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Rice fields are an important source of nitrous oxide (NO), where rice plants could act as a key factor controlling NO fluxes during the flooding-drying process; however, the microbial driving mechanisms are unclear. In this study, specially designed equipment was used to grow rice plants and collect emitted NO from the root-growing zone (zone A), root-free zones (zones B, C, and D) independently, at tillering and booting stages under flooding and drying conditions. Soil samples from the four zones were also taken separately. Nitrifying and denitrifying community abundances were detected using quantitative polymerase chain reaction (qPCR). The NO emission increased significantly along with drying, but the NO emission capabilities varied among the four zones under drying, while zone B possessed the highest NO fluxes that were 2.7~4.5 times higher than those from zones C and D. However, zone A showed NO consumption potential. Notably, zone B also harbored the highest numbers of narG-containing denitrifiers and amoA-containing nitrifiers under drying at both tillering and booting stages. This study demonstrates that drying caused significant increase in NO emission from rhizosphere soil, in which the higher abundance of AOB would help to produce more nitrate and significantly higher narG-containing microbes would drive more NO production and emission. [ABSTRACT FROM AUTHOR]

As part of a long-term sloped land use experiment established in 1995 at Taoyuan Agro-ecosystem Research Station (111°26′ E, 28°55′ N) in China, soil samples were collected from three land use types, including cropland (CL), natural forest, and tea plantation. Quantitative polymerase chain reaction and terminal restriction fragment length polymorphism were used to determine the abundance and community composition of amoA-containing bacteria (AOB) and archaea (AOA). The results indicate that land use type induced significant changes in soil potential nitrification rate and community composition, diversity, and abundance of AOB and AOA. Both AOB and AOA community compositions were generally similar between upper and lower slope positions (UP and LP), except within CL. The LP soils had significantly ( p < 0.05) higher diversity and abundance of both AOB and AOA than in the UP. Potential nitrification rate was significantly correlated ( p < 0.05) with diversity and abundance of AOA, but not with AOB. Among land use types, the NO and amoA-containing AOA runoff loss was greatest in CL. Nitrate-N runoff loss was significantly correlated ( p < 0.05) with the loss of AOA amoA copies in the runoff water. Furthermore, relationships between NO-N runoff loss and abundance of AOA but not of AOB at both slope positions were significantly correlated ( p < 0.05). These findings suggest that AOA are more important than AOB in nitrification and NO-N runoff loss in acidic soils across sloped land use types. [ABSTRACT FROM AUTHOR]

Globally, Parkinson's disease (PD) is one of the common neurodegenerative diseases in the elderly with increasing morbidity and disability, and its clinical pathogenesis is not clear. To compare the differences in disease severity and blood biomarkers levels and their correlation between patients with early-onset Parkinson's disease (EOPD) and late-onset Parkinson's disease (LOPD). A total of 342 patients diagnosed with PD were retrospectively collected. PD patients were categorized into EOPD (24 patients) and LOPD (318 patients) according to the age of onset of the disease. The Hoehn-Yahr (HY) staging was used to assess the severity of the disease in PD patients. Subjective rating scales such as the Mini-mental State Examination (MMSE) were used to assess the motor and non-motor functions of the patients. The differences of objective blood biomarkers such as triglyceride (TG) between the two groups were investigated. The correlation between them and PD was explored by logistic analysis. Percentage of EOPD group with HY staged as intermediate to late and Scales for Outcomes in Parkinson's Disease-Autonomic (SCOPA-AUT), Movement Disorder Society-Unified Parkinson's disease Rating Scale-III (MDS-UPDRS-III), Montreal Cognitive Assessment (MoCA) score and TG, non-high-density lipoprotein-cholesterol (N-HDL-C), homocysteine (HCY), apolipoprotein B (Apo-B), free triiodothyronine (FT3), free thyroxine (FT4), high-sensitivity C-reactive protein (hs-CRP) levels were lower than those in the LOPD group (P < 0.05); and the proportion of HY staged as early stage, Hamilton Anxiety Scale (HAMA) and Fatigue severity scale (FSS) scores and the levels of vitamin B12 were higher than those in the LOPD group (P < 0.05). The results of Multifactorial Logistic regression analysis showed that N-HDL-C [OR = 1.409, 95 % CI (1.063, 1.868)], Apo-B [OR = 0.797, 95 % CI (0.638, 0.997)], Vitamin B12 [OR = 0.992, 95 % CI (0.987, 0.998)] and hs-CRP [OR = 1.124, 95 % CI (1.070, 1.182)] were independent factors affecting the severity of PD, with significant differences between groups (P < 0.05). N-HDL-C, Apo-B, Vitamin B12, and hs-CRP levels play an important role in the progression of PD. [ABSTRACT FROM AUTHOR]

