How sediment dredging alters phosphorus dynamics in a lowland rural river?

China's lowland rural rivers are facing severe eutrophication problems due to excessive phosphorus (P) from anthropogenic activities. However, quantifying P dynamics in a lowland rural river is challenging due to its complex interaction with surrounding areas. A P dynamic model (River-P) was specifically designed for lowland rural rivers to address this challenge. This model was coupled with the Environmental Fluid Dynamics Code (EFDC) and the Phosphorus Dynamic Model for lowland Polder systems (PDP) to characterize P dynamics under the impact of dredging in a lowland rural river. Based on a two-year (2020-2021) dataset from a representative lowland rural river in the Lake Taihu Basin, China, the coupled model was calibrated and achieved a model performance (R2>0.59, RMSE<0.04 mg/L) for total P (TP) concentrations. Our research in the study river revealed that (1) the time scale for the effectiveness of sediment dredging for P control was ∼300 days, with an increase in P retention capacity by 74.8 kg/year and a decrease in TP concentrations of 23% after dredging. (2) Dredging significantly reduced P release from sediment by 98%, while increased P resuspension and settling capacities by 16% and 46%, respectively. (3) The sediment-water interface (SWI) plays a critical role in P transfer within the river, as resuspension accounts for 16% of TP imports, and settling accounts for 47% of TP exports. Given the large P retention capacity of lowland rural rivers, drainage ditches and ponds with macrophytes are promising approaches to enhance P retention capacity. Our study provides valuable insights for local environmental departments, allowing a comprehensive understanding of P dynamics in lowland rural rivers. This enable the evaluation of the efficacy of sediment dredging in P control and the implementation of corresponding P control measures.

Disentangling microbial coupled fillers mechanisms for the permeable layer optimization process in multi-soil-layering systems.

The multi-soil-layering (MSL) systems is an emerging solution for environmentally-friendly and cost-effective treatment of decentralized rural domestic wastewater. However, the role of the seemingly simple permeable layer has been overlooked, potentially holding the breakthroughs or directions to addressing suboptimal nitrogen removal performance in MSL systems. In this paper, the mechanism among diverse substrates (zeolite, green zeolite and biological ceramsite) coupled microorganisms in different systems (activated bacterial powder and activated sludge) for rural domestic wastewater purification was investigated. The removal efficiencies performed by zeolite coupled with microorganisms within 3 days were 93.8% for COD, 97.1% for TP, and 98.8% for NH4+-N. Notably, activated sludge showed better nitrification and comprehensive performance than specialized nitrifying bacteria powder. Zeolite attained an impressive 89.4% NH4+-N desorption efficiency, with a substantive fraction of NH4+-N manifesting as exchanged ammonium. High-throughput 16S rRNA gene sequencing revealed that aerobic and parthenogenetic anaerobic bacteria dominated the reactor, with anaerobic bacteria conspicuously absent. And the heterotrophic nitrification-aerobic denitrification (HN-AD) process was significant, with the presence of denitrifying phosphorus-accumulating organisms (DPAOs) for simultaneous nitrogen and phosphorus removal. This study not only raises awareness about the importance of the permeable layer and enhances comprehension of the HN-AD mechanism in MSL systems, but also provides valuable insights for optimizing MSL system construction, operation, and rural domestic wastewater treatment.

Acute inhibitory effects of tire wear particles on the removal of biological phosphorus：The critical role of aging in improving environmentally persistent free radicals.

A comparative study explored how photoaging, ozonation aging, and Fenton aging affect tire wear particles (TWPs) and their phosphorus (P) removal in activated sludge. Aging altered TWPs' properties, increasing surface roughness, porosity, and generating more small particles, especially environmental persistent free radicals (EPFRs) in ozonation and Fenton aging. Post-aging TWPs (50 mg/L) inhibited sludge P removal significantly (p < 0.05), with rates of 44.3% and 59.6% for ozonation and Fenton aging, respectively. In addition, the metabolites involved in P cycling (poly-ß-hydroxyalkanoates: PHA and glycogen) and essential enzymes (Exopolyphosphatase: PPX and Polyphosphate kinase: PPK) were significantly inhibited (p < 0.05). Moreover, TWPs led to a decrease in microbial cells within the sludge and altered the community structure, a situation exacerbated by the aging of TWPs. P-removing bacteria decreased (e.g., Burkholderia, Candidatus), while extracellular polymeric substance-secreting bacteria increased (e.g., Pseudomonas, Novosphingobium). Pearson correlation analysis highlighted EPFRs' role in TWPs' acute toxicity to microbial cells, yet, emphasizing particle size's impact on the sludge system's purification and community structure.

