groups, including those of standard curing.

Rapid urbanization has led to significant changes in land surface temperature (LST), which in turn affect the urban thermal environment effect and the health of residents. Exploring the causes of the urban thermal environment effect will provide guidance for promoting sustainable urban development. The spatiotemporal evolution of the urban thermal environment effect within the sixth ring road of Beijing was analyzed by inversion of remote sensing data to obtain the LST in 2004, 2009, 2014, and 2019. In addition, based on multivariate spatial data, we applied the standard deviation ellipse (SDE), spatial principal component analysis (PCA), and other methods to analyze and identify the relationships between the urban thermal environment effect and its influencing factors. The results show that from 2004 to 2019, the spatial distribution of urban development and LST within the sixth ring road of Beijing were closely related, the heat island area showed a small increasing trend, and differences in the thermal environment effect between different administrative regions in different periods were obvious. The main factors affecting the urban thermal environment effect were urban construction intensity, vegetation and water bodies, socioeconomic activities, and geomorphology. It is noteworthy that human factors had a greater impact than natural factors. Among them, the positive effect of the normalized difference impervious surface index (NDBBI) and the negative effect of the fractional vegetation cover (FVC) were the most prominent. This study provides theoretical support for mitigating the urban thermal environment effect and promoting sustainable urban development.

Rapid urbanization has triggered significant changes in urban land surface temperature (LST), which in turn affects urban ecosystems and the health of residents. Therefore, exploring the interrelationship between urban development and LST can help optimize the urban thermal environment and promote sustainable development. Based on remote sensing data from 2004–2019 within the sixth ring road of Beijing, this study investigates the spatiotemporal coupling law of night time light (NTL) and LST using an overall coupling model and analyzes the degree of coordination between them using a coordination model. The spatial response law between them was also analyzed using standard deviation ellipses and bivariate spatial autocorrelation. The results show that, from the perspective of spatiotemporal evolution, the spatial distributions of NTL and LST within the sixth ring road of Beijing were closely related from 2004 to 2019, although the overall coupling of NTL and LST was initially decreased and then continuously increased. From the perspective of coordination types, the main types of coordination between NTL and LST deteriorated over time. The increase in LST lagged behind NTL from 2004 to 2009 (heating hysteresis type), while LST increased ahead of NTL from 2014 to 2019 (heating advance type). This suggests that urban development became less efficient, while LST increases became more significant. In terms of correlation, NTL and LST showed significant positive correlation and spatial positive correlation; the correlation coefficient first decreased significantly and then continued to increase. From 2004 to 2009, the temperature increase caused by urbanization was suppressed due to the 2008 Beijing Olympics and related ecological protection policies, resulting in a significant decrease in the correlation coefficient between NTL and LST. From 2009 to 2019, short-term measures taken by Beijing during the Olympic Games were no longer effective, and the opposition between urban development and related policies made the policies increasingly less effective, thereby increasing the correlation coefficient between NTL and LST, and the increase in LST was more significant. This will greatly affect the urban ecological environment and residents’ health and make the previous government investment to suppress the temperature increase all in vain. This study can provide theoretical and practical support for the development of thermal environment optimization schemes and LST mitigation strategies in Beijing and other cities.

