The impact of riparian wetlands on the cycling, retention and export of nutrients from land to water varies according to local environmental conditions and is poorly resolved in catchment management approaches. To determine the role a specific wetland might play in a catchment mitigation strategy, an alternative approach is needed to the high frequency and spatially detailed monitoring programme that would otherwise be needed. Here, we present a new approach using a combination of novel and well-established geochemical, geophysical and isotope ratio approaches. This was developed and tested against a 2-year high-resolution sampling programme in a lowland permeable wetland in the Lambourn catchment, UK. The monitoring programme identified multiple pathways and water sources feeding into the wetland, generating large spatial and temporal variations in nutrient cycling, retention and export behaviours within the wetland. This complexity of contributing source areas and biogeochemical functions within the wetland were effectively identified using the new toolkit approach. We propose that this technique could be used to determine the likely net source/sink function of riparian wetlands prior to their incorporation into any catchment management plan, with relatively low resource implications when compared to a full high frequency nutrient speciation and isotope geochemistry-based monitoring approach.

River sediment from two inflow watersheds (Hongze and Tiaoxi) to Hongze and Taihu Lake in Eastern China was analyzed by the sequential extraction procedure. This study aimed to explore a spatial distribution of phosphorus fractions in river sediments and analysed the relationship between different phosphorus fractions and their environmental influence on the sediments within different watersheds in Eastern China. Five fractions of sedimentary phosphorus, including freely sorbed phosphorus, were all analyzed (NH₄Cl-P), redox-sensitive phosphorus (BD-P), bound phosphorus metal oxide (NaOH-P), bound phosphorus calcium (HCl-P) and residual phosphorus (Res-P). The order of rank of the P fractions for the river Anhe was HCl-P>NaOH-P>BD-P>NH₄Cl-P; whereas that of the Suihe river was HCl-P>BD-P>NaOH-P>NH₄Cl-P. For the rank order of the Hongze watershed, HCl-P was higher while the NH₄Cl-P contents were significantly lower. The rank order for the Dongtiaoxi river was NaOH-P > HCl-P> BD-P> NH₄Cl-P and that of Xitiaoxi river was NaOH-P> BD-P> HCl-P> NH₄Cl-P. Compared with phosphorus forms of Tiaoxi watershed, NaOH-P contents were significantly higher in the converse of HCl-P contents were significantly higher in Hongze watershed while both in NH₄Cl-P contents were significantly lower. Variations may be attributed to differential discharge of P watershed form due to land-use changes and urban river ambient conditions.

Phosphorus (P) concentration in rivers and lakes receives greater attention due to its significance in contributing to eutrophication. This study aimed at profiling phosphorus species in Vembanad lake (Ramsar site) and its adjoining rivers. Four phosphorus fractions (total reactive phosphorus (TRP), total acid hydrolysable phosphorus (TAHP), total organic phosphorus (TOP) and total phosphorus (TP)) were monitored according to premonsoon and postmonsoon seasons. Meenachil river mouth is a hotspot for eutrophication with high values of most of the phosphorus fractions. Among the four fractions TRP, TOP and TP were recorded maximum concentration during the premonsoon and postmonsoon seasons. Each fraction of TRP, TAHP, TOP, and TP had an average concentration of more than 300 µgL-1 P throughout two seasons, which is highly eutrophic. The result reveals that the surface water of Vembanad lake is highly polluted with phosphorus input and it may trigger algal growth and consequent destruction of the biodiversity rich wetland system.

Abstract The processing of anatase ores by sulfuric acid digestion is well known for its low titanium dissolution yields, which makes the process economically and technically unfeasible. Generally, to enhance the dissolution of titanium from anatase, thermal processes along with acid and/or alkaline leaching are necessary. Few existing works report yields of direct digestion of anatase with sulfuric acid <48%. This study investigated the sulfuric digestion of anatase and yields around 80% were obtained at relatively mild conditions such as temperature at 220°C, sulfuric acid/concentrate ratio of 1:2 and 3 hours of reaction. A comprehensive characterization of anatase ore was also presented.

Crop production in Afghanistan suffers from limited phosphorus (P) availability, which severely hinders national agriculture sustainability. This present study hypothesized that deep fertilizer placement could significantly enhance uptake of immobile P and thus tissue P accumulation and crop yield. A two-year pot experiment growing two maize (Zea mays) hybrid cultivars (Xida-789 and Xida-211) was therefore conducted to test these hypotheses under three contrasting fertilizer placement methods (broadcast, side band, and deep band). In doing so, P concentrations in both maize tissues and soils were compared at 45, 60, and 115 days after sowing (DAS) under nine combinations of nitrogen (N) and P fertilizer rates (kg ha-1: N112P45, N112P60, N112P75, N150P45, N150P60, N150P75, N187P45, N187P60, N187P75). Results have shown that deep band placement significantly increased P uptake efficiency, leading to greater P concentration and accumulation in maize tissues compared to other two fertilization methods. This improved P uptake was attributed to several factors associated with deep placement, including reduced P fixation, enhanced root access to P, and moisture availability for P uptake. Additionally, deep band placement combined with higher N application rates (N187 and N150) further enhanced plant P uptake by promoting P availability and utilization mechanisms. Deep band placement also resulted in significantly higher total soil P, Olsen-P, and P use efficiency than broadcast and side band methods, indicating a more efficient P fertilization strategy for maize that can improve growth and yield. This present study also found positive correlations between P concentration in plant organs and soil Olsen-P, highlighting the importance of adequate soil P levels for optimal plant growth. Overall, our results have showed that deep band fertilizer placement emerged as a superior strategy for enhancing P uptake efficiency, utilization, and maize productivity compared to broadcast and side band placement. This approach can potentially optimize P fertilizer utilization, improve maize growth and yield, while minimizing environmental P losses associated with broadcast applications.

Phosphorus (P) is the second-most important element after nitrogen that is required for plant growth. Although this element is abundant in most soils, it is rarely available in plant-accessible forms since most of it normally exists in soil in insoluble forms such as phosphates. In conventional agriculture, P is normally supplied as chemical fertilizer to satisfy plant P requirements. This, to a large extent, boosts plant production. However, chemical fertilizers are costly, have a huge carbon footprint, and are environmentally-unsustainable owing to the high energy requirements during their synthesis. Besides, P-containing agricultural run-offs contribute hugely to the eutrophication of water bodies and environmental degradation. Moreover, plants can consume only a small amount of chemically-supplied P since between 75 and 90% of this form of P normally get precipitated into complexes and rapidly become fixed in soil. These issues and concerns necessitate research into alternative and viable ways of supplying P to plants. Rhizobacteria have for decades been investigated in vivo and in planta as suitable tools in sustainable agriculture due to the plant-growth-promoting activities such as nutrients’ solubilization, nitrogen fixation, and production of phytohormones. Although a lot of research has been done on different nutrients-solubilizing rhizobacteria and their potential in sustainable agriculture, their mechanisms of action and prospects in sustainable agriculture remain to be fully understood. This review particularly focuses on the P solubilizing rhizobacteria and evaluates their diversity, mechanisms of action, and prospects in sustainable agriculture based on the present and future scenario of their application. Such information is useful in determining their potential and evaluating their prospects in promoting sustainable agricultural systems.

This paper presents a comprehensive cost-benefit analysis of producing alternative phosphorus (P) fertilizers from recycled water treatment residuals (Fe-WTR) and cowshed effluents, under the umbrella of circular economy approach. Fe-WTR is compared to a synthetic adsorbent, layered double hydroxide (LDH). Dairy wastewater is used as a P source for both adsorbents. The cost of 1 ton P-Fe-WTR sums up to 329 Euro. In contrast, the use of synthetic adsorbents (P-LDH) incurs significantly higher costs, amounting to 3329 Euros per ton, underscoring the economic advantage of utilizing waste-derived materials. Adopting Fe-WTR fertilizer not only offers substantial cost savings by avoiding landfill fees (40-150 Euros per ton) and wastewater discharge fines (500 Euros per ton) but also reduces environmental impacts. This sustainable method mitigates eutrophication and pollution, presenting a dual benefit of cost-effectiveness and environmental protection. Although our results are based on a specific case study, they reflect the potential value of extending the circular economic approach to P production worldwide: Recycling P from waste streams can be economically viable and environmentally preferable at large, aligning with global sustainability goals and demonstrating the practicality of circular economy principles in environmental management.

The aim of this paper was to determine the soil phosphorus release risk from drained and re-wetted peatlands under different landcovers. The study was carried out at 10 soil profiles (organic soils, frequently with mursh in the topsoil, developed from low peat with various degrees of decomposition, on mineral subsoil or gyttja) located south-west of Lake Kośno nature reserve in northern-central Europe (north-eastern Poland). The soil samples were collected from the depths of 0-30 cm, 50-80 cm and 100-130 cm during spring, summer and autumn (in April, July, and October). In the laboratory, the following soil properties were determined: ash content, soil reaction, content of total organic carbon, total nitrogen, total and plant-available phosphorus. Gyttja formations and hemic peats had the highest total P content (6.77 g∙kg-1 and 2.29 g∙kg-1, respectively). Murshes contained twice less P (1.18 g∙kg-1). In spring, more plant-available phosphorus (AP sp) was released in murshes (0.29 g∙kg-1) than in peats (0.07-0.14 g∙kg-1). In the summer, higher amounts of plant-available P were stated in fiber peats (0.37 g∙kg-1) than in murshes (0.26 g∙kg-1), whereas in autumn, the amounts of P in murshes (0.22 g∙kg-1) and peats (0.21-0.23 g∙kg-1) did not vary. Generally, average contents of AP were the highest in murshes (0.26 g∙kg-1) and fiber peats (0.25 g∙kg-1), and the lowest in sapric peats (0.15 g∙kg-1). The release of phosphorus from organic compounds or binding of P by organic matter (immobilization) depends on the C:P ratio in plant residues and soil. If it is wide (&gt;300), P is bound, if it is narrower (150–200), P is released. In the tested soil formations, the C:P ratio was frequently above 300. Only in some murshes and gyttjas the C:P ratio was below 150, which may indicate a risk of phosphorus release to groundwaters.

The present contribution provides the first agro-economic and ecological account of the in-furrow application of a mineral and an organomineral microgranular fertilizer in comparison to a wide spread mineral band fertilizer in temperate climate regions. The reduction of phosphorus inputs while maintaining the yield of maize plants (Zea mays) is the focus of the study. In a three-year field trial, the dry matter yields gained with the two phosphorus-reduced microgranular fertilizers and standard diammonium phosphate (DAP) fertilization were examined. The application of the organomineral microgranular fertilizer resulted in dry matter yields that were 15% higher (2.8 tons per hectare) than the DAP variant, while higher yields using the mineral microgranular fertilizer occurred only in a single year. The higher yield of the organomineral microgranular fertilizer and the lower phosphorus amounts applied with that product resulted in a moderate phosphorus excess of 2.7 kg P ha-1, while DAP fertilization resulted in a surplus of 25.5 kg per hectare. A similar pattern of phosphorus balance was observed on the plots fertilized with the mineral microgranular fertilizer. We conclude that both tested microgranular fertilizers provide an adequate alternative to the wide-spread DAP fertilization in maize cultivation on fertile soils.