Changes in phosphorus-related performance attributes of dryland winter wheat cultivars released between the 1940s and 2010s in Shaanxi Province, China.

BACKGROUND: Water and nutrients are two main determinants of wheat yield, which are vital for maintaining high crop yields. In the present study, the effects of water and phosphate fertilization on wheat yield, photosynthetic parameters, water productivity and phosphate use efficiency were investigated. Five dryland wheat cultivars from the 1940s to the 2010s that are widely cultivated in Shaanxi Province, China, were used. Experiments were conducted from 2019 to 2022 using two irrigation levels (normal rainfall and no precipitation after the reviving stage) and two phosphorus application levels (0 and 100 kg ha-1). RESULTS: Compared with old cultivars ('Mazha'), the grain yield of modern cultivars ('Changhan 58') was 89.24% higher and was closely correlated with chlorophyll index, leaf area index, photosynthetic rate and tillers. With the replacement of cultivars, the phosphorus content, water potential and phosphatase activity of wheat leaves increased. Considering water-phosphorus interactions, the water use efficiency and phosphorus use efficiency of wheat showed a significant positive correlation. CONCLUSION: Our findings indicate that modern wheat cultivars are more responsive to phosphorus. Further analysis revealed that modern varieties have evolved two phosphorus absorption strategies in response to phosphorus deficiency - namely, the formation of a phosphorus supply source, which may result in larger numbers of green organs; and an increase in phosphorus sinks, which tended to activation and transport of plant phosphorus. Our results may thus contribute to water conservation, increased yields and the development of strategies for efficient phosphorus fertilization. © 2024 Society of Chemical Industry.

A comparative study on the effects of fungal and bacterial phytase with or without citric acid on growth performance, serum mineral profile, bone quality, and nutrient retention in broilers.

Objective: Current research aimed to compare the effects of fungal and bacterial phytase with or without citric acid (CA) on growth performance, serum mineral profile, bone quality, and nutrient retention in birds given non-phytate phosphorus (nPP)-deficient diets. Materials and Methods: A total of 216 Indian River broiler chicks were disturbed into six groups, namely, i) positive control (PC), ii) negative control (NC) contained 0.2% lower nPP than that in the PC diet, iii) NC + fungal phytase (Aspergillus niger), iv) NC + fungal phytase with 2% CA, v) NC + bacterial phytase (Escherichia coli), and vi) NC + bacterial phytase with 2% CA. Results: Compared to the PC group, the NC group showed poor performance, serum phosphorus (P) content, P retention, and bone quality. However, with the inclusion of phytase, all these phenomena were improved. The addition of bacterial phytase showed better values compared with fungal phytase. The main effects of phytase were significant for the feed conversion ratio (FCR), metabolizable energy conversion ratio (MECR), and P retention. The addition of CA, either with fungal or bacterial phytases, did not show considerable beneficial effects on overall performances. However, the main effects of CA were significant on the FCR, MECR, and crude protein conversion ratio. Conclusion: Incorporating bacterial and fungal phytase into low-nPP diets enhanced the broiler's performance. The effects of bacterial phytase were more apparent than those of fungal phytase. However, the efficacy of phytase based on the source might relate to dose, and other factors need further investigation.

A Flexible MXene-Black Phosphorus/Zinc Oxide Hybrid Structure with Excellent UVA-Specific Photoelectric Sensing Properties for Human Skin Protection.