The farmland area in arid and semiarid regions accounts for about 40% of the total area of farmland in the world, and it continues to increase. It is critical for global food security to predict the crop yield in arid and semiarid regions. To improve the prediction of crop yields in arid and semiarid regions, we explored data assimilation-crop modeling strategies for estimating the yield of winter wheat under different water stress conditions across different growing areas. We incorporated leaf area index (LAI) and soil moisture derived from multi-source Sentinel data with the CERES-Wheat model using ensemble Kalman filter data assimilation. According to different water stress conditions, different data assimilation strategies were applied to estimate winter wheat yields in arid and semiarid areas. Sentinel data provided LAI and soil moisture data with higher frequency (2 m−2 and 0.0305 cm3 cm−3, respectively, for data assimilation-crop modeling. The temporal continuity of the CERES-Wheat model and the spatial continuity of the remote sensing images obtained from the Sentinel data were integrated using the assimilation method. The RMSE of LAI and soil water obtained by the assimilation method were lower than those simulated by the CERES-Wheat model, which were reduced by 0.4458 m2 m−2 and 0.0244 cm3 cm−3, respectively. Assimilation of LAI independently estimated yield with high precision and efficiency in irrigated areas for winter wheat, with RMSE and absolute relative error (ARE) of 427.57 kg ha−1 and 6.07%, respectively. However, in rain-fed areas of winter wheat under water stress, assimilating both LAI and soil moisture achieved the highest accuracy in estimating yield (RMSE = 424.75 kg ha−1, ARE = 9.55%) by modifying the growth and development of the canopy simultaneously and by promoting soil water balance. Sentinel data can provide high temporal and spatial resolution data for deriving LAI and soil moisture in the study area, thereby improving the estimation accuracy of the assimilation model at a regional scale. In the arid and semiarid region of the southeastern Loess Plateau, assimilation of LAI independently can obtain high-precision yield estimation of winter wheat in irrigated area, while it requires assimilating both LAI and soil moisture to achieve high-precision yield estimation in the rain-fed area.

Abstract Light conversion films are crucial for optimizing vegetable crop production in greenhouses, particularly during winter and spring seasons. This study investigated the effects of a europium-based light conversion film (RPO) compared to traditional polyolefin film (PO film, control) on cucumber (Cucumis sativus L.) cultivation, focusing on handle length, yield, and fruit quality in a randomized complete block design with three replications. Results demonstrated that RPO film significantly enhanced multiple light parameters: overall transmittance (8.5% increase), far-red radiation (710–760 nm, 17% increase), red-orange radiation (610–709 nm, 9.8% increase), and blue radiation (440–509 nm, 9.6% increase). The film also increased average light intensity (400–700 nm) by 13% and maximum temperature by 13%. Conversely, it reduced ultraviolet radiation (300–399 nm) by 38%, violet radiation (400–439 nm) by 3.3%, and green radiation (510–609 nm) by 5.7%. The modified light environment substantially improved cucumber production metrics. Handle length ratio decreased by 24% due to reduced cell numbers, while yield increased by 30%. Fruit quality parameters showed significant improvements: soluble protein (25% increase), vitamin C (27% increase), free amino acids (28% increase), and soluble solids (9% increase), with a 35% reduction in organic acid content. Notably, both auxin synthesis gene expression and auxin content in cucumber handles decreased by 87% and 24%, respectively.

Few studies have explored the impact of blue light-emitting diode (BL) irradiation combined with different storage temperatures on antioxidant defense and cell wall metabolic activities related to the quality deterioration of postharvest strawberries. This study investigates the effects of BL exposure as a non-chemical preservation strategy to improve the postharvest quality of strawberries stored at 22 °C and 8 °C. Over a 10-day storage period, BL irradiation significantly reduced respiratory and ethylene production rates, while preserving fruit firmness and increasing the contents of soluble sugar and total phenol at both temperatures. Additionally, increases of the enzymatic activities of antioxidant defense metabolism (e.g. superoxide dismutase (SOD) and peroxidase (POD)) accompanied with decreased levels of reactive oxygen species (ROS) (e.g. superoxide anion (O2−), and hydrogen peroxide (H2O2)) and the content of secondary metabolites (e.g. ascorbic acid (AsA)) accompanied with enhanced activities of ascorbate peroxidase (APX) and glutathione reductase (GR) were found in BL irradiated postharvest strawberries at the later stages of storage. Meanwhile, BL irradiation also mitigated the activity of cell wall-degrading enzymes, thereby reducing the degradation rates of protopectin (PP), cellulose (CEL), and hemicellulose (HCEL), while maintaining the structural integrity of cell walls. According to fuzzy mathematics analysis, the membership function values for BL irradiated postharvest strawberries at different storage temperatures ranked as follows: BL + 8 °C (0.60) > BL + 22 °C (0.52) > 8 °C (0.46) > 22 °C (0.36). These findings suggest that BL irradiation not only extends the shelf life of strawberries by modulating antioxidant defense and cell wall metabolic activities but also maintains their commercial quality, particularly under low-temperature storage conditions. Therefore, BL irradiation holds significant promise for minimizing quality deterioration in postharvest strawberries during cold storage.