Floodplains are critically important ecosystems that provide a whole suite of ecosystem services including nutrient and carbon sequestration, flood mitigation, water storage, and critical wildlife habitat to name a few. However, human modification of rivers and floodplains through channelization, artificial levee construction, reduction in active floodplain area, and water management can significantly reduce the ecosystem function of river-floodplain systems. In this study, we evaluated the changes in nutrient loading of the Kissimmee River floodplain during the restoration of the river-floodplain system. In addition to time-series loading analysis, we also evaluated soil nutrient concentrations across the lower portion of the Kissimmee River floodplain. During the 44-year nutrient loading time-series, the floodplain remained a nutrient exporter with changes in nutrient loading generally corresponding to both water quality (i.e. point source reductions) and hydrologic restoration activities in the watershed and Kissimmee River floodplain. During the study period, inputs of total phosphorus and total nitrogen loads from upstream either significantly increased or remained the same. In addition to external sources of nutrients, internal sources of nutrients from floodplain soils can also contribute to the total nutrient export from the system. These internal sources could be organic via the decomposition of organic matter or geologic from the original excavation of the canal and/or restoration backfilling. Soil nutrient concentrations vary between vegetative communities and landscape position and could be a significant source of phosphorus to the downstream system which is plagued by eutrophic conditions. Therefore, as floodplain function in the Kissimmee River continues to be restored and managed, additional effort may be needed to address nutrient inputs and internal legacy nutrients.

Legislation and interest to protect and restore freshwater and marine ecosystems from aquaculture's environmental impact is global. However, aquaculture induced eutrophication continues to be a major environmental issue. Open freshwater fish farms in particular, providing fish with phosphorus-rich feeds pollute aquatic ecosystems since water soluble phosphorus, uneaten feed, feces, and metabolic waste from farmed fish increase phosphorus concentration in the adjacent waters. Several intestinal enzymes, transporters, and regulating factors are implicated in dietary phosphorus retention of farmed fish. For example, alkaline phosphatase and other transporters help the anterior intestine absorb phosphorus, while pH, calcium, and vitamin D affect these enzymes and transporters. Intestinal morphology and gut microbiome may also affect this process. Reducing phosphorus pollution from open-flow fish farms requires a thorough understanding of processes that affect nutrient retention and absorption as well as of the impact of dietary factors, anti-nutritional substances, and intestinal morphology. Optimizing feed composition, adding functional feed ingredients, and managing gut health can reduce phosphorus release and improve aquaculture sustainability. Processing and functional feed additives can mitigate anti-nutritional factors and, addressing these issues will reduce aquaculture's environmental impact, ensuring aquatic ecosystem health and global food security

Microalgae are naturally adapted to fluctuating availability of phosphorus (P) being capable to opportunistically uptake large amounts of inorganic phosphate (Pi) and safely store it in the cell as polyphosphate. Hence, many microalgal species are remarkably resilient to high concentrations of external Pi. Here we report on an exception from this pattern comprised by a failure of the high Pi-resilience in a strain Micractinium simplicissimum IPPAS C-2056 normally coping with a very high Pi concentrations. This phenomenon occurred after abrupt re-supplementation of Pi to the M. simplicissimum culture pre-starved of P. This was the case even if Pi was re-supplemented in a concentration far below the level toxic to the P-sufficient culture. We hypothesize that this effect can be mediated by a rapid formation of the potentially toxic short-chain polyphosphate following the mass influx of Pi into the P-starved cell. A possible reason for this is that the preceding P starvation impairs the capacity of the cell of converting the newly absorbed Pi into a “safe” storage form of long-chain polyphosphate. We believe that findings of this study can help to avoid sudden culture crashes, they are also of potential significance for development of algae-based technologies for efficient bioremoval of P from P-rich waste streams.

5-Methyl-3,8-di-(2-amino-4-bromophenyl)-4,9-dioxa-1,2,6,7-tetraaza-5λ5-phosphaspiro[4.4]nona-2,7-diene was obtained in a condensation reaction of 2-amino-5-bromobenzohydrazide and methylphosphonyl dichloride in the presence of triethylamine. An initial biological screening was performed for the obtained product. The synthesized compound possesses two aromatic primary amine groups and two bromine atoms within the structure, which are suitable for further structural modifications.

MicroRNAs (miRNAs) regulate plant growth and development and their responses to biotic and abiotic stresses. Although extensive studies show that miR159 family members regulate leaf and flower development in Arabidopsis thaliana, the roles of miRNAs in soybean (Glycine max) are poorly understood. Here, we identified six MIR159 genes in soybean, MIR159aMIR159f, and investigate their expression patterns in plants under low-phosphorus (low-P), NaCl, or abscisic acid (ABA) treatments. In soybean leaves, MIR159e and MIR159f expression was induced by low-P treatment, while in roots, MIR159b, MIR159c, MIR159e, and MIR159f expression was upregulated. In flowers, low-P led to upregulation of MIR159a, MIR159b, MIR159c, and MIR159f, but downregulation of MIR159d and MIR159e. In soybean nodules, MIR159b was upregulated but MIR159a, MIR159c, and MIR159d was downregulated under P deficiency. NaCl treatment induced MIR159a, MIR159b, MIR159c, and MIR159e expression in leaves, and MIR159aMIR159f expression in roots. ABA treatment upregulated MIR159a, MIR159b, and MIR159c but downregulated MIR159d, MIR159e, and MIR159f in leaves. These results suggest that miR159 family members function in plant abiotic stress responses. Moreover, total P content in leaves was significantly lower in plants overexpressing MIR159e than in the wild type, suggesting that miR159e may regulate P absorption and transport in soybean.

Alum sludge, an inevitable by-product from the water purification process, which had been applied as substrates in some constructed wetlands with good performance, especially for phosphorus (P) adsorption. The raw alum sludge is like clay lump with irregular shape and has a leaching concern used in the water. For a better reuse, herein, sludge was fired to produce alum sludge ceramsite (ASC) with a uniform spherical shape via four-step process of kneading sludge ball, air drying, preheating at 400°C for 10 min and firing at 600℃ for 5 min. Thereafter the physicochemical properties and P adsorption ability of ceramsite were investigated. Through XRD and FT-IR tests, there was no obvious difference between ASC and air-dried alum sludge ball (adASB) on the phase structure, but a certain amount of Al-OH group loss on the surface of ASC. The structure of ASC was still amorphous as same as adASB, while ASC possessed more micropore structure and bigger specific surface area than those of adASB. Adsorption experiments showed the P adsorption behaviors of ASC and adASB were much similar, and their adsorption kinetics all accorded with the two-step adsorption kinetics rate equation and pseudo-second-order kinetics equation. The maximum adsorption capacities of ASC and adASB fitted by Langmuir model were 1.66 mg/g and 1.89 mg/g respectively. It should be pointed that, compared with other adsorbents, ASC produced in this study still had a higher ability to adsorb P. Therefore, ASC should have a great application potential for P removal in the wastewater treatment in China.

Environmental legislation on waste management coupled with the potential for nutrients recovery are key factors encouraging the use of advanced treatment technologies to manage biosolids waste. In this context, phosphorus recovery from a sewage sludge treated by a wet oxidation process was carried out. High organic matter (up to 85% in COD) and Total Solids content (up to 75%) removal values were achieved at elevated temperature (up to 300 ºC) and pressure (up to 200 bar) conditions. The liquid and solid fractions found in oxidation process effluent contain amounts of phosphorus that can be recovered. This research aims to maximize its valorization in both liquid and solid fractions. In the liquid effluent, phosphorus was recovered (up to 90 mg P L-1) by chemical precipitation as struvite (MgNH4PO4∙6 H2O), a slow-release fertilizer. In this case, P recoveries greater than 95% were achieved. Also, the solid fraction, analyzed after filtration and drying (68 mg P gsolid-1), was treated by acid leaching, to achieve up to 60% phosphorus recovery. All phosphorus extracted was in orthophosphate form.

The introduction of organic and inorganic substances to the environment is a result of human activities such as agriculture, domestic and industrial wastewater which leads to pollution. Treatment processes of these wastewaters are being conducted globally to eliminate easily settled materials and recover nutrients in an attempt to release clear and apparently clean effluent into natural waters. Lack of removing inorganic nitrogen and phosphorus nutrients is the greatest cause of eutrophication in water bodies which inhibits the life of other organisms as well as pose a threat to human life and loss of the economy. Different technologies have been applied and are being developed to recover nutrients as well as heavy metals from wastewater to meet the permissible limits before discharging effluents. Wastewater treatment using microalgae offers an opportunity to provide tertiary bio-treatment and production of valuable biomass. Microalgae use the available inorganic nitrogen and phosphorus for their growth which are then harvested for various uses. Additionally, they have the ability to remove heavy metals and some toxic compounds. The main specific microalgae species in this study is the Chlorella sorokiniana with the Aequorea victoria jellyfish This paper reviews some of the wastewater treatment processes and focus on the use of microalgae and some of the shortcomings of the technologies and how they can be improved to achieve maximum nutrient recovery economically with low energy demand.

This study investigates the fabrication and optimization of Co-Fe-P catalysts on Cu foam using electroless deposition, focusing on their hydrogen generation efficiency. Deposition times were varied from 1 to 10 minutes, resulting in spherical Co-Fe-P particles growing from sub-micron to several microns in size. The optimal hydrogen generation rate of 27.66 ml/min was achieved with a 5-minute deposition. Extending the deposition to 10 minutes led to particle aggregation, reducing the efficiency per unit weight. The impact of bath temperatures from 30°C to 60°C was also assessed, with temperatures of 50°C and above promoting the development of larger 3D structures and increasing Fe and P contents (~9.3 wt.% and 10 wt.%). This enhanced hydrogen generation, peaking again at 27.66 ml/min. NaOH concentrations were varied from 0.5 M to 0.9 M, showing that concentrations over 0.8 M improved catalyst morphology and performance, increasing hydrogen generation to 10.03 ml/min. Among substrates tested, Co-Fe-P on Cu foam demonstrated the highest hydrogen generation rate due to better catalyst distribution and surface area. The study underscores the importance of deposition conditions and substrate choice in optimizing Co-Fe-P catalysts for hydrogen generation.

This study examines the potential of UiO-66 and g-C3N4-based composite catalysts for environmental purification and pesticide degradation. By integrating zirconium-based metal-organic framework UiO-66 with graphitic carbon nitride (g-C3N4), a composite with a Z-type heterojunction structure is created, enhancing photocatalytic pesticide degradation and phosphorus recovery. The optimal composite, UiO-66/g-C3N4(UG6:4), shows high efficiency in degrading organophosphorus pesticides like DDVP under visible light. This catalyst's high surface area and porous nature efficiently adsorb and break down persistent soil pollutants, including DDT and DDVP. Featuring robust stability and effective photocatalytic activity, the UiO-66/g-C3N4 composite holds promise for soil remediation and dealing with organic pollutants. Future research will aim to further refine this material’s structure and properties, ensuring its practical application in environmental cleanup.

Phosphorus (P) is an important and irreplaceable macronutrient. It is central to energy and information storage and exchange in living cell. P is an element with “broken geochemical cycle” since it lacks abundant volatile compounds capable of closing the P cycle. P fertilizers are critical for global food security, but the reserves of minable P are scarce and non-evenly distributed between countries of the world. Accordingly, the risks of global crisis due to limited access to P reserves is expected to be graver than those entailed by competition for fossil hydrocarbons. Paradoxically, despite the scarcity and value of P reserves, its usage is extremely inefficient: current waste rate reaches 80% giving rise to a plethora of unwanted consequences such as eutrophication leading to harmful algal blooms. Microalgal biotechnology comprise a promising solution to tackle this challenge. The proposed review briefly presents the relevant aspects of microalgal P metabolism such as cell P reserve composition and turnover, and the regulation of P uptake kinetics for maximization of P uptake efficiency with the focus on novel knowledge. Multifaceted role of polyPhosphates, the largest cell depot for P, is discussed with emphasis on the P toxicity mediated by short-chain polyPhosphates. Opportunities and hurdles of P bioremoval via P uptake from waste streams with microalgal cultures, either suspended or immobilized, is discussed along with the role of bacterial components of microalgal-bacterial consortia in these processes. Possible avenues of P-rich microalgal biomass such as biofertilizer production or extraction of valuable polyPhosphates and other bioproducts are considered. The review concludes with a comprehensive assessment of the current potential of microalgal biotechnology for ensuring the sustainable usage of phosphorus.