Background and Aims: Abandonment of paddy fields is a significant threat to soil organic carbon (SOC) stocks owing to the associated shift from anaerobic to aerobic conditions. However, the impact of this transition on the dynamics of soil total nitrogen (TN) and its relationship with SOC in bulk soil and soil aggregates remains unclear.A long-term experiment was conducted to examine abandoned paddy fields with different fertilizer treatments over a 16-year period before abandonment, followed by an 8-year period after abandonment.The abandonment of paddy fields led to a significant decrease in TN content by an average of 14.0%, resulting in a mean annual loss rate of 0.08 t N ha−1. The loss of TN was as sensitive as that of SOC, and there was a positive correlation between SOC and TN in both bulk soil and soil aggregates. The loss of SOC and TN was mainly caused by reductions in the middle- and micro-aggregate-associated SOC and TN, which together explained approximately 87.3% of C loss and 81.3% of N loss. The weaker protective capacity of soil aggregates (> 53 μm) was evidenced by a significant decrease in aggregate-associated C (average of 8.7%) and N (average of 9.1%). Abandonment maintained stoichiometric stability, with bulk soil C:N ratios ranging from 9.4 to 9.6 following abandonment.Paddy soil aggregate-associated SOC and TN were sensitive to loss owing to the weaker protective capacity of soil aggregates following the abandonment of paddy fields. The C:N ratios remained relatively consistent after abandonment.Methods: Abandonment of paddy fields is a significant threat to soil organic carbon (SOC) stocks owing to the associated shift from anaerobic to aerobic conditions. However, the impact of this transition on the dynamics of soil total nitrogen (TN) and its relationship with SOC in bulk soil and soil aggregates remains unclear.A long-term experiment was conducted to examine abandoned paddy fields with different fertilizer treatments over a 16-year period before abandonment, followed by an 8-year period after abandonment.The abandonment of paddy fields led to a significant decrease in TN content by an average of 14.0%, resulting in a mean annual loss rate of 0.08 t N ha−1. The loss of TN was as sensitive as that of SOC, and there was a positive correlation between SOC and TN in both bulk soil and soil aggregates. The loss of SOC and TN was mainly caused by reductions in the middle- and micro-aggregate-associated SOC and TN, which together explained approximately 87.3% of C loss and 81.3% of N loss. The weaker protective capacity of soil aggregates (> 53 μm) was evidenced by a significant decrease in aggregate-associated C (average of 8.7%) and N (average of 9.1%). Abandonment maintained stoichiometric stability, with bulk soil C:N ratios ranging from 9.4 to 9.6 following abandonment.Paddy soil aggregate-associated SOC and TN were sensitive to loss owing to the weaker protective capacity of soil aggregates following the abandonment of paddy fields. The C:N ratios remained relatively consistent after abandonment.Results: Abandonment of paddy fields is a significant threat to soil organic carbon (SOC) stocks owing to the associated shift from anaerobic to aerobic conditions. However, the impact of this transition on the dynamics of soil total nitrogen (TN) and its relationship with SOC in bulk soil and soil aggregates remains unclear.A long-term experiment was conducted to examine abandoned paddy fields with different fertilizer treatments over a 16-year period before abandonment, followed by an 8-year period after abandonment.The abandonment of paddy fields led to a significant decrease in TN content by an average of 14.0%, resulting in a mean annual loss rate of 0.08 t N ha−1. The loss of TN was as sensitive as that of SOC, and there was a positive correlation between SOC and TN in both bulk soil and soil aggregates. The loss of SOC and TN was mainly caused by reductions in the middle- and micro-aggregate-associated SOC and TN, which together explained approximately 87.3% of C loss and 81.3% of N loss. The weaker protective capacity of soil aggregates (> 53 μm) was evidenced by a significant decrease in aggregate-associated C (average of 8.7%) and N (average of 9.1%). Abandonment maintained stoichiometric stability, with bulk soil C:N ratios ranging from 9.4 to 9.6 following abandonment.Paddy soil aggregate-associated SOC and TN were sensitive to loss owing to the weaker protective capacity of soil aggregates following the abandonment of paddy fields. The C:N ratios remained relatively consistent after abandonment.Conclusions: Abandonment of paddy fields is a significant threat to soil organic carbon (SOC) stocks owing to the associated shift from anaerobic to aerobic conditions. However, the impact of this transition on the dynamics of soil total nitrogen (TN) and its relationship with SOC in bulk soil and soil aggregates remains unclear.A long-term experiment was conducted to examine abandoned paddy fields with different fertilizer treatments over a 16-year period before abandonment, followed by an 8-year period after abandonment.The abandonment of paddy fields led to a significant decrease in TN content by an average of 14.0%, resulting in a mean annual loss rate of 0.08 t N ha−1. The loss of TN was as sensitive as that of SOC, and there was a positive correlation between SOC and TN in both bulk soil and soil aggregates. The loss of SOC and TN was mainly caused by reductions in the middle- and micro-aggregate-associated SOC and TN, which together explained approximately 87.3% of C loss and 81.3% of N loss. The weaker protective capacity of soil aggregates (> 53 μm) was evidenced by a significant decrease in aggregate-associated C (average of 8.7%) and N (average of 9.1%). Abandonment maintained stoichiometric stability, with bulk soil C:N ratios ranging from 9.4 to 9.6 following abandonment.Paddy soil aggregate-associated SOC and TN were sensitive to loss owing to the weaker protective capacity of soil aggregates following the abandonment of paddy fields. The C:N ratios remained relatively consistent after abandonment. [ABSTRACT FROM AUTHOR]