Ultraviolet A (UVA) radiation causes various irreversible damages to human skin, so the research about UVA-specific sensing device is urgent. 2D black phosphorus (BP) is used in many photosensors due to its advantages of high carrier mobility and tunable bandgap, but its application for UVA-specific photosensor is not reported. Here, a MXene-BP/Zinc oxide (ZnO) hybrid structure with lamellar-spherical interfaces like finger lime fruit is prepared by the layer-by-layer assembly (LLA) method, and p-n junctions are constructed between BP and ZnO with the Ti3C2Tx electrode, showing excellent photoelectric performance. Density functional theory (DFT) calculations demonstrate that the enhanced performance is attributed to the rapid separation of photogenerated carriers in the presence of a built-in electric field at interface. Furthermore, a flexible MXene-BP/ZnO based UVA-specific photosensor is prepared, which shows a specific response to UVA as high as 7 mA W-1 and excellent mechanical stability, maintaining 98.46% response after 100 bending cycles. In particular, the integrated anti-UVA skin protection device shows excellent UVA-specific identification and wireless transmission capability, which can provide timely UVA exposure information and skin protection warning for the visually impaired. This work demonstrates a new approach for further developments of advanced photoelectric sensing technology toward improving people's skin health protection.

Challenges to extracting spatial information about double P dopants in Si from STM images.

The design and implementation of dopant-based silicon nanoscale devices rely heavily on knowing precisely the locations of phosphorous dopants in their host crystal. One potential solution combines scanning tunneling microscopy (STM) imaging with atomistic tight-binding simulations to reverse-engineer dopant coordinates. This work shows that such an approach may not be straightforwardly extended to double-dopant systems. We find that the ground (quasi-molecular) state of a pair of coupled phosphorous dopants often cannot be fully explained by the linear combination of single-dopant ground states. Although the contributions from excited single-dopant states are relatively small, they can lead to ambiguity in determining individual dopant positions from a multi-dopant STM image. To overcome that, we exploit knowledge about dopant-pair wave functions and propose a simple yet effective scheme for finding double-dopant positions based on STM images.

In-situ polymerization of phosphorus/nitrogen flame-retardant coating for polyester/cotton blend fabrics with superior durability.

The durable flame-retardant functional coating of polyester/cotton (T/C) blend fabrics is both interesting and challenging. In this study, a novel in-situ polymerization strategy for phosphorus/nitrogen-based flame-retardant on T/C blend samples was developed through the polycondensation of tetramethylolphosphonium sulfate, dicyandiamide, and anionic cyclic phosphate ester. The chemical structure of the polycondensation compounds, as well as the surface morphology, combustion behavior, flame-retardant capacity, washing durability and flame-retardant mechanism of the coated T/C blend fabrics, were investigated. The coated T/C blend fabrics demonstrated excellent self-extinguishing performance, with the damaged length decreasing to as low as 8.0 cm and the LOI reaching 28 %. Moreover, the peak heat release rate of the coated T/C blend fabrics decreased by 39.7 %. The superior flame retardancy can be attributed to the enhanced dehydration and carbonization by phosphate groups in the condensed phase, as well as the quenching effect and diluting effect in the gas phase. Additionally, the coated T/C blend fabrics exhibited remarkable washing durability and still achieved self-extinguishing after 65 washing cycles, and the in-situ deposition of insoluble three-dimensional polycondensation compounds onto the T/C blend fabrics was beneficial. The flame-retardant coating had a minor impact on the whiteness, tensile strength and breathability of the T/C blend fabrics.

CAMKK2-AMPK axis endows dietary calcium and phosphorus levels with regulatory effects on lipid metabolism in weaned piglets.

BACKGROUND: In the realm of swine production, optimizing body composition and reducing excessive fat accumulation is critical for enhancing both economic efficiency and meat quality. Despite the acknowledged impact of dietary calcium (Ca) and phosphorus (P) on lipid metabolism, the precise mechanisms behind their synergistic effects on fat metabolism remain elusive. RESULTS: Research observations have shown a decreasing trend in the percentage of crude fat in carcasses with increased calcium and phosphorus content in feed. Concurrently, serum glucose concentrations significantly decreased, though differences in other lipid metabolism-related indicators were not significant across groups. Under conditions of low calcium and phosphorus, there is a significant suppression in the expression of FABPs, CD36 and PPARγ in the jejunum and ileum, leading to inhibited intestinal lipid absorption. Concurrently, this results in a marked increase in lipid accumulation in the liver. Conversely, higher levels of dietary calcium and phosphorus promoted intestinal lipid absorption and reduced liver lipid accumulation, with these changes being facilitated through the activation of the CAMKK2/AMPK signaling pathway by high-calcium-phosphorus diets. Additionally, the levels of calcium and phosphorus in the diet significantly altered the composition of liver lipids and the gut microbiota, increasing α-diversity and affecting the abundance of specific bacterial families related to lipid metabolism. CONCLUSION: The evidence we provide indicates that the levels of calcium and phosphorus in the diet alter body fat content and lipid metabolism by modulating the response of the gut-liver axis to lipids. These effects are closely associated with the activation of the CAMKK2/AMPK signaling pathway.