Soil enzyme activity can be affected by both production and degradation, as enzymes can be degraded by proteases. However, the impact of nutrient addition on enzyme activity is often solely attributed to changes in enzyme production without fully considering degradation. Here, we demonstrated that the activities of β-1,4-glucosidase (BG), β-D-cellobiohydrolase (CBH), β-1,4-Xylosidase (BX), and β-1,4-N-acetyl-glucosaminnidase (NAG) were comparable in nitrogen (N) and phosphorus (P) fertilized soils and the unfertilized control under field conditions, but the reduction in activity was substantially greater in the fertilized soils during short-term laboratory incubation. The results show that the interruption of the natural, continuous supply of organic matter or non-soil microbial-derived enzymes, which typically occurs under field conditions, leads to a more significant reduction in apparent enzyme activities in fertilized soils compared to unfertilized control. This may be attributed to the higher abundance of protease in fertilized soils, resulting in faster enzyme degradation. Interestingly, P fertilization alone did not have a similar effect, indicating that N fertilization is likely the main cause of the larger decreases in enzyme activity during incubation in fertilized soils compared to unfertilized control soils, despite our study site being poor in P and rich in N. These findings highlight the importance of considering enzyme degradation when investigating material dynamics in forest ecosystems, including the impact of nutrient addition on enzyme activity, as enzyme production alone may not fully explain changes in apparent enzyme activity.

Control of nutrients, mainly nitrogen (N) and phosphorus (P), plays a significant role in preventing cyanobacterial blooms (harmful algal blooms (HABs)). This study aimed at evaluating changes in the risk of the occurrence of cyanobacterial blooms and advancing the understanding of how N and P affect the growth of cyanobacteria in a eutrophic lake, Lake Vombsjön, in southern Sweden. Statistical analysis was used to demonstrate the pattern of cyanobacterial blooms, that the highest content present in September and the later that algal blooms occur, the more likely it is a cyanobacterial bloom as cyanobacteria became dominating in October and November (90%). Two hypothesises tested in Lake Vombsjön confirmed namely that a high total phosphorus (TP) level correlates with an abundance of cyanobacteria and that low N:P ratio (total nitrogen/total phosphorus < 20) favours the growth of cyanobacteria. To control the growth of cyanobacteria in Lake Vombsjön, the TP level should be kept below 20 µg/L and the N:P ratio be maintained at a level of over 20. The two species Planktothrix agardhii, and Pseudanabaena spp. should be carefully monitored especially in late autumn. Future work should consider any high degree of leakage from the sediment of the dissolved phosphorus available there.

Abstract. Results of research into four-membered phosphorus(V)-heterocycles, 2-halogen-1,2λ⁵-oxaphosphetanes are presented. The preparation of 2-halo-1,2λ⁵-oxaphosphetanes by reaction of P-haloylides with carbonyl compounds is described. The mechanism of asynchronous [2+2]-сycloaddition of ylides to aldehydes was proposed on the base of low-temperature NMR investigations. 2-Halogen-1,2λ⁵-oxaphosphetanes were isolated as individual compounds and their structures were confirmed by ¹Н, ¹³C, ¹⁹F and ³¹Р NMR spectra. These compounds are convenient reagents for preparing of various organic and organophosphorus compounds hardly available by other methods. Chemical and physical properties of the 2-halo-1,2λ⁵-oxaphosphetanes are reviewed. The 2-chloro-1,2λ⁵-oxaphosphetanes depending on substituents at the α-carbon atom rearrange with formation of 2-chloroalkylphosphonates or convert into trans-phosphorylated alkenes. Prospective synthetic applications of 2-halo-1,2λ⁵-oxaphosphetanes are analyzed. The 2-halo-1,2λ⁵-oxaphosphetanes may be easily converted to various alkenylphosphonates: allyl- or vinylphosphonates, phosphorus ketenes, thioketenes, ketenimines.

To achieve n-type doping in diamond, extensive investigations employing first principles have been conducted on various models of phosphorus doping and boron-phosphorus co-doping. The primary focus of this study is to comprehensively analyze the formation energy, band structure, density of states, and ionization energy of these structures. It is observed that within a diamond structure solely composed of phosphorus atoms, the formation energy of an individual carbon atom is excessively high. However, the substitution of two carbon atoms leads to the conversion of diamond into a p-type semiconductor. Upon examining the P-B co-doping structure, it is revealed that the doped impurities exhibit a tendency to form more stable cluster configurations. As the separation between the freely doped atoms and the cluster impurity structure increases, the overall stability of the structure diminishes, consequently resulting in an elevation of the ionization energy. Analysis of the electronic density of states demonstrates that the electron orbit of the B atom makes negligible contributions to the impurity levels during P-B doping.

A substantial amount of phosphorus (P) in soil is not readily available for plant uptake. Certain species may enhance P availability from poorly soluble P forms. This research aimed to compare the P solubilization capacity of the soil of two Lupine species, L. albus, and L. angustifolius, with a control crop of oats (Avena strigosa L.). Plants were planted in pots in four soils with varying texture, organic matter content, acidity, and P availability. Phosphorus solubilization capacity was assessed on variations of P availability (PBray1) at four points in time, comparing soils with lupine to oat-containing soils and their baseline values. At harvest, measurements of plant shoot biomass included their shoot dry weight and some nutrient concentrations such as P, nitrogen (N), manganese (Mn), and lupine nitrogen fixation. Compared to soils containing oats, lupine soils significantly increased PBray1 concentrations; increments ranged from 0.9 to 5.4 mg kg-1, depending on species, sampling time, and soil type. Lupine-induced soil acidification did not fully explain this P increase., As a proxy measurement of organic acid exudation, Manganese concentration was high in both lupine species' shoot biomass; however, these legumes had divergent Mn accumulation responses to soil acidity and P availability. Nitrogen fixed quantity varied with Lupine species (105-240 mg pot-1) and soil type (60-240 mg pot-1). Lupinus albus had a higher ability to mobilize non-labile P and provide N through biological N fixation (BNF), positioning it as a suitable crop for diversifying Uruguay's agricultural crop rotation systems.

'Huangguan' pear has significant social and economic value, and phosphorus, as one of the three main mineral elements of plants, has an irreplaceable effect on the normal growth of 'Huangguan' pear trees. The objective of this study was to predict the content of phosphorus in the pulp and peel of ‘Huangguan’ pears nondestructively and conveniently by using near-infrared spectroscopy (900–1700 nm) technology. First, twelve algorithms are used to preprocess the original spectral data, and the partial least squares regression algorithm and the gradient boosting regression tree algorithm are used to build a full-band prediction model based on the original spectral data and the processed spectral data. The characteristic wavelengths were extracted using genetic algorithms, followed by establishing a characteristic wavelength prediction model. The prediction accuracy of the models was evaluated according to the coefficient of determination R² and the relative analysis error RPD. The study found that the best prediction model for predicting phosphorus content in the pulp of 'Huangguan' pear was MSC-GA-PLSR, which had R²=0.843 and RPD=1.857 in the modelling set and R²=0.989 and RPD=7.041 in the prediction set. The best prediction model for predicting phosphorus content in the peel of ‘Huangguan’ pear was SG+SNV+FD-GA-PLSR, which had R²=0.991 and RPD=7.470 in the modelling set and R²=0.974 and RPD=4.414 in the prediction set, and the effect was good and met expectations. The results demonstrated that near-infrared spectroscopy could successfully achieve nondestructive detection of phosphorus content in the pulp and peel of 'Huangguan' pears.

To evaluate the nutrient load due to the grazing of laying hens in outdoor runs, soil characteristics were monitored in three Italian organic farms. For each farm, soil samples were taken from three increasing distances from the hen house and two depths and different chemical parameters were evaluated. The comparison among the results from the different distances shows that N-NO3 and Olsen P are the most affected parameters by hen faeces: both present high values with a statistically significant difference in the area close to the poultry house and for the most superficial layer. Even TKN and TOC show significant differences between the concentrations of the first layer (more concentrated) and those of the second layer (less concentrated). In general, the surface soil layer closest to the chicken house is the portion of the outdoor run most affected by chicken droppings and represents the most critical point in terms of potential environmental impact. Therefore, it is necessary to intensify the management of the outdoor run with tools that can facilitate the grazing of animals and with vegetation that can absorb nutrients by limiting leaching and run-off.

The Mediterranean region offers good weather conditions for outdoor pig production (OPP), which is considered more environmentally friendly than intensive indoor production. However, the continuous input of food and pigs' excreta increases the soil organic matter (SOM) and phosphorus (P), increasing the risk of waterbodies eutrophication. This work aimed at evaluating in OPP areas soil P dynamics and the role of SOM on P sorption and P release. The experiment was done for two years, at an area of 2.8 ha with an animal charge of 9 adults ha-1. Georeferenced soil samples were taken at 0.20 m depth, and a soil P sorption experiment was carried out. At the end of the experiment, for the background value, the levels of SOM increased between 85–376%, and Olsen P values ranged between -82–884%. SOM levels above 2% caused a decrease in the binding energy of P sorption according to the linear model b=-15.541SOM+115.20 (p <0.01) as well as a decrease of the soil P sorption capacity Qmax=-41.272SOM+298.37 (p <0.01). To avoid the accumulation of SOM and P preventing hotspots for waterbodies eutrophication, an adequate animal charge together with soil cultivation for pig grazing can be a cost-effective practice.

Tropical rainforests have the highest rates of net primary productivity (NPP) of the world. Hypotheses about the effect of edaphic nutrient contents, especially the availability of P, propose that they limit NPP of tropical forests or promote the redistribution of its above and belowground components. However, these hypotheses have not been tested experimentally in highly rainy tropical forests. To test such hypotheses, the effects of soil fertilization on the above and belowground NPP were evaluated in forests of two localities of Chocó (Colombia), one of the rainiest regions of the world. Five fertilization treatments (N, P, K, NPK and Control) were applied, and the above and belowground NPP were determined in permanent plots. There were no significant effects of treatments on total NPP; only the application of N significantly increased litter NPP. Additionally, a redistribution of the above and belowground NPP was found with the application of P, which increased the proportion of fine roots and litter, and decreased the woody components of forest NPP. This change of carbon allocation is interpreted as an ecophysiological mechanism to capture additional nutrients in soils with very low content of available P.

