Search Results (1,411)

Morchella sextelata a species of high nutritional and economic value, is widely cultivated. To investigate how different cultivation environments affect the soil physicochemical properties and microbial communities associated with common morel, this study established cultivation plots under three distinct settings: apple orchard canopies, dry upland fields, and paddy fields. The objective was to compare the differential impacts of common morel cultivation on soil environmental conditions across these habitats. The results indicate that cultivating common morel effectively enhances soil fertility. Across all environments, soil hydrolyzable nitrogen (HN), available potassium (AK), and organic matter content were higher than in the control. In apple orchard and dryland soils, total phosphorus (TP), total potassium (TK), available phosphorus (AP), and pH values were also elevated compared to the control, with most differences reaching significant levels. Solid Sucrase (S-SC) activity increased in all environments compared to the control, with values of 17.52 mg/d/g in PG, 17.39 mg/d/g in HD, and 21.68 mg/d/g in DT soils. Soil Amylase (S-AL) activity was higher in PG (451.28 μg/h/g) and HD (475.38 μg/h/g) soils. In contrast, Soil-acid phosphatase (S-ACP) activity was significantly elevated in DT soil (2922.08 nmol/h/g). PG soil exhibited significantly higher activities of Solid-Catalase (S-CAT), Solid polyphenol oxidase (S-PPO), and Solid Urease (S-UE), with S-CAT reaching 952.5 μmol/h/g. Following common morel cultivation, bacterial richness and diversity decreased across all conditions, while fungal richness increased but diversity declined. At the phylum level, Proteobacteria remained the dominant bacterial group, accounting for 26.78% in PG, 28.27% in HD, and 20.05% in DT soils. Ascomycota was the predominant fungal phylum, comprising 68.03% in PG, 72.16% in HD, and 68.94% in DT soils. Predicted bacterial functional pathways were primarily associated with metabolism, genetic information processing, environmental information processing, and cellular processes. Key metabolic pathways included carbohydrate metabolism, amino acid metabolism, and metabolism of cofactors and vitamins. fungal functional guilds were mainly classified as pathotrophic, pathotrophic–saprotrophic, pathotrophic–saprotrophic–symbiotrophic, and saprotrophic. Among these, saprotrophic and pathotrophic guilds showed higher abundance compared to the control. This shift is characterized by a reduction in both the diversity and abundance of beneficial microorganisms, alongside an increase in the richness of harmful microbial taxa. The combined effect of these factors disrupts the soil microbial equilibrium. The findings of this study provide a theoretical foundation for the cultivation of common morel and the management of associated soils. Full article

Hydrothermal carbonization (HTC) has emerged as a promising technique for food waste treatment. However, food waste is composed of complex components, including refractory proteins and polysaccharides, which lead to low efficiency and high costs during the HTC process. Enhancing the decomposition of food waste while enabling efficient nutrient recovery remains a significant challenge for the widespread application of HTC in food waste management. This study introduces deep eutectic solvents (DESs) to enhance treatment efficiency during the HTC of food waste. A comprehensive characterization of the resulting hydrochar and aqueous phase was conducted, and the effect of DES addition on the migration and speciation of phosphorus and nitrogen species during HTC was investigated. The results indicated that the addition of DESs promoted the decomposition of food waste, reducing the hydrochar yield from 22.6% to 20.2% and decreasing the volatile matter content in the hydrochar from 86.63% to 71.60% at 200 °C. Additionally, DESs significantly lowered the nitrogen content in the hydrochar from 5.99% to 3.77%. By disrupting the hydrogen-bonding networks in proteins and polysaccharides, DESs facilitated the dissolution of organic matter into the aqueous phase. Furthermore, with DES addition, 5.06 mg of phosphorus species was enriched in the hydrochar, compared to only 1.78 mg in the control group without DESs. This study provides a sustainable strategy for the efficient treatment of food waste while simultaneously enabling the effective recovery of valuable nutrients. Full article