Reutilization of post-adsorption lanthanum-loaded straw alleviates phosphorus pollution in rice-wheat system: Subsequent performance and underlying mechanisms.

Adsorption technology for phosphorus (P) removal is considered promising and reutilization of post-adsorbent can contribute to promoting sustainable agricultural production. However, the long-lasting impact of the post-adsorbent on crop growth and P remains unclear. This study assessed the effects of P-adsorbed lanthanum-modified straw (La@straw-P) on the rice yield, P fractionation and associated water quality parameters. The findings indicated that, compared with traditional fertilizer regimes, La@straw-P expedited the P reduction in the flooding water achieving a rate of decline to the tertiary standard for surface water (0.20 mg/L) 3.8 times faster and enhanced increased the P harvest index by 17.00 %. Economic estimation proved the positive benefits of La@straw-P in planting-breeding combination system. Redundancy analysis (RDA) and co-occurrence network analysis (CONA) revealed that electrical conductivity (EC) and dissolved Fe played primary roles in regulating total P. Fourier transform infrared spectra (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), and soil P fractions collectively demonstrated that the abundant adsorption sites on La@straw-P could facilitate the transformation of active P into moderately Ca-bound P. This study proposes a strategy for recycling P-adsorbed materials to mitigate agricultural non-point P pollution.

Serum phosphorus levels associated with nigrostriatal dopaminergic deficits in drug-naïve Parkinson's disease.

INTRODUCTION: A major component of Lewy bodies is phosphorylated α-synuclein. This post-translational modification of α-synuclein, phosphorylation, may consume a great amount of serum phosphorus. We aimed to investigate serum phosphorus levels and their associations with clinical phenotype and the degeneration of cardiac sympathetic and nigrostriatal dopaminergic neurons in patients with Parkinson's disease (PD). MATERIALS AND METHODS: We examined serum phosphorus levels in 127 participants (drug-naïve PD, 97; age- and sex-matched controls, 30). Associations of serum phosphorus levels with clinical features, heart-to-mediastinum (H/M) ratio on cardiac 123I-metaiodobenzylguanidine scintigraphy and striatal specific binding ratio of 123I-2-carbomethoxy-3-(4-iodophenyl)-N-(3-fluoropropyl) nortropane (123I-FP-CIT) were examined. RESULTS: Serum phosphorus levels were 3.4 ± 0.5 mg/dL in patients with PD and were not different from those in controls after controlling for age and sex (p = 0.850). Serum phosphorus levels were significantly lower in patients with PD and decreased H/M ratio than in those with PD and normal H/M ratio (3.3 ± 0.4 mg/dL vs. 3.6 ± 0.5 mg/dL, p = 0.003). Lower serum phosphorus levels were significantly associated with more severe degeneration of nigrostriatal dopaminergic neurons in patients with PD and decreased H/M ratio. However, this association was not observed in patients with PD and normal H/M ratio. CONCLUSIONS: Serum phosphorus levels and their association with nigrostriatal dopaminergic degeneration are different between patients with decreased H/M ratio and those with normal H/M ratio. Serum phosphorus levels may reflect the degree of nigrostriatal dopaminergic degeneration in patients with decreased H/M ratio, namely, Body-First PD.

Phosphorus attenuation and mobilization in sand filters treating onsite wastewater.