The inclusion of exogenous phytase in broiler P and Ca deficient diets in response to heightened concerns over excessive P excretion into the environment over the years has remarkably been documented. However, responses among these studies have been inconsistent because of the several factors affecting P utilization. For this reason, a systematic review with meta-analysis of results from forty-one studies published from 2000 to February 2024 was evaluated to: 1) quantitatively summarize the size of phytase effect on growth performance, bone strength, and mineralization in broilers fed P and Ca deficient basal diets and 2) estimate and explore the heterogeneity of the effect sizes of outcomes using sub-group and meta-regression analyses. The quality of the included studies was assessed using the Cochrane Collaboration’s SYRCLE Risk of Bias checklists for animal studies. Additionally, applying the random-effects models, Hedges’ g effect size of supplementation with phytase was calculated using the R software to determine the standardized mean difference (SMD) at a 95% confidence interval. Sub-group analysis and meta-regression further explored heterogeneity (P_SMD ≤ 0.05, I² > 50%, n ≥ 10). The meta-analysis showed that supplemental phytase increases ADFI and BWG and reduces FCR at each time point of growth (< 0.0001). Additionally, phytase supplementation consistently increased tibia ash, P and Ca, and bone strength (< 0.0001) of broilers fed P and Ca deficient diets. Results of the subgroup and meta-regression analyses showed that age and strain of broiler, dietary P source, and duration of phytase exposure significantly influence the effect size of phytase on growth and bone parameters. In conclusion, phytase can attenuate the effect of reducing dietary available phosphorus and calcium and improve ADFI, BWG, and reduced FCR, especially when added to starter diets. It further enhances bone ash, bone mineralization, and bone-breaking strength of broilers, even though the effects of bone ash and strength can be maximized in the starter phase of growth. However, the effect sizes of phytase were related to the age and strain of the broiler, dietary P source, and duration of phytase exposure rather than the dosage.

Abstract: Marine eutrophication is a pervasive and growing threat to global sustainability. Thereby nutrient discharges to the marine environment should be reduced to a minimum. When fertilizers are loaded to vessels in ports, a significant amount of nutrients are released into the sea, but so far these actions have received little attention. Here, we employed the Boosted Regression Trees modeling (BRT) to define relationships between fertilizer loading, loading area, rain intensity and nutrient discharge to the marine environment and then used the established relationships to predict daily nutrient discharge due to fertilizer loading. The studied subject was a port in the Gulf of Finland, where significant amount of both nitrogen and phosphorus are loaded to vessels. BRT models accounted for a significant proportion of the variability of nutrient discharge. As expected, the nutrient discharge increased with the amounts of fertilizers loaded and the intensity of rain. On the other hand, with increasing loading area the amounts of total nitrogen discharge increased, but phosphorus discharge decreased. The latter result may be due to different char-acteristics of the loading areas of different terminals. The model predicted that at the studied port the total nitrogen and phosphorus discharge into the marine environment due to fertilizer loading was 272,906 and 196 kg per year, respectively. Im-portantly, the developed model can be used to predict nutrient loads for different future scenarios to propose the best mitigation methods for nutrient discharges to the sea.

Phosphorus (P) deficiency is a major constraint limiting sustainable rice cultivation in sub-Saharan Africa—partly due to the deeply weathered soils that have low pH and contain high P-fixing Fe and Al oxides. Soil texture also affects P availability and use efficiency. In this study, we evaluated the combined effect of soil texture (sand, clay loam, and clay) and P treatments (P-dipping and two other P fertilizer levels) on growth of NERICA 4 rice in the initial growth stages. In a factorial experiment, we measured the interaction effects of soil texture and P treatments on shoot parameters and root morphology. Both treatments had significant interaction effects on all measured parameters, except shoot biomass, and affected the photosynthetic rate, with the highest mean values obtained under clay loam soil texture and P-dipping treatment, respectively. The treatments also affected rice root morphology. In a striking contrast, whereas mean root length under clay was significantly higher than that under clay loam texture, mean shoot P uptake under clay loam soil was significantly higher than that under clay soil texture. The interactive effect of soil texture and P-dipping influenced NERICA 4 shoot and root physiological and morphological characteristics under clay loam soil texture.

The influence of long-term chemical fertilization in paddy soils is based on the interaction between labile carbon and phosphorus fractions and how this influences soil organic carbon (SOC). Four soil depths (0–30 cm) were analyzed in this study. Easily oxidized organic carbon components, such as permanganate oxidized carbon (POXC) and dissolved organic carbon (DOC), and other physicochemical soil factors were evaluated. The correlation and principal component analyses were used to examine the relationship between soil depth and the parameter dataset. The results showed that Fe-P concentrations were greater in the 0–5 cm soil layer. DOC, inorganic phosphate fraction, and other soil physiochemical characteristics interacted more strongly with SOC in the 0–5 cm soil layer, compared to that in the 10–15 cm layer, influencing soil acidity. An increase in DOC in the 0–5 cm soil layer had a considerable effect on lowering SOC, consistent with P positively correlated with POXC, but negatively with SOC and water-soluble carbon (WSC). The changes in SOC could be attributed to the relationship between DOC and inorganic phosphate fractions (as Fe-P) under a specific soil pH condition. An increase in soil DOC could be caused by changes in the P fraction and pH. The DOC:Avai. P ratio could serve as a compromise for the C and P dynamic indicators. The soil depth interval is a critical element that influences these interactions. Agricultural policy and decision-making may be influenced by the P from chemical fertilization practices, considering the yields and environmental effects.

A field experiment was conducted on the farm of Abi Jarash in Agricultural Collage, different rates of olive solid waste and cow manure were used, as follows: (control, fresh olive solid waste 100%, fresh olive solid waste 75%+ cow manure 25%, fresh olive solid waste 50%+ cow manure 50%, fresh olive solid waste 25+ cow manure 75%, Fermented Olive Solid Waste 100%, Fermented olive solid waste 75%+ cow manure 25%, Fermented olive solid waste 50%+ cow manure 50%, Fermented olive solid waste 25+ cow manure 75%), wheat was seeded. The impact of fresh and fermented olive solid waste and cow manure on some chemical and fertility soil properties was studied. the olive solid waste treatment 100% which added had more effect on the organic matter, exchange capacity, nitrogen, phosphorus and potassium in soil, plant and productivity, after that the fermented olive solid waste 75% + cow manure, fresh olive solid waste 100% comparing with the control, the values of organic matter were (25% 2.73, 2.39) and the cation exchange capacity (21.76, 20.44, 19.38) and for phosphorus (303.3, 277.8, 171.8) mg / kg, while the values of potassium ​​were (303.3, 277.8, 171.8) mg / kg. In terms of plant content, the plant content of nitrogen, phosphorus and potassium were the same as for grains (2.784, 2.606, 2.126), (0.4535, 0.4226, 0.2753), (1.876, 1.762, 1.234) respectively, (0.2875, 0.2016) respectively for the same previous treatments and elements. olive solid waste 100% was the highest productivity comparing with the other treatments, where the productivity of wheat was (9.513) ton. ha-1.

Despite increased awareness of and attention to the need for sustainable agriculture, fertilizers and compost application in excess of crop requirements remain common agricultural practices in South Korea, causing eutrophication of freshwater and coastal ecosystems. In this study, a phosphorus (P) budget was developed to quantify P inputs, outputs, and retention in a forested- agricultural watershed. The P budget showed that chemical fertilizers and organic compost were the largest source of P (97.6% of the total) followed by atmospheric deposition (2.1% of the total P), whereas forest export (0.2% of the total) and sewage treatment plants (STPs) (0.1% of the total) were negligible. The dominant P outputs were crop harvesting and hydrologic export to surface water. The P balance showed a significant accumulation of P in the watershed; approximately 87% of the total P input was retained in the soils within the watershed. However, P concentrations in drainage water were still high enough to cause eutrophication of downstream reservoirs. The results provide useful information on the proportion of P export and retention in soils and will help support efforts to improve water quality and design better management of agricultural non-point source pollution.

Incidental P losses from non-point sources may contribute to eutrophication and to decreased soil fertility. These incidents have been related to heavy rainfall on freshly fertilized agricultural soils and little is known about such incidents on more natural soils or in forests. The aim of this work is to determine if incidents of high P leaching also occur in spruce forests, and if such incidents are of significance in P cycling. We found a peak in the mineral soil solution showing that single events of high P leaching occur. The orthophosphate concentration in the Bf-horizon of the 80-year old spruce forest peaked in the autumn of the second year of a continuous monitoring. The concentration increased by more than 85 times compared to the highest concentration obtained earlier during the sampling. The amount leached during this 6 months peak is 10 times higher than the average annual leaching. This P leaching might be due to a combination of high P deposition/through-fall and a high anion exchange with dissolved-organic-carbon and Cl-. We suggest that single events of high sub-surface P leaching may contribute to the overall P leaching, and might increase with the global warming as more DOC is expected to be released to the soil solution.

Phosphate (Pi) deficiency reduces nodule formation and development in different legume species including common bean. Despite the significant progress in the understanding of the genetic responses underlying the adaptation of nodules to Pi deficiency, it is still unclear whether this nutritional deficiency interferes with the molecular dialog between legumes and rhizobia, if so, what part of the molecular dialog is impaired? In this study, we provide evidence demonstrating that Pi deficiency negatively affects critical early molecular and physiological responses required for a successful symbiosis between common bean and rhizobia. We demonstrated that the infection thread formation and the expression of PvNSP2, PvNIN, and PvFLOT2, genes controlling the nodulation process, were significantly reduced in Pi-deficient common bean seedlings. Further transcriptional analysis revealed that the expression of hormones-related genes is compromised in Pi-deficient seedlings inoculated with rhizobia. Additionally, we showed that regardless of the presence or absence of rhizobia, the expression of PvRIC1 and PvRIC2, two genes participating in the autoregulation of nodule number, was higher in Pi-deficient seedlings than in control seedlings. The data presented in this study shed light on the understanding of how Pi deficiency impacts the early steps of the symbiosis between common bean and rhizobia.

Phosphorus is required by laying hens for a variety of biological functions. It is usually provided in excess, in a readily digestible inorganic form in diet formulations. However, this does not represent an efficient use of a finite resource and can result in water pollution. Plant bound phosphorus in phytate, is common in commercial poultry diets, and represents an alternate source of phosphorus, however poultry lacks the enzyme to digest it. By adding enzymes to their diets, the availability of this phytate-bound phosphorus can be increased allowing for the reduced inclusion of inorganic P in the diet formulation. Therefore, this study was conducted to examine the effect of a natural enzyme complex that contains phytase and xylanase in layer diets. Novogen Brown Classic layers (n=314) were fed one of two diets: (T1) control diet or (T2) control diet plus a natural mixed-enzyme product with both, phytase and xylanase. Experimental diets were provided for 12 days after which the excreta from each pen were collected for an additional three days to determine total retention and ileal digestibility of phosphorus and gross energy. At the end of the trial the birds were euthanized, and their ileal contents were collected. Productivity parameters were also recorded over the course of the study. The amount of phosphorus detected in the excreta of the control group was significantly higher than the amount detected in the enzyme-supplemented group (P<0.05). Both phosphorus retention and phosphorus ileal digestibility were significantly higher in the enzyme-supplemented birds (P<0.001). Gross energy digestibility was significantly higher in the enzyme-supplemented birds for both the total tract and ileal samples (P<0.001). There were only numerical improvements, not significant, in the layer productivity parameters. This study showed that the enzyme supplement can improve total retention and ileal digestibility of phosphorus and gross energy in older layers.

