How does atmospheric pressure cold helium plasma affect the biomechanical behaviour on alkali-lesioned corneas?

BACKGROUND: Melting corneal ulcers are a serious condition that affects a great number of animals and people around the world and it is characterised by a progressive weakening of the tissue leading to possible severe ophthalmic complications, such as visual impairment or blindness. This disease is routinely treated with medical therapy and keratoplasty, and recently also with alternative regenerative therapies, such as cross-linking, amniotic membrane transplant, and laser. Plasma medicine is another recent example of regenerative treatment that showed promising results in reducing the microbial load of corneal tissue together with maintaining its cellular vitality. Since the effect of helium plasma application on corneal mechanical viscoelasticity has not yet been investigated, the aim of this study is first to evaluate it on ex vivo porcine corneas for different exposition times and then to compare the results with previous data on cross-linking treatment. RESULTS: 94 ex vivo porcine corneas divided into 16 populations (healthy or injured, fresh or cultured and treated or not with plasma or cross-linking) were analysed. For each population, a biomechanical analysis was performed by uniaxial stress-relaxation tests, and a statistical analysis was carried out considering the characteristic mechanical parameters. In terms of equilibrium normalised stress, no statistically significant difference resulted when the healthy corneas were compared with lesioned plasma-treated ones, independently of treatment time, contrary to what was obtained about the cross-linking treated corneas which exhibited more intense relaxation phenomena. CONCLUSIONS: In this study, the influence of the Helium plasma treatment was observed on the viscoelasticity of porcine corneas ex vivo, by restoring in lesioned tissue a degree of relaxation similar to the one of the native tissue, even after only 2 min of application. Therefore, the obtained results suggest that plasma treatment is a promising new regenerative ophthalmic therapy for melting corneal ulcers, laying the groundwork for further studies to correlate the mechanical findings with corneal histology and ultrastructural anatomy after plasma treatment.

Effect of Arbuscular Mycorrhizal Fungi (AMF) on photosynthetic characteristics of cotton seedlings under saline-alkali stress.

The study aimed to find the best Arbuscular Mycorrhizal Fungi (AMF) strain for cotton growth in Xinjiang's salinity and alkali conditions. Cotton (Xinluzao 45) was treated with Funneliformis mosseae (GM), Rhizophagus irregularis (GI), and Claroideoglomus etunicatum (GE) as treatments, while untreated cotton served as the control (CK). Salinity stress was applied post-3-leaf stage in cotton. The study analyzed cotton's reactions to diverse saline-alkali stresses, focusing on nutrient processes and metabolism. By analyzing the growth and photosynthetic characteristics of plants inoculated with Funneliformis mosseae to evaluate its salt tolerance. Saline-alkali stress reduced chlorophyll and hindered photosynthesis, hampering cotton growth. However, AMF inoculation mitigated these effects, enhancing photosynthetic rates, CO2 concentration, transpiration, energy use efficiency, and overall cotton growth under similar stress levels. GM and GE treatments yielded similar positive effects. AMF inoculation enhanced cotton plant height and biomass. In GM treatment, cotton exhibited notably higher root length than other treatments, showing superior growth under various conditions. In summary, GM-treated cotton had the highest infection rate, followed by GE-treated cotton, with GI-treated cotton having the lowest rate (GM averaging 0.95). Cotton inoculated with Funneliformis mosseae, Rhizophagus irregularis, and Claroideoglomus etunicatum juvenile showed enhanced chlorophyll and photosynthetic levels, reducing salinity effects. Funneliformis mosseae had the most significant positive impact.

Analysis of widely targeted metabolites of quinoa sprouts (Chenopodium quinoa Willd.) under saline-alkali stress provides new insights into nutritional value.