Biological nitrogen (N2) fixation as a source of new N input into the soil by free-living diazotrophs is important for achieving sustainable rice agriculture. However, the dominant environmental drivers or factors influencing N2 fixation and the functional significance of the diazotroph community structure in paddy soil across a climatic gradient are not yet well understood. Thus, we characterized the diazotroph community and identified the ecological predictors of N2 fixation potential in four different climate zones (mid-temperate, warm-temperate, subtropical, and tropical paddy soils) in eastern China. Comprehensive nifH gene sequencing, functional activity detection, and correlation analysis with environmental factors were estimated. The potential nitrogenase activity (PNA) was highest in warm-temperate regions, where it was 6.2-, 2.9-, and 2.2-fold greater than in the tropical, subtropical, and mid-temperate regions, respectively; nifH gene abundance was significantly higher in warm-temperate and subtropical zones than in the tropical or mid-temperate zones. Diazotroph diversity was significantly higher in the tropical climate zone and significantly lower in the mid-temperate zone. Non-metric multidimensional scaling and canonical correlation analysis indicated that paddy soil diazotroph populations differed significantly among the four climate zones, mainly owing to differences in climate and soil pH. Structural equation models and automatic linear models revealed that climate and nutrients indirectly affected PNA by affecting soil pH and diazotroph community, respectively, while diazotroph community, C/P, and nifH gene abundance directly affected PNA. And C/P ratio, pH, and the diazotroph community structure were the main predictors of PNA in paddy soils. Collectively, the differences in diazotroph community structure have ecological significance, with important implications for the prediction of soil N2-fixing functions under climate change scenarios. [ABSTRACT FROM AUTHOR]