Dredging is a common technique for managing eutrophication problems in waters, reducing the accumulation of pollutants by removing sediments from the bottom of water bodies. However, dredging can cause complex impacts on lake ecosystems, and it is crucial to understand benefits and mechanisms for environments. In this paper, the dredged and undredged areas in the Caohai portion of Dianchi Lake were studied to analyze the effects of dredging on nitrogen-phosphorus transport and conversion and changes in nitrogen-phosphorus morphology content and its mechanisms by comparing the nitrogen-phosphorus morphology content, percentage; nitro-gen-phosphorus ratio, and release contribution of the two areas. It was found that the ratio of sta-bilized nitrogen (SN) to stabilized phosphorus (SP) in the dredged area was lower than that in the non-dredged area; the BD-P and TOC contents had a large turnaround at the 16-20 cm position of the sediment in the dredged area; and the main conclusions were that the dredging would disrupt the internal equilibrium of the lake system for many years, and in particular, it would have the greatest effect on the balance of the BD-P in the phosphorus forms of the sediment, and that the column cores of the dredged area from 0 to 16 cm might be newly accumulated sediments after the dredging project. However, with time, the distribution of nitrogen and phosphorus forms in the newly accumulated sediments will gradually reach a new equilibrium. In addition, dredging will also cause significant changes in the retention efficiency of nitrogen and phosphorus in the sediment, and the stable nitrogen and phosphorus forms will be released and transformed into unstable ni-trogen and phosphorus forms.

The effect of organic matter (OM) on soil P-sorption is controversial and needs to be more investigated. The dissolved organic matter (DOM) may be regarded as an influential component on P sorption in natural soils. However, despite the great need for renewable sources of available P and OM in agricultural soils, little is known about interaction between P and DOM in natural soil systems. To uncover if and how soil saturation with DOM derived from different types of abundant agricultural wastes (cattle manure, horse manure, biogas digestate, compost) affects the phosphate sorption, we examined P sorption process in control and DOM-saturated sandy soils. The results indicated that organic matter introduced with agricultural wastes did not always reduce P sorption, but certainly had an effect on impairing P fixation and thus may result in potentially greater P mobility in the soil, including P availability. Up to now, we cannot recommend any of the tested organic amendments to directly overcome the P fixation in arable soils.

A series of dinuclear copper(I) N,C,N- and P,C,P-carbodiphosphorane (CDP) complexes using multidentate ligands CDP(Py)2 (1) and (CDP(CH2PPh2)2 (13) have been isolated and characterized. Detailed structural information was gained by single crystal XRD analyses of nine representative examples. The common structural motive is the central double ylidic carbon atom with its characteristic two lone-pairs involved into binding of two geminal L-Cu(I) fragments at Cu-Cu distances in the range 2.55 – 2.67 Å. In order to enhance conformational rigidity within the characteristic Cu-C-Cu triangle, two types of chelating side arms were symmetrically attached to each phosphorus atom: two 2-pyridyl functions in ligand CDP(Py)2 (1) and its dinuclear copper complexes 2-9 and 11, as well as two diphenylphosphinomethylene functions in ligand CDP(CH2PPh2)2 (13) and its di- and mononuclear complexes 14-18. Neutral complexes were typically obtained via reaction of 1 with Cu(I) species CuCl, CuI, and CuSPh or via salt elimination reaction of [(CuCl)2(CDP(Py)2] (2) with sodium carbazolate. Cationic Cu(I) complexes were prepared upon treating 1 with two equivalents of [Cu(NCMe)4]PF6, followed by the addition of either two equivalent of an aryl phosphine (PPh3, P(C6H4OMe)3) or one equivalent of a bisphosphine ligands DPEPhos, XantPhos or dppf. For the first time carbodiphosphorane CDP(CH2PPh2)2 (13) could be isolated upon treating its precursor [CH(dppm)2]Cl (12) with NaNH2 in liquid NH3. A protonated and a deprotonated derivative of ligand 13 were prepared and their coordination was compared to neutral CDP ligand 13. NMR analysis and DFT calculations reveal, that the most stable tautomer of 13 does not show a CDP (or carbone) structure in its uncoordinated base form. For most of the prepared complexes, photoluminescence upon irradiation with UV light at room temperature was observed. Quantum yields (PL) were determined to 36% for dicationic [(CuPPh3)2(CDP(Py)2)](PF6)2 (4) and to 60% for neutral [(CuSPh)2(CDP(CH2PPh2)2] (16).

Although corn is the most important and nitrogen (N)-fertilized crop, there is a lack of long-term data on the effects of organic and inorganic N fertilizer on N balance and losses for corn systems under different tillage systems. From 2012 to 2023 we assessed the effects of N sources on grain yields from cultivated continuous corn receiving irrigation at a site with minimal erosion in Fort Collins, Colorado, USA, and compared these effects to no-till (NT) and strip till (ST) systems receiving inorganic N. An N balance accounting for N and carbon (C) sequestration found a system nitrogen use efficiency (NUE_Sys) for organic N fertilizer (manure) with tillage of 86.3%, which was higher than the NUE_Sys of 60.2% with inorganic N fertilizer (enhanced efficiency fertilizer, EEF). Conventional tillage with manure use is a good management practice that contributed to higher grain yields (2 of 11 yr.), C sequestration (P<0.05), soil organic N content (P<0.05), and soil phosphorus (P) content than inorganic N fertilizer with tillage (P<0.05). Tilled systems, whether receiving organic or inorganic N fertilizer, had higher yields and grain N content than NT and ST systems receiving inorganic N fertilizer (P<0.05). The grain production of the cultivated system receiving organic N fertilizer did not decrease with time, while the yields of the cultivated system receiving inorganic N fertilizer decreased with time (P<0.05), suggesting that cultivated systems receiving organic N fertilizer may be more sustainable and better able to adapt to a changing climate. Additionally, a combination of manure (30% of N input) with EEF (70% of N input) contributed to a synergistic effect that increased agronomic productivity (harvested grain yields).

The major issue of raw materials depletion and more specifically of phosphorous (an important fertilizer) has currently become an emergent aspect, due to expected depletion problems, needing immediate handling. This was the reason for the implementation of PhoReSe project that aimed to remove and recover phosphorus from the secondary (biologically treated) effluent of a municipal wastewater treatment plant (WWTP “AINEIA”, located near Thessaloniki, N. Greece), treating the wastewaters of the nearby touristic area. Regarding the phosphorous supplementary removal and recovery treatment options, two methods mainly examined, initially in laboratory scale (batch experiments), i.e. (1) the adsorption of phosphorous, and (2) the chemical precipitation of phosphorus. Both methods further applied in pilot-scale, by performing initially the adsorption of phosphorous onto the AquAsZero commercial sorbent, which is a mixed manganese iron oxy-hydroxide, followed by the chemical precipitation of phosphorous, implemented after the de-sorption process of previously saturated adsorbent. The final precipitate of this procedure examined as an alternative/supplementary fertilizer, returning with this way phosphorus into the natural cycle. These experiments, as applied successfully in pilot-scale, set the basis for the larger-scale relevant application for similar WWTP facilities.

Phosphorus, an essential rare element in aquatic ecosystems, plays a key role in maintaining ecosystem balance. However, an excess of phosphorus will lead to eutrophication and algal pro-liferation. To prevent eutrophication, it is crucial to pretreat and measure the concentration of total phosphorus (TP). Compared with conventional TP pretreatment equipment (autoclave), a lab-on-a-chip detection device fabricated through micro-electromechanical system technology using titania (TiO2) as a photocatalyst is more convenient, efficient, and cost-effective. However, the wide bandgap of TiO2 (3.2 eV) limits the photocatalytic activity. To address this problem, this paper describes the preparation of a TiO2/Au nanocomposite film by electron-beam evaporation and atomic layer deposition, based on the introduction of a gold film and TiO2 on a quartz substrate. The photocatalytic degradation properties of TiO2/Au nanocomposite films with thicknesses of 1, 2, 3, and 4 nm are assessed using rhodamine B as a pollutant. Experimental results demonstrate that the deposition of a gold film with different thicknesses can enhance the photocatalytic degradation efficiency through synergetic reactions in the charge separation process on the surface. The optimal photocatalytic efficiency is achieved when the deposition thickness is 2 nm, and it decreases with further increase in the thickness. When the photocatalytic reaction time is 15 min, the LOC device with a 2-nm-thick gold layer and autoclave exhibit similar TP pretreatment performance. Therefore, the proposed LOC device based on photocatalysis technology can address the limitation of conventional autoclave equipment, such as large volume, long processing time, and high cost, thereby satisfying the growing demand for on-site evaluation.

In the Northeast of Portugal, like in many parts of the world, most soils are acidic, which may hamper crop productivity. This study presents the findings of a factorial experiment involving three factors: i) soil type [schist (Sch) and granite (Gra)]; ii) cultivars [Cobrançosa (Cob) and Arbequina (Arb)]; and iii) fertilizer treatments [liming (CaCO3) plus Mg (LMg), P application (+P), B application (+B), all fertilizing materials combined (Con+), and an untreated control (Con-)]. Dry matter yield (DMY) did not show significant differences between cultivars, but plants grown in schist soil exhibited significantly higher biomass compared to those in granite soil. Among the treatments, +B and Con+ resulted in the highest DMY (50.8 and 47.2 g pot-1, respectively), followed by +P (34.3 g pot-1) and Con- (28.6 g pot-1). Treatment LMg yielded significantly lower values (15.6 g pot-1) than Con-. LMg raised the pH above 7 (7.36), leading to a severe B deficiency. Although Con+ also raised the pH above 7 (7.48), it ranked among the most productive treatments for providing B. Therefore, when applying lime to B-poor sandy soils, moderate rates are advised to avoid inducing a B deficiency. Additionally, it seems prudent to apply B after lime application.

Dissolved organic matter (DOM) derived from organic fertilizers may increase soil phosphorus (P) availability. However, the frequently observed correlation between soil P availability and dissolved organic carbon (DOC) content has led to an excessive focus on DOC content at the expense of DOM properties. The present study investigated the influence of DOM characteristics on soil P availability by using a 6-year field experiment and microcosms of P sorption in paddy soil. Our results showed that partial replacement of chemical P fertilizer with manure or crop straw increased P fertilizer-use efficiency, even when decreasing chemical P input by 34 %, compared to normal chemical fertilization. The microcosm experiment demonstrated that DOM properties, rather than total DOC content, determine soil P sorption capacity, despite the significant correlation between DOC content and P availability observed in the field experiment. Manure-DOM exerted stronger inhibitory effects on P sorption than straw-DOM, and high molecular weight (HMW)-fractionated DOM exerted stronger inhibitory effects on P sorption than low-molecular-weight-fractionated DOM by 16-20%. The mechanism was rooted in the HMW DOM with unique characteristics (e.g., strong aromaticity, hydrophobicity, abundant humic-like components, carboxyl groups, and benzene ring structures) competing for soil P sorption sites (e.g., reduction in specific surface area and micropore volume), decreasing the soil surface charge (e.g., zeta potential), and thereby suppressing P sorption in paddy soil. Our study points out a promising avenue for regulating organic matter properties with organic fertilization to improve P use efficiency in agricultural soils.

The few studies dealing with leaf phenological responses to elevated nutrients in forest trees have given ambiguous results, i.e., while some reported delayed leaf-out and autumn leaf senescence, others reported advanced leaf phenology caused by increased nutrition. This study aimed to determine the effects of experimentally increased phosphorus (+P) on the leaf phenologies of two juvenile provenances of common beech and sessile oak. Other objectives were to determine whether there are interspecies differences as well as intraspecies variations. Saplings were excavated in two mixed beech-oak stands and transplanted into four wooden boxes filled with a commercial soil substrate. Phosphorus fertilizer was added to two of the boxes, while the remaining boxes served as controls. Both species responded to +P treatment with advanced autumn leaf senescence in the first year of the experiment. Leaf senescence in common beech began significantly earlier, while in both species, the process was accelerated compared to that in the control. In the second year, the leaf senescence response to +P treatment was even more pronounced in both species. The +P effect on leafing phenology was absent in both common beech provenances and in an oak provenance. However, the other oak provenance showed advanced leafing, indicating the existence of intraspecies differences.