Quinoa sprouts are a green vegetable rich in bioactive chemicals, which have multiple health benefits. However, there is limited information on the overall metabolic profiles of quinoa sprouts and the metabolite changes caused by saline-alkali stress. Here, a UHPLC-MS/MS-based widely targeted metabolomics technique was performed to comprehensively evaluate the metabolic profiles of quinoa sprouts and characterize its metabolic response to saline-alkali stress. A total of 930 metabolites were identified of which 232 showed significant response to saline-alkali stress. The contents of lipids and amino acids were significantly increased, while the contents of flavonoids and phenolic acids were significantly reduced under saline-alkali stress. Moreover, the antioxidant activities of quinoa sprouts were significantly affected by saline-alkali stress. The enrichment analysis of the differentially accumulated metabolites revealed that flavonoid, amino acid and carbohydrate biosynthesis/metabolism pathways responded to saline-alkali stress. This study provided an important theoretical basis for evaluating the nutritional value of quinoa sprouts and the changes in metabolites in response to saline-alkali stress.

Alkali injury-induced pathological lymphangiogenesis in the iris facilitates the infiltration of T cells and ocular inflammation.

Inflammatory lymphangiogenesis is intimately linked to immune regulation and tissue homeostasis. However, current evidence has suggested that classic lymphatic vessels are physiologically absent in intraocular structures. Here, we show that neolymphatic vessels were induced in the iris after corneal alkali injury (CAI) in a VEGFR3-dependent manner. Cre-loxP-based lineage tracing revealed that these lymphatic endothelial cells (LECs) originate from existing Prox1+ lymphatic vessels. Notably, the ablation of iridial lymphangiogenesis via conditional deletion of VEGFR3 alleviated the ocular inflammatory response and pathological T cell infiltration. Our findings demonstrate that iridial neolymphatics actively participate in pathological immune responses following injury and suggest intraocular lymphangiogenesis as a valuable therapeutic target for the treatment of ocular inflammation.

An alkali-extracted neutral heteropolysaccharide from Phellinus nigricans used as an immunopotentiator in immunosuppressed mice by activating macrophages.

A neutral heteropolysaccharide (PNANb) was isolated with alkali (0.1 M NaOH) from mycelia of Phellinus nigricans, and the structure, immunostimulating activity and some of the underlying molecular mechanisms of action of PNANb were explored in the current study. PNANb (14.95 kDa) predominantly consisted of Gal, Glc, and Man with minor Fuc. GC-MS and NMR analyses indicated that the backbone of PNANb was mainly composed of 6-α-Galp, 2,6-α-Galp with minor 3,6-ß-Glcp, which was substituted with complex side chains at C-2 of 2,6-α-Galp and C-3 of 3,6-ß-Glcp. Notably, PNANb (50 or 100 mg/kg) possessed immunoprotective effects in cyclophosphamide (Cy)-induced immunosuppressed C57BL/6 mice, which was supported by evidence including the enhancement of spleen and thymus indices, levels of serum immunoglobulins (IgG, IgM) and cytokines (IFN-γ, IL-2, IL-4, IL-10), and macrophage activity. However, the immunostimulation effects of PNANb were decreased when macrophages were depleted, underscoring the essential role of macrophages in the beneficial effects of PNANb in Cy-induced immunosuppressed mice. Further investigations in vitro indicated that PNANb activated macrophages through MAPK/NF-κB signaling pathways mediated by Toll-like receptor 4. Therefore, PNANb can serve as a prospective immunopotentiator in immunosuppression.

Short-term high-temperature pretreated compost increases its application value by altering key bacteria phenotypes.

Short-term high-temperature pretreatment can effectively shorten the maturity period of organic waste composting and improve the fertilizer efficiency and humification degree of products. To investigate the effect and mechanism of the end products on the saline-alkali soil improvement and plant growth, the short-term high-temperature pretreatment composting (SHC) and traditional composting (STC) were separately blended with saline-alkali soil in a ratio of 0-40 % to establish a soil-fertilizer blended matrix for cultivating Lolium perenne L. The pot experiments combined with principal component analysis showed Lolium perenne L. planted in 20 % SHC-blended saline-alkali soil had the best growth effect, and its biomass, chlorophyll content, and plant height were 109-113 % higher than STC. The soil physicochemical property analysis showed that SHC and STC increased the soil nutrient content, humification degree, and enzyme activity at any blending ratio. The microbial analysis showed that 20 % SHC in the saline-alkali soil stimulated the growth of functional microorganisms and the addition of SHC promoted the sulfur cycle, nitrogen fixation, and carbon metabolism in the soil-plant system. The correlation analysis showed that pH; nutrient contents; and urease, catalase, sucrase, and phosphatase activities in the saline-alkali soil were significantly correlated with plant growth indexes (p < 0.05). Georgenia and norank_f__Fodinicurvataceae had a stronger correlation with four types of enzyme activities (p < 0.01). SHC improved the saline-alkali soil and promoted plant growth by adjusting soil pH, increasing soil nutrients, and influencing soil enzyme activity and dominant flora. This study provides a theoretical basis for applying SHC products in soil improvement.