• A framework-reinforced orderly-woven superhydrophobic metal spiral coil-carbon fibers composite with a durable, uniform micro-structure was prepared. • An emulsion separation model has been established via CFD, which revealed the dynamic trajectory and volume change of water droplets in real-time. • The prepared metal–carbon composites still showed reliable separation purity and stable flux for several industrial lubricating oil emulsions in harsh environments. The primary barrier to the widespread use of super-wetting materials is the surface's limited resistance to physical damage, which leads to poor mechanical qualities. In this study, framework-reinforced orderly-woven superhydrophobic metal spiral coil-carbon fibers composites (SMSC-CFsC) with a durable uniform micro-structure were prepared by nested carbon fibers into metal spiral coils cleverly and woven them into a three-dimensional porous material innovatively. The separation purity of the prepared metal–carbon composites on several commonly used industrial lubricating oil emulsions was better than 99.90 % and the flux was greater than 1000 L/m2h. More significantly, computational fluid dynamics was used to establish a simulation model for emulsion separation that revealed the real-time dynamic motion trajectory and volume changes of water droplets. Additionally, even after high-temperature, compression, wear, and corrosion experiments, it still showed dependable separation purity and stable flux. As a result, it has been demonstrated that the proposed metal–carbon composite has a long oil–water separation service life in harsh environments and has great potential for developing efficient and durable emulsion separation materials. [ABSTRACT FROM AUTHOR]

• Bacterial communities in different types of agricultural and nonagricultural soils were studied. • Soil type have strong selective pressure on bacterial community in agricultural soils. • Some core taxa can achieve large abundances in response to long-term crop cultivation. • A large pool of specific taxa with low abundance are restricted to specific soil type. Parent materials are crucial in soil formation and development, but their importance in shaping soil bacterial communities after thousands of years of soil formation remains unknown, especially in agricultural soils. To resolve the influence of underlying features inherited from parent materials on soil microbiome, the microbial community in 197 agricultural soils with long-term crop cultivation history and nonagricultural reference soils from four major types of soils in China, i.e., quaternary red clay soils, tertiary red sandstone soils, alluvial soils and black soils, were analyzed and compared. We found that different types of soils supported distinct bacterial communities. The characteristics inherited from parent materials explained more of the variation (31.47%) in bacterial community structure than the selected variables regulated by soil management (1.63%) and the climate condition (1.10%). Only 9.0% of total bacterial amplicon sequence variants (ASVs) which contributed, on average, 47% of the total bacterial abundances in a given agricultural soil, were shared by all soil types. These abundant common ASVs were closely related to agricultural practices, suggesting a strong enrichment effect of a small number of core taxa by long-term crop cultivation. In contrast, approximately 55.6% of ASVs with low relative abundance were specific to soil type. These specific groups were closely associated with the distinctive features of soil type, implying that they represent unique populations selected by the parent material features during pedogenesis. Collectively, soil type may have a strong selective pressure on the bacterial communities in matured agricultural soils, leading to a large pool of specific taxa with limited environmental occurrence. Whilst a small number of core taxa achieve high abundances by responding to long-term crop cultivation. [ABSTRACT FROM AUTHOR]

The porosity of oil-impregnated porous polyimide is closely related to its tribological and mechanical properties, which is critical to determine the application and service life. Herein, polyimides with different porosities are fabricated by mixing different contents of pore-forming agent to investigate the significance of porosity with dimethyl silicone oil as impregnated lubricant. The dynamic porosity was simulated to explain the self-lubricating mechanism. Results show that the increasing porosity results in a higher oil content and the oil can be easily extruded, but leads to a poor bearing capacity and a higher friction coefficient, and vice versa. The friction coefficient reduced by 46.15% with the optimized porosity of 20.05%. This study may provide guidance for the development of high-performance oil-impregnated polymers. • The oil-impregnated porous polyimide (OPPI) has excellent self-lubricating property. • The porosity of OPPI is crucial to its tribological and mechanical properties. • The dynamic porosity was calculated to explain the lubricating mechanism of OPPI. [ABSTRACT FROM AUTHOR]