Phosphorus (P) is the most important substance in inorganic fertilizers used in agriculture industry. In this study, a multi-product and multi-objective model is presented considering economic and environmental concerns to design a renewable and sustainable P-fertilizer supply chain management (PFSCM). To handle complexities of the proposed model, an ensemble knowledge-based three-stage heuristic-metaheuristic algorithm utilizing heuristic information available in the model, whale optimization algorithm, and variable neighborhood search (named H-WOA-VNS) is proposed. At first, a problem-dependent heuristic is designed to generate a set of near-optimal feasible solutions. These solutions are fed into a population-based whale optimization algorithm which benefits from both exploration and exploitation strategies. Finally, a single-solution metaheuristic based on variable neighborhood search is applied to further improve the quality of the solution using local search operators. The objective function of the algorithm is formulated as a weighted average function to minimize total economic cost, while increasing crop yield and P use efficiency. Experimental results over five synthetic datasets and a real case study of the P-fertilizer supply chain confirm the superiority of the proposed method against the state-of-the-art techniques. The results demonstrate that the proposed method performs well in optimizing both the economic cost and environmental issues.

Urban stormwater runoff from a medium-density residential development in southeast Queensland has been monitored in the field since November 2013. A treatment train installed on the site includes rainwater tanks collecting roofwater, 200-micron mesh baskets installed in grated gully pits and two 850 mm high media filtration cartridges installed in an underground 4 m³ vault. A monitoring protocol developed by research partners, Queensland University of Technology (QUT), guided the monitoring process over a 4.5-year period. Heavy metals were included in the list of analytes during the monitoring period as the catchment is within 1 km of the environmentally-sensitive Moreton Bay, Queensland. Removal efficiencies observed at this site for the regulated pollutants; total suspended solids (TSS), total phosphorus (TP) and total nitrogen (TN) for the pit baskets were 61%, 28% and 45% respectively. The cartridge filters removed 78% TSS, 59% TP, 42% TN, 40% total copper and 51% total zinc. As the measured influent concentrations to the cartridge filters were low when compared to industry guidelines, the dataset was merged with international field results for TSS (n=39) and TP (n=32) but truncated within anticipated guideline levels. The combined dataset for the media filter demonstrates performance at 89% TSS, 66% TP and 42% TN. The total gross pollutant generation rate from the medium-density residential catchment was observed to be 0.24 m³/Ha/year, with a corresponding air-dried mass of 142.5 kg/Ha/year. Less than 2% of the gross pollutant mass was anthropogenic. The findings of this research suggest that the treatment train, and in particular the media filter, holds promise for the removal of total copper and total zinc, in addition to TSS, TP and TN, from urban stormwater runoff. Based on a maximum, low risk trigger TN concentration of 1.5 mg/L, the field test data from 4.5 years of operation and standard maintenance, suggests a 5.5-year replacement interval for the media filters.

In the study of QSAR/QSPR, due to high degree of predictability of pharmaceutical properties, the eccentric-connectivity index has very important place among the other topological descriptors, In this paper, we compute the exact formulas of eccentric-connectivity index and its corresponding polynomial, total eccentric-connectivity index and its corresponding polynomial, first Zagreb eccentricity index, augmented eccentric-connectivity index, modified eccentric-connectivity index and its corresponding polynomial for a class of phosphorus containing dendrimers.

Pressmud, a by-product of sugarcane processing, is typically disposed of through incineration or landfilling, though it has considerable potential in organic agriculture. This study explored the com-posting of pressmud through bioaugmentation using specific bacterial strains. Two experimental setups were created: E2 with a cellulolytic and phosphorus-solubilizing strain, Bacillus amyloliquefa-ciens-ASK11, and E3 with a nitrogen-fixing strain, Bacillus megaterium-ASNF3. A control setup (E5) was also maintained without bacterial augmentation. Nitrogen (N) and phosphorus (P) contents were measured using the Kjeldahl and Olsen methods, respectively, while Fourier-Transform Infra-red (FTIR) spectroscopy confirmed compost maturity. Results indicated that the Bacillus-enhanced composts in E2 and E3 significantly increased the nitrogen(49.27% and 91.23%) and phosphorus contents(129% and 83.85%), respectively, compared to the control with only 13.62% N and 65% P contents after 60 days of the pressmud compost maturity.. Additionally, organic matter decomposi-tion improved by 49-50% in the bioaugmented setups after 60 days. FTIR analysis revealed organic phosphate peaks and P-O-C stretching bands at 1025 cm-1 in the E2 compost, while a nitrogen vi-bration band at 3849 cm-1 in E3 indicated significantly higher nitrogen content compared to the control. The Bacillus-enriched pressmud compost not only accelerated the composting process but also enhanced nutrient levels, positioning it as a promising biofertilizer for rehabilitating barren lands.

New antibiotics are unquestionably needed in the fight to the emergence and spread of multidrug-resistant bacteria. So far, antibiotics targeting bacterial central metabolism have been poorly investigated. By determining the minimal inhibitory concentration (MIC) of desmethylphosphinothricin (Glu-γ-PH), an analogue of glutamate with a phosphinic moiety re-placing the γ-carboxyl group, we previously showed its promising antibacterial activity on Escherichia coli. Herein we synthetized and determined the growth inhibition exerted on E. coli by an L-Leu dipeptide derivative of Glu-γ-PH (L-Leu-D,L-Glu-γ-PH). Furthermore, we compared the growth inhibition obtained with this dipeptide with that exerted by the free amino acid, i.e. Glu-γ-PH, and by their phosphonic and non-desmethylated analogues. All tested compounds were more effective when assayed in chemically defined minimal medium. The dipeptide L-Leu-D,L-Glu-γ-PH had a significantly improved antibacterial activity (2 μg/mL), at a concentra-tion between the non-desmethytaled (0.1 μg/mL) and the phosphonic (80 μg/mL) analogues. Also in Bacillus subtilis the dipeptide L-Leu-D,L-Glu-γ-PH displayed an activity comparable to that of the antibiotic amoxicillin. This work highlights the antibacterial relevance of the phosphinic pharmacophore and proposes new avenues to the development of novel antimicrobial drugs containing the phosphinic moiety.

Soil is an extremely significant resource for human survival, and agglomerates, as the basic unit of soil structure, not only enhance soil fertility and control the biological validity of nutrients, but also strengthen the soil's erosion resistance. The mass application of fertilizers may have a significant impact on crop growth and soil structure, and the rational application and dispensing of fertilizers will be an urgent issue to be addressed. Therefore, the effect of fertilizer application on the stability of water-stable soil aggregates needs to be studied under different meteorological and soil conditions to draw more general and feasible conclusions. Our Meta-analysis of data from 220 of 56 published studies found that fertilizer application increased mean weight diameter (MWD) by an average of 18% compared to the no-fertilizer treatment. Among the nitrogen (N), phosphate (P), and organic (OM) fertilizer treatments, the organic fertilizer treatment had a greater stimulatory effect on MWD (26%). Among the different fertilizer levels, low level of phosphorus (<40kg·hm-2·yr-1), high level of N (>120kg·hm-2·yr-1), and low level of organic fertilizer (<5000kg·hm-2·yr-1) increased MWD by 19%, 14%, and 41% respectively. Across soil types and land use types, the response to MWD was positive for red soils and paddy fields, and the stimulatory effect of organic fertilizer was more significant compared to chemical fertilizer. The regression model showed that the response ratio of MWD was negatively correlated with the response ratio of soil pH and bulk density (BD), and positively correlated with the response ratio of soil organic carbon (SOC) and microbial mass carbon (MBC). Meanwhile, the PLS-SEM model showed that average annual temperature was the main factor affecting the stability of soil aggregates, and the average annual rainfall is the secondary factor. Therefore, this study found that the long-term use of organic fertilizers in place of some chemical fertilizers was more effective than chemical fertilizer alone. Temperature and rainfall have greater effects on the response of fertilizer to soil aggregate stability.

Nutrient recovery technologies have been constantly developed and optimised to address challenges in water and wastewater management, sanitation, and agri-food systems, while promoting sustainable management of resources, and circular phosphorus economy. However, these technologies have been rarely explored beyond laboratory-scale in developing countries where it is mostly needed, such as the Philippines. In this study, a nutrient recovery batch reactor system was installed at a local farm to process raw septage from an onsite sanitation system, septic tank, to recover a high-value fertiliser for local crop production. The batch reactor was used for two processes; acid hydrolysis for pre-treatment of septage and chemical precipitation to recover phosphorus fertiliser (RPF). The recovered fertiliser was then applied to produce eggplants and tomatoes, which are the common crops grown in the farm. Results show that an average of 290 g of recovered RPF was produced for every 100 L of raw septage processed. With hydrolysis, 77% of the phosphate concentration were released as phosphates from the solid component of the raw septage. About 98.5% of phosphates were recovered from the hydrolysed septage. The RPF when applied to the farm’s eggplants and tomatoes have yields comparable to that of the commercial fertilisers. This study was able to demonstrate the potential of a resource-oriented sanitation system that promotes nutrient recycling toward sustainable agriculture that further leads to meeting the United Nation’s Sustainable Development Goals, particularly Zero Hunger (goal 2), Clean Water and Sanitation (goal 6), Sustainable Cities and Communities (goal 11), and Responsible Consumption and Production (goal 12).

Plants do need a fixed proportion of carbon (C), nitrogen (N) and phosphorus (P) elements to maintain normal metabolic activities. The P fertilizers are widely used to supplement nutrients in subtropical plantations. Stoichiometric homeostasis reflects the strategy of plants to cope with various environments (including P fertilizer supply rate). It is thus of great significance to understand C:N:P stoichiometry in the plant-litter-soil system under P addition and stoichiometric homeostasis of plant tissues for fertilization management of slash pine (Pinus elliottii Engelm) plantations. We measured the C, N and P contents in root, branch, needle, litter and soil in slash pine plantations fertilized with four treatments - P1 (25 kg P ha−1 yr−1), P2 (50 kg P ha−1 yr−1), P3 (100 kg P ha−1 yr−1), and a control (CK) in subtropical China and calculated stoichiometric homeostasis of plant tissues. Results showed that P addition increased the capacity of needle to obtain C, N and P elements and altered the C:N:P stoichiometry of plant tissues, as well promoted the accumulation of C and P elements in soil, but had no significant effect on soil stoichiometry. The nutrient contents of needle and branch were higher than those of root and litter, indicating that slash pine was more inclined to allocate nutrient to the aboveground tissues. The stoichiometric homeostasis of C, N and P among plant tissues was ranked as follows: root > branch > needle, and homeostasis of nutrient elements in the needle was C > N > P. This indicated that the C, N and P stoichiometric homeostasis was various among plant tissues and elements types under P addition. These findings suggest P addition would alleviate the P limitation of slash pine growth in subtropical regions. In the future, long-term observation experiments should be conducted and the trade-off between P addition rates and economic and ecological benefits should be considered.

Following legalization, cannabis has quickly become an important horticultural crop in Canada and increasingly so in other parts of the world. However, due to previous legal restrictions on cannabis research there are limited scientific data on the relationship between nitrogen (N), phosphorus (P), and potassium (K) supply (collectively: NPK) and the crop yield and quality. This study examined the response of a high delta-9-tetrahydrocannabinol (THC) Cannabis sativa cultivar grown in deep-water culture with different nutrient solution treatments varying in their concentrations (mg L^-1) of N (70, 120, 180, 250, 290), P (20, 40, 60, 80, 100) and K (60, 120, 200, 280, 340) according to a central composite design. Results demonstrated that inflorescence yield responded quadratically to N and P, with the optimal concentrations predicted to be 194 and 59 mg L^-1, respectively. Inflorescence yield did not respond to K in the tested range. These results can provide guidance to cultivators when formulating nutrient solutions for soilless cannabis production and demonstrates the utility of surface response design for efficient multi-nutrient optimization.