This study aimed to reveal the rhizosphere microbial community structure, carbon–nitrogen–phosphorus (C-N-P) nutrient cycling processes, and functional gene characteristics of Pinus massoniana and Schima superba in mixed forests. Furthermore, we sought to elucidate the microbial mechanisms by which mixed-species afforestation enhances soil quality improvement, providing a theoretical basis in soil microbiology for the cultivation of these mixed forests. The research subjects included pure P. massoniana plantations (CLPs), pure S. superba plantations (CLSs), and individual P. massoniana (HJP) and S. superba (HJS) trees within mixed plantations (HJLs). We collected rhizosphere and bulk soil samples to analyze their physicochemical properties and enzyme activities. Metagenomic sequencing was employed to profile the rhizosphere microbial communities and functional genes involved in C-N-P cycling. Furthermore, by integrating a functional gene co-occurrence network analysis with structural equation modeling (SEM), we systematically elucidated the coupling relationships among the stand types, soil properties, microbial communities, and nutrient cycling. Mixed planting significantly improved soil quality; compared to the CLP and CLS forests, the nitrate nitrogen (NO₃⁻-N) content in the mixed forest soils increased by 121.01% and 120.10% (p < 0.05), and the activity of urease (URE) also significantly increased by 123.99% and 49.56%, respectively. Mixing significantly altered the microbial community structure. In the bacterial community of the mixed forests, the abundance of nitrogen-fixing and potentially phosphorus-solubilizing bacteria from the genera Paraburkholderia and Burkholderia increased. In the fungal community, the arbuscular mycorrhizal fungus Rhizophagus, which possesses a nutrient absorption advantage, exhibited absolute dominance, with its relative abundance ranging from 14.84% to 88.81%. The abundances of genes associated with denitrification and phosphorus starvation regulation were significantly upregulated in the mixed forests; notably, the abundance of phosphorus starvation regulation genes in the HJSs was 18.84% higher than that in the CLSs. A co-occurrence network analysis demonstrated that the proportion of positive correlation edges in the HJP nitrogen cycling network reached as high as 75.0%, and the average degree of the HJS phosphorus cycling network (2.691) surpassed that of the CLSs. The structural equation modeling further revealed that the association strength between the fungi and phosphorus cycling genes in the mixed forests increased to R² = 0.915 (p < 0.01) from R² = 0.213 in the pure forests. This mixed planting practice transforms nutrient cycling from a resource-competitive mode to a microbially synergized mode, thereby forming an efficient endogenous nutrient cycling system. This synergistic rhizosphere microbial effect is a key internal mechanism for overcoming nutrient bottlenecks and should serve as a diagnostic indicator of soil recovery in the ecological restoration of degraded pine forests. Full article

Sewage sludge (SS) is a by-product of wastewater treatment processes (WWTPs) and is rich in organic matter and essential nutrients like nitrogen, phosphorus, and potassium, making it a potential fertilizer for agricultural use. However, its application is often limited due to the presence of pathogenic bacteria, viruses, metals, and organic contaminants that can accumulate in soils and crops, raising concerns about food safety. Sewage sludge is additionally challenging to handle due to its high moisture content, low density, and odor emission. To mitigate environmental risks and enhance its usability as a soil fertilizer, SS must be stabilized. Various techniques, including chemical, physical, and biological, can be used to stabilize SS. The addition of lime and composting has received particular attention among these techniques owing to the benefits they offer. Both methods effectively control and eliminate pathogens and reduce metal bioavailability, thus improving their agricultural utility. This review emphasizes the importance of using SS for agricultural purposes, placing particular focus on the procedures of composting and liming to stabilize and enhance the quality of SS, hence promoting its safety. Full article