Purpose: The incidence of vascular dementia (VaD), as one of the main types of dementia in old age, has been increasing year by year, and exploring its pathogenesis and seeking practical and effective treatment methods are undoubtedly the key to solving this problem. Phosphoglycerate translocase 5 (PGAM5), as a crossroads of multiple signaling pathways, can lead to mitochondrial fission, which in turn triggers the onset and development of necroptosis, and thus PGAM5 may be a novel target for the prevention and treatment of vascular dementia., Methods: Animal model of vascular dementia was established by Two-vessel occlusion (2-VO) method, and cellular model of vascular dementia was established by oxygen glucose deprivation (OGD) method. Neuronal damage was detected in vivo and in vitro in different groups using different concentrations of the PGAM5-specific inhibitor LFHP-1c, and necroptosis and mitochondrial dynamics-related factors were determined., Results: In vivo experiments, 10 mg/kg -1 and 20 mg/kg -1 LFHP-1c improved cognitive deficits, reduced neuronal edema and vacuoles, increased the number of nissl bodies, and it could modulate the expression of Caspase family and Bcl-2 family related proteins and mRNAs and ameliorate neuronal damage. Simultaneously, in vitro experiments, 5 μM, 10 μM and 20 μM LFHP-1c increased the activity and migration number of model cells, reduced the number of apoptotic cells, ameliorated the excessive accumulation of intracellular reactive oxygen species, inhibited the over-activation of caspase-family and Bcl-2-family related proteins and mRNAs, and improved the mitochondrial dynamics of the fission and fusion states. Moreover, in vivo and in vitro experiments have shown that LFHP-1c can also upregulate the expression level of BDNF, inhibit the expression content of TNF-α and ROS, regulate the expression of proteins and mRNAs related to the RIPK1/RIPK3/MLKL pathway and mitochondrial dynamics, and reduce neuronal apoptosis., Conclusions: Inhibition of PGAM5 expression level can reduce neuronal damage caused by chronic cerebral ischemia and hypoxia, which mainly prevents necroptosis by targeting the RIPK1/RIPK3/MLKL signaling pathway and regulates the downstream mitochondrial dynamics homeostasis system to prevent excessive mitochondrial fission, thus improving cognition and exerting cerebroprotective effects., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Both natural revegetation and cropping have great impact on long-term soil carbon (C) sequestration, yet the differences in their underlying mechanisms remain unclear. In this study, we investigated trends in soil organic C (SOC) accumulation during natural revegetation (VR) and cropping processes over 24 years, and explored the contributions of microbial necromass and plant-derived C to SOC formation and their primary controls. Over the course of 24 years of land use/cover change (LUCC) from 1995, SOC content exhibited a more substantial increase in VR (0.31 g kg -1  a -1 ) than in cropland (0.14 g kg -1  a -1 ) during Stage II (>10 y after LUCC), and recalcitrant organic carbon explained more of the SOC variation than easily oxidizable carbon. The higher SOC content in VR was attributed to a greater contribution of plant-derived C (14-28 %) than that in cropland (3-11 %) to SOC and a consistently lower ratio of cinnamyl (C)- to vanillyl (V)-type phenols in VR across all the assessed years. Although there were higher proportion of microbial necromass of SOC (41-84 %) in cropland than in VR, the differences were not significant. The dominant bacterial phylum of Chloroflexi and soil nitrogen content were the primary biotic and abiotic factors regulating microbial-derived and plant-derived C in both cropland and VR. However, soil phosphorus content was the main factor in cropland, while climatic factors such as mean annual precipitation were more important in VR. These results provided evidence that long-term natural revegetation enhanced SOC sequestration by greater contribution of plant-derived C to SOC formation compared to cropping. These findings underscore the synergistic contribution of vegetation and microorganisms to long-term SOC sequestration, offering insights into the different mechanisms of carbon formation during VR and cropping processes, and providing support for optimizing land management to achieve global carbon neutrality goals., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Hongling Qin reports financial support was provided by the National Ecosystem Science Data Center. Baoli Zhu reports financial support was provided by the National Key Research and Development Program of China. Baoli Zhu reports financial support was provided by Hunan Science Fund for Distinguished Young Scholars. Hongling Qin reports was provided by the Natural Science Foundation of Hunan. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

As ionic liquids (ILs) continue to be prepared, there is a growing need to develop theoretical methods for predicting the properties of ILs, such as gas solubility. In this work, different strategies were employed to obtain the solubility of CO 2 and N 2 , where a conductor-like screening model for real solvents (COSMO-RS) was used as the basis. First, experimental data on the solubility of CO 2 and N 2 in ILs were collected. Then, the solubility of CO 2 and N 2 in ILs was predicted using COSMO-RS based on the structures of cations, anions, and gases. To further improve the performance of COSMO-RS, two options were used, i.e., the polynomial expression to correct the COSMO-RS results and the combination of COSMO-RS and machine learning algorithms (eXtreme Gradient Boosting, XGBoost) to develop a hybrid model. The results show that the COSMO-RS with correction can significantly improve the prediction of CO 2 solubility, and the corresponding average absolute relative deviation (AARD) is decreased from 43.4% to 11.9%. In contrast, such an option cannot improve that of the N 2 dataset. Instead, the results obtained from coupling machine learning algorithms with the COSMO-RS model agree well with the experimental results, with an AARD of 0.94% for the solubility of CO 2 and an average absolute deviation (AAD) of 0.15% for the solubility of N 2 ., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Qin, Wang, Ma, Li, Liu and Ji.)