Solidification/stabilization and optimization of municipal solid waste incineration fly ash with aluminosilicate solid wastes.

Alkali-activation is an effective municipal solid waste incineration fly ash (MSWIFA) solidification/stabilization (S/S) technology. However, the characteristics of calcium-rich silica-poor aluminum phase in MSWIFA easily cause the structural instability and contamination of alkali activated MSWIFA S/S bodies. Therefore, the aluminosilicate solid wastes are used in this work to optimize the immobilization and structural properties. Results showed that incorporation of aluminosilicate solid wastes significantly improved the compressive strength and heavy metals pollution toxicity of MSWIFA S/S bodies. Compared to alkali activated MSWIFA, the compressive strength of S/S bodies with addition of coal fly ash, silica fume and granulated blast furnace slag improved by 31.0%, 47.6% and 50.8% when the curing time was 28 days, respectively. Leachability of Pb, Zn and Cd in these alkali activated MSWIFA S/S bodies was far below the threshold value specified in Standard GB16889. Aluminosilicate solid wastes provided abundant Si/Al structural units, and some new phases such as ettringite(AFt, 3CaO⋅Al2O3⋅3CaSO4⋅32H2O), calcium sulfoaluminate hydrate (3CaO⋅Al2O3⋅CaSO4⋅12H2O) and Friedel's salt (CaO⋅Al2O3⋅CaCl2⋅10H2O) can be detected in S/S matrix with aluminosilicate solid wastes, along comes increased the amount of the amorphous phases. Lower Ca/Si molar ratio tended to form the network structure gel similar to tobermorite with higher polymerization degree. Meanwhile, the silica tetrahedron of the gels changed from the oligomerization state like island to the hyperomerization state like chain, layer network or three-dimensional structure, and average molecular chain length increased. These findings provide theoretical basis for structural properties optimization and resource utilization of MSWIFA S/S matrices.

Vegetative cell wall protein OsGP1 regulates cell wall mediated soda saline-alkali stress in rice.

Plant growth and development are inhibited by the high levels of ions and pH due to soda saline-alkali soil, and the cell wall serves as a crucial barrier against external stresses in plant cells. Proteins in the cell wall play important roles in plant cell growth, morphogenesis, pathogen infection and environmental response. In the current study, the full-length coding sequence of the vegetative cell wall protein gene OsGP1 was characterized from Lj11 (Oryza sativa longjing11), it contained 660 bp nucleotides encoding 219 amino acids. Protein-protein interaction network analysis revealed possible interaction between CESA1, TUBB8, and OsJ_01535 proteins, which are related to plant growth and cell wall synthesis. OsGP1 was found to be localized in the cell membrane and cell wall. Furthermore, overexpression of OsGP1 leads to increase in plant height and fresh weight, showing enhanced resistance to saline-alkali stress. The ROS (reactive oxygen species) scavengers were regulated by OsGP1 protein, peroxidase and superoxide dismutase activities were significantly higher, while malondialdehyde was lower in the overexpression line under stress. These results suggest that OsGP1 improves saline-alkali stress tolerance of rice possibly through cell wall-mediated intracellular environmental homeostasis.

Genome-wide identification and characterization of FAD family genes in barley.