Sustainable fertilization strategies are required to reduce dependence on synthetic inputs, enhance waste recycling, and improve agricultural resilience under climate change. This study evaluates the effects of wastewater-derived sludge, particularly when modified with Fe-montmorillonite, on phosphorus availability and early development of Zea mays. Methods: Germination and early growth of Zea mays were assessed under four treatments: (i) untreated soil (Control); (ii) soil amended with sludge from the Cardeal Wastewater Treatment Plant (SC); (iii) soil amended with Fe-montmorillonite-modified sludge (TechPhos, ST); and (iv) soil amended with a commercial phosphorus salt (PS). Soil characterization was conducted using XRF, XRD, and FTIR. Plant responses were evaluated through laboratory (5 days) and pot (22 days) experiments. Results: ST showed the highest performance, with a germination index of 171.7 and improved biomass, leaf development, and chlorophyll content compared to Control and SC. ST also performed similarly to or better than the commercial fertilizer (PS), indicating high phosphorus efficiency. Conclusions: The integration of nanostructured modified montmorillonite with wastewater-derived sludge represents a promising alternative phosphorus source for early maize development. Its application supports waste valorization and circular economy approaches while contributing to improved soil fertility and more sustainable nutrient management under climate change scenarios. Full article

Acidified soils in greenhouse vegetable systems constrain crop production and soil ecological functions. This study investigated the effects of different amendment treatments on soil ecological factors in acidified soils under greenhouse spinach cultivation in Baoqing County, China. Three treatments were established: farmyard manure alone (T1), Haijuneng soil amendment, an alkaline oyster-shell-based soil conditioner, alone (T2), and the combined application of farmyard manure and Haijuneng soil amendment (T3). High-throughput sequencing of the 16S rRNA gene combined with functional prediction was used to analyze soil bacterial community characteristics and their relationships with soil physicochemical properties and enzyme activities. The results showed that soil pH increased significantly under T2 compared with T1 (4.59 vs. 4.14), along with higher exchangeable calcium (16.11 vs. 12.20 cmol kg⁻¹) and exchangeable magnesium (5.54 vs. 3.83 cmol kg⁻¹). In contrast, T3 showed the highest organic matter content (48.54 g kg⁻¹) and phosphatase activity. Compared with T1, both T2 and T3 increased urease activity and altered bacterial community structure and functional composition, while microbial diversity was highest under T2. Soil pH and available phosphorus were the main factors driving bacterial community variation, whereas pH, exchangeable calcium, and exchangeable magnesium were significantly correlated with multiple dominant genera and KEGG level 2 pathways. Overall, the amendment strategies showed distinct effects: compared with the conventional practice of farmyard manure alone, Haijuneng soil amendment alone was more effective in partially alleviating soil acidification, whereas its combined application with farmyard manure was more favorable for soil organic matter accumulation and enhancing soil phosphorus supply potential. Full article

Although bud banks are key components of vegetation regeneration in degraded alpine meadows, their relationships with soil conditions on the Qinghai–Tibet Plateau remain insufficiently understood. In this study, we investigated bud bank composition and density, plant functional group biomass, soil physicochemical properties, and soil microbial biomass across five degradation stages of alpine meadows in a long-term controlled grazing experiment. Field sampling was conducted in mid-August 2021, and the relationships between bud bank densities, plant biomass, and soil variables were evaluated using comparative statistical analyses, redundancy analysis, and structural equation modeling. Bud bank density increased from non-degraded to moderately degraded meadows, reaching 3075 buds m⁻², but declined sharply in severely degraded meadows to 183 buds m⁻². Regarding distinct bud types, rhizome and tiller bud densities peaked in moderately degraded alpine meadows (1217 and 1750 buds m⁻², respectively), whereas dicot bud density peaked in lightly degraded meadows. Bud bank density was positively associated with higher soil moisture content and negatively associated with increased soil bulk density. Moreover, bud bank density was positively correlated with soil organic carbon, total phosphorus, ammonium nitrogen, and soil microbial biomass carbon, nitrogen, and phosphorus. Our findings indicate that soil conditions may favor the maintenance of high bud bank density in moderately degraded meadows with high soil moisture, low bulk density, and more nutrient-rich soil conditions in moderately degraded meadows. Overall, our results indicate that alpine meadow degradation influences belowground regenerative capacity through changes in soil conditions and associated shifts in bud bank dynamics. Therefore, assessments and restoration of degraded alpine meadows should consider bud bank persistence in addition to aboveground vegetation characteristics. Full article