The effectiveness of phosphorus (P) removal by sand filters is limited during septic tank effluent (STE) treatment. The elevated effluent P concentrations pose threats to drinking water quality and contribute to eutrophication. The concern of P leaching from sand filters is further exacerbated by the increased frequency of flooding and natural precipitation due to climate change. This study aimed to understand P attenuation and leaching dynamics, as well as the removal mechanisms in sand filters treating STE, offering insights into the design and implementation of P removal/recovery modules to onsite wastewater treatment systems. P attenuation and leaching during STE treatment and rainfall were studied in bench-scale columns (new vs. aged sand). At standard STE loading (1.2 gallon d-1 ft-2), 24-32% removal of total phosphorus (TP) was achieved, while increased P removal efficiency (35-53%) was observed at low loading (0.6 gallon d-1 ft-2) with influent containing 10.3-20.0 mg P L-1. Complete breakthrough was observed in both aged (12-70 days) and new columns (27-73 days) at test hydraulic loadings. The maximum TP attenuation level was 20.6-45.3 mg P kg-1 and 25.3-33.0 mg P kg-1, in aged and new sand columns, respectively. When simulated rain was applied (15-60 mm h-1), 80-97% of the attenuated P leached out and the leaching dynamics were impacted by rainfall duration rather than the intensity. The highest concentrations of TP (15.6-15.9 mg L-1) were leached out from both columns within the first 2-6 hours. Orthophosphate was the dominant P species in treated effluent (83-84%) and leachate (69-88%), demonstrating its significance as the major P form in the discharge. In addition, aged sand (>5 years) accumulated higher levels of Mg, Al, Ca, and Fe, thus enhancing the P attenuation level during STE treatment. Collectively, this study underscored the importance of frequent field monitoring for reliable long-term P removal estimates.

Combined use of arbuscular mycorrhizal fungi and alkaline lignin enhance phosphorus nutrition and alleviate cadmium stress in lettuce (Lactuca sativa L.).

The excessive application of phosphorus (P) fertiliser and its poor utilisation efficiency have led to significant amounts of P being retained in agricultural soils in unavailable forms. The application of alkaline lignin to soil and its inoculation with arbuscular mycorrhizal fungi (AMF) have both been shown to improve plant P nutrition. However, their combined effects on soil P transformation remain unclear, particularly in cadmium (Cd)-contaminated soils. A potting experiment was conducted to examine the combined effects of AMF and alkaline lignin on soil P and Cd bioavailability and on the uptake of P and Cd by lettuce (Lactuca sativa L.) that were grown for 56 d in a growth chamber. Combined AMF and alkaline lignin treatment increased soil P availability and alkaline phosphatase activity. It furthermore increased bioavailable Cd concentrations of rhizosphere and bulk soils by 48 % and 72 %, respectively, and the Cd concentration in roots by 85 %, but the Cd concentration was not affected in the edible parts (shoots) of the lettuce. Moreover, the combined treatment increased shoot biomass by 26-70 % and root biomass by 99-164 %. Our findings suggested that the combined use of AMF and alkaline lignin mobilised both P and Cd in soil but did not increase the accumulation of Cd in the shoots of plants growing in Cd-contaminated soils, these results would provide guideline for increasing Cd tolerance of plants and their yield.

The concentration of organic nitrogen in mountain lakes is increasing as a result of reduced acid deposition and climate change.

The ionic and nutrient composition of mountain lakes recovering from atmospheric acidification is increasingly influenced by climate change (increasing air temperature and frequency of heavy rainfall events). We investigated the evolution of organic nitrogen (ON), dissolved organic carbon (DOC) and phosphorus (P) concentrations in alpine lakes in the Tatra Mountains (Central Europe) between 1993 and 2023, resulting from changes in climate and the ionic composition of atmospheric deposition. Our results suggest that the decreasing acidity of precipitation and the climatically induced increasing frequency of heavy rainfall events and air temperatures fluctuating around the freezing point have the potential to increase ON concentrations in alpine lakes despite decreasing deposition of inorganic N. The increasing ON involves its allochthonous and autochthonous sources: (1) increased co-export of ON with DOC from soils in dissolved organic matter due to less acidic precipitation and more frequent heavy rainfall events and (2) increased in-lake primary productivity (chlorophyll a) associated with higher P availability. Based on our previous studies, we hypothesize that P availability has increased due to (i) reduced adsorption of phosphate in precipitation to the metal hydroxides in the soil-adsorption complex as a result of increasing pH in precipitation and soil water and (ii) increased P production by weathering due to climate-induced increased mechanical erosion of rocks in unstable scree areas. The extent of these changes was related to the percentage cover of scree areas and meadow soils in the lake catchments. In addition, our results suggest that ON (besides chlorophyll a) may be a more sensitive indicator of increasing productivity of oligotrophic alpine lakes under changing air pollution and climate than generally low P concentrations and their poorly detectable trends.

A broadband modulator based on graphene/black phosphorus heterostructure with enhanced modulation depth.