Fatty acid desaturases (FADs) play pivotal roles in determining plant stress tolerance. Barley is the most salt-tolerant cereal crop. In this study, we performed genome-wide identification and characterization analysis of the FAD gene family in barley (Hordeum vulgare). A total of 24 HvFADs were identified and divided into four subfamilies based on their amino acid sequence similarity. HvFADs unevenly distributed on six of seven barley chromosomes, and three clusters of HvFADs mainly occurred on the chromosome 2, 3 and 6. Segmental duplication events were found to be a main cause for the HvFAD gene family expansion. The same HvFAD subfamily showed the relatively consistent exon-intron composition and conserved motifs of HvFADs. Cis-element analysis in HvFAD promoters indicated that the expression of HvFADs may be subject to complex regulation, especially stress-responsive elements that may involve in saline-alkaline stress response. Combined transcriptomic data with quantitative experiments, at least five HvFADs highly expressed in roots under salt or alkali treatment, suggesting they may participate in saline or alkaline tolerance in barley. This study provides novel and valuable insights for underlying salt/alkali-tolerant mechanisms in barley.

Clinical pharmacist intervention in contraindications of the co-administration of cefoperazone and ambroxol hydrochloride injection.

BACKGROUND: Clinical pharmacists identified contraindications in two cases concerning the co-administration of cefoperazone and ambroxol hydrochloride injection, prompting a thorough investigation. CASE PRESENTATION: Clinically, two cases of contraindications for the co-administration of cefoperazone and ambroxol hydrochloride injection were discovered. After the intervention and analysis by clinical pharmacists, the possible reason could be the precipitation of free alkali due to the immediate administration of ambroxol after the infusion of cefoperazone. Clinical pharmacists suggested avoiding the co-administration of the two and recommended flushing the intravenous lines with 5% glucose injection or 0.9% sodium chloride injection during intravenous infusion to prevent direct drug interaction causing precipitation, thereby reducing the occurrence of adverse events. No adverse events occurred after the intervention, and no harm was caused to the patients. CONCLUSIONS: The co-administration of cefoperazone and ambroxol hydrochloride injection can lead to the precipitation of free alkali, posing a risk of adverse events. Clinical pharmacists' intervention could prevent this interaction. This practice has been shown to be effective, with no subsequent adverse events reported.

[Research and Application Progress of Biochar in Amelioration of Saline-Alkali Soil].

Saline-alkali land， as one of the farmland problems that seriously threatens grain yield in the 21st century， is widely distributed and has great potential for development. Biochar is a relatively efficient novel soil amendment， which can play an important role in alleviating the soil acid-base barrier， soil pollution control， carbon sequestration， and fertilizer slow release and has a great prospect in promoting sustainable agricultural development. In recent years， the research and application of biochar to improve saline-alkali soil have attracted much attention. However， due to the complexity and heterogeneity of the structural components of biochar， the improvement effect of biochar on saline-alkali soil is highly uncertain， and there is also a lack of systematic summary and in-depth discussion of the key mechanisms， which limits the further popularization and application of biochar technology in the improvement of saline-alkali soil. This study comprehensively analyzed the effects of biochar on physicochemical properties， nutrient availability， and biological characteristics of saline-alkali soil； summarized the improvement effects of biochar and modified biochar on saline-alkali soil and their effects on quality and efficiency； and elucidated the possible mechanism of biochar in the improvement of saline-alkali soil. The future research prospect of biochar was discussed in order to provide reference for further research and development of green， efficient， and accurate improvement technology of biochar in saline-alkali soil and its popularization and application.

Chemical (Alkali) Burn-Induced Neurotrophic Keratitis Model in New Zealand Rabbit Investigated Using Medical Clinical Readouts and In Vivo Confocal Microscopy (IVCM).