The transition towards circular agriculture requires sustainable fertilization strategies that maintain crop productivity, reducing environmental impacts associated with synthetic inputs. In this study, compost-derived biofertilizers produced from cattle manure, with and without structuring agents (wheat straw and almond pruning), were evaluated as alternatives to mineral fertilization for lettuce (Lactuca sativa L.) grown under controlled greenhouse conditions. A two-cycle pot experiment was conducted to increase total nitrogen, extractable phosphorus and exchangeable potassium, while slightly decreasing soil pH. Mineral fertilization produced the highest biomass in the first growing cycle, whereas compost treatments achieved comparable yields and showed clear residual effects in the second cycle. Multispectral sensing shows to be a useful non-destructive tool for monitoring crop development. Red-edge-based indices (NDRE) showed high sensitivity to variations in nutrient content dynamics. Generalized additive models (GAMs) enabled nutrient prediction, with strong performance for phosphorus (R² = 0.79) and selected micronutrients and moderate performance for nitrogen (R² = 0.62) and weaker performance for potassium (R² = 0.45). These results indicate that combining compost-based fertilization with multispectral sensing can improve nutrient use efficiency and support precision horticulture under circular agricultural frameworks. Full article

Here, the proximate composition, total amino acid content and antioxidant activity of Agria, Désirée and Kennebec potato varieties cultivated on the Matese plateau (Campania region, Southern Italy) were evaluated. Significant differences were observed among varieties in terms of proteins (1.98–3.07 g/100 g FW), carbohydrates (12.05–15.78 g/100 g FW) and moisture (78.42–84.68 g/100 g FW), while lipids were consistently low (~0.1 g/100 g FW), ~2.6-fold lower than ‘gold’ potatoes, used as a reference. Ashes were relatively high (1.10–1.39 g/100 g FW), ~1.4-fold higher than ‘gold’ potatoes. Total amino acid profiles were similar, although statistically significant differences were observed for Glx (glutamic acid + glutamine) and Asx (aspartic acid + asparagine), which are the most abundant amino acids, followed by valine, arginine and lysine. The chemical score of essential amino acids highlights that Matese potato varieties have a high nutritional content of phenylalanine + tyrosine and threonine, with average chemical scores of ~99.8% and 91.6%, respectively, while leucine is the limiting amino acid. The free amino acid profile does not show statistically significant differences. The total phenolic content (TPC) of analysed varieties (57.85–123.27 mg GAE/100 g of FW) was higher than those reported in the literature and directly correlated with the evaluated antioxidant activity (ABTS and DPPH). Finally, Matese potatoes are rich in potassium, phosphorus, calcium and magnesium, with minor minerals (~1.6%) and selenium traces (~0.53 µg/100 g FW). Overall, these findings highlight the potential of Matese potatoes to enhance local consumption, preserve culinary heritage and support gastronomic tourism growth. Full article

Mineral elements are components of metabolites in tea plants and directly contribute to taste formation in brewed tea infusions. Like quality-related compounds such as tea polyphenols and free amino acids, their accumulation and leachability are strongly influenced by growing conditions. To investigate the relationships between mineral elements and flavor quality, 56 Tieguanyin tea samples collected across different elevation gradients were analyzed. Unlike previous altitude-related studies that mainly focused on conventional metabolites, this study simultaneously examined mineral element contents in both dry tea leaves and brewed infusions, together with sensory evaluation and the quantification of tea polyphenols, free amino acids, caffeine, and catechin metabolites. Compared with low-elevation teas (300–400 m), high-elevation teas (600–800 m and above 800 m) exhibited superior flavor quality, with higher free amino acids and tea polyphenols, and lower phenol-to-amino acid ratios and caffeine contents, whereas catechin metabolites showed only a weak association with elevation. In dry tea leaves, analysis of total mineral elements indicated that higher magnesium (Mg) and phosphorus, together with lower aluminum, copper, manganese, and cobalt, were positively associated with both elevation and tea quality. In brewed tea infusions, Mg was positively correlated with quality, whereas sodium (Na) and potassium (K) were negatively associated. Notably, Na was 47% higher and K was 8% higher in teas from above 800 m than in those from 600–800 m, enabling further separation of the two high-elevation groups. These findings provide a scientific basis for improving Oolong tea quality through optimized cultivation practices and nutrient regulation. Full article