To develop green super rice varieties with high and stable yields under the rainfed conditions and improved nutrient use efficiency (NuUE), a modified backcross (BC) breeding approach was adopted using a high yielding and widely adaptable Xian variety, WTR1, as the recipient and a Geng variety, HAN, as the donor. Starting from the BC1F2 generation, the BC population had gone through one generation of selection under the IG, LI and RF conditions, followed by consecutive four generations of screening and selection for high GY under six different nutrient conditions, leading to the development of 230 BC1F6 introgression lines (ILs). The final evaluation of the 230 ILs under the six nutrient conditions identified many ILs with improved yields under various combinations of nutrient deficient conditions, including 12 promising lines that had significantly improved NuUE under two or more nutrient deficiency conditions. Our results demonstrated an efficient inter-subspecific BC breeding procedure with first round selection under the rainfed-drought condition followed by four generations of progeny testing for yield performances under six different nutrient conditions. The promising ILs were studied under replicated yield trials under 75N and -NPK conditions for developing high yield rice varieties with improved NuUE. Our results indicated that NuUE in rice was controlled by complex genetic and physiological mechanisms and the developed ILs provided useful materials for genetic and molecular dissection of NuUE in rice.

The negative impact of drought on plant growth may be modified by different availability of mineral nutrients and by their adaptation to different local habitat conditions. In this study, we examine the impact of drought, fertilization with phosphorus and provenance, as well as their interactions, on the growth and allometric growth relationships between belowground and aboveground organs of common beech (Fagus sylvatica) and sessile oak (Quercus petraea). The research was conducted on saplings originating from two mature mixed stands (dry and wet provenances) dominated by these species. In the common garden experiment, saplings were exposed to regular watering and drought in interaction with moderate and high phosphorus concentrations in the growing substrate (achieved by phosphorus fertilization). Obtained results indicate negative impact of drought and phosphorus fertilization on the growth of both species. In common beech, phosphorus fertilization had a negative impact on its adaptive capacity to drought, because of the unfavourable ratios between fine root mass and mass of other organs. The sessile oak provenances under the impact of drought showed a different root collar diameter/stem height increment ratio, which indicates its different phenotypic plasticity as a consequence of adaptation to different frequencies of dry periods in their natural habitats.

Intercropping of maize (Zea mays L.) and peanuts (Arachis hypogaea L.) (M||P) significantly enhances crop yield. In a long-term M||P field experiment with two P fertilizer levels, we examined how long-term M||P affects topsoil aggregate fractions and stability, organic carbon (SOC), available phosphorus (AP), and total phosphorus (TP) in each aggregate fraction, along with crop yields. Compared to their respective monocultures, long-term M||P substantially increased the proportion of topsoil mechanical macroaggregates (7.6–16.3%) and water-stable macroaggregates (>1 mm) (13.8–36.1%), while reducing the unstable aggregate index (ELT) and the percentage of aggregation destruction (PAD). M||P significantly boosted the concentration (12.9–39.9%) and contribution rate (4.1–47.9%) of SOC in macroaggregates compared to single crops. Moreover, the concentration of TP in macroaggregates (>1 mm) and AP in each aggregate fraction of M||P exceeded that of the respective single crops (P<0.05). Furthermore, M||P significantly increased the Ca2-P, Ca8-P, Al-P, and Fe-P concentrations of intercropped maize (IM) and the Ca8-P, O-P, and Ca10-P concentrations of intercropped peanuts (IP). The land equivalent ratio (LER) of M||P was higher than one, and M||P stubble improved the yield of subsequent winter wheat (Triticum aestivum L.) compared with sole-crop maize stubble. P application augmented the concentration of SOC, TP, and AP in macroaggregates, resulting in improved crop yields. In conclusion, our findings suggest that long-term M||P combined with P application, sustains farmland productivity in the North China Plain by increasing SOC and macroaggregate fractions, improving aggregate stability, and enhancing soil P availability.

The influence of the Fe2O3 addition amount on the dephosphorization of hot metal at 1623 K with the slag of the low basicity (CaO/SiO2) of about 1.5 was investigated by using high-temperature laboratorial experiments. With increasing the Fe2O3 addition amount, the contents of [C], [Si], [Mn] and [P] in hot metal at the end of dephosphorization decrease, and the corresponding removal ratios increase. The P2O5 content in slag increases, and the CaO and SiO2 contents in slag decrease. The phosphorus mainly exists in the form of the nCa2SiO4-Ca3(PO4)2 solid solution in the phosphorus-rich phase and the value of coefficient n decreases from 20 to 1 with increasing the Fe2O3 addition amount from 5 g to 30 g. With increasing the Fe2O3 addition amount, the oxygen potential and activity at the interface between the slag and hot metal increase. When the oxygen potential and the oxygen activity at the interface are greater than 0.72×10-12 and 7.1×10-3, respectively, the dephosphorization ratio begins to increase rapidly. With increasing the Fe2O3 addition amount to 30 g, the ratio of the Fe2O3 addition amount to theoretical calculation consumption is around 175%, and the dephosphorization ratio reaches the highest value of 83.3%.

This study investigated the speciation, transformation and availability of P during indigenous vegetable production by employing a combination of chemical and spectroscopic techniques. The study focused upon sites in two ecozones of SSA, the Dry Savanna (lna, Benin Republic) and Rainforest (Ilesha, Nigeria). Both sites were cultivated with two indigenous vegetable species; local amaranth (Amaranthus cruentus (AV)) and African eggplant (Solanum macrocarpon (SM)). The soils were treated with 5 t/ha poultry manure and urea fertilizer at the rate of 0, 20, 40, 60 and 80 kg N/ha. Soil samples were collected before planting and after harvest. Phosphorus K-edge X-ray absorption near-edge structure (XANES) spectroscopy was used to determine P speciation in these soils. Quantitative analysis showed that adsorbed and organic P were the two dominant P species in the manure amended Dry Savanna (DS) soils before planting and after harvest in soils cultivated with both AV and SM, with the addition of urea (40 kg N/ha) causing an increase in the organic P form in Dry Savanna soils cultivated with AV. Soils of the Rainforest (RF) cultivated with AV initially had large amounts of apatite P in the manure amended soils prior to planting which was transformed to adsorbed and organic P after harvest. Urea addition to the Rainforest soils shifted the dominant P species from organic P to adsorbed and apatite P, which is likely to limit P availability. Soils cultivated with SM had similar proportions of both organic and adsorbed P forms, with 40 kg N/ha addition slightly increased the proportion of adsorbed P.

Disrupted nutrient recycling is a significant problem for Europe, while phosphorus and nitrogen are wasted instead of being used for plant nutrition. Mineral phosphate is critical raw material, which contains environmentally hazardous elements such as cadmium and uranium. Therefore, phosphorus recovery from agricultural by-product streams is critically important key priority. Phosphorus recovery from food grade animal bone by-products have been applied researched since 2002 with objective driven evolution progress towards specialized pyrolysis processing technology and animal bone char product (ABC) developments in economical industrial scale. Different animal bone by-products tested under different conditions at 400 kg/h throughput capacity in the continuously operated 3R zero emission autothermal carbonization system. The different material core treatment temperatures (between >300°C and <850°C) were combined with different residence times under industrial productive processing conditions. It has been industrial demonstrated that material core treatment temperature <850°C with 20 minutes residence time is necessary to achieve high quality ABC with useful agronomic value. The output ABC product having concentrated >30% phosphorus pentoxide (P2O5) and specific quality innovative fertilizer for agronomical efficient organic and low input farming applications as functional organic fertilizer, soil improver, growing medium and/or fertilizing product blend with high mineral phosphate fertiliser replacement value.

In this study, a decentralized incineration facility was evaluated over a three-year period, focusing on performance aspects such as burning rate, ash production, fuel and electricity consumption, and ash composition while processing animal by-products (ABP). The total cost for ABP incineration was determined to be 159 € per ton of ABP, with the major components being capital depreciation (42%), maintenance expenditures (26%), labor (18%), and transportation costs (9%). Liquified petroleum gas (LPG) consumption ranged from 3-7 kg per ton of ABP, while electricity use was between 15-20 kWh per ton of ABP incinerated. The incineration process generated 7-10% (by weight) ABP ash, which was characterized by high calcium and phosphorus content and low levels of hazardous trace elements. Leaching tests demonstrated the potential for recovering the alkaline supernatant for flue gas treatment and the phosphorus-rich slurry for fertilizer production. The findings suggest that energy recovery and valorization are crucial for minimizing operational costs and environmental impact, emphasizing the benefits of integrating advanced resource recovery techniques in ABP incineration facilities.

The integration of Wireless Sensor Networks (WSNs) into agricultural areas has had a significant impact and has provided new, more complex, efficient, and structured solutions for enhancing crop production. This research reviews the role of Wireless Sensor Networks (WSNs) in monitoring the macro-nutrient content of plants. The review study focuses on identifying the types of sensors used to measure macro-nutrients, determining sensor placement within agricultural areas, implementing wireless technology for sensor communication, and selecting device transmission intervals and ratings. The study of NPK (Nitrogen, Phosphorus, Potassium) monitoring using sensor technology in precision agriculture is of high significance in efforts to improve agricultural productivity and efficiency. In addition to fostering technological innovations and precision farming solutions, in future this research aims to increase agricultural yields, particularly by enabling the cultivation of certain crops in locations different from their original ones.

：An effective technology for predicting the end-point phosphorous content of basic oxygen furnace (BOF) can provide theoretical instruction to improve the quality of steel via controlling the hardness and toughness. Given the slightly inadequate prediction accuracy in the existing prediction model, a novel hybrid method was suggested to more accurately predict the end-point phosphorus content by integrating an enhanced sparrow search algorithm (ESSA) and a multi-strategy with a deep extreme learning machine (DELM) as ESSA-DELM in this study. To begin with, the input weights and hidden biases of DELM were randomly selected, resulting in that DELM inevitably had a set of non-optimal or unnecessary weights and biases. Therefore, the ESSA was used to optimize the DELM in this work. For the ESSA, the Trigonometric substitution mechanism and Cauchy mutation were introduced to avoid trapping in local optima and improve the global exploration capacity in SSA. Finally, to evaluate the prediction efficiency of ESSSA-DELM, the proposed model was tested on process data of the converter from the Baogang steel plant. The efficacy of ESSA-DELM was more superior to that of other DELM-based hybrid prediction models and conventional models. The result demonstrated that the hit rate of end-point phosphorus content within ±0.003%, ±0.002%, and ±0.001% was 91.67%, 83.33%, and 63.55%, respectively. The proposed ESSA-DELM model could possess better prediction accuracy compared with other models, which could guide field operations.