PURPOSE: Chemical eye injury is an acute emergency that can result in vision loss. Neurotrophic keratitis (NK) is the most common long-term manifestation of chemical injury. NK due to alkali burn affects ocular surface health and is one of its most common causes. Here, we established a rabbit model of corneal alkali burns to evaluate the severity of NK-associated changes. MATERIAL METHODS: Alkali burns were induced in NZ rabbits by treating the cornea with (i) a 5 mm circular filter paper soaked in 0.75 N NaOH for 10 s (Mild NK) and (ii) trephination using a guarded trephine (5 mm diameter and 150-micron depth), followed by alkali burn, with a 5 mm circular filter paper soaked in 0.75 N NaOH for 10 s (a severe form of NK). Immediately after, the cornea was rinsed with 10 mL of normal saline to remove traces of NaOH. Clinical features were evaluated on Day 0, Day 1, Day 7, Day 15, and Day 21 post-alkali burn using a slit lamp, Pentacam, and anterior segment optical coherence tomography (AS-OCT). NK-like changes in epithelium, sub-basal nerve plexus, and stroma were observed using in vivo confocal microscopy (IVCM), and corneal sensation were measured using an aesthesiometer post alkali injury. After 21 days, pro-inflammatory cytokines were evaluated for inflammation through ELISA. RESULTS: Trephination followed by alkali burn resulted in the loss of epithelial layers (manifested using fluorescein stain), extensive edema, and increased corneal thickness (550 µm compared to 380 µm thickness of control) evaluated through AS-OCT and increased opacity score in alkali-treated rabbit (80 compared to 16 controls). IVCM images showed complete loss of nerve fibers, which failed to regenerate over 30 days, and loss of corneal sensation-conditions associated with NK. Cytokines evaluation of IL6, VEGF, and MMP9 indicated an increased angiogenic and pro-inflammatory milieu compared to the milder form of NK and the control. DISCUSSION: Using clinical parameters, we demonstrated that the alkali-treated rabbit model depicts features of NK. Using IVCM in the NaOH burn animal model, we demonstrated a complete loss of nerve fibers with poor self-healing capability associated with sub-basal nerve degeneration and compromised corneal sensation. This pre-clinical rabbit model has implications for future pre-clinical research in neurotrophic keratitis.

Experimental study on municipal solid waste incineration bottom ash as a component of alkali-activated coal gangue-based geopolymer.

This study explores the potential of municipal solid waste incineration bottom ash (MSWI BA) and coal gangue as precursors for alkali-activated cementitious materials (CG-MBA). An examination of the impact of MSWI BA content, NaOH/Na2SiO3 ratio, liquid-solid ratio, and NaOH concentration on strength and reaction through the application of diverse analytical methodologies. Results demonstrate that CG-MBA offers significant environmental benefits compared to conventional cement. When used as a construction filling material, CG-MBA exhibits a remarkable 74.5 ~ 79.2 wt% reduction in carbon dioxide emissions and 70.6 ~ 77.0 wt% reduction in energy consumption. Additionally, CG-MBA effectively immobilizes heavy metal ions in MSWI BA, with a fixation efficiency exceeding 56.0%. These findings suggest that CG-MBA is a promising sustainable solution for waste management, offering significant environmental benefits while demonstrating effective heavy metal immobilization. This approach contributes to pollution control and promotes environmental sustainability in the construction industry.

Effects of alkali and alkaline earth metals on co-combustion of sewage sludge and coal slime: Combustion characteristics, interactions, and kinetics.

The co-combustion of sewage sludge (SS) and coal slime (CS) is a preferred method for their resource utilization, however, alkali and alkaline earth metals (AAEMs) in SS may affect the co-combustion process. In this work, the co-combustion behavior of AAEMs-rich SS and CS was investigated in terms of combustion characteristics, interactions, and combustion kinetics using a thermogravimetric analyzer. Further, the role of AAEMs in co-combustion was evaluated by loading Ca, K, Na, and Mg individually after pickling. The results revealed that co-combustion compensated for the limitations of the individual combustion processes, with SS reducing ignition and burnout temperatures and CS improving the comprehensive combustion characterization. Principal component analysis (PCA) showed that the effect of CS on co-combustion was more significant compared to SS. Significant synergies were observed in the weight loss phase of fixed carbon in the blends with 40%, 50%, and 60% CS ratios, where the peak temperature of fixed carbon combustion was reduced by 9.8 °C, 12.6 °C, and 13.1 °C, respectively, compared to the theoretical values. The effects of AAEMs on combustion were as follows: all AAEMs promoted the precipitation of volatiles except Ca, which showed inhibition of light volatiles; AAEMs had a significant catalytic effect on fixed carbon combustion. The improvement effect of AAEMs on the comprehensive combustion characteristics during co-combustion was Na > K > Mg > Ca. The catalytic effect of Na on fixed carbon was strongest at a loading of 5%, leading to a decrease in the apparent activation energy of fixed carbon combustion by 22.2 kJ/mol and a change in reactor order from n = 1 to n = 1.2 during co-combustion. This work provides a better understanding of the role of AAEMs in SS-CS co-combustion.