We theoretically present a broadband modulator based on graphene/black phosphorus heterostructure which can work over a large waveband from visible (VIS) to mid-infrared (MIR) regions. By utilizing the angle dependence of black phosphorus, surface plasmon polaritons (SPP) modulation can be achieved in VIS regime, while the wavelength is tuned within the near-infrared (NIR) or MIR regions, the enhanced modulation depth can be achieved by few-layer graphene films. Results show that the proposed plasmonic modulator exhibits a broad waveband from 400 nm to 3 µm. In addition, this proposed modulator features high modulation depth (MD), low insertion loss (IL), large 3-dB modulation bandwidth and small power consumption from VIS to MIR regions. Our work may extend the operation waveband of opto-electro devices based on the hybridized 2D materials and would promote their potential future applications.

Assessing the effectiveness of indigenous phosphate-solubilizing bacteria in mitigating phosphorus fixation in acid soils.

Phosphorus (P) is the key to several structural molecules and catalyzes numerous biochemical reactions in plant body besides its involvement in energy transfer. Any deficit in P availability is likely to result in reduced RNA and protein content, inhibiting crop growth and development. Thus, availability of soil P is extremely crucial for plant growth especially in acid soils of India, where most of the fraction is bound to solid phase rendering their availability. The present communication deals with the isolation of elite phosphate-solubilizing bacterial (PSB) strains from the acid soils to work out their ability to improve the fertilizer P use efficiency in the acidic environment. Initially twenty-six bacteria were isolated from the acid soils of Northeastern India. Among them, ten bacteria were selected based on formation of halo zone in the Pikovskaya agar plate. In addition, these bacteria were able to solubilize insoluble zinc (Zn) and potassium (K). The isolates were subject to in vitro optimization for P solubilization under different insoluble P source utilization and at different pH and salinity conditions. Strains AN3, AN11, and AN21 exhibited significant solubilization of insoluble P, Zn, and K, and were identified as Streptomyces sp., Enterobacter sp., and Paraburkholderia caribensis. These three bacteria solubilized 206.53 to 254.08 µg mL-1 P, 79.7 to 177.55 µg mL-1 Zn, and 0.96 to 1.56 µg mL-1 K from insoluble minerals. Their performance was further evaluated in pot culture experiment using green gram as test crop. These three bacteria were found to improve P uptake and dry matter accumulation in green gram plant substantially. Seed bio-priming with the PSB strains enhanced the efficiency of added P fertilizer, resulting in a 1.40 to 1.52 times higher effectiveness compared to the control. On the whole, AN11 may be ranked as best inoculant for the acidic soils of Northeastern India. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-04042-2.

Suspended particulate matter in the Gulf of Oman: Spatial variations in concentration, bulk composition, and particulate metals controlled by physical and biogeochemical processes.

The present work aims to assess the biogeochemical and physical sources of variation in the spatial distribution of suspended particulate matter (SPM), its major biotic and abiotic components, particulate metals, and the Redfield (N:P) stoichiometry of particles in a poorly understood basin of the Gulf of Oman. Particulate samples were collected in February 2022 from the Gulf of Oman aboard the R/V Persian Gulf Explorer, revealing surface SPM concentrations ranging from 140 to 1145 µg/l. The elemental composition of crustal-type elements in the surface offshore region confirmed the input of lithogenic components by aeolian dust from the surrounding deserts. The highest mid-depth SPM levels, with remarkable contribution from CaCO3, were observed at the western shelf edge at 100-300 m depth, supported by the Persian Gulf outflow. Conversely, mid-depth maxima with elevated concentrations of terrigenous elements were observed in the eastern edge, emanating from sediment resuspension and lateral transport under eddy-topography interaction. Organic matter is the most important phase, followed by biogenic silica from the basin-wide winter bloom of diatoms. While signs of CaCO3 dissolution are evident at depths >500 m, the oxidative precipitation of Mn (II) in the upper boundary of the oxygen minimum zone leads to the appearance of perceptible maxima in the vertical profile of particulate MnO2. Seasonal variations in the organic N:P ratio, from summer to winter, at the western station were linked to shifts in phytoplankton assemblage structure, transitioning from cyanobacteria dominance in summer to chain-forming diatoms in winter. The particulate pool of biologically important trace metals was dominated by a non-crustal fraction with enrichment factor followed a descending order: Cd > Mo > Pb > Zn > Ni in surface offshore samples. Metal/P ratios comparison with some previous data from the open ocean SPM and lab cultures of phytoplankton reveals that the Zn/P ratio is significantly exceeded in cultured communities, whereas the Cd/P ratio reflected the consistent demand in the Gulf of Oman compared to reported lab culture requirements.