In this study, a porous structure for a porous liquid storage medium is generated, and the homogenization theory based on displacement boundary conditions is used to predict the effective mechanical properties. The relationship between the porous material's macroscopic mechanical properties and microstructure is next analyzed. In order to establish the relationship between the microstructure of porous materials and their macroscopic mechanical properties, assuming that the pores grow along the z direction, a method is proposed to generate 3D open-cell porous materials based on six design parameters (i.e., the number of pores, porosity, irregularity of pore distribution, the randomness of pore growth in the x and y directions, and randomness of pore size). Since the porosity of oil-bearing materials ranges from 20 to 30%, the porosity of the RVE (Representative Volume Element) was kept under control at about 25%, and the effect of the six design factors on the mechanical properties of the RVE was investigated. Utilizing SLA 3D printing technology, specimens were produced, and compression tests were used to show how useful the results of the numerical analysis were. The results demonstrated that after the number of RVE pores reaches 9, the numerical results have good repeatability. The irregularity of the initial pore distribution has little effect on the effective mechanical properties of the RVE. At the same time, the increase in the randomness of pore growth and the randomness of pore size increases the degree of weakening of the mechanical properties in the z-direction, while reducing the degree of weakening in the x and y directions, but the latter has a smaller impact. Furthermore, there is a superimposition effect of design parameters on the RVE., (© 2023. Springer Nature Limited.)

Objective: To explore the clinical efficacy of Zhuang Medicine Lotus Acupuncture Cupping Stasis Therapy on patients with postherpetic neuralgia (PHN) and its action mechanism., Methods: 36 patients are randomly divided into Lotus Acupuncture Cupping Stasis Therapy group, pure cupping group and gabapentin group, with a total of five observation points for the first, fifth, tenth, fifteenth, and twentieth sessions of therapy (one session every three days). At each observation point, the venous blood of the patients is taken, and the contents of and changes in WNT3a, Frizzled8, β-catenin, IL-18, TNF-α, NR2B, NK-1 and SP are tested by ELISA, RT-PCR and WesternBlot, respectively. The VAS scores and safety of the patients in the three groups are compared., Results: With increased time spent in therapy, the VAS scores of patients in each group decreased gradually and there was a significant reduction in pain in patients in the Lotus Acupuncture Cupping Stasis Therapy group compared to the gabapentin and pure cupping groups (P<0.05). The levels of IL-18, TNF-α, NK-1, SP, WNT3a, Frizzled 8 and β-catenin in the serum of all patients experienced a constant decline over time (P<0.05); the levels of the aforesaid factors in the serum of patients in the Lotus Acupuncture Cupping Stasis Therapy group dropped remarkably after the tenth session of therapy compared to those in gabapentin and pure cupping groups (P<0.05)., Conclusions: Zhuang Medicine Lotus Acupuncture Cupping Stasis Therapy can significantly reduce the pain of PHN patients, with a good therapeutic effect, and it is worthy of clinical use., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Rising temperature affects microbial composition and function in agriculture field, especially under nitrogen fertilization. In this study, we investigated the bacterial community of paddy soil incubated at controlled temperatures (5 °C, 15 °C, 25 °C, and 35 °C). Results showed that the response of bacterial communities to temperature was not uniform. Temperature elevation from 15 to 25 °C abruptly shifted the soil bacterial community, whereas elevation from 5 to 15 °C and from 25 to 35 °C had a marginal effect. The bacterial α-diversity was higher at 5 °C and 15 °C, owing to the massively distributed taxa with low abundance. However, as the temperature increased to 25 °C and 35 °C, these taxa were diminished, whereas Firmicutes significantly increased, resulting in a strong decline in α-diversity. Simultaneously, bacterial network complexity significantly increased at 25 °C and 35 °C, indicating the bacteria had closer interactions. Nitrogen application aggravated the variation in bacterial diversity and network complexity among temperatures. Interestingly, most complex network was observed under higher temperatures in fertilized soils. Collectively, these results indicate that nitrogen exacerbates the response of the soil bacterial community to temperature, and association between diversity and network complexity may be present., (© 2022. The Author(s).)