Rice seedlings are typically grown in high-phosphorus nursery soils in practice, which reduces rice root growth and the plant’s ability to adapt to adverse conditions after transplantation to the paddy field. Thus, it is important to improve rice root development in high-phosphorus nursery soils. Rice root developments are closely connected with soil microorganisms. Arbuscular mycorrhizal fungi (AMF) can promote rice root growth and help improve rice performance in resisting adverse conditions. To illustrate the mechanisms of rice seedlings with AMF inoculation under suitable and high-phosphorus nursery soils in resisting adverse conditions, rice seedlings were cultivated in suitable and high-phosphorus nursery soils inoculated with AMF JD5 (Paraglomus sp.) and transplanted into soda saline–alkaline soils following successful AMF inoculation. Results showed that under high-phosphorus conditions, AMF JD5 inoculation significantly promoted plant height and root elongation, likely through increased total chlorophyll content. Concurrently, proline content was reduced, whereas soluble sugar and soluble protein contents were elevated, indicating alleviation of osmotic stress induced by saline–alkaline conditions. Moreover, AMF JD5-inoculated seedlings exhibited increased CAT activity, which efficiently scavenged reactive oxygen species (ROS) generated under salt–alkaline stress and reduced lipid peroxidation. However, thiobarbituric acid reactive substances (TBARS) content was significantly decreased with AMF inoculation in high-phosphorus conditions. Collectively, these findings suggest that AMF JD5 inoculation in high-phosphorus nursery soils establishes a physiological and biochemical foundation that maintains rice resilience against saline–alkaline stress throughout early growth. Full article

Conventional tillage, a soil preparation practice used to produce a fine seedbed, can disturb the soil profile by promoting soil compaction and soil organic matter (SOM) degradation. In contrast, conservation tillage, such as no-till, has the potential to sustain or increase SOM. This study aimed to (1) quantify soil organic carbon (SOC) content under conservation tillage and conventional tillage practices, (2) describe the degree of aromaticity of bioavailable SOC using fluorescence spectroscopy, and (3) correlate SOC quantity with nitrogen and phosphorus retention in soils. Fluorescence spectroscopy is a sensitive and non-destructive tool that allows for the assessment of bioavailable SOC quality related to the molecular structure, degree of aromaticity (cyclic molecules with carbon double bonds), and recalcitrance (difficulty of decomposition) of organic compounds. This study employed fluorescence excitation–emission matrices combined with parallel factor analysis (EEM-PARAFAC) to identify humic-like, fulvic-like, and protein-like substances. Data on agricultural management practices were collected from spring 2014 until fall 2017. We obtained soil samples (fall 2017) from farms in the Western Lake Erie Basin, Ohio, and performed geochemical characterization in the bulk soil and aqueous extraction. Our results showed that no-till and minimal tillage fields consistently had greater SOC and fluorescence intensity in the humic-like acids region when compared to conventional tilled fields (no-till: 34,000 mg TOC kg⁻¹; tilled six times: 16,000 mg TOC kg⁻¹). No-till enhanced SOC stabilization. In addition, conservation tillage practices retained the largest total nitrogen (no-till: 2800 mg TN kg⁻¹; tilled six times: 1350 mg TN kg⁻¹) and total phosphorus (no-till: 470 mg TP kg⁻¹; tilled six times: 250 mg TP kg⁻¹) concentrations at all studied depths (0–30 cm) when compared to conventional tilled fields. Conservation tillage promotes the accumulation of highly aromatic organic compounds favoring high cation exchange capacity, and NO₃⁻ and PO₄³⁻ retention and plant bioavailability. Full article