Ultrasonic-enhanced photocatalysis through piezoelectric and cavitation effects for lignin depolymerization.

Although a promising method for lignin depolymerization, photocatalysis faces the challenge of low efficiency. In this study, MoS2/ZnO heterojunction catalysts, endowed with piezocatalysis and photocatalytic capabilities, were crafted through Zn ion intercalation for the depolymerization of phenoxyphenylethanol (PP-ol) and alkali lignin. Then, the synergistic interplay between ultrasonic-induced piezoelectric fields and heterojunctions was analyzed. The amalgamation of the piezoelectric field and heterojunction in MoS2/ZnO catalysts resulted in a diminished photogenerated hole/electron recombination efficiency, thereby fostering the generation of ·OH during the reaction. This pivotal role of ·OH emerged as a crucial reactive substance, converting 95.8 % of PP-ol through ß-O-4 bond breaking within a 3-h treatment. By incorporating ultrasonic, the contact probability of PP-ol with the catalyst was significantly improved, resulting in efficient conversion even with a reduced amount of acetonitrile in the solvent system (20 %). Furthermore, ultrasonic-light methods show high efficiency for depolymerizing Alkali lignin (AL), with 33.2 % of lignin undergoing depolymerization in a 4-h treatment. This treatment simultaneously reduces the molecular weight of AL and cleaves numerous chemical bonds within it. Overall, this work presents a green approach to lignin depolymerization, providing insights into the synergistic action of ultrasonic and photocatalysis.

Effect of Deashing Treatment on Ash Fusion Characteristics of Biochar from Bamboo Shoot Shells.

To investigate the influence of deashing on fusion characteristics, a combined method of water and acid washing with different sequences (water washing followed by acid washing, and acid washing followed by water washing) was used to treat the biochar of bamboo shoot shells (BBSSs). The results show that deashing decreased the K content of the biochar from 50.3% to 1.08% but increased the Si content from 33.48% to 89.15%. The formation of silicates and aluminosilicates from alkali metal oxides with silicon was an inevitable result of ash phase transformation at the high temperatures used to improve the fusion temperature (>1450 °C). The thermochemical behavior of ash mainly occurs at 1000 °C. The deashing treatment significantly reduced the reaction intensity during the high-temperature process. This significantly increased the thermal stability of the ash. The adjustment of the washing sequence had a slight impact on the chemical compositions, but the differences in ash micromorphology were obvious. Deashing treatments with different washing sequences can significantly improve ash fusion properties effectively and reduce the risk of scaling, slagging, and corrosion. This study provides a new and reasonable strategy for the deashing of biochar to commercially utilize bamboo shoot shell resources.

Structural and rheological properties of diluted alkali soluble pectin from apple and carrot.

Pectin, a complex polysaccharide found in plant cell walls, plays a crucial role in various industries due to its functional properties. The diluted alkali-soluble pectin (DASP) fractions that result from the stepwise extraction of apples and carrots were studied to evaluate their structural and rheological properties. Homogalacturonan and rhamnogalacturonan I, in different proportions, were the main pectin domains that composed DASP from both materials. Atomic force microscopy revealed that the molecules of apple DASP were longer and more branched. A persistence length greater than 40 nm indicated that the pectin molecules deposited on mica behaved as stiff molecules. The weight-averaged molar mass was similar for both samples. Intrinsic viscosity values of 194.91 mL·g-1 and 186.79 mL·g-1 were obtained for apple and carrot DASP, respectively. Rheological measurements showed greater structural strength for apple-extracted pectin, whereas carrot pectin was characterized by a higher linear viscoelasticity limit. This comparison showed that the pectin fractions extracted by diluted alkali are structurally different and have different rheological properties depending on their botanical origin. The acquired insights can enhance the customized use of pectin residue and support further investigations in industries relying on pectin applications.