Conventional flame retardant (FR) application processes for textiles involve aqueous processing which is resource intensive in terms of energy and water usage. Recent research using sol-gel and layer-by-layer chemistries, while claimed to be based on more environmentally-sustainable chemistry, still require aqueous media with the continuing problem of water management and drying processes being required. This paper outlines the initial forensic work to characterise commercially produced viscose/flax, cellulosic furnishing fabrics which have had conferred upon them durable flame retardant (FR) treatments using a novel, patented atmospheric plasma/UV excimer laser facility for processing textiles with the formal name - Multiplexed Laser Surface Enhancement (MLSE) system. This system (MTIX Ltd., UK), is claimed to offer the means of directly bonding of flame retardant precursor species to the component fibres introduced either before plasma/UV exposure or into the plasma/UV reaction zone itself, thereby eliminating a number of wet processing cycles. Nine commercial fabrics, pre-impregnated with a semi-durable, proprietary FR finish and subjected to the MLSE process have been analysed for their flame retardant properties before and after a 40 °C 30 min water soak. For one fabric, the pre-impregnated fabric was subjected to a normal heat cure treatment which conferred the same level of durability as the plasma/UV-treated analogue. TGA and LOI were used to further characterise their burning behaviour and the effect of the treatment on surface fibre morphologies were assessed. Scanning electron microscopy indicated that negligible changes had occurred to surface topography of the viscose fibres occurred during plasma/UV excimer processing.

Under Egyptian soil conditions, when phosphorus fertilizers were applied to the soil, it gets fixed and converts to unavailable form, leading to low solubility for the plant. This study were fulfilled on sweet potato (cv. Beauregard) under undesirable soil properties (CaCO3 10.8 vs 11.3%) using Bacillus megaterium DSM 2894 strain under different five mono calcium phosphate (CSP) levels [(69(CSP20); 138(CSP40); 207 (CSP60); 276 (CSP80) and 345 ((CSP100) kg ha-1 of calcium superphosphate (CSP)] to arise the potential efficiency of some nutrients uptake and decease the applied total amount of CSP in 2019 and 2020 seasons. The results mentioned that highest values were obtained by inoculated plants with DSM2894 strain under 20, 60 and 100% of CSP for all studied nutrients content in both seasons, except Mn content in the 2019. Also, inoculated plants with DSM2894 under previous treatments for all tuberous root nutrients content, except Fe and Zn contents in both seasons, in addition protein and anti-radical power and total yield. Statistically, leaf nutrients uptake and tuberous root content were highly significant affected by DSM and CSP combination. Appling of phosphorus fertilizer with DSM2894 mixture was gave the best values as compared with phosphorus fertilizer or DSM2894, individually.

Continuous research into the availability of phosphorus (P) in forest soil is critical for sustainable management of forest ecosystems. In this study, we used sequential chemical extraction and 31P-nuclear magnetic resonance spectroscopy (31P-NMR) to evaluate the form and distribution of inorganic P (Pi) and organic P (Po) in Casuarina forest soils of a subtropical coastal sand dune at Houlong in Taiwan. The soil samples were collected from humic (+2-0 cm) and mineral layers (mineral-I: 0-10, mineral-II: 10-20 cm) at two topographic locations (upland and lowland) by elevation. Sequential chemical extraction revealed that the NaOH-Po fraction, as moderately recalcitrant P, was the dominant form in humic and mineral-I layers in both upland and lowland soils, whereas the cHCl-Pi fraction was the dominant form in the mineral-II layer. Resistant P content, including NaOH-Pi, HCl-Pi, cHCl-Pi, and cHCl-Po fractions, was higher in the upland than lowland in the corresponding layers; however, labile P content, NaHCO3-Po, showed the opposite pattern. Content of resistant Pi (NaOH-Pi, HCl-Pi, and cHCl-Pi) increased significantly with depth, but that of labile Pi (resin-Pi and NaHCO3-Pi) and recalcitrant Po (NaHCO3-Po, NaOH-Po, and cHCl-Po) decreased significantly with depth at both locations. 31P-NMR spectroscopy revealed inorganic orthophosphate and monoesters-P as the major forms in this area. The proportions of Pi and Po evaluated by sequential chemical extraction and 31P-NMR spectroscopy were basically consistent. The results indicated that the soils were in weathered conditions. Furthermore, the P distribution and forms significantly differed between the upland and lowland by variation in elevation and eolian aggradation effects in this coastal sand dune landscape.

Phosphite (Phi) has gained attention in agriculture due to its biostimulant effect on crops. This molecule has been found to benefit plant performance by providing protection against pathogens, improving yield and fruit quality, and improving nutrient and water use efficiency. It is still unclear how Phi enhances plant growth and protects against multiple stresses. It has been hypothesized that Phi acts by directly affecting the pathogens and interacting with the plant cellular components and molecular machinery to elicit defense responses. This study delves into elucidating the mechanisms underlying Phi’s beneficial effects on plants, revealing a complex interplay with fundamental signaling pathways. A RNA-seq study of Arabidopsis seedlings under optimal and limiting phosphate conditions helped us unveil Phi’s role in promoting plant growth by activating the expression of genes involved in the biosynthesis and signaling pathways associated with abscisic acid (ABA), salicylic acid (SA), and jasmonic acid (JA). Expression of ABA-related genes, known for their involvement in stress response and development regulation, is triggered by Phi treatment, contributing to enhanced resilience and growth. Simultaneously, the activation of the SA pathway, associated with defense responses, suggests Phi’s potential in bolstering plant immunity. Moreover, Phi influences JA biosynthesis and signaling, which are crucial for defense against herbivores and pathogens, thereby strengthening plants’ defenses. Our findings reveal a multifaceted mechanism through which Phi benefits Arabidopsis development. Understanding its intricate interplay with key signaling pathways opens avenues for leveraging Phi as a strategic tool to enhance plant resilience, immunity, and growth in agricultural and ecological contexts.

Shipping is a vital component of global trade. However, shipping activities have negative environmental impacts, including emissions to air and water. The Baltic Sea is severely affected by eutrophication, mainly due to nutrient inputs, especially nitrogen and phosphorus. The aim of this research is to quantify the nutrient content of black and grey water discharged from cargo ships in the Baltic Sea in order to assess their contribution to the total nutrient load. Specifically, the research examines the nitrogen and phosphorus loadings from ships calling the port of HaminaKotka and addresses key questions regarding nutrient generation, discharge proportions, emission shares by ship type and their importance compared to other sources. Using a methodology based on ship data and nutrient production estimates, the study found that 2545 cargo ships generated a total of 781 kg of nitrogen and 134 kg of phosphorus in their effluents during their voyages to the port in 2021. However, only a small fraction (0.5%) of the cargo ships discharged their wastewater at port reception facilities. The study concludes that, although nutrient discharges from cargo ships are relatively small compared to other nutrient sources, efforts to promote port reception or onboard treatment are important for environmental sustainability. Further research is recommended to assess the effectiveness of onboard treatment systems, the impact of other contaminants in wastewater and the development of port reception facilities to facilitate proper wastewater management in the maritime trade.

Cumulative effects of landscape disturbance in forested source water regions can alter the storage of fine sediment and associated phosphorus in riverbeds, shift nutrient dynamics and degrade water quality. Here, we examine longitudinal changes in major element chemistry and particulate phosphorus (PP) fractions of river-bed sediment in an oligotrophic river during environmentally sensitive low flow conditions. Study sites along 50 km of the Crowsnest River were located below tributary inflows from sub-watersheds and represent a gradient of increasing cumulative sedi-ment pressures across a range of land disturbance types (harvesting, wildfire, and municipal wastewater discharges). Major elements (Si2O, Al2O3, Fe2O3, MnO, CaO, MgO, Na2O, K2O, Ti2O, V2O5, P2O5), loss on ignition (LOI), PP fractions (NH4CI-RP, BD-RP, NaOH-RP, HCI-RP and NaOH(85)-RP) and absolute particle size were evaluated for sediments collected in 2016 and 2017. While total PP concentrations were similar across all sites, bioavailable PP fractions (BD-RP, NaOH-RP) increased downstream with increased concentrations of Al2O3 and MnO and levels of landscape disturbance. This study highlights the longitudinal water quality impacts of increasing landscape disturbance on bioavailable PP in fine riverbed sediments and shows how the convergence of climate (wildfire) and anthropogenic (sewage effluent, harvesting, agriculture) drivers can produce legacy effects on nutrients.

The basis of modern teeth whitening systems is the use of a whitening gel, usually containing hydrogen peroxide or carbamide peroxide. The purpose of our study was to evaluate the effect of chemical and modified office teeth whitening systems on the mineral metabolism of oral fluid and to determine a safer method. The study covered 81 patients aged 22 to 35 years of both sexes with teeth color A2 and darker on the Vita Classic scale. Determination of the concentration of calcium and phosphates in the oral fluid was carried out on a spectrophotometer using ready-made Human kits. Chemical tooth whitening was performed using a gel based on 40% hydrogen peroxide. After the procedure, remineralization therapy with enamel-sealing liquid was performed for 14 days. The obtained results indicate that the most pronounced changes in the content of calcium (+74.4%, p &lt;0.001) and рhosphates (phosphorus) (-23.07%, p &lt;0.001) were observed when using a chemical bleaching system. After the teeth whitening procedure using a modified technique, less pronounced changes in the concentrations of calcium (+29.07, p &lt;0.001) and phosphorus (-14%, p &lt;0.001) were observed. The use of remineralizing agents led to a faster recovery of the initial levels of calcium and phosphates in the oral fluid. Both bleaching systems caused similar changes in the chemical composition of the oral fluid.

This study presents a novel lake ecosystem model that captures the intricate dynamics of nutrient cycling through nonlinear interactions. The model incorporates external phosphorus loading and internal recycling rates to explore a range of ecological outcomes, from stable equilibria to chaotic oscillations. We investigate the bifurcation phenomena within this model, revealing how changes in parameters can lead to significant shifts in ecosystem behavior. Our analysis demonstrates that the model can replicate behaviors similar to the Hénon map under specific parameter settings. Through numerical simulations, we examine the system's sensitivity to variations in nutrient parameters, uncovering the potential for unpredictable dynamics and chaos as the recycling rate increases. The emergence of chaotic behavior is further supported by entropy analysis, highlighting the model's complexity and its implications for real-world ecosystems. Notably, our findings resonate with the work of Tay et al., demonstrating that increased nutrient recycling can lead to bistability and abrupt shifts in ecosystem stability, emphasizing the critical importance of effective nutrient management to avert detrimental ecological consequences. This research contributes valuable insights into the dynamics of freshwater ecosystems, underscoring the intricate interplay between nutrient inflow, recycling, and bifurcation in maintaining ecological balance.

To understand the physiological basis of tolerance to combined stresses to low phosphorus (P) and drought in mungbean (Vigna radiata (L.) R. Wilczek), a core set of 100 accessions were evaluated in hydroponics at sufficient (250 μM) and low (3 μM) P, and exposed to drought (dehydration) stress. The principal component analysis and ranking of accessions based on relative values revealed that IC280489, EC397142, IC76415, IC333090, IC507340 and IC121316 performed superior while IC119005, IC73401, IC488526 and IC325853 performed poorly in all treatments. Selected accessions were evaluated in soil under control (sufficient P, irrigated), low P (without P, irrigated), drought (sufficient P, withholding irrigation) and combined stress (low P, withholding irrigation). Under combined stress, a significant reduction in gas exchange traits (photosynthesis, stomatal conductance, transpiration, instantaneous water use efficiency), P uptake in seed and shoot was observed under combined stress as compared to individual stresses. Among accessions, IC488526 was most sensitive while IC333090 and IC507340 exhibited tolerance to individual or combined stress. The water balance and low P adaptation traits like membrane stability index, relative water content, specific leaf weight, organic acid exudation, biomass, grain yield and P uptake can be used as physiological markers to evaluate for agronomic performance. Accessions with considerable resilience to low P and drought stress can be either used as ‘donors’ in Vigna breeding program or cultivated in areas with limited P and water availability or both.