Meadow albic soils in the Sanjiang Plain of Northeast China are characterized by a compact plow layer, weak structural stability, low organic matter content, and limited nutrient availability, which restrict crop productivity in maize–soybean rotation systems. A two-year field experiment (2023–2024) was conducted to compare the effects of mineral fertilizer alone (CF) and CF combined with carbon-based organic fertilizer (CF+COF), humic acid organic fertilizer (CF+HA), or biochar-based fertilizer (CF+BC) on soil properties and crop yield. Soil aggregate composition, pH, organic carbon, total nitrogen, alkali-hydrolyzable nitrogen, available phosphorus, available potassium, and enzyme activities were measured together with yield and 100-grain weight. Compared with CF alone, the combined application of organic amendments generally improved soil properties and increased crop yield, although the magnitude and pattern of response differed among materials. CF+COF was more effective in increasing the proportion of medium-sized aggregates, enhancing alkali-hydrolyzable nitrogen and some enzyme activities, and achieving relatively high yields in both maize and soybean seasons. CF+HA showed comparatively balanced effects on aggregate composition and nutrient availability, whereas CF+BC was more effective in maintaining relatively high soil pH, increasing available phosphorus, and promoting larger aggregates at later growth stages. Overall, all three organic amendments combined with mineral fertilizer were beneficial for improving meadow albic soil and increasing crop yield, with CF+COF showing the best overall performance under the conditions of this study. Full article

Excessive dietary sodium intake has been associated with immune dysregulation, yet its impact on bone health and immune cell dynamics within the bone–immune axis remains poorly understood. We developed a longitudinal murine model to investigate the effects of a high-salt diet (HSD) on bone properties and immunity. Male and female C57BL/6J and Foxp3-GFP mice underwent unilateral nephrectomy and were fed either a normal salt diet (0.2% NaCl) or HSD (4% NaCl) for 20, 60, or 150 days. HSD mice exhibited a transient increase in systolic blood pressure and sustained calciuria without changes in serum calcium or PTH. Progressive impairment of femoral strength and tibial trabecular microarchitecture were observed, along with reduced cortical calcium and phosphorus content. Immune analysis revealed early splenic and bone marrow activation of effector T cells, with increased Th17 and Tc17 populations and a disrupted Th17/Treg balance at 20 days. These changes normalized by 60 days and shifted to suppressed T cell activation at 150 days, suggesting a biphasic immune response. Th17/Treg ratio was associated with bone deterioration. Notably, both sexes showed comparable physiological and immune trends. This integrative model provides a platform to dissect mechanisms linking chronic salt overload, immune dysregulation, and bone fragility. Full article

Mycosporine-like amino acids (MAAs), a class of secondary metabolites characterized by a cyclohexenone or cyclohexenimine ring structure bound to amino acid residues, are widely distributed in algae. These compounds exhibit strong ultraviolet-absorbing and antioxidant activities, making them attractive candidates for natural sunscreen formulations. However, the low productivity of MAAs in microalgae severely hampers commercial viability. Asterarcys sp., a fast-growing, heat- and light-tolerant microalga, has recently been demonstrated to produce high levels of MAAs under UV irradiation. In this study, phosphorus limitation was found to stimulate rapid MAAs accumulation in Asterarcys sp. SCSIO-46548. After eight days of cultivation, microalgal cells grown in phosphorus-free medium (0 mg L⁻¹) showed a sixfold higher MAAs content (1.08% DW) compared to the group supplied with 5.60 mg L⁻¹ phosphorus (0.18% DW). However, the accumulation of MAAs began to plateau under phosphorus deprivation. Based on integrated homology alignment with cyanobacteria and functional domain validation, a putative biosynthetic pathway for mycosporine-serine in Asterarcys sp. SCSIO-46548 was proposed. Importantly, the gene expression of desmethyl-4-deoxygadusol synthase (DDGS) exhibited a 2.75-fold upregulation under phosphorus limitation. Complementary bioinformatic analyses further characterized the subcellular localization and major physicochemical properties of the candidate enzymes involved. In conclusion, phosphorus limitation is an effective strategy to enhance MAAs production in Asterarcys sp. SCSIO-46548 by upregulating the expression of key biosynthetic genes, such as DDGS. This finding provides an effective solution to the low MAAs productivity in microalgae cultivation. Full article