Combined dilute alkali and milling process enhances the functionality and gut microbiota fermentability of insoluble corn fiber.

In this study, we developed a process combining dilute alkali (NaOH or NaHCO3) and physical (disk milling and/or ball milling) treatments to improve the functionality and fermentability of corn fiber. The results showed that combining chemical with physical processes greatly improved the functionality and fermentability of corn fiber. Corn fiber treated with NaOH followed by disk milling (NaOH-DM-CF) had the highest water retention (19.5 g/g), water swelling (38.8 mL/g), and oil holding (15.5 g/g) capacities. Moreover, NaOH-DM-CF produced the largest amount (42.9 mM) of short-chain fatty acid (SCFA) during the 24-hr in vitro fermentation using porcine fecal inoculum. In addition, in vitro fermentation of NaOH-DM-CF led to a targeted microbial shifting to Prevotella (genus level), aligning with a higher fraction of propionic acid. The outstanding functionality and fermentability of NaOH-DM-CF were attributed to its thin and loose structure, decreased ester linkages and acetyl groups, and enriched structural carbohydrate exposure.

Remediation of soda-saline-alkali soil through soil amendments: Microbially mediated carbon and nitrogen cycles and remediation mechanisms.

Due to the high salt content and pH value, the structure of saline-sodic soil was deteriorated, resulting in decreased soil fertility and inhibited soil element cycling. This, in turn, caused significant negative impacts on crop growth, posing a major challenge to global agriculture and food security. Despite numerous studies aimed at reducing the loss of plant productivity in saline-sodic soils, the knowledge regarding shifts in soil microbial communities and carbon/nitrogen cycling during saline-sodic soil improvement remains incomplete. Consequently, we developed a composite soil amendment to explore its potential to alleviate salt stress and enhance soil quality. Our findings demonstrated that the application of this composite soil amendment effectively enhanced microbial salinity resistance, promotes soil carbon fixation and nitrogen cycling, thereby reducing HCO3- concentration and greenhouse gas emissions while improving physicochemical properties and enzyme activity in the soil. Additionally, the presence of CaSO4 contributed to a decrease in water-soluble Na+ content, resulting in reduced soil ESP and pH by 14.64 % and 7.42, respectively. Our research presents an innovative approach to rehabilitate saline-sodic soil and promote ecological restoration through the perspective of elements cycles.

Soil amendments reduce CH4 and CO2 but increase N2O and NH3 emissions in saline-alkali paddy fields.

Limited research has been conducted on ammonia (NH3) volatilization and greenhouse gases (GHGs) emissions in saline-alkali paddy fields, along with complex interaction involving various genes (16sRNA, amoA, narG, nirK, nosZ, and nifH). This study employed mesocosm-scale experiment to investigate NH3 volatilization and GHGs emissions, focusing on bacterial communities and genic abundance, in saline-alkali paddy fields with desulfurized gypsum (DG) and organic fertilizer (OF) amendments. Compared to the control (CK) treatment, DG and OF treatments reduced methane (CH4) and carbon dioxide (CO2) emissions by 78.05 % and 26.18 %, and 65.84 % and 11.62 %, respectively. However, these treatments increased NH3 volatilization by 26.26 % and 45.23 %, and nitrous oxide (N2O) emission by 41.00 % and 12.31 %. Notably, NH3 volatilization primarily stemmed from ammonia nitrogen (NH4+-N), rather than total nitrogen (TN) in soil and water. N2O was mainly produced from nitrate nitrogen (NO3--N) in soil and water, as well as NH4+-N in water. The increase in NH3 volatilization and N2O emission in DG and OF treatments, was attributed to the reduced competition among bacterial communities, rather than the increased bacterial activity and genic copies. These findings offer valuable insights for managing nutrient loss and gaseous emissions in saline-alkali paddy fields.