Continuous cropping has emerged as a significant challenge affecting yield and quality in greenhouse strawberries, particularly as the cultivation of strawberries as a protected crop continues to increase. To address this issue, substrates with 0 or 2 years of continuous cropping were fertilized with two types of organic materials: vermicompost derived from either sludge or cattle manure. A control group consisted of substrate without the addition of vermicompost. Both type of vermicompost improved substrate fertility, promoted plant growth and fruit quality. The cattle manure vermicompost had a better improvement effect at peak fruiting stage. Substrate nutrients were increased 14.58~38.52% (0-year substrate) and 12.04%~42.54% (2-year substrate), respectively. In both substrate types, there was a substantial increase in microbial population and enzyme activity, accompanied by a significant decrease in phenolic acid content. During the senescence stage, the use of cattle manure vermicompost led to enhancements in plant height, leaf area, and root length, with increases ranging from 15.01% to 32.77% and 23.75% to 32.78% across the two substrate types compared to the control group. Furthermore, the application of cattle manure vermicompost significantly improved both fruit yield and quality. Compared with the control (CK), the cattle manure vermicompost increased fruit yield by 18.29% and 19.64% in the 0- and 2-year substrates, respectively. The contents of soluble sugars, vitamin C, and free amino acids in the fruits increased by 21.42%~34.16% (0-year substrate) and 9.62%~42.62% (2-year substrate), at peak fruiting stage. Cattle manure vermicompost application to the 2-year substrate ranked higher in the membership function than the CK treatment at 0-year planting. In conclusion, the application of vermicompost can significantly improve strawberry fruit yield and quality, as well as substrate characteristics, thus effectively addressing challenges associated with continuous cropping. Furthermore, the use of cattle manure vermicompost produced more pronounced positive effects.

Aldolase exhibits multiple functions in a variety of organisms, including fungi, unicellular algae and plants, and so on. Furthermore, different isoforms of fructose 1,6-bisphosphate aldolase (FBA) exhibit significantly different characteristics and functions. This review describes the structures, characteristics, and functions of FBAs derived from diverse organisms, including FBA II in pathogen microorganisms, as well as FBA I mainly in unicellular algae and plants. Differences between FBA and FBP aldolase-phosphatase bifunctional enzyme (FBA/P) are also discussed. Finally, we suggest several potential research questions regarding the functions of FBA in higher plants.

The objective of this study was to investigate the changes of microbial communities in different treatment units of a full-scale wastewater treatment plant (WWTP) equipped with a serially combined rotating biological contactor (RBC) and anaerobic-anoxic-oxic-oxic (A²/O²) processes. Highthroughput sequencing results showed that functional communities including Methylotenera, Nitrospiraceae, Terrimonas, Zoogloea, Lysobacter, and Rhodobacter were the most dominant communities in the treatment system. The sequencing results demonstrated that the microbial communities along the different treatment units showed distinct community profiles. Additionally, dominant functional communities with Methylotenera and Methanolobus were significantly enriched on RBC films compared to those in the activated sludge of the RBC treatment unit, indicating that the RBC plays essential functions in the WWTP. In general, thoroughly screening the microbial communities in WWTP equipped with RBC and A²/O² and monitoring the changes over seasons contributed to maintain and adjust the wastewater treatment system in case of decayed treatment efficiencies. Besides, our work could guide us to rapidly set up a new similar WWTP. [ABSTRACT FROM AUTHOR]