TaMYB-CC5 gene specifically expressed in root improve tolerance of phosphorus deficiency and drought stress in wheat.

Phosphate deficiency and drought are significant environmental constraints that impact both the productivity and quality of wheat. The interaction between phosphorus and water facilitates their mutual absorption processes in plants. Under conditions of both phosphorus deficiency and drought stress, we observed a significant upregulation in the expression of wheat MYB-CC transcription factors through the transcriptome analysis. 52 TaMYB-CC genes in wheat were identified and analyzed their evolutionary relationships, structures, and expression patterns. The TaMYB-CC5 gene exhibited specific expression in roots and demonstrated significant upregulation under phosphorus deficiency and drought stress compared to other TaMYB-CC genes. The overexpression of TaMYB-CC5A in Arabidopsis resulted in a significant increase of root length under stress conditions, thereby enhancing tolerance to phosphate starvation and drought stress. The wheat lines with silenced TaMYB-CC5 genes exhibited reduced root length under stress conditions and increased sensitivity to phosphate deficiency and drought stress. In addition, silencing the TaMYB-CC5 genes resulted in altered phosphorus content in leaves but did not lead to a reduction in phosphorus content in roots. Enrichment analysis the co-expression genes of TaMYB-CC5 transcription factors, we found the zinc-induced facilitator-like (ZIFL) genes were prominent associated with TaMYB-CC5 gene. The TaZIFL1, TaZIFL2, and TaZIFL5 genes were verified specifically expressed in roots and regulated by TaMYB-CC5 transcript factor. Our study reveals the pivotal role of the TaMYB-CC5 gene in regulating TaZIFL genes, which is crucial for maintaining normal root growth under phosphorus deficiency and drought stress, thereby enhanced resistance to these abiotic stresses in wheat.

Simultaneous aerobic nitrogen and phosphorus removal by novel halotolerant fungus Mucor circinelloides SNDM1: Function and metabolism pathway.

Fungi capable of simultaneous nitrogen and phosphorus removal from wastewater is rarely found. Here, a novel fungal strain (SNDM1) performing heterotrophic nitrification, aerobic denitrification, and phosphate removal was isolated and identified as Mucor circinelloides. The favorable nutrient removal conditions by the strain using glucose were C/N ratio of 25-30, salinities of 0 %-3 %, and pH of 7.5. Strain SNDM1 achieved ammonium, nitrite, nitrate, and phosphate removal rates of 5.23, 10.08, 4.88, and 0.97 mg/L/h. Nitrogen balance indicated that gaseous (18.60 %-24.55 %) and intracellular nitrogen (43.76 %-70.63 %) were primary fate of initial nitrogen. Enzyme activity revealed that ammonium removal occurred through heterotrophic nitrification and aerobic denitrification. Removed phosphorus was mainly transformed into cell membranes (56 %-64 %) and extracellular polymeric substances (20 %-26 %). Orthophosphate was the major intracellular phosphorus species, while polyphosphate and pyrophosphate existed extracellularly. These findings highlight the potential of this fungal strain for bioremediating polluted wastewater.

Nacre-Inspired Structure Enables Ultrahigh "Strong-Tough" Design of Phosphorus Anode.

Red phosphorus anode, attributed to its high specific capacity of 2596 mAh g-1, is expected to improve the energy density of Na-ion batteries. However, the P anode currently is unsatisfactory for practical usage due to the large volume expansion beyond 300%, which brings out uncontrolled brittle failure. To address this challenge, we here design a nacre-like phosphorus anode by resilient graphene oxide staggered together. The staggered structure simultaneously offers mechanical strength and interwoven toughness. Finite element modeling reveals that the sodiation stress from P nanoparticles will be transferred into interlayer pillars as the elastic medium to release sodiation stress. The prepared anode achieves an ultrahigh areal capacity of 13 mAh cm-2 at a mass loading of 5.8 mg cm-2. Notably, the volume change of the anode is limited to approximately 8.2% at full sodiation, significantly lower than that of the traditional phosphorus electrodes.