Fungal denitrifiers play important roles in soil nitrogen cycling, but we have very limited knowledge about their distribution and functions in ecosystems. In this study, three types of arable soils were collected across different climate zones in China, including quaternary red clay soils, alluvial soils, and black soils. The composition and abundance of fungal nirK -containing denitrifiers was determined by MiSeq high-throughput sequencing and qPCR, respectively. Furthermore, a substrate-induced inhibition approach was used to explore N 2 O emissions from fungal denitrification. The results showed that the arable soils contained a wide range of nirK -containing fungal denitrifiers, with four orders and eight genera. Additionally, approximately 57.30% of operational taxonomic unit (OTUs) belonged to unclassified nirK -containing fungi. Hypocreales was the most predominant order, with approximately 40.51% of the total number of OTUs, followed by Sordariales, Eurotiales, and Mucorales. It was further indicated that 53% of fungal nirK OTUs were shared by the three types of soils (common), and this group of fungi comprised about 98% of the total relative abundance of the nirK -containing population, indicating that the distribution of fungal nirK -containing denitrifiers was quite homogenous among the soil types. These common OTUs were determined by multiple soil characteristics, while the composition of unique OTUs was manipulated by the specific properties of each soil type. Furthermore, fungal N 2 O emissions were significantly and positively correlated with fungal nirK abundance in the soils, whereas it was not clearly related to fungal nirK compositions. In conclusion, although the arable soils hosted diverse nirK -containing fungal denitrifiers, fungal nirK compositions were highly homogenous among the soil types, which could be a consequence of enduring agricultural practices. The abundance of fungal nirK -containing denitrifiers, rather than their composition, may play more significant roles in relation to N 2 O emission from fungal denitrification.

Rice fields are an important source of nitrous oxide (N 2 O), where rice plants could act as a key factor controlling N 2 O fluxes during the flooding-drying process; however, the microbial driving mechanisms are unclear. In this study, specially designed equipment was used to grow rice plants and collect emitted N 2 O from the root-growing zone (zone A), root-free zones (zones B, C, and D) independently, at tillering and booting stages under flooding and drying conditions. Soil samples from the four zones were also taken separately. Nitrifying and denitrifying community abundances were detected using quantitative polymerase chain reaction (qPCR). The N 2 O emission increased significantly along with drying, but the N 2 O emission capabilities varied among the four zones under drying, while zone B possessed the highest N 2 O fluxes that were 2.7~4.5 times higher than those from zones C and D. However, zone A showed N 2 O consumption potential. Notably, zone B also harbored the highest numbers of narG-containing denitrifiers and amoA-containing nitrifiers under drying at both tillering and booting stages. This study demonstrates that drying caused significant increase in N 2 O emission from rhizosphere soil, in which the higher abundance of AOB would help to produce more nitrate and significantly higher narG-containing microbes would drive more N 2 O production and emission.

Field investigation, laboratory analysis and wind tunnel simulation showed that in Wuchuan County of Inner Mongolia, low precipitation, frequent and high wind velocity, coarse soil texture, and thawing and freezing were the main causes of soil wind erosion happened very easily in spring. In late winter and early spring, the vegetation coverage was in order of shrub-land>natural grassland>rainfed farmland, and thus, increasing the surface cover of rainfed farmland should be an urgent need to control the wind erosion in Wuchuan County. The soil wind erosion rate decreased exponentially with increasing soil moisture content, and 6% soil moisture content was a turning point from severe to light. The topsoil moisture content under different land use patterns was in order of natural grassland> rainfed farmland >shrub-land. With increasing wind velocity, soil wind erosion rate increased by power function, and 18 m x s(-1) wind velocity was a switching point to aggravate the wind erosion.